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DEVELOPMENT OF A MOLECULAR MARKER FOR RUST RESISTANCE GENES Sr39 AND Lr35 IN WHEAT BREEDING LINES
Provedor de dados: Electronic Journal of Biotechnology
Polymorphic DNA bands were identified between a near iso-isogenic line of wheat carrying both stem (Sr39) and leaf (Lr35) rust resistance genes and the recurrent line Thatcher (Tc) which lacks these genes. Both resistance genes are located on a translocated chromosomal segment derived from Aegilops speltoides and thus are genetically linked. The primers used to generate polymorphic bands were 3'-anchored inter-simple sequence repeat primers which identified genomic microsatellites with a repeated motif of 3 nucleotides in length. The primers were used singly to amplify genomic segments which were flanked by inversely orientated, closely spaced, identical microsatellite sequences. One of the polymorphic bands, a 900 base pair band, was completely linked to...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000100004

Expression of the antibody 14D9 in Nicotiana tabacum hairy roots
Provedor de dados: Electronic Journal of Biotechnology
Autores: Martínez,Carolina; Petruccelli,Silvana; Giulietti,Ana María; Alvarez,María Alejandra.
Nicotiana tabacum hairy roots that express the antibody 14D9 were established. The 14D9 antibody yield obtained after 20 days of culture was 5.95 &amp;#956;g 14D9ml-1. The addition of the reticulum endoplasmic retention sequence KDEL demonstrated a positive effect over the intracellular 14D9 amounts with a yield increase up to 20.82 µg ml-1. DMSO increased the antibody amount in the biomass from 20.00 to 64.03 µg ml-1 while PVP (at 1.5 gl-1) and gelatine (at 5.0 gl-1) increased total 14D9 amounts in the culture medium to 25 µg and 14 µg respectively
Tipo: Journal article
Palavras-chave: Catalytic antibodies; In vitro cultures; Molecular farming; Recombinant antibodies; Tobacco.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200006

Recombinant expression and refolding of the c-type lysozyme from Spodoptera litura in E. coli
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kim,Jong-Wan; Yoe,Jeehyun; Lee,Gil Ho; Yoe,Sung Moon.
The chicken-type lysozyme of the insect Spodoptera litura (SLLyz) is a polypeptide of 121 amino acids containing four disulfide bridges and 17 rare codons and participates in innate defense as an anti-bacterial enzyme. The recombinant S. litura lysozyme (rSLLyz) expressed as a C-terminal fusion protein with glutathione S-transferase (GST) in Rosetta(DE3) Singles. The protein was produced as an inclusion body which was solubilized in 8 M urea, renatured by on-column refolding, and purified by reversed-phase chromatography to 95% purity. The purified rSLLyz demonstrated antibacterial activity against B. megaterium confirmed by inhibition zone assay. The overexpression and refolding strategy described in this study will provide a reliable technique for...
Tipo: Journal article
Palavras-chave: Antibacterial activity; Inclusion body; Lysozyme; On-column refolding; Recombinant expression; Spodoptera litura.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300006

Plant genomics and agriculture: From model organisms to crops, the role of data mining for gene discovery
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mahalakshmi,Viswanathan; Ortiz,Rodomiro.
Sequencing and analysing of the Arabidopsis thaliana genome, the first plant kingdom genome to be unraveled, will always remain a scientific landmark. International initiatives to sequence rice, the most important cereal in Asia, are underway. However as functional information piles up in Arabidopsis and rice, researchers working in other crops will benefit from this new knowledge and apply it to their studied plants or crop species. The increasing role of public databases of model organisms and bio-informatics in data mining, presents a new opportunity as well as a challenge to researchers to develop more focused molecular tools for gene discovery and deployment. The work presented in here describes how such an approach has benefited sorghum, a rainfed...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300012

Teaching the principles of biotechnology transfer: A service-learning approach
Provedor de dados: Electronic Journal of Biotechnology
Autores: Montgomery,Beronda L.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000100004

Analysis of a suppressive subtractive hybridization library of Alternaria alternata resistant to 2-propenyl isothiocyanate
Provedor de dados: Electronic Journal of Biotechnology
Autores: García-Coronado,Heriberto; Troncoso-Rojas,Rosalba; Tiznado-Hernández,Martín Ernesto; de la Cruz Otero,María del Carmen; Díaz-Camacho,Sylvia Páz; Báez-Flores,María Elena.
Background Isothiocyanates (ITCs) are natural products obtained from plants of the Brassicas family. They represent an environmentally friendly alternative for the control of phytopathogenic fungi. However, as it has been observed with synthetic fungicides, the possibility of inducing ITC-resistant strains is a major concern. It is, therefore, essential to understanding the molecular mechanisms of fungal resistance to ITCs. We analyzed a subtractive library containing 180 clones of an Alternaria alternata strain resistant to 2-propenyl ITC (2-pITC). After their sequencing, 141 expressed sequence tags (ESTs) were identified using the BlastX algorithm. The sequence assembly was carried out using CAP3 software; the functional annotation and metabolic pathways...
Tipo: Journal article
Palavras-chave: Blast2GO analysis; Fungal drug tolerance; Isothiocyanates; Natural fungicides.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400011

Efficiency of improved RAPD and ISSR markers in assessing genetic diversity and relationships in Angelica sinensis (Oliv.) Diels varieties of China
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mei,Zhiqiang; Zhang,Chun; Khan,Asaduzzaman; Zhu,Ye; Tania,Mousumi; Luo,Peiyi; Fu,Junjiang.
Background Angelica sinensis is a well-known traditional Chinese medicinal plant. We aimed to assess the genetic diversity and relationships in A. sinensis cultivars collected from different locations of China and also some other Angelica species. Results We employed an improved random amplified polymorphic DNA (RAPD) technique for the amplification of DNA materials from ten Angelica cultivars, and the results were verified by inter-simple sequence repeat (ISSR) analysis. Twenty six RAPD primers were used for RAPD, and the amplified bands were found highly polymorphic (96%). Each primer amplified 8-14 bands with an average of 10.25. The cluster dendrogram showed that the similarity coefficients ranged from 0.41 to 0.92. The similarity coefficients were...
Tipo: Journal article
Palavras-chave: Angelica sinensis; Genetic authentication; Inter-simple sequence repeat; Random amplified polymorphic DNA; Substitutes.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200006

Enzymatic synthesis of short chain citronellyl esters by a new lipase from Rhizopus sp
Provedor de dados: Electronic Journal of Biotechnology
Autores: Alves Macedo,Gabriela; Soberón Lozano,Maria Mercedez; Pastore,Gláucia Maria.
Short chain citronellyl esters were synthesized by a new microbial lipase from Rhizopus sp strain isolated and lipase produced at UNICAMP, Brazil. Direct esterification and transesterification reactions have been performed to produce citronellyl acetate and butyrate in a free-solvent system and with n-hexane in reaction medium. Reaction mixture for direct esterification and transesterification was carried out at 45ºC in equimolar concentration of substrates: acid or ester and alcohol. Only citronellyl butyrate was synthesized by direct esterification with yields from 95 to 100% after 24 hrs. of reaction time, with or without n-hexane. Citronellyl acetate was synthesized by transesterification with ethyl acetate and cytronellol, with yield of 58% after 48...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000100009

Immobilized lysozyme protein on fibrous medium: Preliminary results for microfiltration applications
Provedor de dados: Electronic Journal of Biotechnology
Autores: Assis,Odilio B. G.; Claro,Luis C.
The protein lysozyme was deposited onto a permeable support comprising chemically functionalized glass fiber. The main objective of this study was to set a stable organic net with no effect on the medium bed permeability and a preliminary test the activity of this enzyme under immobilized conditions. The film formation is followed by atomic force microscopy (AFM) surface imaging. The effect on the bacteria Escherichia coli was tested using a simple microfiltration column. The filtration results pointed around 75% removal of bacteria in the effluent when compared to the influent concentration. The removal mechanism is assumed as being essentially due biointeraction. The surface polarity characteristics of the formed film were also considered as playing an...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000200010

Amplification of tlh gene in other Vibrionaceae specie by specie-specific multiplex PCR of Vibrio parahaemolyticus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yáñez,Romina; Bastías,Roberto; Higuera,Gastón; Salgado,Oscar; Katharios,Pantelis; Romero,Jaime; Espejo,Romilio; García,Katherine.
Background The surveillance of Vibrio parahaemolyticus in the Chilean coast has been mainly performed by multiplex PCR amplification of three different hemolysin genes, which are specie-specific virulence factors. These genes are also employed in the determination of V. parahaemolyticus pathogenic load in seafood and for characterization of pathogenic strains associated to diarrhea cases in human. During environmental surveillance that we performed every summer, we occasionally observed a thermolabile hemolysin (tlh) PCR product of a slightly smaller size than expected, which was coincident with low loads of V. parahaemolyticus in the environment. In order to understand this observation, we probed the specificity of tlh primers for the detection of V....
Tipo: Journal article
Palavras-chave: Hemolysin; Multiplex PCR; Pathogen surveillance; Virulence factor; Vibrio parahaemolyticus.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600012

NBBnet - The National Biotechnology and Bioinformatics Network: A Malaysian initiative towards a national infrastructure for bioinformatics
Provedor de dados: Electronic Journal of Biotechnology
Autores: Raih,Mohd Firdaus; Harmin,Sharr Azni; Ahmad,Hafiza Aida; Mat Isa,Mohd Noor; Mahadi,Nor Muhammad; Ibrahim,Abdul Latif; Mohamed,Rahmah.
Bioinformatics is a necessary technology and tool, which current molecular biologists cannot do without in light of the genome data explosion and advent of fields such as genomics and proteomics. Yet, even with this in mind, there is still a limited pool of human resource to support and develop bioinformatics particularly in poorer developing nations. The highly multidisciplinary nature of this field can be an obstacle in converting just any molecular biologist into a proficient and capable bioinformaticist. Coupled with the high costs of software, hardware, technical maintenance and systems support; many developing and poor countries may not be able to fully realize their biotech potential either academically or economically due to the inability to fully...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000100003

A simple negative selection method to identify adenovirus recombinants using colony PCR
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhao,Yongliang; Dong,Zongming; Li,Tengfei; Huang,Gang.
Background: The AdEasy system is a fast-track system for generating recombinant adenoviruses using the efficient homologous recombination machinery between shuttle and adenovirus backbone plasmids in Escherichia coli BJ5183 cells. The key step is homologous recombination in BJ5183 cells, which is driven by RecA activity. However, culture time is stringently limited to reduce the damage to recombinant plasmids by RecA activity. Therefore, rapid identification of recombinant adenoviruses within the limited time-period is critical. Results: We developed a simple negative selection method to identify recombinant adenoviruses using colony PCR, which improves the efficiency of adenovirus recombination screening and packaging. Conclusions: The negative selection...
Tipo: Journal article
Palavras-chave: Adenovirus; AdEasy; Colony PCR; Homologous recombination; RecA.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100008

Lipase-catalyzed enantioselective esterification of flurbiprofen with n-butanol
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bhandarkar,Satej V.; Neau,Steven H.
The influences of water activity and solvent hydrophobicity on the kinetics of the lipase-catalyzed enantioselective esterification of flurbiprofen with n-butanol were investigated. The solvent effect was not similar for lipases from Candida rugosa (Crl), Mucor javanicus (Mjl), and porcine pancreas (Ppl). The lipase-catalyzed reaction rates in different solvents across a wide range of water activities revealed that the Ppl-catalyzed reaction exhibited no enantioselectivity and no substantial water activity or solvent dependence. The Mjl-catalyzed reaction proceeded faster, preferring the R-enantiomer reaction over that of its antipode, but had little solvent or water activity dependence. The Crl-catalyzed reactions in n-heptane and n-nonane had similar...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000300003

Response surface methodology used for statistical optimization of jiean-peptide production by Bacillus subtilis cells adsorbed on wood chips
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Xiaoyong; Zhou,Jinyan; Fu,Wen; Li,Zhidong; Zhong,Juan; Yang,Jie; Xiao,Liang; Tan,Hong.
Response surface methodology (RSM) was used for statistical optimization of jiean-peptide (JAA) production by Bacillus subtilis ZK8 cells adsorbed on wood chips to form a novel fermentation system. The Plackett-Burman design was used in the first step to evaluate the effects of eight factors, including six fermentation medium components and two cell adsorption conditions. Among the variables screened, soybean meal hydrolysate (SMH) and MgSO4·7H2O in the fermentation medium had significanteffects on JAA production. In the second step, the concentrations of SMH and MgSO4·7H2O were further optimized using central composite designs and response surface analysis. The optimized concentration of SMH and MgSO4·7H2O was 24% (v/v) and 0.38% (w/v), respectively,...
Tipo: Journal article
Palavras-chave: Bacillus subtilis ZK8; Cell adsorption; Jiean- peptide; Response surface methodology; Wood chips.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400006

Improved sanitary landfill design using recirculation of anaerobically treated leachates: generation of advanced design criteria
Provedor de dados: Electronic Journal of Biotechnology
Autores: Schiappacasse,MarÃ­a Cristina; Palma,Juan; Poirrier,Paola; Ruiz-Filippi,Gonzalo; Chamy,Rolando.
In Latin Americ a, the most accepted disposal systems for Municipal Solid Waste (MSW) are landfills, which nowadays have low rates of stabilization. The objective of this study was to develop design criteria for sanitary landfills which lead to a reduction in the stabilization times of MSW, based on experiment results obtain from a pre-pilot scale operation of two sanitary landfills (0.5 Ton), one with recirculation of leachates treated in an anaerobic digester and the other with recirculation of untreated leachates. This was complemented by another pilot scale sanitary landfill (1440 Ton) with recirculation of leaches treated in an anaerobic filter, and additionally by a computer simulation of leachate generation through the water balance of a theoretical...
Tipo: Journal article
Palavras-chave: Hydrological balance; Landfill; Leachate recycle; Municipal solid waste; Stabilization.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300009

Overexpression of a cysteine proteinase inhibitor gene from Jatropha curcas confers enhanced tolerance to salinity stress
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Rui; Wang,Wanjun; Wang,Wenguo; Li,Fosheng; Wang,Qingwei; Xu,Ying; Wang,Shenghua.
Background Cysteine proteinase inhibitor (cystatin, CPI) is one of the most important molecules involved in plant development and defense, especially in the regulation of stress responses. However, it is still unclear whether the Jatropha curcas CPI (JcCPI) gene functions in salinity response and tolerance. In this study, the sequence of the JcCPI gene, its expression pattern, and the effects of overexpression in Escherichia coli and Nicotiana benthamiana were examined. The purpose of this study was to evaluate the regulatory role of JcCPI in salinity stress tolerance. Results The CPI gene, designated JcCPI, was cloned from J. curcas; its sequence shared conserved domains with other plant cystatins. Based on a transcription pattern analysis, JcCPI was...
Tipo: Journal article
Palavras-chave: Cysteine proteinase inhibitor; Jatropha curcas; Salinity stress.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500008

A preferable approach to clone hLIF cDNA from the genomic DNA
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cui,Yihong; Zhu,Guangqin; Chen,Qiuju; Wang,Yunfei; Yang,Mingming; Song,Yuxuan; Wang,Jiangang; Cao,Binyun.
Complementary DNA (cDNA) is valuable for investigating protein structure and function in the research of life science, but it is difficult to obtain by traditional reverse transcription. In this study, we employed a novel strategy to clone the human leukemia inhibitory factor (hLIF) gene cDNA from genomic DNA directly isolated from the mucous membrane of mouth. The hLIF sequence can be acquired within a few hours by means of amplification of each exon and splicing using overlap-PCR. Thus, the new approach developed in this study is simple, time- and cost-effective, and it is not limited to particular gene expression levels of each tissue.
Tipo: Journal article
Palavras-chave: CDNA cloning; HLIF; Oral mucous membrane; Overlap PCR.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300012

Callus culture development of two varieties of Tagetes erecta and carotenoid production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Benítez-García,Israel; Vanegas-Espinoza,Pablo Emilio; Meléndez-Martínez,Antonio J; Heredia,Francisco J; Paredes-López,Octavio; Del Villar-Martínez,Alma Angélica.
Background The properties of natural pigments, such as antioxidants, functional, medical, and nutraceutical, have demonstrated the advantages of these natural compounds over synthetic ones. Some products are accepted only when they are pigmented with natural, food-quality colorants: for example poultry products (manly marigold flower extracts). Carotenoids such as &amp;#946;-carotene, &amp;#946;-criptoxanthin and lutein are very attractive as natural food colorants due to their antioxidant and pro-vitamin activities which provide additional value to the target products. Marigold (Tagetes erecta) is an Asteraceous ornamental plant native to Mexico, and it is also important as a carotenoid source for industrial and medicinal purposes but nowadays its...
Tipo: Journal article
Palavras-chave: 2 4-D; BA Cell development Lutein Marigold.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000300001

Valorization of raw glycerol for citric acid production by Yarrowia lipolytica yeast
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rywinska,Anita; Rymowicz,Waldemar; Marcinkiewicz,Marta.
In the present report, citric acid production from raw glycerol in two fed-batch systems by acetate negative-mutants of Yarrowia lipolytica: Wratislavia 1.31 and Wratislavia AWG7 was compared. In the system, in which the total glycerol concentration was 200 g&amp;#8729;L-1, the substrate was added by pulsed additions, and in the other, in which the total glycerol concentration was 300 g&amp;#8729;L-1, the substrate was added at a constant feeding rate of 1.4 g&amp;#8729;h-1. Despite high citric acid concentrations (155.2 and 157.5 g&amp;#8729;L-1 with Y. lipolytica Wratislavia 1.31 and Y. lipolytica Wratislavia AWG7, respectively) obtained from 300 g&amp;#8729;L-1 of glycerol, the yield of citric acid was similar, i.e. about 0.6 g&amp;#8729;g-1. The...
Tipo: Journal article
Palavras-chave: Citric acid; Fed-batch culture; Yarrowia lipolytica; Raw glycerol.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400009

Influence of metal ions and organic carbons on denitrification activity of the halotolerant bacterium, Paracoccus pantotrophus P16 a strain from shrimp pond
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pintathong,Punyawatt; Richardson,David J; Spiro,Stephen; Choorit,Wanna.
The effect of metal ions, ferric ion (Fe3+) and molybdenum ion (Mo6+) on the denitrification process of Paracoccus pantotrophus P16 grown under saline conditions was investigated. Results revealed that the dosages of added Fe3+ and Mo6+ significantly accelerated nitrate utilization and nitrite accumulation. Enzymatic studies revealed that the membrane-bound nitrate reductase and the periplasmic nitrite reductase had activities of 998 ± 28 and 373 ± 18 nmol (mg protein)-1 min-1, respectively after growing Paracoccus pantotrophus P16 in medium supplemented with 1.5 µM Fe3+. If provided with 1.5 µM Fe3+and 2.4 µM Mo6+, the membrane-bound nitrate reductase activity increased to 6,223 ± 502 nmol (mg protein)-1 min-1 and the periplasmic nitrite reductase was 344...
Tipo: Journal article
Palavras-chave: Metal ions; Nitrate reductase; Nitrite accumulation; Nitrite reductase; Paracoccus pantotrophus.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200004

Molecular description and similarity relationships among native germplasm potatoes (Solanum tuberosum ssp. tuberosum L.) using morphological data and AFLP markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Solano Solis,Jaime; Morales Ulloa,Daniza; Anabalón Rodríguez,Leonardo.
Chile is considered to be a sub-center of origin for the cultivated potato, with native and introduced genetic material coexisting in the country. Thus, the different varieties present in Chiloe Island are characterized by a rich diversity of forms, sizes, colours and phenological characteristics. In the present work, the level of polymorphism and the genetic relationship were studied by means of molecular markers using the amplified fragment length polymorphism (AFLP) technique and twenty-seven morphological characters. Twenty varieties of potatoes from the Chiloe Island were analyzed. The commercial variety Desirée and one specie from the Etuberosa series, Solanum fernandezianum, collected in the Juan Fernandez Island were included as controls. A...
Tipo: Journal article
Palavras-chave: Cluster analysis; Molecular markers; Solanum tuberosum ssp. tuberosum.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300011

Immature embryo: A useful tool for oil palm (Elaeis guineensis Jacq.) genetic transformation studies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Abdullah,Ruslan; Zainal,Alizah; Yew Heng,Wee; Chui Li,Leaw; Chee Beng,Yeap; Mei Phing,Lee; Abdullah Sirajuddin,Salwa; Soo Ping,Winnie Yap; Lourdes Joseph,Juanita; Azma Jusoh,Siti.
Oil palm (Elaeis guineensis Jacq.) is the highest yielding oil-bearing crop. However, being a perennial crop, genetic improvement of oil palm is extremely slow. Indeed, compared to other annual oil crops such as soybean and rapeseed, genetic manipulations remained less important. Therefore, to remain competitive, oil palm growers and breeders need new and novel approaches. In this report, the potential of immature embryos (IE) as a useful tool for oil palm genetic transformation studies was evaluated. It was evident that IEs were amenable to both direct and Agrobacterium-mediated gene transfer. Due to the abundant supply of IE, optimization of biolistic and Agrobacterium-mediated gene transfer into IEs were easily carried out. Transient transformation...
Tipo: Journal article
Palavras-chave: Genetic transformation studies; Immature embryos; In vitro culture; Oil palm; Plant regeneration.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100006

The upstream sequence of the phycocyanin b subunit gene from Arthrospira platensis regulates expression of gfp gene in response to light intensity
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yongzhong,Lu; Zhang,Xuecheng.
In cyanobacteria, few details are known of the mechanisms through which the expression of the light-harvesting pigment c-phycocyanin is regulated. In the present study, a 419 bp upstream sequence of the phycocyanin b subunit (cpcB) gene from Arthrospira platensis FACHB341 was fused with green fluorescent protein (gfp) gene, and a heterologous reporting system was built up to investigate the influence of light intensity on the expression of gfp gene, and the regulation function of different region of the upstream sequence of cpcB gene. Results showed that the upstream sequence of cpcB gene could drive the expression of gfp gene in Synechococcus sp. strain PCC7942, and the expression was influenced by light intensity, the lower the light intensity, the...
Tipo: Journal article
Palavras-chave: CpcB gene; Deletion analysis; Light intensity; Synechococcus; Transformation.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100010

Cultivation of Scenedesmus dimorphus for C/N/P removal and lipid production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Xu,Xinmiao; Shen,Ying; Chen,Jiacheng.
Background CO2 emission, water pollution and petroleum shortage are the issues coming with the development of industry. A cost effective system was constructed to fix the CO2 in flue gas (15% CO2), remove nitrogen and phosphorus from manure wastewater and produce biofuels at the same time. The significant cultivation conditions were selected by Plackett-Burman design, and then optimized with central composite design. Results Optimum culture condition was predicted at light intensity of 238 µmol·m- 2·s- 1, TN of 152 mg·L- 1, inoculum density of 0.3 g·L- 1, under which the measured CO2 fixation rate, total nitrogen and phosphorus removing rate, and lipid content were 638.13 mg·L- 1·d- 1, 88.16%, 73.98% and 11.9%, respectively. The lipid content was then...
Tipo: Journal article
Palavras-chave: CO2 fixation rate; Flue gas; Lipid content; Scenedesmus dimorphus; Wastewater.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100009

Biosorption of chromium (VI) from aqueous solutions by the husk of Bengal gram (Cicer arientinum)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ahalya,N; Kanamadi,R.D; Ramachandra,T.V.
The potential to remove Cr (VI) from aqueous solutions through biosorption using the husk of Bengal gram (Cicer arientinum), was investigated in batch experiments. The results showed removal of 99.9% of chromium in the 10 mgl-1 chromium solution, the biomass required at saturation was 1 g mg-1. Kinetic experiments revealed that the dilute chromium solutions reached equilibrium within 180 min. The biosorptive capacity of the (bgh) was dependent on the pH of the chromium solution, with pH 2 being optimal. The adsorption data fit well with the Langmuir and Freundlich isotherm models. The adsorption capacity calculated from the Langmuir isotherm was 91.64 mg Cr (VI)/g at pH 2. The adsorption capacity increased with increase in agitation speed and an optimum...
Tipo: Journal article
Palavras-chave: Agro-wastes; Bengal gram husk (bgh); Cicer arientinum; Chromium biosorption; Isotherms; Fourier transform infrared spectroscopy (FTIR).
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300005

An improved system for competent cell preparation and high efficiency plasmid transformation using different Escherichia coli strains
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tu,Zhiming; He,Guangyuan; Li,Kexiu X.; Chen,Mingjie J.; Chang,Junli; Chen,Ling; Yao,Qing; Liu,Dongping P.; Ye,Huan; Shi,Jiantao; Wu,Xuqian .
This paper describes an efficient bacterial transformation system that was established for the preparation of competent cells, plasmid preparation, and for the storage in bacterial stocks in our laboratory. Using this method, a number of different plasmids have been amplified for further experiments. Competent cells for bacterial transformation were prepared by the calcium chloride method with an optimum concentration of 75 mM. Three different strains of Escherichia coli that were tested are DH5&amp;#945;, TG1 and XL1 blue, and the most efficient strain being XL1 blue. The optimal optical density (OD600) range for competent cell preparation varied for each of the strains investigated, and for XL1 blue it was 0.15-0.45; for TG1 it was 0.2-0.5; and for...
Tipo: Journal article
Palavras-chave: Competent cells; E. coli; Plasmid; Storage; Transformation.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100014

A standardized protocol for genomic DNA isolation from Terminalia arjuna for genetic diversity analysis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sarwat,Maryam; Singh Negi,Madan; Lakshmikumaran,Malathi; Kumar Tyagi,Akhilesh; Das,Sandip; Shankar Srivastava,Prem.
For studying genetic diversity in natural populations of Terminalia, a medicinal plant, our attempts to isolate high quality DNA using several previously reported protocols and even modifications were unsuccessful. We therefore combined CTAB based isolation, and column based purification step, to isolate DNA from Terminalia arjuna. The DNA isolated using this standardized protocol was high in quality and suitable for restriction digestion and generation of random amplification of polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP).
Tipo: Journal article
Palavras-chave: DNA extraction; Medicinal plants; Molecular markers; Terminalia species.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100011

Lettuce (Lactuca sativa L.) seed quality evaluation using seed physical attributes, saturated salt accelerated aging and the seed vigour imaging system
Provedor de dados: Electronic Journal of Biotechnology
Autores: Peñaloza,Patricia; Ramirez-Rosales,Gerardo; McDonald,Miller B; Bennett,Mark A.
High seed quality is essential for optimum stand establishment in lettuce. As a result, it is necessary to have seed vigour tests that permit rapid, objective and accurate evaluation of seed quality. This study evaluated physical and physiological seed quality components of four seed lots of six lettuce varieties obtained from a commercial company. Seeds were evaluated for seedling emergence under greenhouse conditions, standard germination, seed physical aspects, the Saturated Salt Accelerated Aging (SSAA) test and the Seed Vigour Imaging System (SVIS). Results indicated that large-seeded lettuce varieties had higher percentage germination, higher SSAA values, higher SVIS index and more rapid and uniform greenhouse emergence. Black-seeded lettuce...
Tipo: Journal article
Palavras-chave: Vegetables; Deterioration; Seedling; Performance.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300010

Natural antifouling compound production by microbes associated with marine macroorganisms: A review
Provedor de dados: Electronic Journal of Biotechnology
Autores: Satheesh,Sathianeson; Ba-akdah,Mohammad Abdulaziz; Al-Sofyani,Abdulmohsin A.
In the marine environment, all hard surfaces including marine macroorganims are colonized by microorganisms mainly from the surrounding environment. The microorganisms associated with marine macroorganisms offer tremendous potential for exploitation of bioactive metabolites. Biofouling is a continuous problem in marine sectors which needs huge economy for control and cleaning processes. Biotechnological way for searching natural product antifouling compounds gained momentum in recent years because of the environmental pollution associated with the use of toxic chemicals to control biofouling. While, natural product based antifoulants from marine organisms particularly sponges and corals attained significance due to their activities in field assays,...
Tipo: Journal article
Palavras-chave: Antifouling; Biofouling; Bioactive compounds; Marine biotechnology; Marine microbes.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300012

Toxicity caused by para-substituted phenols on Tetrahymena pyriformis: The structure-activity relationships
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jäntschi,Lorentz; Popescu,Violeta; Bolboaca,Sorana D.
The toxicity of thirty para-substituted phenols on Tetrahymena pyriformis was modelled using an original methodology that uses the complex structural information of the compounds. Two models were built. The methodology allows atomic properties to be assigned to toxicity based on the selection of pairs of descriptors from the entire family, which is called Molecular Descriptors Family (MDF). One model has two independent structural descriptors and the other has four. The model with four descriptors proved to have high estimated and predictive abilities (over 97% of toxicity could be explained by structural information). The partial charge distribution by bonds (molecular topology) and space (molecular geometry) interaction proved to be related with the...
Tipo: Journal article
Palavras-chave: Para-substituted phenol derivatives; Structure-activity relationships; Tetrahymena pyriformis; Toxicity.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300012

Stimulation of trans-resveratrol biosynthesis in Vitis vinifera cv. Kyoho cell suspension cultures by 2, 3-dihydroxypropyl jasmonate elicitation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Shen,Xu; Du,Qingshan; Xu,Yufang; Lu,Yanhua.
Background: Plant cell suspension culture of Vitis vinifera is a promising technology for investigating different factors that are able to induce and/or modify stilbenes biosynthesis. Jasmonates have been reported to play an important role in a signal transduction pathway that regulates defence responses as well as the production of secondary metabolites. In this study, 2, 3-dihydroxypropyl jasmonate (DHPJA) was used to investigate its effect on stimulating trans-resveratrol (t-R) accumulation and the plant defence responses in Vitis vinifera cv. Kyoho cell suspension cultures for the first time. Results: It demonstrated that DHPJA had superior effects on stilbenoids accumulation over methyl jasmonate (MeJA). The optimal condition was 150 &amp;#956;M DHPJA...
Tipo: Journal article
Palavras-chave: 2; 3-dihydroxypropyl jasmonate H2O2 trans-resveratrol Vitis vinifera cell suspension cultures.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500003

Aerobic biodegradation of nonylphenol ethoxylates in shaking-flask test
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Ping; Nong,Xu-Hua; Ge,Jie-Hong.
Nonylphenol ethoxylates (NPEOs), which are widely used for industrial and domestic purposes, exert adverse effects on wildlife after being used and discharged into the environment. However, their ultimate biodegradability and biodegradation pathway remains unclear. In this study, the aerobic degradability of nonylphenol ethoxylates (NPEOs) by the acclimated microorganisms in active sludge was examined using shaking-flask tests. The degradation of benzene rings in NPEOs was determined using UV spectroscopy and high performance liquid chromatography (HPLC). Results showed that more than 80% of benzene rings were removed after 8-10 days of degradation, and the majority of NPEOs were also removed after 9 days of degradation, indicating NPEOs and the benzene...
Tipo: Journal article
Palavras-chave: Aerobic biodegradation; Degradation pathway; ESI-MS; HPLC; Nonylphenol ethoxylates.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400001

Development of pollen mediated activation tagging system for Phalaenopsis and Doritaenopsis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tsay,Hsin-Sheng; Ho,Hui-Min; Gupta,Sushim K; Wang,Chang-Sheng; Chen,Pei-Tsu; Chen,Emily Chin-Fun.
In the present study, a novel plant transformation system for Doritaenopsis and Phalaenopsis has been developed. The pollen-mediated activation tagging system was established by artificial pollination. The pollens, co-cultured with Agrobacterium tumefaciens strain EHA105 harbouring an activation tagging vector (pTAG-8), were used for pollination. In order to optimize the transformation efficiency, several factors (concentration of A. tumefaciens, concentration of acetosyringone during co-cultivation and the duration of co-cultivation) known to influence Agrobacterium-mediated DNA transfer were examined. A concentration of 0.5-1 x 10(8) CFU/ml for A. tumefaciens, 0.1 mM acetosyringone, and 6 hrs of co-culture period were found to be the optimal condition...
Tipo: Journal article
Palavras-chave: Activation tagging; Agrobacterium tumefaciens; Doritaenopsis cultivars; Phalaenopsis amabilis; Transformation.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000400009

Resistance of diethylenetriaminepentaacetic acid to anaerobic biodegradation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Alarcón,Evelyn; Decap,Jacqueline; Vidal,Gladys.
Kraft mills are responsible for the massive discharge of highly polluted effluents, and new bleaching processes (i.e. Total Chlorine Free (TCF)) is presented as a feasible option to reduce this environmental impact. However, increased TCF pulp production is accompanied by an increase in chelate use. The most commonly used chelates, ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DPTA), are considered to be relatively persistent substances in water treatment plants, and consequently environmentally critical compounds. The purpose of this work is to investigate DPTA behaviour in an anaerobic system. An Anaerobic Filter (AF) was operated with three different DPTA load rates (LR DPTA = 0.07 - 0.28 gDPTA/L&amp;times;d), and the...
Tipo: Journal article
Palavras-chave: Anaerobic biodegradation; DTPA; Kraft mill effluent.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300011

Suppression subtractive hybridization PCR isolation of cDNAs from a Caribbean soft coral
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lopez,Jose V; Ledger,Angela; Santiago-Vázquez,Lory Z; Pop,Mihai; Sommer,Dan D; Ranzer,Llanie K; Feldman,Robert A; Russell,G. Kerr.
Transcriptomic studies of marine organisms are still in their infancy. A partial, subtracted expressed sequence tag (EST) library of the Caribbean octocoral Erythropodium caribaeorum and the sea fan Gorgonia ventalina has been analyzed in order to find novel genes or differences in gene expression related to potential secondary metabolite production or symbioses. This approach entails enrichment for potential non-&amp;#8220;housekeeping&amp;#8221; genes using the suppression subtractive hybridization (SSH) polymerase chain reaction (PCR) method. More than 500 expressed sequence tags (ESTs) were generated after cloning SSH products, which yielded at least 53 orthologous groups of proteins (COGs) and Pfam clusters, including transcription factors (Drosophila...
Tipo: Journal article
Palavras-chave: CDNA; Erythropodium caribaeorum; EST; Gorgonia ventalina; Gorgonian; Sea fan.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100008

Biosorption of uranium from aqueous solutions by nonliving biomass of marinealgae Cystoseira indica
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hassan Khani,Mohammad; Reza Keshtkar,Ali; Meysami,Behrouz; Firouz Zarea,Mohammad; Jalali,Reza.
Biosorption of heavy metals can be an effective process for the removal and recovery of heavy metal ions from aqueous solutions. In this paper uranium biosorption by protonated, Ca-pretreated and non-pretreated Cystoseira indica algae biomass was investigated in a batch system. The results of the kinetic studies showed that the sorption of uranium on protonated and non-pretreated biomass followed pseudo-second order kinetics. The effect of pH on the equilibrium uranium sorption capacity of Cystoseira indica exhibited that highest uptake occurred at pH 4 at a solution with 350 mg/l uranium concentration. At various initial uranium concentrations from 50 to 1000 mg/l, batch sorption equilibrium at 30&amp;ordm;C was reached within 3 hrs and the sorption...
Tipo: Journal article
Palavras-chave: Biosorption; Cystoseira indica; Equilibrium; Kinetic; Marine algae; Uranium.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200003

Treatment of low strength sewage with high suspended organic matter content in an anaerobic sequencing batch reactor and modeling application
Provedor de dados: Electronic Journal of Biotechnology
Autores: Donoso-Bravo,Andrés; Carballa,Marta; Ruiz- Filippi,Gonzalo; Chamy,Rolando.
In this work, an anaerobic sequencing batch reactor (ASBR) was operated for 8 months to treat low strength sewage with high suspended organic matter content. Three phases of operation with increasing organic loading rates (OLR) were performed: 0.4 kg COD/m³ x d (phase I), 0 .8 kg COD/m³ x d (phase II) and 1.2 kg COD/m³ x d (phase III). Adequate stability parameters (pH, total alkalinity) were obtained through all three experimental phases. During phases I and II, the removal efficiencies of organic matter (expressed as total chemical oxygen demand (COD) and total suspended solids ranged between 50-60%. However, these values decreased to 15-25% in phase III. In addition, a non-complex model, including hydrolysis, acidogenesis and methanogenesis, was applied...
Tipo: Journal article
Palavras-chave: Acidogenesis; Anaerobic treatment; Hydrolysis; Low strength wastewater; Modeling.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300013

Functional complementation in Saccharomyces cerevisiae under control of the natural yeast promoter
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lavigne,Rob; Volckaert,Guido.
A novel approach for functional complementation of foreign genes in Saccharomyces cerevisiae is presented. This approach is based on the use of the widely available cognate gene plasmids (e.g. pRS416) of the European Functional Analysis Network (EUROFAN). The functional complementation of the human homolog of YOR159c (SME1 gene) shown here is the first demonstration of complementation using the original yeast promoter, theoretically offering a more natural regulation of protein expression
Tipo: Journal article
Palavras-chave: Cognate gene plasmid; Functional complementation homolog Saccharomyces cerevisiae yeast.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200014

Biotechnology Education in Schools
Provedor de dados: Electronic Journal of Biotechnology
Autores: Harms,Ute.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300003

Evaluation of cassava plants generated by somatic embryogenesis at different stages of development using molecular markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Osorio,Mayra; Gámez,Elizabeth; Molina,Sandy; Infante,Diógenes.
Background: Cassava (Manihot esculenta Crantz) is a crop that is high in carbohydrates in the roots and in protein in the leaves, important for both human consumption and animal feed, and also has a significant industrial use for its starches. In this study we evaluated the genetic variability with molecular markers in different stages in micropropagated plants from somatic embryos of Venezuelan native clone 56. Results: Three markers were used: ISTR, AFLP and SSR, finding that ISTR showed the highest polymorphism among individuals tested. With AFLP a high similarity between the evaluated individuals was observed and with SSR total monomorphism was seen. Using cluster analysis it was found that individuals from an embryo labeled as fasciated at the...
Tipo: Journal article
Palavras-chave: AFLP; Genetic stability; ISTR; SSR; UPGMA.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000400003

Global analysis of gene function in mammals: Integration of physical, mutational and expression strategies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Schimenti,John.
The field of Genetics is undergoing tumultuous change after nearly a century of standard approaches to genetic analysis. The Human Genome Project is providing tools and technologies that are changing the ways that we pursue an understanding of gene function, which is the underlying goal in modern and traditional genetics. In this paper, I overview the directions of the genome project as they relate to gene function analysis in mice and humans, and how various modern technologies are coalescing to address this in a powerful way.
Tipo: Journal article
Palavras-chave: Gene expression; ESTs; Mutagenesis; Genome; Functional genomics.
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000100005

An evaluation of copper biosorption by a brown seaweed under optimized conditions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Antunes,Wallace M.; Luna,Aderval S; Henriques,Cristiane A; da Costa,Antonio Carlos A.
A basic investigation into the removal of copper ions from aqueous solutions by Sargassum sp. was conducted in batch conditions. The influence of different experimental parameters such as initial pH, shaking rate, sorption time, temperature, equilibrium conditions and initial concentrations of copper ions on copper uptake was evaluated. Results indicated that for shaking rates higher than 100 rpm no significant changes in copper accumulation were observed, as well as for pH values between 3.0 and 5.0. No marked effect on the biosorption of copper was detected for temperatures between 298 and 328K. The Langmuir model better represented the sorption process, in comparison to the model of Freundlich. The process followed a second-order kinetics and its...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300003

Formation of highly porous biodegradable scaffolds for tissue engineering
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mikos,Antonios G.; Temenoff,Johnna S.
In recent years, lack of donor organs has caused many to consider tissue engineering methods as means to replace diseased or damaged organs. This newly-emerging field uses tissue-specific cells in a three-dimensional organization, provided by a scaffolding material, to return functionality of the organ. For these applications, the choice of scaffolding material is crucial to the success of the technique. In addition to the chemical properties of the material, physical properties such as surface area for cell attachment are essential. Various methods of creating pores in these materials to increase surface area are reviewed here. Scaffolds formed using the different techniques, which include fiber bonding, solvent casting/particulate leaching, gas foaming...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000200003

Sodium azide mutagenesis resulted in a peanut plant with elevated oleate content
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Chuan Tang; Tang,Yue Yi; Wang,Xiu Zhen; Zhang,Shu Wei; Li,Gui Jie; Zhang,Jian Cheng; Yu,Shan Lin.
Screening of peanut seeds resulting from 0.39% sodium azide treatment with NIRS calibration equation for bulk seed samples identified a plant with more than 60% oleate. Oleate content in individual seeds of the plant, as predicted by NIRS calibration equation for intact single peanut seeds, ranged from 50.05% ~ 68.69%. Three seeds with &gt;60% oleate thus identified were further confirmed by gas chromatography. Multiple sequence alignments of the FAD2B gene from Huayu 22 (wild type) and peanut seeds with elevated oleate (mutant type) revealed a C281T transition in the coding region causing an I94T substitution in the oleoyl-PC desaturase, which may be responsible for reduction in the enzyme activity.
Tipo: Journal article
Palavras-chave: Chemical mutant; FAD2B; NIRS; Oleate; Peanut.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200010

Nucleotide sequence of a genomic clone encoding a cowpea (Vigna unguiculata L.) trypsin inhibitor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lawrence,Paulraj Kirubakaran; Nirmala,Jayaveeramuthu; Koundal,Kripa Ram.
A protease inhibitor gene has been isolated from native cowpea (Vigna unguiculata L.) cv. 130 from lambda-ZAP II genomic library. The nucleotide sequence of this genomic clone shared 86% homology with a cowpea trypsin inhibitor f IV mRNA, and 81% with Bowman-Birk protease inhibitor genes of soybean. The isolated gene had TATA and CAT signals in the 5' upstream region. The longest open reading frame had 504 bases, encoding 167 amino acids from the predicted coding region. The active serine centers of this protein was found between 105-158 amino acid residues, with a 69 amino acids long signal peptide in its N terminal. &lt;A NAME="Article"&gt;&lt;/A&gt;
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000100005

Establishment of an efficient callus induction and plant regeneration system in Pakistani wheat (Triticum aestivum) cultivars
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rashid,Umer; Ali,Shaukat; Ali,Ghulam Muhammad; Ayub,Najma; Masood,M. Shahid.
Four commercially grown wheat varieties of Pakistan, namely Inqilab-91, Chakwal-97, Tatara and Manthar were used for this investigation. For callus induction different concentrations of 2,4-Dichlorophenoxyaceticacid (2,4-D) along with 0.1 mg/L of Kinetin were evaluated. For regeneration initially different concentrations of Indole-3-Acetic Acid (IAA) and 6-BenzylAminoPurine (BAP) were tested. Best hormone combinations were further subjected to Kinetin and 6-&amp;#947;-&amp;#947;-dimethylallylaminopurine (2iP). For Inqilab-91, Chakwal-97 and Manthar, 3 mg/L of 2,4-D was found optimum, which induced 83.25%, 77.75% and 95.20% of embryogenic calli, respectively. Maximum callus induction (97.18%) was observed in Tatara when 2 mg/L of 2,4-D was used. As regard...
Tipo: Journal article
Palavras-chave: 2; 4-D 2iP BAP callus induction IAA kinetin regeneration wheat.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300004

A note on stability in food matrices of Salmonella enterica serovar Enteritidis-controlling bacteriophages
Provedor de dados: Electronic Journal of Biotechnology
Autores: Robeson,James; Turra,Gabriel; Huber,Karen; Borie,Consuelo.
Background Lytic bacteriophages are bacterial viruses that upon infection kill their host cells and therefore have re-emerged as biological control agents of bacterial pathogens, particularly in the field of food related infections. Here, we investigated the stability in different food matrices of five phage isolates capable of controlling the foodborne pathogen Salmonella enterica serovar Enteritidis (SE). Results We found that two phages, originally isolated from food sources, were up to 5 logs more stable than three phages isolated from sewage, in ten food matrices (fresh and processed) at both 4°C and 18°C. Conclusion Lytic phages isolated from contaminated food sources seem to be a better choice when structuring phage cocktails to be used in the...
Tipo: Journal article
Palavras-chave: Biocontrol; Foodstuffs; Phage.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000400008

Effect of pH in the survival of Lactobacillus salivarius strain UCO_979C wild type and the pH acid acclimated variant
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sanhueza,Enrique; Paredes-Osses,Esteban; González,Carlos L; García,Apolinaria.
Background Bacterial acclimation involves cellular changes permitting the survival of a microorganism to prolonged acid pH exposure. The general aim of this work is to support this idea by determining the effect of pH in the survival of the human gastric derived probiotic strain Lactobacillus salivarius UCO_979C-1 (wild type) and L. salivarius UCO_979C-2 (acclimation to pH 2.6), which possesses anti-Helicobacter pylori properties. Results To assess this aim, the exopolysaccharide production through the phenol-sulfuric acid method was evaluated. Moreover, morphological and structural changes by transmission and scanning electron microscopy were observed. The bacterial survival was measured by viable count. The results showed that the acclimated variant...
Tipo: Journal article
Palavras-chave: Acid stress; Acclimation; Lactobacillus salivarius.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500003

Methanogenic toxicity evaluation of chlortetracycline hydrochloride
Provedor de dados: Electronic Journal of Biotechnology
Autores: Reyes-Contreras,Carolina; Vidal,Gladys.
Background Anaerobic digestion is a technology applied successfully to converting organic matter into biogas. However, the presence of inhibitory compounds such as antibiotics can adversely affect methane production. The aim of this study is to evaluate the toxic effect of chlortetracycline hydrochloride (CLOR) on the methanogenic bacteria. In order to study the methanogenic toxicity of CLOR, different concentrations of CLOR (10, 50, 100, 200 mg L- 1) were evaluated by methanogenic toxicity assays using three feedings. Results Maximum methane production was obtained for the assays with 10 mg CLOR L- 1, the values obtained were 277 ± 4.07; 193 ± 11.31 and 166 ± 7.07 mL for the first, second and third feedings, respectively. The average values for acetic,...
Tipo: Journal article
Palavras-chave: Antibiotics; Anaerobic batch assay; Bacterial inhibition; Volatile fatty acids.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600010

Isolation and characterization of novel potent Cr(VI) reducing alkaliphilic Amphibacillus sp. KSUCr3 from hypersaline soda lakes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ibrahim,Abdelnasser S.S; El-Tayeb,Mohamed A; Elbadawi,Yahya B; Al-Salamah,Ali A.
A strain KSUCr3 with extremely high Cr(VI)-reducing ability under alkaline conditions was isolated from hypersaline soda lakes and identified as Amphibacillus sp. on the basis of 16S rRNA gene sequence analysis. The results showed that Amphibacillus sp. strain KSUCr3 was tolerance to very high Cr(VI) concentration (75 mM) in addition to high tolerance to other heavy metals including Ni2+ (100 mM), Mo2+ (75 mM), Co2+ (5 mM), Mn2+ (100 mM), Zn2+ (2 mM), Cu2+ (2 mM) and Pb (75 mM). Strain KSUCr3 was shown to be of a high efficiency in detoxifying chromate, as it could rapidly reduce 5 mM of Cr(VI) to a non detectable level over 24 hrs. In addition, strain KSUCr3 could reduce Cr(VI) efficiently over a wide range of initial Cr(VI) concentrations (1-10 mM) in...
Tipo: Journal article
Palavras-chave: Amphibacillus sp.; Bioremediation; Chromate reduction; Heavy metals; Soda lake.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400004

Engineering bacterial strains through the chromosomal insertion of the chlorocatechol catabolism tfdI CDEF gene cluster, to improve degradation of typical bleached Kraft pulp mill effluent pollutants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bobadilla,Roberto; Varela,Cristián; Céspedes,Ricardo; González,Bernardo.
Chloroaromatic pollutants from bleached Kraft pulp mill effluents (BKME) are difficult to degrade, because bacterial strains present in BKME aerobic treatments, only partially degrade these compounds, accumulating the corresponding chlorocatechol intermediates. To improve the catabolic performance of chlorocatechol-accumulating strains, we introduced, by chromosomal insertion, the tfdI CDEF gene cluster from Ralstonia eutropha JMP134 (pJP4). This gene cluster allows dechlorination and channelling of chlorocatechols into the intermediate metabolism. Two bacterial strains, R. eutropha JMP222 and Pseudomonas putida KT2442, able to produce chlorocatechols from 3-chlorobenzoate (3-CB) were used. Acinetobacter lwoffii RB2 isolated from BKME by its ability to...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200011

Production, purification and characterization of an ionic liquid tolerant cellulase from Bacillus sp. isolated from rice paddy field soil
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sriariyanun,Malinee; Tantayotai,Prapakorn; Yasurin,Patchanee; Pornwongthong,Peerapong; Cheenkachorn,Kraipat.
Background: Lignocellulosic biomass is a renewable, abundant, and inexpensive resource for biorefining process to produce biofuel and valuable chemicals. To make the process become feasible, it requires the use of both efficient pretreatment and hydrolysis enzymes to generate fermentable sugars. Ionic liquid (IL) pretreatment has been demonstrated to be a promising method to enhance the saccharification of biomass by cellulase enzyme; however, the remaining IL in the hydrolysis buffer strongly inhibits the function of cellulase. This study aimed to isolate a potential IL-tolerant cellulase producing bacterium to be applied in biorefining process. Result: One Bacillus sp., MSL2 strain, obtained from rice paddy field soil was isolated based on screening of...
Tipo: Journal article
Palavras-chave: Biorefinery; Cellulase; Ionic liquid; Lignocellulosic biomass.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000100004

Cloning, expression and characterization of the endoglucanase gene from Bacillus subtilis UMC7 isolated from the gut of the indigenous termite Macrotermes malaccensis in Escherichia coli
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wei,Kelvin Swee Chuan; Teoh,Teow Chong; Koshy,Philip; Salmah,Ismail; Zainudin,Arifin.
Background Bacillus subtilis UMC7 isolated from the gut of termite Macrotermes malaccensis has the ability to secrete a significant amount of extracellular endoglucanase, with an enzyme activity of 0.12 ± 0.01 &amp;#956;mol/min/mL. However, for economically viable industrial applications, the enzyme needs to be expressed in a heterologous host to overcome the low enzyme production from the wild-type strain. Results The endoglucanase gene from B. subtilis UMC7 was successfully cloned and expressed. A higher enzyme activity was observed in the intracellular fraction of the recombinant clone (0.51 ± 0.02 &amp;#956;mol/min/mL) compared with the cell-bound fraction (0.37 ± 0.02 &amp;#956;mol/min/mL) and the extracellular fraction (0.33 ± 0.01...
Tipo: Journal article
Palavras-chave: &amp;#946; -1 4-Endoglucanase Carboxyl-methylcellulose Extracellular enzyme activity Metal ions effect.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200007

RAPD and freezing resistance in Eucalyptus globulus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Fernández R.,Marta; Valenzuela A.,Sofía; Balocchi L.,Claudio.
Eucalyptus globulus is the second most important forest species in Chile, after Pinus radiata. The main advantages of E. globulus are its fast growth (25 m³/ha/year) and its excellent wood quality for kraft pulp production. On the negative side, its low freezing tolerance has been an obstacle for the expansion of plantations, specifically on the foothills of the Andes. The difference in the freezing resistance between clones of E. globulus has a genetic base and, therefore, it could be detected through DNA molecular markers. Fifteen clones of E. globulus, eight classified as freezing resistant and seven as freezing sensitive were analyzed using the technique of RAPD, in order to obtain molecular markers that could differentiate between freezing sensitive...
Tipo: Journal article
Palavras-chave: Eucalyptus globulus; Freezing resistance; Molecular markers; RAPD.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300025

Development of quantitative competitive PCR for determination of copy number and expression level of the synthetic glyphosate oxidoreductase gene in transgenic canola plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hadi,Faranak; Salmanian,Ali Hatef; Ghazizadeh,Elham; Amani,Jafar; Noghabi,Kambiz Akbari; Mousavi,Amir.
Background: For successful in vitro plant regeneration, plant cell lines with multiple transgene integration and low transgene expression levels need to be ruled out. Although real-time polymerase chain reaction (RT-PCR) is a rapid way to accomplish this, it is also expensive and typically limits the size of the target sequence. Quantitative competitive PCR (QC-PCR) is proven to be a safe and accurate method for determination of both copy number and quantification of transcript levels of synthetic transgenes in transformed plants. Results: The glyphosate oxidoreductase genewas chemically synthesized and used to transform Brassica napus L. via Agrobactrium-mediated transformation. A construct containing the mutated form of a synthetic glyphosate...
Tipo: Journal article
Palavras-chave: Brassica napus L.; Competitive quantitative PCR; Transcript level; Transgene copy number.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000400002

The crustacean selenoproteome similarity to other arthropods homologs: A mini review
Provedor de dados: Electronic Journal of Biotechnology
Autores: García-Triana,Antonio; Yepiz-Plascencia,Gloria.
Selenoproteins (Sels) are involved in oxidative stress regulation. Glutathione peroxidase (GPx) and thioredoxin reductase are among the most studied Sels in crustaceans. Since their expressions and activities are affected by pathogens, environmental and metabolic factors, their functions might be key factors to orchestrate the redox cellular balance. The most studied invertebrate selenoproteome is from Drosophila. In this fly, SelD and SelB are involved in selenoproteins synthesis, whereas SelBthD, SelH and SelK are associated with embryogenesis and animal viability. None of the Sels found in Drosophila have been identified in marine crustaceans yet, and their discovery and function identification is an interesting research challenge. SelM has been...
Tipo: Journal article
Palavras-chave: Functions; Invertebrates; Redox; Selenoproteins.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500017

Selection of white-rot fungi to formulate complex and coated pellets for Reactive Orange 165 decolourization
Provedor de dados: Electronic Journal of Biotechnology
Autores: Elgueta,Sebastián; Rubilar,Olga; Lima,Nelson; Diez,M. Cristina.
Six strains of white-rot fungi isolated from southern Chile were evaluated for their ergosterol/biomass correlation and ligninolytic potential in solid medium to formulate pellets for Reactive Orange 165 (RO165) decolourization. The fungus Anthracophyllum discolor was selected to formulate complex pellets (fungal mycelium, sawdust, and activated carbon), coated pellets (complex pellet + alginate) and simple pellets (fungal mycelium). The activity of ligninolytic enzymes (laccase, manganese peroxidase, manganese-independent peroxidase, and lignin peroxidase) was evaluated in both the complex and coated pellets in modified Kirk medium, and the morphology of the pellets was studied using scanning electron microscopy (SEM). Complex pellets of A. discolor...
Tipo: Journal article
Palavras-chave: Complex pellets; Ligninolytic enzymes; RO165 decolourization; White-rot fungi.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600008

Analysis of diversity among six populations of Colombian mango (Mangifera indica L. cvar. Hilacha) using RAPDs markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Díaz-Matallana,Marcela; Schuler-García,Ingrid; Ruiz-García,Manuel; Hodson de Jaramillo,Elizabeth.
Currently in Colombia, there are only records of morph-agronomic characterizations of Mangifera indica cvar. Hilacha; molecular studies on this mango variety have not been carried out. The aim of this work was to identify the genetic diversity of six populations of mango Hilacha by RAPDs markers, as a fundamental base for breeding programs, conservation and selection of promissory materials for the fruit industry at the national level. From 60 primers evaluated in the populations, five primers were selected and were launched in the six populations. Polymorphic bands of RAPDs were transformed into binary matrices, which were then processed with NTSYS-PC, POPGENE and TFPGA softwares. The overall genetic diversity, H T = 0.468 ± 0.0016, is very similar to the...
Tipo: Journal article
Palavras-chave: Genetic variability; Mango Hilacha; Organoleptic quality; RAPDs.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300001

Strategies to capture biotechnology opportunities in Chile
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cuevas,Cristian Hernandez; Valenzuela,Pablo D. T.
Two complementary strategies are proposed to help develop the biotechnology industry in Chile. The objectives of such propositions are based on identifying business opportunities, which can be transformed into biotechnology projects that complement the competitive advantages of the most active areas of the Chilean economy. As a result, the establishment of these initiatives may create the proper business environment where good information, investors&amp;rsquo; safeguards and economic incentives would be provided to encourage investors to support new biotechnology ventures focused on mining, aquaculture, forestry, as well as wine and fruit production. In addition, a complete description of the Chilean biotechnology industry is provided. Amongst other...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200010

Copper-induced adaptation, oxidative stress and its tolerance in Aspergillus niger UCP1261
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cavalcanti Luna,Marcos A; Rodrigues Vieira,Edson; Okada,Kaoru; Campos-Takaki,Galba Maria; do Nascimento,Aline Elesbão.
Background The effects of exposure to copper, during growth, on the production of biomass, total protein, catalase, glutathione-S transferase, glutathione peroxidase, peroxidase, polyphosphate, acid and alkaline phosphatases, ultrastructure and the ability to remove this metal from Aspergillus niger, obtained from caatinga soil, were evaluated. Results All parameters tested were influenced by the concentration of metal in the culture medium. The presence of metal induced high levels of antioxidant enzymes, including lipid peroxidation, thereby revealing the appearance of an oxidative stress response. The variation in polyphosphate levels indicates the participation of the polymer in response to stress induced by copper. The activities of the phosphatases...
Tipo: Journal article
Palavras-chave: Aspergillus niger; Antioxidant enzyme; Copper removal; Polyphosphate; Ultrastructure.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600006

Feasibility study of organic matter and Ammonium removal using loofa sponge as a supporting medium in an aerated submerged fixed-film reactor (ASFFR)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Nabizadeh,Ramin; Naddafi,Kazem; Mesdaghinia,Alireza; Nafez,Amir Hosien.
Biofilm systems are efficient in the removal of organic matter and ammonium from wastewaters. In this study, loofa sponge, a natural product, was used as a supporting medium in an aerated submerged fixed-film reactor to evaluate its performance in removing organic matter and nitrogen from wastewater. Four pilot runs were performed with chemical oxygen demand (COD) concentrations of 100, 200, 300 and 400 mg l-1 to provide an organic loading rate of 0.6, 1.2, 1.8, and 2.4 kg m-3d-1 respectively. In these pilot runs, the influent ammonium nitrogen concentrations were justified to 5, 10, 15 and 20 mg l-1 as N to provide an influent nitrogen loading of 30, 60, 90 and 120 g m-3.d-1 respectively. Although soluble COD removal efficiency greater than 80 percent was...
Tipo: Journal article
Palavras-chave: Aerated submerged fixed-film reactor; Biofilm; Fixed-Film; Loofa; Organic matter removal; Sponge.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400006

EDITORIAL
Provedor de dados: Electronic Journal of Biotechnology
Autores: Marshall,Sergio.
Tipo: Journal article
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500011

Single nucleotide polymorphisms in partial sequences of the gene encoding the large sub-units of ADP-glucose pyrophosphorylase within a representative collection of 10 Musa genotypes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mahendhiran,Muhilan; Ramirez-Prado,Jorge Humberto; Escobedo-Gracia Medrano,Rosa Maria; Canto-Canché,Blondy; Tzec-Simá,Miguel; Grijalva-Arango,Rosa; James-Kay,Andrew.
Background ADP-glucose pyrophosphorylase (AGPase) is a rate-limiting enzyme catalyzing the first step in the starch biosynthesis pathway in higher plants. To date, there are no reported variants or isoforms of the AGPase enzyme in bananas (Musa spp. family Musaceae) as is the case of other plants. In this study, genomic DNA sequences homologous to the gene encoding one of the large subunits of the enzyme were amplified from 10 accessions of the genus Musa, including representatives of wild ancestors (AA and BB genomes), dessert bananas (AA, AAA, AB and AAB genomes), plantains (AAB genome) and cooking bananas (ABB and AAA genomes), and studied in order to find single nucleotide polymorphisms (SNP) base variations in Musa accessions. Results In the 810-base...
Tipo: Journal article
Palavras-chave: Haplotypes; Starch metabolism enzyme; Variants.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000300006

Genetic diversity of breeding popcorn lines determined by SSR markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ribeiro Trindade,Ana Paula; Barth Pinto,Ronald José; Amaral Júnior,Antonio Teixeira do; Mangolin,Claudete Aparecida; Silva Machado,Maria de Fátima Pires da; Scapim,Carlos Alberto.
Information about genetic dissimilarity is very important to corroborate genealogical relationships and to predict the most heterozygotic hybrid combinations. Eight popcorn S6 lines of diverse germplasm types were evaluated using simple sequence repeats (SSR) markers. Of a total of 51 evaluated polymorphic primers, 15 were used for polymerase chain reaction (PCR) amplification. The genetic distance was estimated by Rogers&amp;#8217; modified distance. The different popcorn breeding programs in Brazil are possibly using highly similar base-populations. The genetic similarity of lines P1-3 and P8-1 was lowest, while P3-3 and P8-2 were genetically more similar. The cophenetic correlation showed that the Unweighted Pair-Group Method Using Arithmetic Averages...
Tipo: Journal article
Palavras-chave: Advanced generations; Genetic variability; Molecular markers; Zea mays.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100004

High-yield production of the human lysozyme by Pichia pastoris SMD1168 using response surface methodology and high-cell-density fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yu,Ying; Zhou,Xiaoyu; Wu,Sheng; Wei,Tiantian; Yu,Long.
Background Lysozyme plays a crucial role in innate immunity with its well-recognized bacteriolytic activity. In this study, the influence of expression parameters (inoculation volume, culture volume, growth time, induction temperature and time, initial pH and methanol concentration) on human lysozyme (HLZ) production in recombinant P. pastoris SMD1168 was investigated through Plackett-Burman (PB) design and response surface methodology (RSM). Results It was revealed that induction temperature, induction time and culture volume had significant influence (P &lt; 0.01) on HLZ expression level, which were elected for further optimization with three-dimensional response surface designs for enhanced HLZ production. The highest lysozyme activity reached 3301 U/mL...
Tipo: Journal article
Palavras-chave: Expression optimization; LYZ; Plackett-Burman design; RSM.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600009

Cinnamic acid, ethanol and temperature interaction on coumarate decarboxylase activity and the relative expression of the putative cd gene in D. bruxellensis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ganga,María Angélica; Salinas,Francisco; Ravanal,Cristina; García,Verónica; Carrasco,Carolina; Martínez,Claudio; Saavedra,Jorge.
Dekkera bruxellensis is one of the main contaminating yeasts in wine due to its ability to metabolize cinnamic acids into volatile phenols. This yeast metabolizes p-coumaric acid into 4-vinylphenol through a coumarate decarboxylase (CD) and then transforms it into to 4-ethylphenol (EF) through a vinylphenol reductase. In this work we investigated the influence of the interaction between the concentration of p-coumaric acid, ferulic acid and ethanol as well as growth temperature on the production of CD activity and the expression of a putative gene that codes for this enzymatic activity. For this, a Box Behnken experimental design was used. The concentration of p-coumaric acid (5-26 ppm) and ferulic acid (3-9 ppm) alone did not show any significant effect...
Tipo: Journal article
Palavras-chave: Dekkera/Brettanomyces; Cinnamic acids; Coumarate decarboxylase; Off-flavours; Wine.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500002

Response surface methodology based optimization for degradation of align in Laminaria japónica feedstuff via fermentation by Bacillus in Apostichopus japónicas farming
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Xitao; Wang,Lili; Li,Xiaoyu; Xu,Yongping.
Background: The alga Laminaria japonica is the most economically important brown seaweed cultured in China, which is used as food and aquatic animal feedstuff. However, the use of L. japonica as a feedstuff in Apostichopus japonicasfarming is not ideal because A. japonicas does not produce enough enzyme activity for degrading the large amount of algin present in L. japonica. In this study, semi solid fermentation of the L. japonica feedstuff employing a Bacillus strain as the microbe was used to as a mean to degrade the algin content in L. japonica feedstuff. Results: The Bacillus strain, Bacillus amyloliquefaciens WB1, was isolated by virtue of its ability to utilize sodium alginate as the sole carbon source. Eight factors affecting growth and...
Tipo: Journal article
Palavras-chave: Align; Bacillus amyloliquefaciens; Central-Composite Design; Plackett-Burman design; Sea cucumber.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400001

Codon optimization of 1,3-propanediol oxidoreductase expression in Escherichia coli and enzymatic properties
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Wei; Ng,I-Son; Fang,Baishan; Yu,Jincong; Zhang,Guangya.
The gene dhaT from Klebsiella pneumoniae encoding 1,3-propanediol oxidoreductase (PDOR) was de novo synthesized by splicing overlap extension polymerase chain reaction (SOE-PCR) primarily according to Escherichia coli’s codon usage, as well as mRNA secondary structure. After optimization, Codon Adaptation Index (CAI) value was improved from 0.75 to 0.83, meanwhile energy of mRNA secondary structure was increased from -400.1 to -86.8 kcal/mol. This synthetic DNA was under control by phage T7 promoter in the expression vector pET-15b and transformed into the E. coli BL21 (DE3) strain. Inducers such as isopropyl &amp;#946;-D-thiogalactoside (IPTG) and lactose were compared by activity at different inducing time. The activity of PDOR after codon optimized was...
Tipo: Journal article
Palavras-chave: 1; 3-propanediol oxidoreductase codon optimization enzymatic properties Escherichia coli overlap extension PCR.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400007

Use of AFLP markers to estimate molecular diversity of Phakopsora pachyrhizi
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lourdes Rocha,Carla Maria; Vellicce,Gabriel Ricardo; García,María Gabriela; Pardo,Esteban Mariano; Racedo,Josefina; Perera,María Francisca; de Lucía,Adrian; Gilli,Javier; Bogado,Noelia; Bonnecarrère,Victoria; German,Silvia; Marcelino,Francismar; Ledesma,Fernando; Reznikov,Sebastián; Ploper,Leonardo Daniel; Welin,Bjorn; Castagnaro,Atilio Pedro.
Background Asian soybean rust (SBR) caused by Phakopsora pachyrhizi Syd. &amp;amp; Syd., is one of the main diseases affecting soybean and has been reported as one of the most economically important fungal pathogens worldwide. Knowledge of the genetic diversity of this fungus should be considered when developing resistance breeding strategies. We aimed to analyze the genetic diversity of P. pachyrhizi combining simple sampling with a powerful and reproducible molecular technique. Results We employed Amplified Fragment Length Polymorphism (AFLP) technique for the amplification of P. pachyrhizi DNA extracted from naturally SBR-infected plants from 23 production fields. From a total of 1919 markers obtained, 77% were polymorphic. The high percentage of...
Tipo: Journal article
Palavras-chave: Asian soybean rust; Genetic variation; Glycine max; Molecular markers.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600009

Using a neural network to backtranslate amino acid sequences
Provedor de dados: Electronic Journal of Biotechnology
Autores: White,Gilbert; Seffens,William.
A neural network (NN) was trained on amino and nucleic acid sequences to test the NN’s ability to predict a nucleic acid sequence given only an amino acid sequence. A multi-layer backpropagation network of one hidden layer with 5 to 9 neurons was used. Different network configurations were used with varying numbers of input neurons to represent amino acids, while a constant representation was used for the output layer representing nucleic acids. In the best-trained network, 93% of the overall bases, 85% of the degenerate bases, and 100% of the fixed bases were correctly predicted from randomly selected test sequences. The training set was composed of 60 human sequences in a window of 10 to 25 codons at the coding sequence start site. Different NN...
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000300009

Ethanol production from sweet sorghum juice under very high gravity conditions: Batch, repeated-batch and scale up fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Nuanpeng,Sunan; Laopaiboon,Lakkana; Srinophakun,Penjit; Klanrit,Preekamol; Jaisil,Prasit; Laopaiboon,Pattana.
Batch ethanol fermentations from sweet sorghum juice by Saccharomyces cerevisiae NP 01 were carried out in a 500 ml air-locked Erlenmeyer flask under very high gravity (VHG) and static conditions. The maximum ethanol production efficiency was obtained when 9 g l-1 of yeast extract was supplemented to the juice. The ethanol concentration (P), productivity (Qp) and yield (Yp/s) were 120.24 ± 1.35 g l-1, 3.01 ± 0.08 g l-1 h-1 and 0.49 ± 0.01, respectively. Scale up ethanol fermentation in a 5-litre bioreactor at an agitation rate of 100 rev min-1 revealed that P, Qp and Yp/s were 139.51 ± 0.11 g l-1, 3.49 ± 0.00 g l-1 h-1 and 0.49 ± 0.01, respectively, whereas lower P (119.53 ± 0.20 g l-1) and Qp (2.13 ± 0.01 g l-1 h-1) were obtained in a 50-litre bioreactor....
Tipo: Journal article
Palavras-chave: Batch; Ethanol fermentation; Repeated-batch; Scale up; Sweet sorghum; VHG.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100004

Mechanisms and roles of the RNA-based gene silencing
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jana,Snehasis; Chakraborty,Chiranjib; Nandi,Shyamsundar.
RNA silencing is a remarkable type of gene regulation. This process has been found to occur in many different organisms such as plants (co-suppression), fungi (quelling), and animals (RNA interference; RNAi). Double-stranded RNA (dsRNA) is a potent trigger in RNA silencing mechanisms operating in a wide range of organisms. This mechanism recognizes dsRNA and processes them into small 21-25nt RNAs (smRNAs). Small RNAs can guide post-transcriptional degradation of complementary messenger RNAs and in plants, transcriptional gene silencing is occurred by methylation of homologous DNA sequences. In plants, it serves as an antiviral defense, and many plant viruses encode suppressors of silencing such as helper component-proteinase of potyviruses (HC-Pro) and the...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300015

Biofilm formation for organic matter and sulphate removal in gas-lift reactors
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pizarro,Carolina; Donoso-Bravo,Andrés; Jeison,David; Ruiz-Filippi,Gonzalo; Chamy,Rolando.
A start-up strategy was presented and evaluated to obtain a well-established biofilm in a gas lift-reactor capable both for the removal of organic matter and sulphate. Pumice stone was used as material support. The influence of shear forces, given by the biogas recirculation, the effect of the COD/SO4-2 ratio and the OLRs increase were evaluated on the reactor performance. From the first stages, cell colonization was observed along with the presence of extracellular polymeric substances. The COD and sulphate removal was over 70%, for all conditions. The increase of gas flow did not have an adverse effect on biofilm development even though there was some detachment. Specific methanogenic activity of the biofilm increased along the experiments. Operational...
Tipo: Journal article
Palavras-chave: Anaerobic biofilm; Gas-lift reactors; Sulphate; Start-up.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400003

Efficient expression and characterization of a cold-active endo-1, 4-&amp;#946;-glucanase from Citrobacter farmeri by co-expression of Myxococcus xanthus protein S
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bai,Xi; Yuan,Xianjun; Wen,Aiyou; Li,Junfeng; Bai,Yunfeng; Shao,Tao.
Background: Cold-active endo-1, 4-&amp;#946;-glucanase (EglC) can decrease energy costs and prevent product denaturation in biotechnological processes. However, the nature EglC from C. farmeri A1 showed very low activity (800 U/L). In an attempt to increase its expression level, C. farmeri EglC was expressed in Escherichia coli as an N-terminal fusion to protein S (ProS) from Myxococcus xanthus. Results: A novel expression vector, pET(ProS-EglC), was successfully constructed for the expression of C. farmeri EglC in E. coli. SDS-PAGE showed that the recombinant protein (ProS-EglC) was approximately 60 kDa. The activity of ProS-EglC was 12,400 U/L, which was considerably higher than that of the nature EglC (800 U/L). ProS-EglC was active at pH 6.5-pH 8.0,...
Tipo: Journal article
Palavras-chave: Cellulose degradation; Cellulose; Cold-active enzyme; Endoglucanases; Enzymatic properties; Escherichia coli; Expression; Novel expression vector; N-terminal fusion; Protein S-tag; Recombinant protein.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600012

DNA sequence variation of drought-response candidate genes in Austrocedrus chilensis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pomponio,María F; Torales,Susana; Gallo,Leonardo A; Pastorino,Mario J; Marchelli,Paula; Cervera,María Teresa; Poltri,Susana Marcucci.
Background: Austrocedrus chilensis (D. Don) Pic. Ser. et Bizzarri commonly known as Patagonian cypress is a member of the Cupressaceae family, characterized by a high adaptive potential for growing in marginal areas and good timber quality. The species grows over a wide area and under a wide range of rainfall. This study assessed adaptive genetic variation at SNP level in candidate genes involved in response to drought stress. Results: A total of 18 single nucleotide polymorphisms (SNPs) were found among 1,428 bp. Average nucleotide diversity value (&amp;#960; = 0.00312) was similar to those previously reported in other Cupressaceae. The Fst average among genes and populations was 0.163 and the lowest differentiation was observed in continuous and humid...
Tipo: Journal article
Palavras-chave: Adaptive variation; Balancing selection; Patagonian cypress; Single nucleotide polymorphisms (SNPs).
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000200003

Intein-mediated expression of cecropin in Escherichia coli
Provedor de dados: Electronic Journal of Biotechnology
Autores: Díaz,Mauricio; Venturini,Elena; Marchetti,Stefano; Arenas,Gloria; Marshall,Sergio H.
Different strategies have been used to overcome the difficulties to produce antimicrobial peptides. Here we used Intein Mediated Purification with an Affinity Chitin-binding Tag (IMPACT-System, New England Biolabs) for the expression of the antimicrobial peptide cecropin to reduce its sensitivity to intracellular proteases and use its inducible self-cleaving capability to remove the carrier. Cecropin was cloned into suitable expression vector pTYB11, and expression induced by IPTG in Escherichia coli ER2566. The use of 22ºC induction allowed the expression of cecropin with its intein carrier in soluble form. Cell extracts were purified by chitin affinity chromatography and intein-mediated splicing of the target protein was achieved by thiol addition,...
Tipo: Journal article
Palavras-chave: Antimicrobial; Cecropin; Fusion; Intein; Peptide; Soluble.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000200003

Biodegradation of deproteinized potato wastewater and glycerol during cultivation of Rhodotorula glutinis yeast
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kot,Anna Maria; Blazejak,Stanislaw; Kurcz,Agnieszka; Gientka,Iwona.
Background Deproteinized potato wastewater and glycerol are two by-products which are difficult to dispose. The objective of this study was to determine the ability of Rhodotorula glutinis to use glycerol and nitrogen compounds present in deproteinized potato wastewater and to evaluate the ability of simultaneous biodegradation of potato wastewater and glycerol via microbiological methods. Results It has been found that R. glutinis used glycerol and potato wastewater as a source of carbon and nitrogen, respectively. The highest degree of glycerol content (70.6%) reduction was found after cultivation of the investigated strain using a medium with 5% glycerol. In this medium, a significant reduction in the total protein content, estimated at 61%, was...
Tipo: Journal article
Palavras-chave: Biodegradation; Chemical oxygen demand; Industrial waste; Rhodotorula.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600007

Generation and analysis of an Eucalyptus globulus cDNA library constructed from seedlings subjected to low temperature conditions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rasmussen-Poblete,Susana; Valdes,Jorge; Gamboa,Maria Cecilia; Valenzuela,Pablo D.T; Krauskopf,Erwin.
Eucalyptus globulus is the most important commercial temperate hardwood in the world because of its wood properties and due to its characteristics for biofuel production. However, only a very low number of expressed sequence tags (ESTs) are publicly available for this tree species. We constructed a cDNA from E. globulus seedlings subjected to low temperature and sequenced 9,913 randomly selected clones, generating 8,737 curated ESTs. The assembly produced 1,062 contigs and 3,879 singletons forming a Eucalyptus unigene set. Based on BLASTX analysis, 89.3% of the contigs and 88.5% of the singletons had significant similarity to known genes in the non-redundant database of GenBank. The Eucalyptus unigene set generated is a valuable public resource that...
Tipo: Journal article
Palavras-chave: Cellulose; Cold-temperature; EST database; Forest biotechnology; Lignin.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200008

Fermentation optimization of maltose-binding protein fused to neutrophil-activating protein from Escherichia coli TB1
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lu,Jike; Song,Qi; Ji,Zhenyu; Liu,Xin; Wang,Ting; Kang,Qiaozhen.
Background The fermentation conditions of recombinant maltose-binding protein fused to neutrophil-activating protein (rMBP-NAP) of Helicobacter pylori were optimized from Escherichia coli TB1 with varying medium, inoculum age and size, time, inducer, pH and temperature in batch fermentation. Results It was revealed that the optimal conditions for the production of rMBP-NAP in shake flask were as follows: M9 medium (with 3% yeast extract powder added), inoculum age of 19 h, inoculum size of 6%, initial pH of 6.6, temperature of 37°C, and 0.7 mmoL/L IPTG inducted 21 h in a 50 mL/250 mL shake flask. The recombinant protein yield was increased from 59 to 592 mg/L after optimization. Fermentation process conducted in a 10 L fermenter with similar conditions...
Tipo: Journal article
Palavras-chave: Escherichia coli; Fermentation; Optimization; Recombinant protein.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400004

Development of trinucleotide (GGC)n SSR markers in peanut (Arachis hypogaea L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yuan,Mei; Gong,Limin; Meng,Ronghua; Li,Shuangling; Dang,Phat; Guo,Baozhu; He,Guohao.
Cultivated peanut (Arachis hypogaea L.) is an oilseed crop of economic importance. It is native to South America, and it is grown extensively in the semi-arid tropics of Asia, Africa, and Latin America. Given an extremely narrow genetic base, efforts are being made to develop simple sequence repeat (SSR) markers to provide useful genetic and genomic tools for the peanut research community. A SSR-enriched library to isolate trinucleotide (GGC)n SSRs in peanut was constructed. A total of 143 unique sequences containing (GGC)n repeats were identified. One hundred thirty eight primer pairs were successfully designed at the flanking regions of SSRs. A suitable polymerase was chosen to amplify these GC-rich sequences. Although a low level of polymorphism was...
Tipo: Journal article
Palavras-chave: Cultivated peanut; Microsatellites; Polymorphism; Simple sequence repeat.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600005

Anaerobic membrane bioreactors: Are membranes really necessary?
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jeison,David; Díaz,Israel; van Lier,Jules B.
Membranes themselves represent a significant cost for the full scale application of anaerobic membrane bioreactors (AnMBR). The possibility of operating an AnMBR with a self-forming dynamic membrane generated by the substances present in the reactor liquor would translate into an important saving. A self-forming dynamic membrane only requires a support material over which a cake layer is formed, which determines the rejection properties of the system. The present research studies the application of self-forming dynamic membranes in AnMBRs. An AnMBR was operated under thermophilic and mesophilic conditions, using woven and non woven materials as support for the dynamic membranes. Results showed that the formation of a cake layer over the support materials...
Tipo: Journal article
Palavras-chave: Cake layer; Dynamic membrane; MBR; Woven filter.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400001

Genetic instability and oral cancer
Provedor de dados: Electronic Journal of Biotechnology
Autores: Park,No-Hee; Kang,Mo K.
Development of oral cancer proceeds through discrete molecular genetic changes that are acquired from the loss of genomic integrity after continued exposure to environmental risk factors. Of particular importance in oral cancer development are tobacco-related chemical carcinogens and human papillomavirus (HPV) infection. To understand the mechanisms by which these risk factors contribute to tumorigenesis, we developed an in vitro model of sequential, multistep oral carcinogenesis model of normal human oral keratinocytes (NHOK) by immortalizing these cells with cloned "high risk" HPV genome. HPV viral genome alone failed to give rise to a tumorigenic cell population, which required further exposure to chemical carcinogens. HPV-immortalized cells exhibited...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000100005

Ceftiofur-loaded PHBV microparticles: A potential formulation for a long-acting antibiotic to treat animal infections
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vilos,Cristian; Constandil,Luis; Herrera,Natalia; Solar,Paula; Escobar-Fica,Jorge; Velásquez,Luis Alberto.
Background: The infectious diseases in the livestock breeding industry represent a significant drawback that generates substantial economic loss and have led to the indiscriminate use of antibiotics. The formulation of polymeric microparticles loaded with antibiotics for veterinary use can: reduce the number of required doses; protect the drug from inactivation; and maintain a sustained-release of the antibiotic drug at effective levels. Accomplishing all of these goals would have a significant economic and animal health impact on the livestock breeding industry. Results: In this work, we formulated ceftiofur-loaded PHBV microparticles (PHBV-CEF) with a spherical shape, a smooth surface and diameter sizes between 1.65 and 2.37 &amp;#956;m. The...
Tipo: Journal article
Palavras-chave: Ceftiofur; Drug delivery; Livestock breeding industry; PHBV; Polymeric microparticles.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000400001

EST sequencing and SSR marker development from cultivated peanut (Arachis hypogaea L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Song,Guo Qi; Li,Meng Jun; Xiao,Han; Wang,Xing Jun; Tang,Rong Hua; Xia,Han; Zhao,Chuan Zhi; Bi,Yu Ping.
Making use of the gene resources of wild type peanuts is a way to increase the genetic diversity of the cultivars. Marker assisted selection (MAS) could shorten the process of inter-specific hybridization and provide a possible way to remove the undesirable traits. However, the limited number of molecular markers available in peanut retarded its MAS process. We started a peanut ESTs (Expressed Sequence Tags) project aiming at cloning genes with agronomic importance and developing molecular markers. In this study we found 610 ESTs that contained one or more SSRs from 12,000 peanut ESTs. The most abundant SSRs in peanut are trinucleotides (66.3%) SSRs and followed by dinucleotide (28.8%) SSRs. AG/TC (10.7%) repeat was the most abundant and followed by CT/GA...
Tipo: Journal article
Palavras-chave: Arachis hypogaea L.; Cultivars; EST-SSR; Polymorphism; Wild-type peanut.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300007

Effects of biosorption parameter: kinetics, isotherm and thermodynamics for Ni(II) biosorption from aqueous solution by Circinella sp.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Alpat,Senol; Alpat,Sibel Kilinç; Çadirci,Bilge Hilal; Özbayrak,Özge; Yasa,Ihsan.
Circinella sp. was employed as a biosorbent for removal of Ni(II) from aqueous solution. The biosorption kinetics and isotherms were investigated. The effect of several parameters, such as biosorbent dosage, contact time, initial concentration, pH and temperature, on biosorption process was evaluated. The kinetic studies indicated that the biosorption followed pseudo-second order kinetic model. Biosorption behaviour of Ni(II) on Circinella sp. was expressed by both Langmuir and Freundlich isotherms. The equilibrium data fit better to the Langmuir model compared to the Freundlich model in concentration range studied (1.0-3.0 mM). The thermodynamic parameters (&amp;#916;G0, &amp;#916;H0 and &amp;#916;S0) were also determined, and it was found that the Ni(II)...
Tipo: Journal article
Palavras-chave: Biosorption; Circinella sp; Equilibrium; Kinetic; Nickel.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500004

Genotypic variation of Agrobacterium-mediated transformation of Italian ryegrass
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lee,Ki-Won; Choi,Gi Jun; Kim,Ki-Yong; Yoon,Sei Hyung; Ji,Hee Chung; Park,Hyung Soo; Lim,Young Chul; Lee,Sang-Hoon.
In the present study, genotypic variation of Agrobacterium-mediated transformation of Korean Italian ryegrass has been evaluated. Mature seed-derived calli of seven cultivars were inoculated and co-cultured with Agrobacterium tumefaciens carrying the binary vector pCAMBIA1301, which contains a reporter gene (gus) and a plant selectable marker gene conferring resistance to hygromycin (hpt) in the T-DNA region. The effects of several factors such as callus type and callus age on transformation effectiveness and the expression of the GUS gene were investigated. The highest transformation effectiveness (6.7%) was obtained with the Hwasan 101 cultivar when 9-week-old calli (type-I) were inoculated with Agrobacterium. The overall transformation rates of the...
Tipo: Journal article
Palavras-chave: Agrobacterium; Forage crop; Italian ryegrass; Transgenic plants.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300008

Breeding of high lipid producing strain of Geotrichum robustum by ion beam implantation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cao,Yuanyuan; Yao,Jianming; Li,Jun; Chen,Xiangsong; Wu,Jinyong.
To obtain an industrial strain with high lipid yield, the wild strain G0 of Geotrichum robustum was mutated by means of nitrogen ions implantation. Mutagenic effects of strain G0 by low energy N+ ion implantation were studied. The experimental results indicated that the survival rate curve took a ?saddle? shape, and the positive mutation rate was increased to 22.00% at the dose of nitrogen ions 2.0 x 10(15) ions/cm² when the survival rate was 28.60%. By repeated screening, a high lipid producing strain G9 was obtained. The biomass, lipid content and lipid yield of the mutant can reach 40.25 g/L, 71.14% and 28.63 g/L after cultured in a 5L fermenter for 8 days, increasing by 52.81%, 68.82% and 157.93% to those of wild strain, respectively. Analysis results...
Tipo: Journal article
Palavras-chave: Fatty acids; Geotrichum robustum; High lipid producing strain; Ion beam implantation.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600002

Growth and antibacterial activity of Lentinula edodes in liquid media supplemented with agricultural wastes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hiroko Hassegawa,Regina; Megumi Kasuya,Maria Catarina; Dantas Vanetti,Maria Cristina.
Antibacterial activity of Lentinula edodes against Bacillus subtilis was evaluated in cell-free filtrates obtained after growth in 14 different culture media. The highest B. subtilis growth inhibition was promoted by filtrates of growth media supplemented with rice bran, vermiculite or molasses. L. edodes dry mycelial biomass in liquid culture with 0.5% added rice bran was 3.2 mg/ml, after growth for 30 days at 25&amp;ordm;C without shaking, and 4.3 mg/ml under orbital shaking (150 rpm). However, antibacterial activity, detected between 20 and 24 days of incubation of stationary cultures, was absent in filtrates of aerated cultures. Temperatures of 20-25&amp;ordm;C enhanced both growth and antibacterial activity. Optimum pH for L. edodes mycelial growth...
Tipo: Journal article
Palavras-chave: Bacterial inhibition; Bioconversion; Mycelial growth; Mushroom; Shiitake.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200011

Selection of Arthrospira platensis strains with productivity in brackish water with high boron levels for commercial production in the Lluta Valley
Provedor de dados: Electronic Journal of Biotechnology
Autores: Oxa,Patricio; Bastías,Elizabeth; Uribe,Eduardo.
Adaptation and selection of Arthrospira platensis strains, for cultivation in brackish water with excess boron (B) in the Lluta Valley can become an interesting alternative that would allow to extend these cultures to areas that possess the environmental conditions, but that lack the fresh water needed to do it. Strains TX98 and P88 were evaluated in laboratory conditions with three different media of brackish water and with the white medium, the Zarrouk modified medium (MZM). The growing media with brackish water with a B concentration present in the Lluta River of 20 mgL-1 (B20) and medium with 30 mgL-1 (B30), and 10 mg L-1 of B (B10). The effect of the different media on the growing parameters with a culture temperature of 25 ± 1ºC in the three...
Tipo: Journal article
Palavras-chave: Brackish water; Boron; Growth medium; Microalgae; Spirulina (Arthrospira).
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500019

Efficient protocol for isolation of functional RNA from different grape tissue rich in polyphenols and polysaccharides for gene expression studies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vasanthaiah,Hemanth K.N.; Katam,Ramesh; Sheikh,Mehboob B.
Extraction of RNA from plant tissue containing high levels of polyphenols and polysaccharides is tedious and difficult in grapes. Although several protocols have been published for plant RNA isolation, most have failed to yield high quality RNA in sufficient quantity from mature and diseased grape tissue. We describe a protocol for isolating intact and high quality RNA from various grape tissues as evident by high A260/A280 absorbance ratio (1.8 to 1.9) and electrophoretic profile on denaturing formaldehyde agarose gel. On an average, 205 µg RNA per g of fresh tissue were obtained using this modified protocol. RNA quality was further assessed through RT-PCR, differential display RT-PCR and subtractive hybridization, and found to be suitable for molecular...
Tipo: Journal article
Palavras-chave: Differential display RT-PCR; Grape; RNA isolation; RT-PCR; Subtractive hybridization; Vitis.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300005

Bioconversion and saccharification of some lignocellulosic wastes by Aspergillus oryzae ITCC-4857.01 for fermentable sugar production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Begum,Most. Ferdousi; Alimon,Abdul Razak.
The recent interest in bioconversion of agricultural and industrial wastes to chemical feedstock has led to extensive studies on cellulolytic enzymes produced by microorganisms. In the present study three lignocellulosic substrates viz. sugarcane bagasse, sawdust and water hyacinth were pre-treated with alkali and enzyme and their effect on bioconversion has been investigated. The ability of selected substrates for induction of cellulase enzyme by A. oryzae ITCC 4857.01 and for the potentiality of the induced enzyme to saccharify the substrates were also assessed. The maximum degree of conversion of substrate (0.415%) and improved specific substrate consumption (0.99 g substrate/g dry biomass) was exhibited in sugarcane bagasse after alkali treatment at 96...
Tipo: Journal article
Palavras-chave: Aspergillus oryzae; Biomass; Cellulase; Lignocellulosic substrates; Pre-treatment; Saccharification.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500003

Efficient identification of tetR-expressing cell lines for tetracycline-regulated gene expression
Provedor de dados: Electronic Journal of Biotechnology
Autores: Song,Ping; Wang,Hwa-Chain Robert.
The technology of tetracycline-inducible gene expression has been successfully used in experimental biology to identify the function and downstream signaling pathways of an interested gene. It has been significantly improved to meet the criteria with specificity to exogenous non-toxic inducers, independent regulation from cellular pathways, and dose-dependent inducibility and reversibility. However, to establish tetracycline-inducible gene expression in mammalian cells is still a time-and effort-consuming process. With a tetracycline-inducible gene expression system T-REx, we have developed a practical protocol to use the oncogenic H-ras gene as a dominant reporter gene to increase efficiency in attaining desired cell lines in which ectopic expression of a...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200013

Use of Candida rugosa lipase immobilized on sepabeads for the amyl caprylate synthesis: Batch and fluidized bed reactor study
Provedor de dados: Electronic Journal of Biotechnology
Autores: Saponji,Svetlana; Kneevi-Jugovi,Zorica D; Bezbradica,Dejan I; Zuza,Milena G; Saied,Omar Ali; Boskovi-Vragolovi,Nevenka; Mijin,Dusan Z.
Lipase from Candida rugosa was covalently immobilized on Sepabeads EC-EP for application for amyl caprylate synthesis in an organic solvent system. Several solvents were tested in terms of biocatalyst stability and the best result was obtained with isooctane. The lipase-catalyzed esterification in the selected system was performed in batch and fluidized bed reactor systems. The influence of several important reaction parameters including temperature, initial water content, enzyme loading, acid/alcohol molar ratio, and time of addition of molecular sieves is carefully analyzed by means of an experimental design. Almost complete conversion (&gt; 99%) of the substrate to ester could be performed in a batch reactor system, using lipase loading as low as 37 mg...
Tipo: Journal article
Palavras-chave: Bioreactors; Covalent immobilization; Ester; Non-aqueous system; Optimization technique.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600012

Gene expression of a putative glutathione S-transferase is responsive to abiotic stress in embryogenic cell cultures of Cyclamen persicum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hoenemann,Claudia; Ambold,Juliane; Hohe,Annette.
Background: Cyclamen persicum is an economically important ornamental crop that is propagated exclusively through seeds as vegetative propagation using cuttings is not possible. Therefore a micropropagation method through somatic embryogenesis is of high interest; however the method suffers from low reliability concerning quality and quantity of the produced plantlets. A crucial step of the protocol is the removal of plant growth regulators (PGRs) that triggers embryo development. In order to get a better insight in this crucial step of the propagation process, a gene expression analysis has been set up using five different genes of glutathione S-transferases (GST) as these are known to be auxin responsive as well as stress reactive. Results: One out of...
Tipo: Journal article
Palavras-chave: Auxin; Callus; Micropropagation; Semisolid medium; Suspension culture.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000100006

Thiosulphate oxidation by Thiobacillus thioparus and Halothiobacillus neapolitanus strains isolated from the petrochemical industry
Provedor de dados: Electronic Journal of Biotechnology
Autores: Valdebenito-Rolack,Emky H; Araya,Tamara C; Abarzua,Leslie E; Ruiz-Tagle,Nathaly M; Sossa,Katherine E; Aroca,Germán E; Urrutia,Homero E.
Sulphur Oxidizing Bacteria (SOB) is a group of microorganisms widely used for the biofiltration of Total Reduced Sulphur compounds (TRS). TRS are bad smelling compounds with neurotoxic activity which are produced by different industries (cellulose, petrochemical). Thiobacillus thioparus has the capability to oxidize organic TRS, and strains of this bacterium are commonly used for TRS biofiltration technology. In this study, two thiosulphate oxidizing strains were isolated from a petrochemical plant (ENAP BioBio, Chile). They were subjected to molecular analysis by real time PCR using specific primers for T. thioparus. rDNA16S were sequenced using universal primers and their corresponding thiosulphate activities were compared with the reference strain T....
Tipo: Journal article
Palavras-chave: Biofiltration; Dimethyldisulphide; Dimethylsulphide; Thiobacillus; Thiosulphate.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100007

The release of light metals from a brown seaweed (Sargassum sp.) during zinc biosorption in a continuous system
Provedor de dados: Electronic Journal of Biotechnology
Autores: da Costa,Antonio Carlos Augusto; Mora Tavares,Ana Paula; Pessôa de França,Francisca.
The biosorption of zinc and calcium was investigated with a biomass of Sargassum sp., a brown seaweed, in a continuous system consisting of three serial tubular fixed-bed laboratory reactors. Results indicated that zinc was efficiently recovered by the biomass. After treatment of 9.0 liters of a mixed solution containing 130.0 mg/l zinc and 260.0 mg/l calcium, the first column of the system saturated with zinc; the remaining columns did not saturate with zinc as a result of the pre treatment performed by the first reactor. Calcium was also efficiently biosorbed by the biomass, saturating the system much faster than zinc. X-ray fluorescence spectrum indicated the presence of various elements in the structure of the Sargassum sp. biomass, especially alkaline...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300007

Solid-state fermentation of Bacillus thuringiensis tolworthi to control fall armyworm in maize
Provedor de dados: Electronic Journal of Biotechnology
Autores: Fontana Capalbo,Deise Maria; Valicente,Fernando Hercule; Oliveira Moraes,Iracema de; Pelizer,Lúcia Helena.
The well-known entomopathogenic bacterium Bacillus thuringiensis (Bt) produces a spore-crystal complex which is responsible for its biocide characteristic, and the bacterium can be obtained by fermentation, either in liquid or semi-solid substrates. This paper presents a successful way to achieve solid-state fermentation of active Bt var. tolworthi (Btt) against Spodoptera frugiperda (fall armyworm) in corn. More than 10(9) CFU/g were obtained using humidified rice as substrate maintained in polypropylene bags. This active complex (substrate plus spore-crystal of Bt) was prepared in order to obtain 2 x 10(6) spores/mL; the final suspension then sprayed via tractor on corn fields. On the treated plants, mortality of neonate larvae was 100% within two days...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200009

Perspectives on the application of biotechnology to assist the genetic enhancement of plantain and banana (Musa spp.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Crouch,Jonathan H.; Vuylsteke,Dirk; Ortiz,Rodomiro.
Bananas and plantains (Musa spp.) are the most important tropical fruit crops. They form an integral component of the farming systems in the humid agroecological zones of the tropics. A broad array of applied cell and molecular techniques are increasingly being used worldwide to facilitate and enhance the handling and improvement of plantain and banana germplasm. Tissue culture is used for germplasm exchange, conservation and rapid multiplication, while in vitro seed germination (based on embryo culture or rescue) plays a critical role in generating hybrid plants. DNA marker systems have been developed in Musa to assist germplasm management, selection within the breeding pool or gene introgression from wild species, and for disease diagnosis. Likewise,...
Tipo: Journal article
Palavras-chave: Banana; Improvement; Micropropagation; DNA; Markers; Plantain.
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000100002

Optimization of phenoxazinone synthase production by response surface methodology and its application in Congo red decolourization
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jia,Honghua; Gao,Zhen; Ma,Yingying; Zhong,Chao; Xie,Yingchun; Zhou,Hua; Wei,Ping.
Background: Enzymatic decolourization has been recently proposed as a promising and eco-friendly method for treatment of synthetic dye-contaminated wastewaters. However, the processes require large quantities of enzymes, attracting significant attention in developing efficient methods for mass production of multifunctional enzymes. Several methods such as response surface methodology (RSM) and orthogonal experiment have been applied to optimize the parameters in bioprocesses for enzyme production. Results: In the present study, a laccase-like enzyme, phenoxazinone synthase (PHS) originated from Streptomyces antibioticus was recombinantly expressed in Escherichia coli BL21 (DE3). The production of PHS in E. coli BL21 was optimized by response surface...
Tipo: Journal article
Palavras-chave: Congo red; Decolourization; Laccase; Phenoxazinone synthase; Response surface methodology.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500002

Study on the relationship between intracellular metabolites and astaxanthin accumulation during Phaffia rhodozyma fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Xiao,Anfeng; Jiang,Xinglong; Ni,Hui; Yang,Qiuming; Cai,Huinong.
Background To study the relationship between intracellular anabolism and astaxanthin production, the influence of intracellular protein and fatty acids on astaxanthin production by four mutant Phaffia rhodozyma strains and their variations was investigated in this research. Results First, the content of astaxanthin in cells showed a reverse fluctuation in contrast to that of protein during the whole fermentation process. Moreover, compared with the three other strains, the astaxanthin-overproducing mutant strain of the yeast P. rhodozyma, called JMU-MVP14, had the highest specific productivity of astaxanthin as 6.8 mg/g, whereas its intracellular protein and fatty acid contents were the lowest. In addition, as a kind of sugar metabolic product, ethanol was...
Tipo: Journal article
Palavras-chave: Astaxanthin; Ethanol; Fatty acids; Phaffia rhodozyma; Protein.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300002

Anticancer and apoptosis-inducing activities of microbial metabolites
Provedor de dados: Electronic Journal of Biotechnology
Autores: Phonnok,Sirinet; Uthaisang-Tanechpongtamb,Wanlaya; Wongsatayanon,Benjamas Thanomsub.
The problems of systemic toxicity and drug resistance in cancer chemotherapy urge the continuing discovery of new anticancer agents. We explored the specific anticancer activity from microbial metabolites to find new lead compound. 394 microbial extracts were evaluated on anti-proliferative activity against 4 cancer cell lines using MTT assay. Of these, 20 samples showed varying degree of cytotoxicity but specifically to the cancer cell lines since the growth of normal cells was not significantly inhibited by 1 mg/ml of each cell extracts. The 4 most potent extracts exhibited strongest growth inhibition to each cancer cell type were selected for further studied. Cell morphological changes such as cell shrinkage, lose of surface contact and blebbing were...
Tipo: Journal article
Palavras-chave: Anticancer; Apoptosis; Bioactive compound; Caspase; Microbial product.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500001

Superparamagnetic Poly (3-hydroxybutyrate-co-3 hydroxyvalerate) (PHBV) nanoparticles for biomedical applications
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vilos,Cristian; Gutiérrez,Marlen; Escobar,Roberto A; Morales,Francisco; Denardin,Juliano C; Velasquez,Luis; Altbir,Dora.
Background: The progress in material science and the recent advances in biodegradable/biocompatible polymers and magnetic iron oxide nanoparticles have led to develop innovative diagnostic and therapeutic strategies for diseases based on multifunctional nanoparticles, which include contrast medium for magnetic resonance imaging, agent for hyperthermia and nanocarriers for targeted drug delivery. The aim of this work is to synthesize and characterize superparamagnetic iron oxide (magnetite), and to encapsulate them into poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanoparticles for biomedical applications. Results: The magnetite nanoparticles were confirmed by X-ray diffraction and exhibited a size of 22.3 ± 8.8 nm measured by transmission electron...
Tipo: Journal article
Palavras-chave: Hyperthermia; Magnetic resonance image; Magnetite; PHBV; Polymeric nanoparticles.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500008

Monitoring the threat of unintentional transgene flow into maize gene banks and breeding materials
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mezzalama,Monica; Crouch,Jonathan H; Ortiz,Rodomiro.
The use of transgenic crops is steadily increasing around the world, led by soybean (based on total area) and maize (in terms of total number of countries). Transgenic maize is grown in at least 17 countries across four continents: Africa, America, Asia and Europe. The comprehensive global spread of transgenic maize has significant implications for organizations involved in germplasm conservation and genetic enhancement; particularly as some countries require a GMO-free declaration when receiving shipments of maize germplasm. This article describes the protocol used by the International Maize and Wheat Improvement Center (CIMMYT) for monitoring unintentional transgene flow in maize genebank and breeding plots. The protocol is based on polymerase chain...
Tipo: Journal article
Palavras-chave: Biosafety; Genetic integrity; Germplasm enhancement; GM-maize.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000200006

Semiquantitative analysis of genetically modified maize and soybean in food
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cazzola,María Laura; Petruccelli,Silvana.
The aim of this study was to analyze quantitatively the presence of genetically modified organism in food with different composition and degree of processing. Total DNA was extracted by Dellaporta's method and GMO analysis was performed using two consecutives PCR reactions with specie specific primers (IVR and LE), screening primers (35S) and transgen specific primers (CRY and EPSPS). The quantification within the sensitivity establish by the EU was possible only in some foods (ice-cream, flours, soybean isolates and concentrates, starch). Samples with high lipid content or subjected to intense thermal treatments (such as some snacks, mayonnaise, creamy soup) could not be amplified mainly due to the presence of PCR inhibitors. Therefore the method was...
Tipo: Journal article
Palavras-chave: Bt maize; Genetically modified organisms; Semi-quantitative PCR; RR-soybean; Transgenic food.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300028

In vitro plant regeneration system for common bean (Phaseolus vulgaris): effect of N6-benzylaminopurine and adenine sulphate
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gatica Arias,Andrés M; Muñoz Valverde,Jenny; Ramírez Fonseca,Pilar; Valdez Melara,Marta.
A method for regeneration of the commercially important common bean (Phaseolus vulgaris ) using N6-benzylaminopurine(BAP) and adenine sulphate (AS) was established. Embryogenic axes of the Costa Rican common bean cultivars Bribrí, Brunca, Guaymí, Huetar and Telire were cultured on Murashige and Skoog medium supplemented with 100 mgl-1 myo-inositol, 1 mgl-1 thiamine, 30 gl-1 sucrose, BAP (0, 5 and 10 mgl-1), AS (0, 20 and 40 mgl-1) and 8 gl-1 agar. Regardless of the concentration of BAP and AS in the induction medium, the number of shoots and leaves differed significantly among the common bean cultivars evaluated. The higher average of shoots was obtained for Brunca &gt; Telire &gt; Bribrí &gt; Guaymí &gt; Huetar. Moreover, independently of the cultivar,...
Tipo: Journal article
Palavras-chave: Common bean; In vitro culture; Morphogenesis; Phaseolus vulgaris L.; Plant growth regulators.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100006

Corrigendum to The effect of high concentrations of glycerol on the growth, metabolism and adaptation capacity of Clostridium butyricum DSP1
Provedor de dados: Electronic Journal of Biotechnology
Autores: Szymanowska-Powalowska,Daria.
Tipo: Journal article
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500011

Uniparental genetic systems: a male and a female perspective in the domestic cattle origin and evolution
Provedor de dados: Electronic Journal of Biotechnology
Autores: Di Lorenzo,Piera; Lancioni,Hovirag; Ceccobelli,Simone; Curcio,Ludovica; Panella,Francesco; Lasagna,Emiliano.
Over the last 20 years, the two uniparentally inherited marker systems, namely mitochondrial DNA and Y chromosome have been widely employed to solve questions about origin and prehistorical range expansions, demographic processes, both in humans and domestic animals. The mtDNA and the Y chromosome, with their unique patterns of inheritance, continue to be extremely important source of information. These markers played significant roles in farm animals in the evaluation of the genetic variation within- and among-breed strains and lines and have widely applied in the fields of linkage mapping, paternity tests, prediction of breeding values in genome-assisted selection, analysis of genetic diversity within breeds detection of population admixture, assessment...
Tipo: Journal article
Palavras-chave: Animal breeding; Bovine domestication; Cattle genetic diversity; Genetic resources; Genome-assisted selection; Inherited marker systems.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500010

Genomic variability in Vitis vinifera L. "Sangiovese" assessed by microsatellite and non-radioactive AFLP test
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vignani,Rita; Scali,Monica; Masi,Elisa; Cresti,Mauro.
Microsatellite polymorphism analysis on 25 different "Sangiovese" accessions was carried out at eight microsatellite loci (VVS2, VVS4, VVS29, VVMD3, VVMD6, VVMD7, VVMD17 and VVMD21). In order to evaluate variability within the "Sangiovese" variety and to confirm variety identification, genotype analysis, allele distribution and pedigree information were processed with a DNA-automated sequencer running AlleleLinks software. DNA typing revealed three cases of genetic dissimilarity compared to registered "Sangiovese" clones and the divergent accessions thought to be different clones of the same variety. The divergent accessions were different from "Sangiovese" at four microsatellite loci (VVS2, VVS4, VVMD7 and VVMD21). An innovative non-radioactive...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100007

Biodeterioration patterns found in dammar resin used as art material
Provedor de dados: Electronic Journal of Biotechnology
Autores: Romero-Noguera,Julio; Martín-Sánchez,Inés; López-Miras,María del Mar; Ramos-López,José Miguel; Bolívar-Galiano,Fernando.
Since the middle of the XIX century, when dammar became popular in Occident, this natural resin is one of the most used in art painting techniques as final protective coating (varnish) as well as a component of pictorial media. The present work is the first approach to the study of the microbiological biodeterioration of this artistic material, which can seriously affect the appearance and integrity of works of art when bad conservation conditions -especially high humidity levels- take place. 12 microorganisms, fungi and bacteria, came from collection and from oil paintings affected by biodeterioration patterns, were inoculated on test specimens prepared with varnish dammar. These were incubated and analyzed by GC-MS to determine both the microbiological...
Tipo: Journal article
Palavras-chave: Bacteria; Biodeterioration; Dammar; Fungi; GC-MS.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300006

Biological treatment of contaminated air with toluene in an airlift reactor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vergara-Fernández,Alberto O; Quiroz,Erich F; Aroca,Germán E; Alarcón Pulido,Nelson A.
In this work the variation in the toluene elimination capacity of an airlift bioreactor as a function of the toluene inlet load, using compost as the support material for the microorganisms was studied. In order to evaluate the flexibility of the reactor under changing toluene load, the toluene biodegradation was measured for flows from 2.4 x 10-2 to 0.132 m³ h-1, and a concentration range from 1.4 to 0.8 g m-3. Results show a 100% removal efficiency (RE) for minor flows, however, for a flow increase of 450% the RE decreased 40%, reflecting the equipments weak flexibility in varying flows. Meanwhile the maximum elimination capacity obtained was 230 g m-3 h-1, for toluene loads of 550 g m-3 h-1, corresponding to a flow of 0.132 m³ h-1. It was found that a...
Tipo: Journal article
Palavras-chave: Airlift bioreactors; Biofiltration; Bioscrubbers; Toluene.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400003

Development and application of qRT-PCR for sugar beet gene expression analysis in response to in vitro induced water deficit
Provedor de dados: Electronic Journal of Biotechnology
Autores: Taski-Ajdukovic,Ksenija; Nagl,Nevena; Kovacev,Lazar; Curcic,Zivko; Danojevic,Dario.
Sugar beet is a significant industrial crop, often grown in the areas where summer drought can severely limit root yield and sugar content. In order to improve development of sugar beet cultivars with increased drought tolerance it is necessary to understand plant response to water stress at the genomic level. Since recent research efforts have focused on the molecular response of the plant in order to identify water deficit inducible genes, the aim of this investigation was to develop qRT-PCR methodology for the quantification of gene expression in sugar beet under conditions of water deficiency in vitro. Sugar beet genotypes, selected for different response to water deficit, were grown and multiplied in vitro. Axilary shoots were placed on...
Tipo: Journal article
Palavras-chave: Beta vulgaris; Drought; In vitro; Real-time PCR.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600010

Callus culture for biomass production of milk thistle as a potential source of milk clotting peptidases
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cimino,Cecilia; Vairo Cavalli,Sandra; Spina,Francisco; Natalucci,Claudia; Priolo,Nora.
The objective of this work was the optimization of the conditions of in vitro culture for callus production of Silybum marianum (L.) Gaertn. (Asteraceae). Sections of cotyledons, previously disinfected by washing successively with ethanol 70&amp;ordm;, NaClO (10% w/v) and Tween 20 (0.05% v/v) and rinsing with sterile distilled water, were used as explants. For its initial culture, B5 medium supplemented with BA and 2,4-D solidified with phytagel was used, and a 63% survival was achieved. To obtain callus, two solid media were assayed (S1 and S2) using B5 medium supplemented with growth regulators (BA and 2,4-D or NAA and BA, respectively). The calli were grown at 25&amp;ordm;C during 45 days in darkness. Growth kinetics was studied using S1 medium...
Tipo: Journal article
Palavras-chave: Asteraceae; Callus; Rhizogenesis; Silybum marianum.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300012

Advances in the development of a noninvasive embryo model for the evaluation of the quality of cloned embryos subjected to different treatments
Provedor de dados: Electronic Journal of Biotechnology
Autores: Felmer,Ricardo; Arias,María Elena.
Total number of cells in cloned embryos is generally lower than that of in vivo derived embryos and in bovines cell allocation at the blastocyst stage, has been observed to be affected in a large proportion of cloned embryos. The current embryo staining procedures are toxic for mammalian cells and thus can not be used to determine the developmental potential of a stained embryo. Therefore, in the present study we sought to assess the feasibility to develop a noninvasive embryo model that would be suitable for the evaluation of cloned embryos subjected to different nuclear transfer and embryo culture procedures. For doing this, we stably transfected a bovine embryonic fibroblast cell line and generated a number of clones that constitutively expressed a red...
Tipo: Journal article
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000500002

Catalytical properties of N-glycosylated Gluconacetobacter diazotrophicus levansucrase produced in yeast
Provedor de dados: Electronic Journal of Biotechnology
Autores: Trujillo Toledo,Luis Enrique; Gómez Riera,Raúl; Banguela Castillo,Alexander; Soto Romero,Melvis; Arrieta Sosa,Juan Gabriel; Hernández García,Lázaro.
The influence of N-glycosylation on the kinetic and catalytical properties of a bacterial fructosyltransferase (LsdA) produced in Pichia pastoris was studied. The glycosylated enzyme behaved similarly to non-glycosylated LsdA when substrate specificity, fructo-oligosaccharide (FOS) production, sucrose hydrolysis or levan formation reactions were carried out under different experimental conditions. The kinetic parameters for native or yeast-expressed LsdA determined at 60ºC, condition for the highest hydrolytic activity, followed a conventional Michaelis-Menten kinetics. Synthase activity of this levansucrase increased in water-restricted environments by addition of salt or organic solvent to the reaction mixtures
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200005

Transgenic trees and forestry biosafety
Provedor de dados: Electronic Journal of Biotechnology
Autores: Valenzuela,Sofía; Balocchi,Claudio; Rodríguez,Jaime.
The benefits from the development of transgenic trees are expected from the improvement of traits as growth and form, wood quality, industrial processes, disease and insect resistance, herbicide tolerance, ecological restoration, rooting ability, etc. One of the first reported field trials with genetically modified forest trees was established in Belgium in 1988 and the characteristic evaluated was herbicide tolerance in poplars. Since then, there have been more than 200 reported trials, involving at least 15 forest species. The majority of the field trials have been carried out in the USA (64%). More than 50% of the field trials are done with Populus species and the main target traits are herbicide tolerance (31%), followed by marker genes (23%) and...
Tipo: Journal article
Palavras-chave: Biosafety; Forestry biotechnology; GMOs; GM trees.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300031

Plant biotechnology and food security in Latin America and the Caribbean
Provedor de dados: Electronic Journal of Biotechnology
Autores: de la Riva,Gustavo A.
Agriculture is expected to feed an increasing population, forecasted to reach 8 billion by 2020, out of whom 6.7 billion will be in developing countries where the carrying capacity of agricultural lands will soon be reached. In Latin American and the Caribbean (LAC) countries, in spite of the abundance of natural resources and continued investments in development, poverty and food insecurity affect more than 55 percent of the rural population. Fifteen years ago, plant biotechnology comprised only a few applications of tissue culture, recombinant DNA technology and monoclonal antibodies. Today, genetic transformation, and marker-aided selection and breeding are just a few of the examples of the applications in crop improvement with profound implications for...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000100001

The True Meaning of Technology Transfer
Provedor de dados: Electronic Journal of Biotechnology
Autores: Glew,Robert H.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100005

QTL mapping for physiology, yield and plant architecture traits in cotton (Gossypium hirsutum L.) grown under well-watered versus water-stress conditions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Saeed,Muhammad; Guo,Wangzhen; Ullah,Ihsan; Tabbasam,Nabila; Zafar,Yusuf; Mehboob-ur-Rahman,; Zhang,Tianzhen.
Increasing scarcity of irrigation water is a major threat to sustainable production of cotton (Gossypium hirsutum L.). Identifying genomic regions contributing to abiotic stress tolerance will help develop cotton cultivars suitable for water-limited regions through molecular marker-assisted breeding. A molecular mapping F2 population was derived from an intraspecific cross of the drought sensitive G. hirsutum cv. FH-901 and drought tolerant G. hirsutum cv. RH-510. Field data were recorded on physiological traits (osmotic potential and osmotic adjustment); yield and its component traits (seedcotton yield, number of bolls/plant and boll weight); and plant architecture traits (plant height and number of nodes per plant) for F2, F2:3 and F2:4 generations under...
Tipo: Journal article
Palavras-chave: Composite interval mapping; Cotton; Drought tolerance.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300003

An international political economic view of the biotechnology industry
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pownall,Ian Edward.
This paper uses a model developed from the international political economy (IPE) school, to address the structure of the biotechnology industry. In particular, by focusing upon four primary structural elements of the industry, knowledge, production, finance and security with key secondary considerations of biosafety, public opinion and choice of intellectual property regime, the development of biotechnology companies from developed countries fits within a triad dominated industry with specific interests towards firms from developing countries. The activities of a sample of US National Association of Securities Dealers Stock Market (NASDAQ) quoted biotechnology firms are investigated to support the model which concludes by the observation of the need to...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000200004

An RT-PCR artifact in the characterization of bacterial operons
Provedor de dados: Electronic Journal of Biotechnology
Autores: Guacucano,Maritza; Levican,Gloria; S. Holmes,David; Jedlicki,Eugenia.
During the course of experiments involving RT-PCR to investigate the co-transcription of the pet and res operons of the bacterium Acidithiobacillus ferrooxidans we observed that the mRNA of certain gene pairs can be amplified by RT-PCR in the absence of added RT-primer. We provide experimental evidence that eliminates, as explanations for the observed results, the possible global contamination of the RNA preparation by genomic DNA or by contaminating single stranded DNA or RNA fragments. We suggest that the results can be explained by self-priming of the RNA perhaps as a result of secondary structure configurations that provide a suitable 3’-terminus to prime the reverse transcriptase. This type of artifact can be recognized by carrying out a control in...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000300005

Stable expression and characterization of a fungal pectinase and bacterial peroxidase genes in tobacco chloroplast
Provedor de dados: Electronic Journal of Biotechnology
Autores: Espinoza-Sánchez,Edward Alexander; Álvarez-Hernández,Marianela Hazel; Torres-Castillo,Jorge Ariel; Rascón-Cruz,Quintín; Gutiérrez-Díez,Adriana; Zavala-García,Francisco; Sinagawa-García,Sugey Ramona.
Background The high capacity of chloroplast genome response to integrate and express transgenes at high levels makes this technology a good option to produce proteins of interest. This report presents the stable expression of Pectin lyase (PelA gene) and the first stable expression of manganese peroxidase (MnP-2 gene) from the chloroplast genome. Results pES4 and pES5 vectors were derived from pPV111A plasmid and contain the PelA and MnP-2 synthetic genes, respectively. Both genes are flanked by a synthetic rrn16S promoter and the 3'UTR from rbcL gene. Efficient gene integration into both inverted repeats of the intergenic region between rrn16S and 3'rps'12 was confirmed by Southern blot. Stable processing and expression of the RNA were confirmed by...
Tipo: Journal article
Palavras-chave: Cell wall; Chloroplast genetic transformation; Hydrolytic enzyme; Nicotiana tabacum.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300004

Analysis of batch and repeated fedbatch productions of Candida utilis cell mass using mathematical modeling method
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lin,Yutian; Liu,Guoli; Lin,Huibin; Gao,Ling; Lin,Jianqiang.
Background: Candida utilis is widely used in bioindustry, and its cell mass needs to be produced in a cost effective way. Process optimization based on the experimental results is the major way to reduce the production cost. However, this process is expensive, time consuming and labor intensive. Mathematical modeling is a useful tool for process analysis and optimization. Furthermore, sufficient information can be obtained with fewer experiments by using the mathematical modeling, and some results can be predicted even without doing experiments. Results: In the present study, we performed the mathematical modeling and simulation for the cell mass production of Candida utilis based on limited batch and repeated fedbatch experiments. The model parameters...
Tipo: Journal article
Palavras-chave: Candida utilis; Fermentation; Genetic algorithm; Mathematical model.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400002

Hydrothermal multivariable approach: Full-scale feasibility study
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pérez-Elvira,Sara I; Fernández-Polanco,Fernando; Fernández-Polanco,María; Rodríguez,Pilar; Rouge,Philippe.
A process configuration combining thermal hydrolysis (TH) and anaerobic digestion (AD) of sludge has been studied with the objective of analysing the feasibility of the technology for full scale installations. The study has been performed through pilot scale experiments and energy integration considerations, and a scheme of the most profitable option is presented: thermal hydrolysis unit fed with 7% total solids (TS) secondary sludge, anaerobic digestion of the hydrolysed sludge together with fresh primary sludge, and a cogeneration unit to produce green electricity and provide hot steam for the thermal hydrolysis process. From a technical and practical point of view, the process scheme proposed is considered to be feasible. Based on the results of the...
Tipo: Journal article
Palavras-chave: Anaerobic digestion; Biogas; Sludge; Sludge properties; Thermal hydrolysis.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400007

Molecular authentication of the traditional Chinese medicinal plant Angelica sinensis based on internal transcribed spacer of nrDNA
Provedor de dados: Electronic Journal of Biotechnology
Autores: Feng,Tu; Liu,Shuang; He,Xing-jin.
Traditionally, the authentication of the traditional Chinese medicines (TCM), Angelica sinensis, is based on slightly different morphological characters and complex compounds. Usually, those methods are simultaneously affected by several factors, leading to subtle and ambiguous results. In this study, the internal transcribed spacer (ITS) regions of A. sinensis and seven other Angelica species used as adulterants were sequenced. A pair of specific primers was designed from the polymorphic ITS regions to distinguish A. sinensis from the adulterants and regional substitutes. These ITS-derived primers amplified approximately 520 bp specific fragments from the adulterants, whereas no products was amplified with the DNA of A. sinensis. We tested eight...
Tipo: Journal article
Palavras-chave: Angelica sinensis; Internal transcribed spacer; Molecular authentication; Specific primers; Traditional Chinese medicine.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100009

Levans production by Gluconacetobacter diazotrophicus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Molinari,María Laura; Boiardi,José Luis.
Background: Growth of Gluconacetobacter diazotrophicus with glucose as carbon an energy source has been extensively studied. However, there are no reports in the literature describing growth of G. diazotrophicus in cultures containing sucrose as carbon source. The first step in sucrose pathway and production of levans was investigated. Biomass, levans, gluconic acid and keto gluconic acids production and levansucrase activity were determined in cultures with different sucrose concentration and nitrogen sources. Results: The biomass production was maximal in cultures containing 100 g x L-1 sucrose and inorganic nitrogen. Gluconic acid production was observed under all conditions tested, at levels up to 9 g x L-1 in cultures with sucrose excess and...
Tipo: Journal article
Palavras-chave: Gluconic acid; Keto gluconic acids; Levans; Levansucrase; Sucrose metabolism.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300007

Sugarcane bagasse as feedstock for cellulase production by Trichoderma harzianum in optimized culture medium
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rocha,Vanessa Alves Lima; Maeda,Roberto Nobuyuki; Santa Anna,Lidia Maria Melo; Pereira,Nei.
This work aimed at the production of cellulases from pretreated sugarcane bagasse by the filamentous fungus Trichoderma harzianum IOC 3844 and their application in the hydrolysis of this same substrate, for a future use in second-generation ethanol production. The production of cellulases was optimized, which resulted in high enzymatic activities after 42 hrs of process in an instrumented bioreactor (CMCase 27,017 U x L-1; FPase 1,225 U x L-1; and &amp;#946;-glucosidase 609 U x L-1). The enzymatic extract was concentrated by using a hollow fiber membrane filtration system. The concentrated extract was applied in the hydrolysis of pretreated sugarcane bagasse, after 28 hrs of enzymatic reaction, displaying a similar catalytic performance of that attained...
Tipo: Journal article
Palavras-chave: Electrophoresis; Enzymatic hydrolysis; Second generation ethanol; Trichoderma harzianum.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500012

Callus induction and plant regeneration of Ulex europaeus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ramírez,Ingrid; Dorta,Fernando; Cuadros-Inostroza,Álvaro; Peña-Cortés,Hugo.
A callus induction and plant regeneration protocol was developed from leaf and thorn explants for the plant Ulex europaeus. Explants were incubated on 2% sucrose half-strength Murashige and Skoog Medium (MS) with various combinations of plant growth regulators and antioxidants. The best frequency of callus and shoot formation was obtained with 2,4-dichlorophenoxyacetic acid (2,4-D) 1 mg/l x kinetin (Kin) 0.2 mg/l (DK Medium; callus induction) and zeatin (Z) 1 mg/l (DK medium; shoot induction). Both media were supplemented with ascorbic acid 200 mg/l to prevent browning and death of the explants. The regenerated shoots transferred to rooting medium (half-strength MS Medium, 2% sucrose) showed rapid growth and development of roots (100%). Rooted plantlets...
Tipo: Journal article
Palavras-chave: Antioxidants; Callus induction; Fabaceae; Gorse; Plant regeneration; Ulex europaeus.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000400007

Effect of glutaraldehyde biocide on laboratory-scale rotating biological contactors and biocide efficacy
Provedor de dados: Electronic Journal of Biotechnology
Autores: Laopaiboon,Lakkana; Phukoetphim,Niphaphat; Laopaiboon,Pattana.
The effect of glutaraldehyde, a commercial biocide widely used in paper and pulp industry, on the performance of laboratory-scale rotating biological contactors (RBCs) as well as biocide efficacy was studied. Biofilms were established on the RBCs and then exposed to 0 - 180 ppm glutaraldehyde at a dilution rate of 1.60 h-1. The results showed that the biofilms became acclimated to glutaraldehyde and eventually could degrade it. Acclimation to the biocide took longer at the higher biocide concentrations. The degree of biocide degradation and chemical oxygen demand (COD) removal depended on acclimation period, the presence of other organic matters and the amount of mineral salts available. Glutaraldehyde at up to 80 ppm had no effect on treatment efficiency...
Tipo: Journal article
Palavras-chave: Acclimation; Aldehyde biocide; Biofilm; RBC; Wastewater treatment.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400003

Genomic sequence derived simple sequence repeats markers A case study with Medicago spp.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mahalakshmi,Viswanathan; Aparna,P.; Ramadevi,S.; Ortiz,Rodomiro.
Simple sequence repeats (SSR) or micro-satellites are becoming standard DNA markers for plant genome analysis and are being used as markers in marker assisted breeding. De novo generation of micro-satellite markers through laboratory-based screening of SSR-enriched genomic libraries is highly time consuming and expensive. An alternative is to screen the public databases of related model species where abundant sequence data is already available. All the genomic sequences of Medicago from the public domain database were searched and analysed of di, tri, and tetra nucleotide repeats. Of the total of about 156,000 sequences which were searched, 7325 sequences were found to contain repeat motif and may yield SSR which will yield product sizes of around 200 bp....
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300007

Inhibition of attachment of some fouling diatoms and settlement of Ulva lactuca zoospores by film-forming bacterium and their extracellular products isolated from biofouled substrata in Northern Chile
Provedor de dados: Electronic Journal of Biotechnology
Autores: Silva-Aciares,Fernando; Riquelme,Carlos.
The biofouling of surfaces submerged in the marine environment includes primary colonization of the substrate by microorganisms including bacteria, microalgae, and microscopic reproductive propagules of macroorganisms such as algal zoospores. The present study reports the evaluation of the inhibitory potential of biofilms and extracellular products (EP) of the indigenous bacterium Alteromonas sp strain Ni1-LEM on the settlement of marine biofouling such as: (i) eight marine benthic diatoms and (ii) zoospores of the alga Ulva lactuca, as well as the germination of these zoospores and was compared with reference strains with proven antifouling properties, Halomonas marina (ATCC 25374) and Pseudoalteromonas tunicata. Highest antifouling activity was found for...
Tipo: Journal article
Palavras-chave: Alteromonas sp; Antifouling bacteria; Antifouling compounds; Diatoms; Marine microfouling; Ulva zoospores.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100006

Expression of RNA polymerase IV and V in Oryza sativa
Provedor de dados: Electronic Journal of Biotechnology
Autores: Moo,Leydi de Rocio Canche; González,Angela Kú; Rodríguez-Zapata,Luis Carlos; Suarez,Victor; Castaño,Enrique.
RNA polymerase IV and V are principal players in the RdDM pathway, where their current study has shown interaction of several factors that control DNA silencing of intergenic regions and siRNA production. DNA silencing is an important process during cell differentiation, nuclear structure and viral control. However, RNA pol IV and V are yet to be study in model monocot systems like Oryza sativa that can provide further information on genetic silence mechanism in plats. We show the expression pattern of these polymerases in tissues extracts of Oryza sativa. Detectable amounts of these polymerases are found in specific adult plant tissues and particularly expressed during somatic embryogenesis but not during early stages of normal embryo development. The use...
Tipo: Journal article
Palavras-chave: Oryza sativa; RNA pol IV; RNA pol V; Somatic embryogenesis; Zygotic embryogenesis.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000200009

Boty-II, a novel LTR retrotransposon in Botrytis cinerea B05.10 revealed by genomic sequence
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhao,Ming; Zhou,Jin yan; Li,Zhi dong; Song,Wei wei; Tan,You jiu; Tan,Hong.
Botrytis cinerea is a necrotrophic pathogen causing pre- and post-harvest diseases in at least 235 plant species. It manifests extraordinary genotype and phenotype variation. One of the causes of this variation is transposable elements. Two transposable elements have been discovered in this fungus, the retrotransposon (Boty), and the transposon (Flipper). In this work, two complete (Boty-II-76 and Boty-II-103) and two partial (Boty-II-95 and Boty-II-141) long terminal repeat (LTR) retrotransposons were identified by an in silico genomic sequence analysis. Boty-II-76 and Boty-II-103 contain 6439 bp nucleotides with a pair of LTRs at both ends, and an internal deduced pol gene encoding a polyprotein with reverse transcriptase and DDE integrase domains. They...
Tipo: Journal article
Palavras-chave: Botrytis cinerea; LTR retrotransposons; Molecular marker; Plant pathogen; Population diversity; Transposable elements.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300002

Repetitive element palindromic PCR (rep-PCR) as a genetic tool to study interspecific diversity in Euphorbiaceae family
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rampadarath,Sillma; Puchooa,Daneshwar; Bal,Subhasisa.
Background The classification of diversity in germplasm collections is important for plant breeding. The repetitive element palindromic-polymerase chain reaction (rep-PCR) technique was used to investigate inter-specific diversity within 17 species from the Euphorbiaceae family using REP and BOX primers. Results The agglomerative cluster analysis was used to evaluate the scoring data. BOX and REP gave amplification with polymorphism of 98.84% and 100% respectively. REP marker demarcated between the subgenus peltatae. Both markers confirmed Jatropha tanjorensis as a natural hybrid between Jatropha gossypifolia and Jatropha curcas. Five random sequences from the rep-PCR gels were chosen, cloned and sequenced. The blast results demonstrated that the amplified...
Tipo: Journal article
Palavras-chave: Euphorbiaceae; Genetic diversity; Jatropha; Mitochondrial genome; Rep-PCR.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600005

Enzymatic hydrolysis and fermentation of ultradispersed wood particles after ultrasonic pretreatment
Provedor de dados: Electronic Journal of Biotechnology
Autores: Revin,Victor; Atykyan,Nelli; Zakharkin,Denis.
Background: A study of the correlation between the particle size of lignocellulosic substrates and ultrasound pretreatment on the efficiency of further enzymatic hydrolysis and fermentation to ethanol. Results: The maximum concentrations of glucose and, to a lesser extent, di- and trisaccharides were obtained in a series of experiments with 48-h enzymatic hydrolysis of pine raw materials ground at 380-100 rpm for 30 min. The highest glucose yield was observed at the end of the hydrolysis with a cellulase dosage of 10 mg of protein (204 ±21 units CMCase per g of sawdust). The greatest enzymatic hydrolysis efficiency was observed in a sample that combined two-stage grinding at 400 rpm with ultrasonic treatment for 5-10 min at a power of 10 W per kg of...
Tipo: Journal article
Palavras-chave: Bioethanol; Ligsnocelluloses; Yeast Saccharomyces cerevisiae.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000200003

Isolation and identification of a cellulolytic bacterium from the Tibetan pig's intestine and investigation of its cellulase production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yang,Weiping; Meng,Fanxu; Peng,Jiayin; Han,Peng; Fang,Fang; Ma,Li; Cao,Binyun.
Background The Tibetan pig is a pig breed with excellent grazing characteristics indigenous to the Qinghai-Tibet plateau in China. Under conditions of barn feeding, 90% of its diet consists of forage grass, which helps meet its nutritional needs. The present study aimed to isolate and identify a cellulolytic bacterium from the Tibetan pig's intestine and investigate cellulase production by this bacterium. The study purpose is to provide a basic theory for the research and development of herbivore characteristics and to identify a source of probiotics from the Tibetan pig. Results A cellulolytic bacterium was isolated from a Tibetan pig's intestine and identified based on morphological, physiological, and biochemical characteristics as well as 16S rRNA...
Tipo: Journal article
Palavras-chave: Carboxymethyl cellulose; Cellulolytic bacterium; Fermentation conditions; Screening and identification; Tibetan pig.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600002

Data mining and influential analysis of gene expression data for plant resistance gene identification in tomato (Solanum lycopersicum)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Torres-Avilés,Francisco; Romeo,José S; López-Kleine,Liliana.
Background Molecular mechanisms of plant-pathogen interactions have been studied thoroughly but much about them is still unknown. A better understanding of these mechanisms and the detection of new resistance genes can improve crop production and food supply. Extracting this knowledge from available genomic data is a challenging task. Results Here, we evaluate the usefulness of clustering, data-mining and regression to identify potential new resistance genes. Three types of analyses were conducted separately over two conditions, tomatoes inoculated with Phytophthora infestans and not inoculated tomatoes. Predictions for 10 new resistance genes obtained by all applied methods were selected as being the most reliable and are therefore reported as potential...
Tipo: Journal article
Palavras-chave: Classification; Data mining; Functional gene prediction; GEE models; Gene expression data; Plant immunity genes.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000200004

Optimization of culture conditions for exopolysaccharides production in Rhizobium sp. using the response surface method
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pereira Duta,Flávia; Pessôa de França,Francisca; de Almeida Lopes,Léa Maria.
The combined effects of the processing parameters for exopolysaccharides production by Rhizobium sp. was studied using the experimental design and response surface methodology. The experiments were carried out using a fermenter with 20 L capacity, as the reactor. All processing parameters were online monitored. The temperature [(30 &amp;plusmn; 1)&amp;ordm;C] and pH value (7.0 &amp;plusmn; 0.1) were kept constant throughout the experimental time. As statistical tools, a complete 2³ factorial planning with central point and response surface were used to study the interactions among three relevant variables of the fermentation process: calcium carbonate concentration, aeration and agitation. The processing parameters setup for reaching a maximum response for...
Tipo: Journal article
Palavras-chave: Exopolysaccharides; Experimental design; Response surface method; Rhizobium sp.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400007

Medicinal Plants: A Re-emerging Health Aid
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hoareau,Lucy; DaSilva,Edgar J.
Interest in medicinal plants as a re-emerging health aid has been fuelled by the rising costs of prescription drugs in the maintenance of personal health and well being, and the bioprospecting of new plant-derived drugs. Several issues as well as a range of interests and activities in a number of countries are dealt with. Based on current research and financial investments, medicinal plants will, seemingly, continue to play an important role as a health aid.
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000200002

Establishment of a pheasant (Phasianus colchicus) spermatogonial stem cell line for the production of interspecies germ line chimeras
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kim,Jeong Hyun; Sharma,Neelesh; Kim,Sung Woo; Sodhi,Simrinder Singh; Ghosh,Mrinmoy; Kim,Nam Eun; Mongre,Raj Kumar; Oh,Sung Jong; Jeong,Dong Kee.
Background Spermatogonial stem cells (SSCs) are important for the production of interspecies germ line chimeras. The interspecies germ cell transfer technique has been suggested as a way to conserve endangered birds. Our objective was to develop a technique for restoring endangered birds by developing interspecies germ line chimeras between pheasant (Phasianus colchicus) and chicken (Gallus gallus) with SSCs. Results SSCs were isolated from the surgically removed testis of a pheasant. Growth conditions for pheasant SSCs were established by co-culturing STO (SIM mouse embryo-derived thioguanine and ouabain resistant) cells and pheasant SSCs. The colony-forming cells divided and proliferated stably to yield an established SSC line. Pheasant SSCs showed...
Tipo: Journal article
Palavras-chave: Endangered birds; In vitro culture; Recipient chicken embryos; SSC transplantation.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000500004

Molecular modeling of manganese peroxidase from the lignin-degrading fungus Ceriporiopsis subvermispora and structural comparison with other peroxidases
Provedor de dados: Electronic Journal of Biotechnology
Autores: Canales,Mauricio; Lobos,Sergio; Vicuña,Rafael.
Ceriporiopsis subvermispora is a white-rot basidiomycete that produces several isoenzymes of manganese peroxidase (MnP· ). A cDNA of one of them (MnP13-1) has been isolated and sequenced. The deduced aminoacid sequence shows about 60% similarity with the MnPs from Phanerochaete chrysosporium. Based on the crystal structures of MnP and lignin peroxidase (LiP) from P. chrysosporium, and of a peroxidase from Arthromyces ramosus (ARP), we have modeled by homology the three dimensional structure of MnP13-1 using standard modeling procedures. Local molecular mechanics optimization performed in the region corresponding to the binding sites of Ca2+ and Mn2+ in MnP13-1 demonstrated that the stereochemistry and the geometry of binding are conserved in both MnPs. A...
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000200006

Plant regeneration of Anthurium andreanum cv Rubrun
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vargas,Teresa E.; Mejías,Alexander; Oropeza,Maira; de García,Eva.
To establish an efficient regeneration system for Anthurium andreanum cv Rubrun, seeds from plant spadixes were germinated on a medium supplemented with 2.2 muM BA. After 2 weeks, 74% of the seeds germinated and four weeks later, micro-cuttings from these plantlets were subcultured on a medium containing 4.4 muM BA and 0.05 muM NAA. On average, 3.6 shoots per explant were obtained. Four weeks old in vitro plants from germinated seeds and the plantlets obtained from micro-cuttings, showed callus proliferation at the stem base. These tissues were subcultured on a medium supplemented with 8.9 muM BA and 2.7 muM NAA. After 6 weeks of culture, about 43.8 plantlets per square cm of callus were obtained. Anatomical studies showed the organogenic nature of these...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300010

Application of microsatellite markers for breeding and genetic conservation of herds of Pantaneiro sheep
Provedor de dados: Electronic Journal of Biotechnology
Autores: Crispim,Bruno do Amaral; Seno,Leonardo de Oliveira; Egito,Andréa Alves do; Vargas Junior,Fernando Miranda de; Grisolia,Alexéia Barufatti.
Background The aim of the present study was to assess the genetic diversity of Pantaneiro sheep, using microsatellite markers, in order to assist maintenance and management plans, enhance mating systems and reduce the inbreeding rate. A total of 127 animals were genotyped at eight microsatellite loci. They belonged to populations from the Experimental Farm of the Universidade Federal da Grande Dourados (UFGD) (Dourados/MS/Brazil) and Embrapa Pantanal (Corumbá/MS/Brazil). Results The population of Pantaneiro sheep from the UFGD exhibited a high mean number of alleles (11.13) and allelic richness (10.66). The polymorphic information content was highly informative in the locus studied, resulting in a mean value of 0.71. Observed heterozygosity was lower than...
Tipo: Journal article
Palavras-chave: Animal genetic resources; Genetic diversity; Kinship; Locally adapted breed; STR.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600010

High density process to cultivate Lactobacillus plantarum biomass using wheat stillage and sugar beet molasses
Provedor de dados: Electronic Journal of Biotechnology
Autores: Krzywonos,Magorzata; Eberhard,Thomas.
Background: Owing to the growing interest in biofuels, the concept of a biorefinery where biomass is converted to a variety of useful products is gaining ground. We here present how distillery waste is combined with a by-product from a sugar production, molasses, to form a medium for the growth of Lactobacillus plantarum with yields and biomass densities comparable with conventional industrial media. Such approach enables a cost-effective utilization of the problematic wastewater from ethanol and a by-product from sugar production. It is the first approach that attempts to find low-cost media for the production of Lactobacillus plantarum biomass. Results: This study suggests that sieved wheat stillage enriched by adding 1.77 g/l yeast extract and 10%...
Tipo: Journal article
Palavras-chave: Distillery wastewater; High density fermentation; Lactic acid bacteria; Lactobacillus plantarum; Sugar beet molasses; Wheat stillage.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200006

Genetic diversity analysis of rice cultivars (Oryza sativa L.) differing in salinity tolerance based on RAPD and SSR markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kanawapee,Nantawan; Sanitchon,Jirawat; Srihaban,Pranee; Theerakulpisut,Piyada.
Thirty rice cultivars were evaluated for salinity tolerance during the seedling stage and were divided into five tolerance groups including tolerant (T), moderately tolerant (MT), moderately susceptible (MS), susceptible (S) and highly susceptible (HS) which comprised 5, 10, 9, 4 and 2 cultivars respectively. Genetic diversity of all rice cultivars was evaluated using random amplified polymorphic DNA (RAPD) and simple sequence repeats (SSR) markers. The cultivars were evaluated for polymorphisms after amplification with 20 random decamer primers and 20 SSR primer pairs. A total of 161 RAPD markers and 190 SSR alleles were produced which revealed 68.94% and 89.47% polymorphism respectively. Mean genetic similarity coefficient was 0.82 for RAPD and 0.70 for...
Tipo: Journal article
Palavras-chave: Genetic similarity; RAPD markers; Rice; Salinity tolerance; SSR markers.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600002

Screening for propagation suitability in vitro of different Cyclamen species
Provedor de dados: Electronic Journal of Biotechnology
Autores: Seyring,Martina; Ewald,Aloma; Mueller,Anke; Haensch,Klaus-Thomas.
In the present study we examined the possibility of propagating different Cyclamen species (C. africanum Boiss. and Reut., C. cilicium Boiss. and Heldr., C. coum Mill., C. hederifolium Ait., C. persicum Mill., C. purpurascens Mill.) including some of their subspecies and cultivars in vitro using explants of adult plants. For this purpose two protocols have been applied to eleven genotypes combined with mostly four explant types (placentas with ovules, leaves, petioles and peduncles). The use of these protocols has given rise to either somatic embryo-like structures and/or adventitious shoots in all genotypes. This way it was possible to propagate each of the examined genotypes in vitro using explants of adult plants in a time less than one year. These...
Tipo: Journal article
Palavras-chave: Propagation; Shoot regeneration; Somatic embryogenesis; Species.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400010

Evaluating Colombian Clostridium spp. Strains hydrogen production using glycerol as substrate
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bernal,Mauricio; Tinoco,Lizeth K; Torres,Luz; Malagón-Romero,Dionisio; Montoya,Dolly.
Background: The ability for hydrogen production of 13 native strains of Clostridium spp. strains isolated from Colombian soil was evaluated using glycerol substrate. Glycerol to hydrogen conversion was investigated using a batch fermentation reactor and industrial glycerol source (50 g.l-1, pH 7.00). Results: The results were quantified regarding acids, hydrogen, biomass and solvent production. The selected strain gave good hydrogen over production output at 14.4 mmol H2.l-1, productivity 0.3167 mg H2.h-1 l-1 culture mediumand yield 0.1962 mol H2.mol-1 glycerol. A further fermentation assay a 4.0 liter batch reactor let to being 0.26 mg.l-1.h-1 after 18 hrs of fermentation. Logistic model, Luedeking-Piret model and Luedeking-Piret modified models were used...
Tipo: Journal article
Palavras-chave: Anaerobic fermentation biofuel Clostridium spp glycerol; Hydrogen mathematical model.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000200005

Changes in morpho-physiological attributes of Eucalyptus globulus plants in response to different drought hardening treatments
Provedor de dados: Electronic Journal of Biotechnology
Autores: Coopman,Rafael E; Jara,Jorge C; Bravo,Leon A; Sáez,Katia L; Mella,Gloria R; Escobar,Rene.
Morpho-physiological attributes exhibited in response to drought hardening at the end of the growing season of Eucalyptus globulus Labill under nursery conditions were studied to evaluate the effect of three drought hardening treatments in morpho-physiological traits used as suitable indicators of drought hardiness, such as, plant growth, root growth potential, plant water relationships and survival. Freezing resistance of drought hardened plants was also studied in order to evaluate cross hardening effects in cuttings of Eucalyptus globulus Labill. Drought hardening consisted in induced water stress by watering restriction, until plant stem xylem water potentials (&amp;#936;pd) reached to-0.2, -1.3 and -2.4 MPa. Two water stress-rewatering cycles were...
Tipo: Journal article
Palavras-chave: Freezing resistance; Root growth potential; Stem xylem water potential; Water stress; Water relationships.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200005

Visualisation of the microbial colonisation of a slow sand filter using an Environmental Scanning Electron Microscope
Provedor de dados: Electronic Journal of Biotechnology
Autores: Devadhanam Joubert,Esther; Pillay,Balakrishna.
The removal of contaminants in slow sand filters occurs mainly in the colmation layer or schmutzdecke - a biologically active layer consisting of algae, bacteria, diatoms and zooplankton. A ripening period of 6 - 8 weeks is required for this layer to form, during which time filter performance is sub-optimal. In the current study, an environmental scanning electron microscope was used to visualise the ripening process of a pilot-scale slow sand filter over a period of eight weeks. To achieve this, sand particles were removed at weekly intervals and observed for biofilm development. Biological mechanisms of removal in slow sand filtration are not fully understood. A visualisation of the colonisation process would enhance the knowledge and understanding of...
Tipo: Journal article
Palavras-chave: Biofilm; Microbial biodiversity; Schmutzdecke.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200014

Designing and validation of genus-specific primers for human gut flora study
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rekha,Rani; Alam Rizvi,Moshahid; Jaishree,Paul.
The aim of this study, was to design and validate 16S rRNA targeted oligonucleotide genus specific primers for amplifying the predominant members of gut flora using polymerase chain reaction. Primers were validated against human faecal samples. Gut flora of a normal individual was compared with that of two diseased individuals. Our observations showed that the genera Lactobacillus, Bacteroides, Peptococcus, Bifidobacterium, and E. coli were invariably present in all studied subjects however, the absence of butyrate producing bacteria Ruminococcus and Peptostreptococcus were significant. Presence of the members of the genus, Campylobacter in both the diseased samples were also unusual.
Tipo: Journal article
Palavras-chave: 16S rRNA based primers; Anaerobic bacteria; Diarrhoea patient; Polymerase chain reaction.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500005

Biotransformation of 1,8-cineole, the main product of Eucalyptus oils
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rodríguez,Paula; Sierra,Wilson; Rodríguez,Sonia; Menéndez,Pilar.
The forest industry in Uruguay has grown considerably during the last decade. Eucalyptus plantations account for 74% of the forested land, with Eucalyptus globulus being the most widely distributed species. This industry is dedicated exclusively to the production of wood without exploiting the by-products (leaves and small branches). Eucalyptus leaves are known to contain important amounts of essential oils composed primarily of 1,8-cineole (1,3,3-trymethyl-2-oxabicyclo[2.2.2]octane). In this work, the biotransformation of 1,8-cineole, is achieved using a native bacterium (Rhodococcus sp.) which was isolated from the soil of Eucalyptus forest. A 98% of bioconversion was achieved. Three different optically pure compounds were obtained, and they were...
Tipo: Journal article
Palavras-chave: Biocatalysis; Monoterpenes; Eucalyptus; Green Chemistry.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300011

Cloning and expression analysis of peanut (Arachis hypogaea L.) CHI gene
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Yue; Xia,Han; Yuan,Mei; Zhao,Chuanzhi; Li,Aiqin; Wang,Xingjun.
Chalcone isomerase (CHI) is the key enzyme that catalyzes chalcone into (2S)-flavanol or (2S)-5-desoxidation flavanol. The full length cDNA (1050 bp) of AhCHI (Arachis hypogaea CHI gene) was cloned by large scale EST sequencing using a peanut immature seed cDNA library. Sequence analysis results indicated that it was a type I CHI gene (with the accession number JN660794). The ORF of AhCHI was 768 bp, encoding a peptide of 255 amino acids with a pI of 5.189. Sequence alignment showed that the coding region of AhCHI gene is highly conserved to compare with CHI genes from other plant species. Peanut cDNA microarray and semi-quantitative RT-PCR analysis indicated that AhCHI was highly expressed in pegs. The expression level in flower and root was higher than...
Tipo: Journal article
Palavras-chave: Arachis hypogaea L.; CDNA library; Chalcone isomerase; Expression analysis.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000100005

Copper removal from aqueous solution by marine green alga Ulva reticulata
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vijayaraghavan,Kuppusamy; Raj Jegan,Joseph; Palanivelu,Kandasamy; Velan,Manickam.
The batch removal of copper (II) ions from aqueous solution under different experimental conditions using Ulva reticulata was investigated in this study. The copper (II) uptake was dependent on initial pH and initial copper concentration, with pH 5.5 being the optimum value. The equilibrium data were fitted using Langmuir and Freundlich isotherm model, with the maximum copper (II) uptake of 74.63 mg/g determined at a pH of 5.5. The Freundlich model regression resulted in high correlation coefficients and the model parameters were largely dependent on initial solution pH. At various initial copper (II) concentrations (250 to 1000 mg/L), sorption equilibrium was attained between 30 and 120 min. The copper (II) uptake by U. reticulata was best described by...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000100009

Declaration of Goiania by REDBIO/FAO: "Towards a biotechnology at the service of sustainable development of the Latin America and the Caribbean forestry and agricultural sectors"
Provedor de dados: Electronic Journal of Biotechnology
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000100001

Inhibitory effect of lotus seedpod oligomeric procyanidins on advanced glycation end product formation in a lactose-lysine model system
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wu,Qian; Li,Shu-Yi; Yang,Ting; Xiao,Juan; Chu,Qian-Mei; Li,Ting; Xie,Bi-Jun; Sun,Zhi-Da.
Background Industrial food processing induces protein glycation modifications and toxic advanced glycation end products (AGEs) which affect human health. Therefore, it is of interest to monitor AGEs in food processing. The present study was carried out to investigate the influence of lotus seedpod oligomeric procyanidin (LSOPC) concentrations, solution pH value and metal ions on AGE formation by heat treatment of lactose-lysine model solutions. Ne-(carboxymethyl) lysine (CML), as one of the common AGEs was also determined by HPLC-MS/MS in this experiment. Results The results showed that LSOPC can inhibit the formation of AGEs effectively at higher concentrations, lower temperature, and it can reverse the promotion function of metal ions because of its high...
Tipo: Journal article
Palavras-chave: Advanced glycation end products (AGEs); Lactose; Lotus seedpod oligomeric procyanidins (LSOPC); Lysine; Maillard reaction.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200002

Identification of alternate dwarfing gene sources to widely used Dee-Gee-Woo-Gen allele of sd1 gene by molecular and biochemical assays in rice (Oryza sativa L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Neeraja,Chirravuri Naga; Vemireddy,Lakshminarayana Reddy; Malathi,Surapaneni; Siddiq,Ebrahimali Abubacker.
After the success of IR8 and TN1, breeders depended heavily on these two rice cultivars for source of short stature led to the narrow genetic base to majority of present day rice varieties, as far as sd1 (semi-dwarf1) gene is concerned. In addition, analysis of genetic lineage of the majority of the cultivated rice varieties in tropical Asia reveals that sd1 from DGWG (Dee-Gee-Woo-Gen) is the major source of dwarfing gene. Such high amount of genetic homogeneity renders rice plants vulnerable to epidemic of diseases and insect pests. In the current study, we made an attempt to identify the alternate sources of DGWG allele of sd1 gene by characterizing 29 induced and 3 spontaneous dwarf accessions employing marker for DGWG allele of sd1 gene and exogenous...
Tipo: Journal article
Palavras-chave: Dee-Gee-Woo-Gen; Dwarfing gene; Gibberellic acid assay; Molecular marker; Rice; Sd1 gene.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300007

Comparison of two total RNA extraction protocols using the marine gorgonian coral Pseudopterogorgia elisabethae and its symbiont Symbiodinium sp.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Santiago-Vázquez,Lory Z.; Ranzer,Llanie K.; Kerr,Russell G.
Marine invertebrates such as soft corals are important sources of secondary metabolites with promising biomedical applications and commercial value. RNA isolation in conjunction with reverse-transcriptase polymerase chain reaction (RT-PCR) are valuable tools utilized to study the molecular elements involved in secondary metabolite production and functional genomics. Two total RNA extraction protocols were compared using fresh tissue and flash frozen preparations from the coral Pseudopterogorgia elisabethae and from its symbiont Symbiodinium sp. isolated using RNeasy minicolumns (&lt;a href="http://www1.qiagen.com/SelectCountry.aspx"&gt;Qiagen®&lt;/a&gt;) and Trizol reagent (&lt;a href="http://www.invitrogen.com/"&gt;Invitrogen®&lt;/a&gt;). In general,...
Tipo: Journal article
Palavras-chave: Dinoflagellate; RNA isolation; RNeasy minicolumns; Trizol reagent.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500017

Association between AA-NAT gene polymorphism and reproductive performance in sheep
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ding-ping,Bai; Cheng-jiang,Yu; Yu-lin,Chen.
Arylalkylamine N-acetyltransferase (AA-NAT) is critical enzyme in Melatonin (MLT) biosynthesis for MLT regulating the animal seasonal breeding. In this study, DNA sequencing methods were applied to detect the polymorphisms of the AA-NAT gene in 179 Chinese sheep belonging to two non-seasonal reproduction breeds and two seasonal reproduction breeds. One mutation at exon 3 (NM_001009461:c.486A &amp;gt; G) was &amp;#64257;rstly described at the sheep AA-NAT locus. Hence, we described the SmaI PCR-RFLP method for detecting EX3 486A &amp;gt; G mutation, frequencies of the AA-NAT-G allele varied from 0.871 to 0.908 in two non-seasonal reproduction breeds and 0.517 to 0.578 in two seasonal reproduction breeds. The associations of SmaI polymorphism with estrus...
Tipo: Journal article
Palavras-chave: AA-NAT gene; Polymorphism; Reproduction; Seasonality; Sheep.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000200007

Molecular analysis of genetic stability in long-term micropropagated shoots of banana using RAPD and ISSR markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lakshmanan,Venkatachalam; Reddampalli Venkataramareddy,Sreedhar; Neelwarne,Bhagyalakshmi.
A large number of micropropagated plantlets of banana, Musa acuminata var. Nanjanagudu Rasabale (NR), that were developed from axillary shoot bud explants over 10 years ago were screened for genetic variation, if any, using RAPD (Random Amplified Polymorphic DNA) and ISSR (Inter-Simple Sequence Repeats) markers. Of the 4000 in vitro plantlets, 11 were used for screening that involved shoot cultures with distinct variation in morphological characteristics (morphotypes). Similarly, the mother maintained in the field was also subjected for genetic analysis. Out of the 50 RAPD and 25 ISSR primers screened, 30 RAPD and 5 ISSR primers produced totally 424 clear, distinct and reproducible band classes resulting in a total of 5088 bands where the banding patterns...
Tipo: Journal article
Palavras-chave: Growth regulators; Musa; Protocol; Shoot cultures; Somaclonal variation.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100010

Assessment of genetic diversity in sesame (Sesamum indicum L.) detected by Amplified Fragment Length Polymorphism markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ali,Ghulam M; Yasumoto,Sirato; Seki-Katsuta,Masumi.
Sesame (Sesamum indicum L.) is one of the oldest oil crops and is widely cultivated in Asia and Africa. To determine the level of genetic diversity in relation to geographical origins and morphological characteristics, a total of 96 accessions have been collected from different parts of the world and were analyzed using AFLP techniques. Twenty-one primer pairs generated a total of 445 bands and among them 157 (35%) were polymorphic. Using UPGMA clustering analysis method based on the similarity coefficient, accessions were separated into two major groups. The first group mostly consists of Eastern Asian origin and another group consists of South Asian origin. Sub-clusters separated the accessions and form distinct diversity among groups. Considering the...
Tipo: Journal article
Palavras-chave: AFLP; Genetic diversity; Geographical origin; Morphology; Sesame.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100002

A simple ethanol wash of the tissue homogenates recovers high-quality genomic DNA from Corchorus species characterized by highly acidic and proteinaceous mucilages
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kundu,Avijit; Sarkar,Debabrata; Bhattacharjee,Amit; Topdar,Niladri; Sinha,Mohit Kumar; Mahapatra,Bikash Sinha.
A simple miniprep based on early elimination of highly acidic and proteinaceous mucilages through ethanol washing of the tissue homogenates has been developed for the extraction of genomic DNA from mature leaves and seeds of Corchorus spp. As compared to high cetyltrimethylammonium bromide (CTAB)-NaCl DNA extraction followed by ethanol-based removal of remnant mucilages from the DNA pellet, this simple miniprep consistently and reproducibly recovers high amounts of DNA with good spectral qualities at A260/A280 and A260/A230. The purified DNA is efficiently digested by restriction endonucleases, and is suitable for PCR amplification of nuclear microsatellites with expected allele sizes.
Tipo: Journal article
Palavras-chave: Corchorus; DNA extraction; Microsatellite; Mucilage; PCR; Restriction digestion.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100010

Environmental and Industrial Biotechnology in Developing Countries
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kryl,David.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300003

The power of 28 microsatellite markers for parentage testing in sheep
Provedor de dados: Electronic Journal of Biotechnology
Autores: Al-Atiyat,Raed M.
Background In sheep breeding, there are situations where relationships recorded at the farm among pedigrees such as parent-offspring, full-sibs or half-sibs need to be tested. A panel of 28 microsatellite (MST) markers was tested to provide accurate pedigree information and resolve the common problem of significant error in pedigree records in Merino sheep. Three different flocks of Australian Merino sheep were investigated. A private farm flock represents a flock with no record availability. Two other flocks were maintained under good managements of full keeping records and being selected for high and low parasite resistances. Results In the studied panel, eight MSTs provided an average of Polymorphic Information content (PIC) equal to 0.65 or more in...
Tipo: Journal article
Palavras-chave: Merino sheep; Paternity verification; Pedigree records; SSR markers.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200009

GMO-Technology and Malnutrition Public Sector Responsibility and Failure
Provedor de dados: Electronic Journal of Biotechnology
Autores: Potrykus,Ingo.
Tipo: Journal article
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300001

Isolation of the intracellular and extracellular polysaccharides of Ganoderma neojaponicum (Imazeki) and characterization of their immunomodulatory properties
Provedor de dados: Electronic Journal of Biotechnology
Autores: Nik Ubaidillah,Nik Hafizah; Abdullah,Noorlidah; Sabaratnam,Vikineswary.
Background The role of polysaccharides isolated from the Ganoderma species of fungi in innate immunity has recently become a topic of research. Although some work has been conducted concerning Ganoderma lucidum, the characteristics of polysaccharides isolated from Ganoderma neojaponicum (Imazeki) as immunomodulatory agents are largely unknown. The aims for this study were to isolate and characterize the intracellular polysaccharides (IPSs) and extracellular polysaccharides (EPSs) of G. neojaponicum from STR reactor. Results The production of EPS and IPS was optimized on day 4 of the cultivation time in 2 L STR reactor based on the amount of biomass yield, total carbohydrate, &amp;#946;-glucan and a-glucan content. Further analysis, both the EPSs and IPSs...
Tipo: Journal article
Palavras-chave: &amp;#946; -Glucan Acute oral toxicity Macrophage cell line Phagocytosis Stirred tank reactor Total carbohydrate.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300008

Effects of oligosaccharides from endophytic Fusarium oxysporum Dzf17 on activities of defense-related enzymes in Dioscorea zingiberensis suspension cell and seedling cultures
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Peiqin; Luo,Haiyu; Meng,Jiajia; Sun,Weibo; Wang,Xiaohan; Lu,Shiqiong; Peng,Youliang; Zhou,Ligang.
Background Three oligosaccharides (EOS, WOS and SOS) were respectively prepared from the corresponding polysaccharides, namely exopolysaccharide (EPS), water-extracted mycelial polysaccharide (WPS) and sodium hydroxide-extracted mycelial polysaccharides (SPS) from the endophytic fungus Fusarium oxysporum Dzf17. In this study, the effects of EOS, WOS and SOS on the activities of the defense-related enzymes, namely phenylalanine ammonia lyase (PAL), polyphenoloxidase (PPO) and peroxidase (POD) in its host plant Dioscorea zingiberensis cultures were investigated. Results For the suspension cell cultures of D. zingiberensis, the highest PAL activity was induced by 0.5 mg/mL of WOS at 48 h after treatment, which was 4.55-fold as that of control. Both PPO and...
Tipo: Journal article
Palavras-chave: Endophytic fungus; Phenylalanine ammonia lyase; Peroxidase; Polyphenoloxidase; Polysaccharide.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000400003

Chromosomal localization of selected SCARs converted from new RAPD, ISSR and R-ISSR markers linked to rye (Secale cereale L.) tolerance to nutrient deprivation stress identified using bulk segregant analysis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Smolik,Milosz.
Background: An adaptive mechanism in plant roots is initiated in the event of nitrogen and potassium deficiency, and it facilitates the active uptake of these elements in order to ensure plant growth and survival in stress conditions. Signaling and transduction of signals in response to changing nitrogen and potassium concentrations is a complex process, affected by interactions between various gene expression products, and often subjected to modifications. Results: In order to identify genotypic differences between phenotypes of two populations of recombinant inbred rye lines (153/79-1 x Ot1-3 and Ot0-6 x Ot1-3) in response to nutrition stress caused by nitrogen and potassium deficiency at the seedling stage, bulk segregant analysis was utilized....
Tipo: Journal article
Palavras-chave: Molecular markers; Nutrient deficiencies; Orthologs; Response; RILs; Rye; TIGR; TOGA.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500001

Biotechnology in Argentine agriculture faces world-wide concentration
Provedor de dados: Electronic Journal of Biotechnology
Autores: Varela,Liliana; Bisang,Roberto.
In the 1980s, the technical pattern of production in agriculture changed due to the increasing design of genetically modified plants. Modern biotechnology thrived on events requiring certain thresholds of scientific and technological skills as well as scale economies usually seen in developed countries. The mergers and acquisitions during the mid-1990s led to a world-wide oligopoly composed of very few agri-biotechnological mega-corporations and the literature discusses the impact of the mergers and acquisitions on the agriculture of developing countries with comparative advantages in agriculture. This paper analyzes the world-wide process of agri-biotechnological mega-corporation mergers and acquisitions as well as its impact and interrelationships with...
Tipo: Journal article
Palavras-chave: Internalization; Local adaptation; Mergers and acquisitions; Multinationals.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300010

Can painting human cells with exogenous maltoporin enable efficient therapeutic gene transfer by bacteriophage lambda vectors?
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tolmachov,Oleg.
Many gene therapy strategies require transfer of high-molecular weight DNA into human cells. To enable clinical trials, these vectors need to be produced on a large scale and at low cost. The production of effective high-capacity vectors like HSV-amplicons and helper-dependent adenoviral vectors is difficult to up-scale, so new inexpensive vectors are needed for the efficient delivery of high-molecular weight DNA to human cells. Bacteriophage lambda vectors can accommodate up to about 46 kb of therapeutic DNA and can be easily produced in an industrial setting. However, the lambda vectors transfer DNA into mammalian cells with only a low efficiency. It was shown that bacteriophage lambda virions ejected their DNA in the presence of the purified receptor...
Tipo: Journal article
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400012

Inter simple sequence repeats separate efficiently hemp from marijuana (Cannabis sativa L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hakki,Erdogan E; Kayis,Seyit A; Pinarkara,Emine; Sag,Ayla.
Cannabis sativa L. is a multiple-use plant that provides raw material for the production of seed oil, natural fiber for textiles, automotive and pulp industries. It has also been used in insulating boards, ropes, varnishes, animal feed, and as medicinal agents. Cannabis has potential to be used for phytoremediation: however, its cultivation is strictly controlled due to its psychoactive nature and usage in producing drugs such as marijuana, and hashish. In this study, psychoactive type Cannabis samples, which were seized from 23 different locations of Turkey, and nine hemp type Cannabis accessions, as well as an unknown accession were used. Our interest was to identify the genetic relatedness of the seized samples and to separate drug and hemp type plants....
Tipo: Journal article
Palavras-chave: Cluster analysis; Hemp; ISSR; Marijuana; Principle coordinate analysis.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400010

Plant protease inhibitors in control of phytophagous insects
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lawrence,Paulraj K.; Koundal,Kripa Ram.
Plant proteinase inhibitors (PIs) have been well established to play a potent defensive role against predators and pathogens. Although diverse endogenous functions for these proteins has been proposed, ranging from regulators of endogenous proteinases to act as storage proteins, evidence for many of these roles is partial, or confined to isolated examples. On the other hand, many PIs have been shown to act as defensive compounds against pests by direct assay or by expression in transgenic crop plants, and a body of evidence for their role in plant defense has been accumulated consistently. The role and mechanism of action for most of these inhibitors are being studied in detail and their respective genes isolated. These genes have been used for the...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100014

Analysis of gene expression in Kalanchoe daigremontiana leaves during plantlet formation under drought stress
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhong,Tianxiu; Zhu,Chen; Zeng,Huiming; Han,Liebao.
Background: Kalanchoe daigremontiana is an attractive model system for the study of the molecular mechanisms of somatic embryogenesis and organogenesis competence due to its formation of plantlets with adventitious roots on the leaf margins that are derived from somatic embryos. The suppression subtractive hybridization technique was used to investigate gene expression during asexual reproduction. Leaves from plants subjected to drought stress provided the source of &amp;#8216;Tester&amp;#8217; DNA, and leaves from plants grown under normal conditions provided the &amp;#8216;Driver&amp;#8217; DNA for subtractive hybridization. Results: A total of 481 high quality ESTs were generated, which clustered into 390 unigenes. Of these unigenes, 132 grouped into 12...
Tipo: Journal article
Palavras-chave: Bioinformatics analysis; Real time PCR; Suppression subtractive hybridization.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600004

Enhancement of wanlongmycin production by nitrogen ion beam implantation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Xiaoyong; Lin,Birun; Gao,Xiangyang; Shen,Huifang.
In an attempt to obtain an industrial strain with higher yield of wanlongmycin, the wild strain Streptomyces griseovariabilis GAAS2507 was mutated by a novel mutagen, nitrogen ion beam with energy of 20 kilo electron volts (KeV) and dose ranging from 7.80 x 10(14) to 2.86 x 10(15) ions/cm². One mutant strain WN939 was obtained. Its yield of wanlongmycin reached 271.24 µg/mL, which was 82.10% higher than that of the wild strain. The mutant strain WN939 was relatively stable for the production of wanlongmycin through six successive transfers of cultures and a repeat fermentation in a 30 L fermentor. In addition, the mutant strains were investigated and divided into five types by their colony phenotypes and production of wanlongmycin. Among them, three types...
Tipo: Journal article
Palavras-chave: Mutagen nitrogen ion beam implantation; Streptomyces griseovariabilis GAAS2057; Wanlongmycin.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100003

Improved isolation of good-quality total RNA from the optic stalk of Mud crab, Scylla paramamosain
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhu,Houze; Jiang,Keji; Zhang,Fengying; Zhang,Dan; Pi,Yan; Ma,Lingbo.
An improved and efficient protocol was developed based on the TaKaRa RNAiso Plus Kit (Code: D9108A) for isolating good-quality total RNA from the optic stalk of mud crab, Scylla paramamosain. The protocol was based on the Trizol method with modifications. The carapace overlapping the optic stalk was retained with RNA in regular protocol. In order to remove the abundant deposition correlative with the carapace which makes the isolation of RNA particularly difficult, 5M potassium acetate solution (pH = 6.0) was added before the precipitation of RNA, and the temperature of RNA deposition was also decreased to -70ºC to ensure the stabilization of RNA. Good-quality total RNA from the optic stalk of S. paramamosain could be easily isolated with this modified...
Tipo: Journal article
Palavras-chave: Optic stalk; Potassium acetate; RNA isolation; Scylla paramamosain.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000200005

Efficient transformation of Penicillium chrysogenum mediated by Agrobacterium tumefaciens LBA4404 for cloning of Vitreoscilla hemoglobin gene
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sun,Chuan-Bao; Kong,Qiu-Lian; Xu,Wen-Si.
The vgb and bleomycin resistance genes could be efficiently transferred into the filamentous fungus Penicillium chrysogenum under help of T-DNA of Agrobacterium tumefaciens LBA4404 and the transferred genes were integrated at a chromosomal locus of P. chrysogenum. Transformation using A. tumefaciens LBA4404 could be enhanced in the presence of acetosyringone (AS) when being carried out in the conidiaand mycelium. The efficiencies of transformation could be improved up to 10 folds compared with conventional techniques for transformation of P. chrysogenum protoplasts.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100009

Bionanoparticles, a green nanochemistry approach
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cauerhff,Ana; Castro,Guillermo R.
Background: In the past decade, considerable attention has been paid for the development of novel strategies for the synthesis of different kind of nano-objects. Most of the current strategies are usually working by the use physical or chemical principles to develop a myriad of nano-objects with multiple applications. Main fields of nanotechnology applications range from catalysis, micro- and nano-electronics (semiconductors, single electrons transistors), non-linear optic devices, photo-electrochemistry to biomedicine, diagnostics, foods and environment, chemical analysis and others. Results: Two main avenues for nanoparticles synthesis: cell-free extract and cell cultivation have been reported. The state of art of both biotechnological approaches for...
Tipo: Journal article
Palavras-chave: Bacteria; Bionanoparticles; Fermentation; Fungi green chemistry; Plant extracts.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300011

Characterization and comparability of biosimilars: A filgrastim case of study and regulatory perspectives for Latin America
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mendoza-Macedo,Karina; Romero-Díaz,Alexis J; Miranda-Hernández,Mariana P; Campos-García,Víctor R; Ramírez-Ibañez,Nancy D; Juárez-Bayardo,L. Carmina; Moreno-Duran,Karen; Cedillo-Robles,Miriam S; Pérez,Nestor O; Jung-Cook,Helgi; Flores-Ortiz,Luis F; Medina-Rivero,Emilio.
Background: Developing countries have an estimate of ten times more approved biosimilars than developed countries. This disparity demands the need of an objective regulation that incorporates health policies according to the technological and economical capabilities of each country. One of the challenges lies on the establishment of comparability principles based on a physicochemical and biological characterization that should determine the extent of additional non-clinical and clinical studies. This is particularly relevant for licensed biosimilars in developing countries, which have an extensive clinical experience since their approval as generics' in some cases more than a decade. To exemplify the current status of biosimilars in Mexico' a...
Tipo: Journal article
Palavras-chave: Bio therapeutic; Comparability; Critical quality attributes; Developing countries; Generics; Health policies; High quality biosimilars; Regulation.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600010

Encouraging generic skills in science courses
Provedor de dados: Electronic Journal of Biotechnology
Autores: Johnson,Elizabeth; Herd,Susanna; Tisdall,Judith.
Generic skills are skills that are common to all graduates rather than specific for a particular field of study. They include communication and problem-solving skills and the ability to work successfully in teams. To produce graduates with these skills, university courses must include exercises that encourage development of these skills and assessment procedures which reward achievement in these areas. This paper describes three simple exercises designed to develop generic skills that can easily be incorporated into existing courses.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200004

The influence of centrifugation on Zymomonas mobilis aggregation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Perez Fernandez Palha,María de los Angeles; Edison Lopes,Carlos; Gomes de Andrade Lima,Maria Alice; Pereira Junior,Nei.
Flocculent Zymomonas mobilis breaks down in smaller flocs and individual cells when centrifuged. The main consequence of it is an increase in the dispersion of the sample, suggesting that the influence of the centrifugal force on the aggregation of cells is worth to study. The experiments showed that the degree of dispersion varied between 30% and 100% when the centrifugal acceleration changed from 25 g to 2500 g. Observation under the electronic microscope showed that a slimy material covered the cells recovered by gentle gravitational settling and, that the centrifuged cells presented a bare cell wall.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300011

Optimization of the citric acid production by Aspergillus niger through a metabolic flux balance model
Provedor de dados: Electronic Journal of Biotechnology
Autores: Guebel,Daniel V.; Torres Darias,Néstor V.
Idiophase, the citric acid producing stage of Aspergillus niger was mathematically modeled to identify required genetic manipulations to optimize citric acid production rate. For this reason, a consistent picture of cell functioning had to be achieved. The transient idiophase nature was established by stoichiometric analysis. The main intracellular fluxes were computed by application of material and physiological constraints (ATP, reduction equivalents, proton motive force) at culture time 120 hours. The HMP pathway accounts for 16% of the glucose input (carbon basis), the Krebs cycle for 13% and the citric acid synthesis for the remaining 71%. This profile implies an operative glycerol-P shuttle. It recycles 93% of the cytosolic glycerol-P to cytosolic...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000100001

Safe use of genetically modified lactic acid bacteria in food: Bridging the gap between consumers, green groups, and industry
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sybesma,Wilbert; Hugenholtz,Jeroen; de Vos,Willem M.; Smid,Eddy J.
Within the European Union (EU), the use of genetically modified organisms (GMOs) in food production is not widely applied and accepted. In contrast to the United States of America, the current EU legislation limits the introduction of functional foods derived from GMOs that may bring a clear benefit to the consumer. Genetically modified lactic acid bacteria (GM-LAB) can be considered as a different class of GMOs, and the European Union is preparing regulations for the risk assessment of genetically modified microorganisms. Since these procedures are not yet implemented, the current risk assessment procedure is shared for GMOs derived from micro organisms, plants, or animals. At present, the use of organisms in food production that have uncontrolled genetic...
Tipo: Journal article
Palavras-chave: Lactic acid bacteria; Genetic modification; Legislation; Novel foods; Safety assessment.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400011

In vitro fruit trees rooting by Agrobacterium rhizogenes wild type infection
Provedor de dados: Electronic Journal of Biotechnology
Autores: Damiano,Carmine; Monticelli,Simona.
Agrobacterium rhizogenes infection at the base of microcuttings in vitro can improve the rooting of some fruit species. A study was carried out comparing rooting of almond, apple, plum, Pyrus pyraster and two hybrid rootstocks, when infected with A. rhizogenes strain 1855, with and without the addition of hormones. Three responses occurred: genotypes rooted without auxins; genotypes rooted only with auxins; genotypes rooted only after infection. All genotypes rooted after bacterial infection. In the first group the auxins increased rooting percentages. No substantial differences were found with and without infection in hormone free media, while the rooting percentages tended to decrease with the combination auxin/infection. In the second group, infection...
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000300008

Effect of Brachionus rubens on the growth characteristics of various species of microalgae
Provedor de dados: Electronic Journal of Biotechnology
Autores: Abou,Reda A.I; Singh,Manjinder; Rivera-Cruz,Anangelica; Power,Grace; Bagby-Moon,Thomas; Das,Keshav.
Background: Cultivation of algae for conversion to biofuels has gained global interest. Outdoor raceway cultivation is preferred because of its lower capital and operating costs. A major disadvantage of outdoor cultivation is susceptibility of algal crops to attack by predatory rotifers. In order to quantify the impact of rotifer attack on different species of algae, we evaluated the growth of eleven microalgal species over a 21-d period after being infected by the predatory rotifer Brachionus rubens. Results: Of the eleven species, Chlorella sorokiniana was the most susceptible with rapid decline in algal growth concomitant with increase in rotifer population growth (3.82/d). In contrast, Synechococcus elongatus andScenedesmus dimorphus were both...
Tipo: Journal article
Palavras-chave: Algae; Biofuels; Biomass; Cyanobacteria; FlowCam; Grazer.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400010

Analysis of genetic variability by ISSR markers in Calibrachoa caesia
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pérez de la Torre,Mariana; García,Martín; Heinz,Ruth; Escandón,Alejandro.
Background: Calibrachoa Cerv. (ex La Llave &amp;amp; Lexarza) is a genus of the Solanaceae family (La Llave and Lexarza, 1825). This genus has a high ornamental and economic value due to its intrinsic variability and multiplicity of flower colours. In Argentina there are eight native species, and one of them is Calibrachoa caesia. The genetic diversity among 35 accessions of C. caesia, from five departments in the province of Misiones, was analyzed using ISSR markers. Results: Thirteen ISSR primers yielded a reproducible banding pattern, with 701 amplified loci and 98% of polymorphism. The ISSR primers 5’CT, 5’CA, 5’GA, 5’GACA, 3’CAC, 3’TG and 3’TC generated 100% polymorphic patterns. The Rp values ranged from 23.20 to 10.29 for 5’GACA and 3’AG primers,...
Tipo: Journal article
Palavras-chave: Anchored microsatellites; Molecular markers; Ornamental plants.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500008

Cloning, characterization and expression of Peking duck fatty acid synthase during adipocyte differentiation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ding,Fang; Yuan,Xin; Li,Qingqing; Sun,Wenqiang; Gan,Chao; He,Hua; Song,Chenling; Wang,Jiwen.
Background Fatty acid synthase (FAS) is a key enzyme of de novo lipogenesis (DNL), which has been cloned from several species: Gallus gallus, Mus musculus, Homo sapiens, but not from Anas platyrhynchos. The current study was conducted to obtain the full-length coding sequence of Peking duck FAS and investigate its expression during adipocyte differentiation. Results We have isolated a 7654 bp fragment from Peking duck adipocytes that corresponds to the FAS gene. The cloned fragment contains an open reading frame of 7545 bp, encodes a 2515 amino acid protein, and displays high nucleotide and amino acid homology to avian FAS orthologs. Twelve hour treatment of oleic acid significantly up-regulated the expression of FAS in duck preadipocytes (P &lt; 0.05)....
Tipo: Journal article
Palavras-chave: Expression pattern; FAS; Oleic acid; Peking duck.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600001

Production of lignocellulolytic enzymes by Aspergillus niger biofilms at variable water activities
Provedor de dados: Electronic Journal of Biotechnology
Autores: Villena,Gretty K; Gutiérrez-Correa,Marcel.
Lignocellulolytic enzyme production by Aspergillus niger was compared both in submerged fermentation (SF) and biofilm fermentation (BF) at varying water activities. Maximal filter paper activity, endoglucanase and xylanase activities were much higher in BF (2.96, 4.7 and 4.61 IU ml-1, respectively) than in SF cultures (1.71, 1.31 and 2.3 IU ml-1, respectively) but biomass yields were lower in BF than in SF (0.338 g g-1 and 0.431 g g-1, respectively). In the presence of 20% ethylene glycol (a w = 0.942) the enzyme activities decreased in both systems but BF still had higher levels (1.0, 1.0 and 2.6 IU ml-1, respectively) than SF cultures (0.6, 0.7 and 1.5 IU ml-1, respectively). An increase in xylanase specific activity of more than 2 fold (from 4.2 to 10.2...
Tipo: Journal article
Palavras-chave: Biofilm; Cellulase; Ethylene glycol; Water activity; Xylanase.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100012

Cre-loxP recombination vectors for promoter studies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pedersen,Nina; Tuxen Poulsen,Thomas; Skovgaard Poulsen,Hans.
For promoter studies the cloning, subcloning and transfer to different plasmid vectors usually requires use of restriction enzymes and ligation reactions. One obstacle is the nucleotide polymorphisms of eukaryotic genomic DNA, which has the consequence that a sequence often differs from published sequences. Therefore sequencing, rigorous restriction enzyme analysis or introduction of suitable sites has to be performed prior to cloning and subcloning. In addition, conventional methods using restriction enzymes, insert purifications and ligations is expensive and labour demanding. We have developed a fast, efficient and inexpensive Cre recombinase-loxP based method, which allows cloning of promoter regions and subcloning of these into a variety of vectors in...
Tipo: Journal article
Palavras-chave: Cloning; Cre recombinase; Plasmid; Reporter genes; Therapeutic genes.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200013

Minibioreactor-gas collector for determining bacteria-produced hydrogen sulfide
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hernández García,Armando; Pimentel Vázquez,Eulogio; Mena Campos,Jesús.
A simple and economical minibioreactor-gas collector system for determination of hydrogen sulfide produced by a microorganism was designed. The detection of hydrogen sulfide was based on the reaction between the hydrogen sulfide in the gas stream from the culture, and a lead acetate solution 0.090 mol/L, contained in a tube gas collector; the conductimetric back titration of lead excess was made, and hydrogen sulfide was quantified indirectly, being the detection limit 0.5 µmol. The developed system was applied using Tsukamurella paurometabola DSM 20162 as a model, being the amount of hydrogen sulfide produced, 1.2 µmol in 24 hrs.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300007

Gene expression and characterization of 2-keto-3-deoxy-gluconate kinase, a key enzyme in the modified Entner-Doudoroff pathway of Serratia marcescens KCTC 2172
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lee,Yong-Seok; Park,In-Hye; Yoo,Ju-Soon; Kim,Hae-Sun; Chung,Soo-Yeol; Chandra,Muni Ramanna GariSubhosh; Choi,Yong-Lark.
We cloned 2-keto-3-deoxy-gluconate kinase (KDGK), which catalyzes the phosphorylation of 2-keto-3-deoxygluconate (KDG) to 2-keto-3-deoxy-6-phophogluconate (KDPG) from Serratia marcescens KCTC 2172. The nucleotide sequence revealed a single open reading frame containing 1,208 bp and encoding for 309 amino acids, with a molecular weight of 33,993 Da. The enzyme was purified via GST affinity chromatography. The putative KdgT binding site was detected upstream of the initial codon. The KDG kinase utilized 2-ketogluconate (KG) and KDG as substrates. The optimal temperature and pH for KDGK activity were 50ºC and 8.0, respectively.
Tipo: Journal article
Palavras-chave: 2-keto-3-deoxygluconate kinase; Carbohydrate kinase; Purification; Serratia marcescens KCTC 2172.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300005

Biotechnology in Developing Countries: Harnessing the Potential of High-TECH SMES in the Face of Global Competition
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bustamante,Pedro I.; Bowra,Steve.
In the global market, the emergence of new technologies are representing opportunities and challenges to both industry and the public sector of the Latin American Countries (LAC). Some of these technologies have far reaching implications for a large number of industrial sectors, creating wealth and employment, resulting in an increased competitiveness of the developed economies around the world. Modern biotechnology is one of these key emerging technologies which LAC must harness successfully to sustain economic growth and competitiveness. The ability to commercially exploit research in this area is also of prime importance. Developed countries have made important progress in recent years, with a strong leadership of USA in this sector. Unless substantial...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300001

The use of chitosan in protecting wooden artifacts from damage by mold fungi
Provedor de dados: Electronic Journal of Biotechnology
Autores: El-Gamal,Rehab; Nikolaivits,Efstratios; Zervakis,Georgios I; Abdel-Maksoud,Gomaa; Topakas,Evangelos; Christakopoulos,Paul.
Background: Many buildings in Egypt e.g. museums, mosques and churches, do not possess controlled environments for minimizing the risks of damage of wooden artifacts due to the growth of fungi. Fungal damage usually appears as change in wood color, appearance of stains, and sometimes deformation of wooden surfaces. In this study we focused on the effect that some fungi exert on the properties of wooden artifacts and evaluated the effectiveness of different concentrations of chitosan on their protection against damage by mold fungi. Results: Samples were collected from different monuments and environments, and fungi growing on them were isolated and identified. The isolated Penicillium chrysogenum, Aspergillus flavus and /Aspergillus niger strains were used...
Tipo: Journal article
Palavras-chave: Archeological wood; Chitosan protection; Crystallinity index; Damage of wooden artifacts; Filamentous fungi; FTIR; Fungal damage; Prevention of fungal growth; UV spectrophotometry; Wood deterioration; XRD.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600011

Performance of biofilm carriers in anaerobic digestion of sisal leaf waste leachate
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mshandete,Anthony Manoni; Björnsson,Lovisa; Kivaisi,Amelia Kajumulo; Rubindamayugi,Mugassa Steven Thomas; Mattiasson,Bo.
Three methanogenic biofilm bioreactors were studied to evaluate the performance of three types of carriers. The carrier material were consisted of sisal fibre waste, pumice stone and porous glass beads, and the bioprocess evaluated was the methanogenesis anaerobic digestion of sisal leaf waste leachate. Process performance was investigated by increasing the organic loading rate (OLR) step-wise. The best results were obtained from the bioreactor packed with sisal fibre waste. It had the highest chemical oxygen demand (COD) removal efficiencies in the range of 80-93% at OLRs in the range of 2.4-25 g COD L-1d-1. The degradation pattern of volatile fatty acids (VFAs) showed that the degradation of propionate was limiting at higher OLRs. The stable pH and...
Tipo: Journal article
Palavras-chave: Biogas; Methanogenesis; Packed-bed bioreactors; Packing media.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100009

Towards genetic transformation of local onion varieties
Provedor de dados: Electronic Journal of Biotechnology
Autores: Marinangeli,Pablo; Deluchi,Bernardo; Ríos,Raúl; Franzone,Pascual; Galmarini,Claudio; Rosselló,Fernando; Curvetto,Néstor.
The aim of this work was to explore the possibility of obtaining transgenic plants of onion varieties cultivated in Argentina, starting from calli induced from mature zygotic embryos, using two strains of Agrobacterium tumefaciens as transfection vectors. Mature embryos from three varieties of 'Valenciana' onion, Torrentina, Cobriza INTA and Grano de oro were in vitro cultivated for callus induction. After three to four months an average of 57.4% success for the three varieties was reached. Transformation was carried out with Agl1 or LBA 4404 A. tumefaciens strains, both carrying a binary vector containing the marker gene gus a and the selection gene nptII. Selection was done in callus induction medium containing 10 mgL-1 geneticin during three...
Tipo: Journal article
Palavras-chave: Agrobacterium tumefaciens; Allium cepa L.; Callus; Zygotic embryos.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300030

A herpes simplex viral vector expressing green fluorescent protein can be used to visualize morphological changes in high-density neuronal culture
Provedor de dados: Electronic Journal of Biotechnology
Autores: Falk,Torsten; Strazdas,Lori A.; Borders,Rebecca S.; Kilani,Ramsey K.; Yool,Andrea J.; Sherman,Scott J.
High-density cultures of mammalian neurons offer a model system for studies of brain development, but the morphological features of individual neurons is difficult to ascertain. We show that a herpes virus vector expressing a bioluminescent protein allows detailed morphometric analyses of living neurons in complex culture environments. Expression of enhanced green fluorescent protein (eGFP) was constitutively driven in neurons using the herpes simplex virus amplicon system. This system allowed us to make novel observations regarding development in high-density cultures from rat hippocampus and cerebellum. After the phase of initial neurite outgrowth, maturing neurons continue to show rapid remodeling of the neurite branches (0.79 ± 0.11 mum/h per neurite;...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000100004

Effect of cryopreservation on the efficiency of exogenous gene, genetic transformation and expression level of Arabidopsis thaliana
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Zhongai; Du,Yaqiong; Wang,Zicheng.
Background: Cryopreservation refers to the storage of a living organism at ultra-low-temperature for long-term preservation of plant germplasm. The effect of cryopreservation on the efficiency of exogenous gene genetic transformation and expression level were studied herein. In this work, transgenic Arabidopsis thaliana were successfully conserved in vitro by cryopreservation methods. Results: The effects of osmotic stress due to cryoprotectants during pretreatment and of storage at -196ºC on the stability, the efficiency of genetic transformation and the expression level of exogenous gene were analyzed in Arabidopsis. The results showed that there had not any significant increasing in the efficiency of genetic transformation after cryopreservation, and...
Tipo: Journal article
Palavras-chave: Arabidopsis thaliana; Cryopreservation; Real-time PCR; Transformation efficiency.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600012

The commercialization of bioinformatics
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jones,Phillip B.C.
Biological research has experienced a paradigm shift from in vivo or in vitro experimentation to in silico experimentation, a development that relies upon bioinformatics. The beginning of bioinformatics stems from the fortuitous timing of the adoption of new DNA sequencing methods and the availability of mini-and bench-top computers, which became the tools to store and to analyze the sequence data. Another fortunate coincidence was the popularization of the Internet, which provided a means to exchange sequence data and sequence analysis software, and the establishment of the Human Genome Project, which stimulated the need for sophisticated data management and analysis tools. Market pull has rapidly stimulated bioinformatics commercialization as...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000200002

Vaccines for finfish aquaculture: What do we need to know to make them work?
Provedor de dados: Electronic Journal of Biotechnology
Autores: Dixon,Brian.
Aquaculture still faces serious economic impacts due to the loss of animals to disease. A conservative estimate of 5% losses due to disease means that the finfish aquaculture industry loses over $1 billion annually on a global scale. One proven way to prevent costly disease outbreaks is to vaccinate fish against common or known pathogens. Current vaccination schemes still result in losses, however, and this may be due in part to vaccine design. Vaccines are currently designed using state of the art knowledge of immune responses, which is based primarily on mammalian studies. Just how applicable is this information to fish immunity and vaccine design, however? This review discusses what is currently known for teleost fish about two key processes that drive...
Tipo: Journal article
Palavras-chave: Antibody; Antigen presentation; Cloning; Cytokine; Immunity; Major histocompatibility complex receptors.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500014

The use of dried spent yeast as a low-cost nitrogen supplement in ethanol fermentation from sweet sorghum juice under very high gravity conditions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sridee,Worawut; Laopaiboon,Lakkana; Jaisil,Prasit; Laopaiboon,Pattana.
Dried spent yeast (DSY) was used as a low-cost nitrogen supplement for ethanol fermentation from sweet sorghum juice under very high gravity (VHG) conditions by Saccharomyces cerevisiae NP 01. The fermentation was carried out at 30ºC in a 5-litre bioreactor. The results showed that DSY promoted ethanol production efficiencies. The ethanol concentration (P), productivity (Qp) and yield (Yp/s) of the sterile juice (total sugar of 280 g l-1) supplemented with 8 g l-1 of DSY were not different from those supplemented with yeast extract and/or peptone at the same amount. The initial yeast cell concentration of 5 x 10(7) cells ml-1 was found to be optimal for scale-up ethanol production. In addition, an increase in sugar concentration in inoculum preparation...
Tipo: Journal article
Palavras-chave: Bioethanol; Dried spent yeast; Scale-up; Sweet sorghum juice; Very high gravity fermentation.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600003

Characterization of novel genic SSR markers in Linum usitatissimum (L.) and their transferability across eleven Linum species
Provedor de dados: Electronic Journal of Biotechnology
Autores: Soto-Cerda,Braulio J; Saavedra,Hector Urbina; Navarro,Cristell Navarro; Ortega,Paula Mora.
Little is known about the evolutionary relationships among Linum species, basically because of the lack of transferable molecular markers. Currently, expressed sequence tags available in public databases provide an opportunity for the rapid and inexpensive development of simple sequence repeat (SSR) markers in wild flax species. In this regard, fifty expressed sequence tag-derived microsatellite markers (EST-SSRs) were evaluated for polymorphism and transferability in 50 Linum usitatissimum cultivars/accessions and 11 Linum species. Among them 23 EST-SSRs were polymorphic in L. usitatissimum, while 2-4 alleles were detected (average 2.26 per locus). The polymorphism information content value ranged from 0.08 to 0.55 (average 0.38). Forty one genic markers...
Tipo: Journal article
Palavras-chave: EST-SSRs; Expressed sequence tag; Flaxseed; Polymorphic loci; Relatives.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200004

Isolation of total RNA from hard bamboo tissue rich in polyphenols and polysaccharides for gene expression studies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rai,Vineeta; Ghosh,Jayadri Sekhar; Dey,Nrisingha.
RNA isolation from hard and woody internodal bamboo (Bambusa balcooa) tissue is very difficult due to the presence of secondary metabolites, polysaccharides, and polyphenolics. These compounds often co-precipitate with isolated RNA and hinder downstream applications. We have developed an efficient, cost effective and reproducible RNA isolation method from hard tissue of bamboo internode. This protocol includes an additional organic solvent refinement steps to remove endogenous phenolic compounds and acidic phenol (pH 4.2) to critically stabilize RNA in extraction buffer. In addition to these, two 2M Lithium chloride washing steps were introduced to eliminate DNA and polysaccharides contamination. The RNA isolated from the present protocol was found to be...
Tipo: Journal article
Palavras-chave: Acid phenol; Bambusa balcooa; Fiber specific genes; Internode; RNA extraction.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500022

Mapping aluminum tolerance loci in cereals: A tool available for crop breeding
Provedor de dados: Electronic Journal of Biotechnology
Autores: Inostroza-Blancheteau,Claudio; Soto,Braulio; Ibáñez,Cristian; Ulloa,Pilar; Aquea,Felipe; Arce-Johnson,Patricio; Reyes-Díaz,Marjorie.
Aluminum (Al) toxicity is the main factor limiting crop productivity in acidic soils around the world. In cereals, this problem reduces crop yields by 30-40%. The use of DNA-based markers linked to phenotypic traits is an interesting alternative approach. Strategies such as molecular marker-assisted selection (MAS) in conjunction with bioinformatics-based tools such as graphical genotypes (GGT) have been important for confirming introgression of genes or genomic regions in cereals but also to reduce the time and cost of identifying them through genetic selection. These biotechnologies also make it possible to identify target genes or quantitative trait loci (QTL) that can be potentially used in similar crops to increase their productivity. This review...
Tipo: Journal article
Palavras-chave: Aluminum tolerance; ALMT1; Cereals; Marker-assisted selection; Organic acid.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400011

A microbial community analysis of the octocoral Eunicea fusca
Provedor de dados: Electronic Journal of Biotechnology
Autores: Duque-Alarcón,Angela; Santiago-Vázquez,Lory Z; Kerr,Russell G.
While there is a significant and growing body of knowledge describing the microbial communities of marine invertebrates such as sponges, there are very few such studies focused on octocorals. The octocoral Eunicea fusca is common on reefs in various regions of the Caribbean and has been the subject of natural product investigations. As part of an effort to describe the microbial community associated with octocorals, a culture-independent analysis of the bacterial community of E. fusca was conducted. Specifically, a 16S rDNA clone library analysis was performed to provide baseline data. A total of 40 bacteria members from 11 groups were found. In general, Proteobacteria were the dominant group with a total of 24 species and &amp;#945;-Proteobacteria...
Tipo: Journal article
Palavras-chave: 16S rDNA; Bacteria; Culture-independent analysis; Eunicea fusca; Microbial community; Octocoral.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500015

Characterization and properties of the biosurfactant produced by Candida lipolytica UCP 0988
Provedor de dados: Electronic Journal of Biotechnology
Autores: Diniz Rufino,Raquel; Moura de Luna,Juliana; de Campos Takaki,Galba Maria; Asfora Sarubbo,Leonie.
Background: Biotechnological processes are costly, especially for the production of biosurfactants. The successful production of a biosurfactant is dependent on the development of processes using low cost raw materials. Considering the importance of the characteristics of a biosurfactant to facilitate its industrial application, the properties of the biosurfactant produced by Candida lipolytica through previously optimized medium have been established. Results: The yeast was grown for 72 h to determine the kinetics of growth and production. The surface tension of the cell-free broth was reduced from 55 to 25 mN/m. The yield of biosurfactant was 8.0 g/l with a CMC of 0.03%. The biosurfactant was characterized as an anionic lipopeptide composed of 50%...
Tipo: Journal article
Palavras-chave: Biosurfactant; Candida lipolytica; Lipopeptide; Surface tension; Toxicity.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100006

Sunflower storage proteins are transported in dense vesicles that contain proteins homologous to the pumpkin vacuolar sorting receptor PV 72
Provedor de dados: Electronic Journal of Biotechnology
Autores: Molina,María Isabel; Otegui,Marisa; Petruccelli,Silvana.
Storage proteins are transported to a special storage compartments in seeds by Golgi dependent or independent pathways depending on the plant species. The aim of this work was to study the sunflower storage protein transport pathway and identified component of the sorting machinery. Immature sunflower seeds were analyzed by subcellular fractionation (using percoll and sucrose gradients) and electron microscopy. The vesicles isolated with percoll, have precursors of 11S globulins, &amp;#945;-TIP, &amp;#948;-TIP, BiP, and two proteins that have homology to the pumpkin vacuolar sorting receptor PV72. Sucrose isolated vesicles have the same composition than percoll ones, except for the lack of BiP and the presence of only one protein that has reactivity with...
Tipo: Journal article
Palavras-chave: Developing sunflower seeds; Storage proteins; Transport pathway; Vacuolar sorting; Vacuolar sorting receptor.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300029

Production and characterization of algae extract from Chlamydomonas reinhardtii
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kightlinger,Weston; Chen,Kai; Pourmir,Azadeh; Crunkleton,Daniel W; Price,Geoffrey L; Johannes,Tyler W.
Background: Algae offer many advantages as biofuel sources including: high growth rates, high lipid content, the ability to grow on non-agricultural land, and the genetic versatility to improve strains rapidly and produce co-products. Research is ongoing to make algae biofuels a more financially attractive energy option; however, it is becoming evident that the economic viability of algae-based fuels may hinge upon high-value co-products. This work evaluated the feasibility of using a co-product, algae extract, as a nutrient source in cell culture media. Results: Algae extract prepared from autolysed Chlamydomonas reinhardtii was found to contain 3.0% protein, 9.2% total carbohydrate, and 3.9% free &amp;#945;-amino acid which is similar to the nutrient...
Tipo: Journal article
Palavras-chave: Algae extract Algae; Chlamydomonas reinhardtii; Microalgae; Culture media.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100003

An approach to the study of the fungal deterioration of a classical art material: Mastic varnish
Provedor de dados: Electronic Journal of Biotechnology
Autores: Romero-Noguera,Julio; López-Miras,María del Mar; Martín-Sánchez,Inés; Ramos-López,José Miguel; Bolívar-Galiano,Fernando.
Mastic, one of the best natural varnishes, is frequently used as protective and finishing layer or as component of oleo-resinous media in paintings, both in the past and currently. However, this resin is affected by complex deterioration processes which can change its characteristics and thus the visual aspect of works of art. The alteration processes caused by radiation have been widely studied, but there is a lack of information on the biodeterioration of this natural product. In this paper, fungi from collections as well as from oil paintings of the Fine Arts Museum of Granada (Spain) were inoculated onto slides covered with mastic. The samples, after an incubation period of 15 days, were analysed by gas chromatography-mass spectrometry (GC-MS) to...
Tipo: Journal article
Palavras-chave: Biodeterioration; Fungi; GC-MS; Mastic.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600001

In vivo assessment of possible probiotic properties of Zymomonas mobilis in a Wistar rat model
Provedor de dados: Electronic Journal of Biotechnology
Autores: Azerêdo,Geíza Alves de; Stamford,Tânia Lúcia Montenegro; Souza,Evandro Leite de; Veras,Flávio Fonseca; Almeida,Edvaldo Rodrigues de; Araújo,Janete Magali de.
In recent years the incorporation of probiotic bacteria into foods has received increasing scientific interest for health promotion and disease prevention. The safety and probiotic properties of Zymomonas mobilis CP4 (UFPEDA-202) was studied in a Wistar rat model fed the 10(9) colony forming units (cfu)/mL-1 of the assayed strain for 30 days. No abnormal clinical signs were noted in the group receiving viable cells of Z. mobilis and water (control) during the period of the experiment. There were no significant difference (p &gt; 0.05) in feed intake and weight gain among mice fed the Z. mobilis in comparison to the control group. No bacteria were found in blood, liver and spleen of any animals. Mice receiving Z. mobilis showed significantly differences (p...
Tipo: Journal article
Palavras-chave: Health benefit; Safety; Zymomonas mobilis.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000200003

Chlorinated biphenyl degradation by wild yeasts pre-cultured in biphasic systems
Provedor de dados: Electronic Journal of Biotechnology
Autores: Romero,M. Cristina; Reinoso,Enso Hugo; Moreno Kiernan,Alejandro; Urrutia,M. Inés.
Environmental biotechnology has developed as an offshoot from sanitary engineering, and only recently the biological component of the ecosystems had been recognized as relevant when bioremediation strategies must be chosen to solve environmental problems. Yeasts were isolated on 2,4-dichlorobiphenyl, 2,3',4- and 2,4',5-trichlorobiphenyl, poorly soluble compounds in water, as carbon sources. Debaryomyces castelli, Debaryomyces maramus and Dipodascus aggregatus composed the mixed culture and represented 72% of the isolates; their degradation potential were studied in biphasic and monophasic systems. The biphasic cultures were obtained with phenol as the organic phase and MSM as the aqueous ones, the monophasic medium only with MSM. Both cultures were...
Tipo: Journal article
Palavras-chave: Biphasic system; Fungal adaptation; Increased solubilities; Transformation rates; Yeasts communities.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300013

Cloning and chloroplast-targeted expression studies of insect-resistant gene with ricin fusion-gene under chloroplast transit peptide in cotton
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kiani,Sarfraz; Ali,Arfan; Bajwa,Kamran Shehzad; Muzaffar,Adnan; Ashraf,Muhammad Aleem; Samiullah,Tahir Rehman; Shahid,Ahmad Ali; Husnain,Tayyab.
Background: Transgenic plants inhabiting single Bt gene are prone to develop insect resistance and this resistance has been reported in case of some important yield-devastating insect larvae of commercial crops, such as cotton and rice. Therefore, it has become essential to adapt new strategies to overcome the problem of insect resistance and these new strategies should be sophisticated enough to target such resistant larvae in broad spectrum. Among these, plants may be transformed with Bt gene tagged with some fusion-protein gene that possesses lectin-binding capability to boost the binding sites for crystal protein gene within insect mid-gut in order to overcome any chances of insect tolerance against Bt toxin. Enhanced chloroplast-targeted Bt gene...
Tipo: Journal article
Palavras-chave: Chloroplast expression; Chloroplast transit peptide; Cotton transformation; Confocal microscopy; Ricin b-chain.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600013

Evaluation of antimicrobial activity and cell viability of Aloe vera sponges
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gontijo,Sávio Morato de Lacerda; Gomes,Alinne Damásia Martins; Gala-García,Alfonso; Sinisterra,Rubén Dario; Cortés,Maria Esperanza.
Background: Aloe vera L., member of the Liliaceae family, has been shown to stimulate cell proliferation and contribute to healing and angiogenesis, has anti-bacterial, anti-fungal and anti-inflammatory activity. In addition, Aloe vera can be used as a support for drug transport. Our objective is to evaluate antimicrobial activity and cytotoxicity of sponges of Aloe vera L. for use as a carrying support of drugs. Results: In this work, sponge of free Aloe vera (AV) loaded with amoxicillin (AMX) or nystatin (NYS) at 1% w/w, were prepared and physico-chemically characterized via X-ray diffraction, Fourier Transform Infrared Spectroscopy and thermal analysis. Antimicrobial potency of AV sponge alone, loaded with AMX or NYS, against strains of Streptococcus...
Tipo: Journal article
Palavras-chave: Amoxicillin; Cytotoxicity; Drug transport; Nystatin.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000100002

Strategy of oxygen transfer coefficient control on the L-erythrulose fermentation by newly isolated Gluconobacter kondonii
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pan,Long; Fang,Ya-kun; Zhou,Pei; Jin,Kui-qi; Gang,Wang; Liu,Yu-peng.
Background: The effect of diverse oxygen transfer coefficient on the L-erythrulose production from meso-erythritol by a newly isolated strain, Gluconobacter kondonii CGMCC8391 was investigated. In order to elucidate the effects of volumetric mass transfer coefficient (K La) on the fermentations, baffled and unbaffled flask cultures, and fed-batch cultures were developed in present work. Results: With the increase of the K La value in the fed-batch culture, L-erythrulose concentration, productivity and yield were significantly improved, while cell growth was not the best in the high K La. Thus, a two-stage oxygen supply control strategy was proposed, aimed at achieving high concentration and high productivity of L-erythrulose. During the first 12 h, Klawas...
Tipo: Journal article
Palavras-chave: K La; Industrial biotechnology; Process control; Production; Tanning agents; Tanning properties; Artificial tanning; Dihydroxypropanone (DHA); Production of L-erythrulose; Meso-erythritol; Biosynthesis of L-erythrulose.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600004

The genetic dissection of quantitative traits in crops
Provedor de dados: Electronic Journal of Biotechnology
Autores: Semagn,Kassa; Bjørnstad,Åsmund; Xu,Yunbi.
Most traits of interest in plant breeding show quantitative inheritance, which complicate the breeding process since phenotypic performances only partially reflects the genetic values of individuals. The genetic variation of a quantitative trait is assumed to be controlled by the collective effects of quantitative trait loci (QTLs), epistasis (interaction between QTLs), the environment, and interaction between QTL and environment. Exploiting molecular markers in breeding involve finding a subset of markers associated with one or more QTLs that regulate the expression of complex traits. Many QTL mapping studies conducted in the last two decades identified QTLs that generally explained a significant proportion of the phenotypic variance, and therefore, gave...
Tipo: Journal article
Palavras-chave: Association mapping; Linkage disequilibrium; Markers assisted selection; Molecular breeding; Molecular markers; Quantitative trait; QTL mapping; QTL analysis.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500016

Effects of 5-aminolevulinic acid (ALA)-containing supernatants from selected Rhodopseudomonas palustris strains on rice growth under NaCl stress, with mediating effects on chlorophyll, photosynthetic electron transport and antioxidative enzymes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Nunkaew,Tomorn; Kantachote,Duangporn; Kanzaki,Hiroshi; Nitoda,Teruhiko; Ritchie,Raymond J.
Background: Rice is globally one of the most important food crops, and NaCl stress is a key factor reducing rice yield. Amelioration of NaCl stress was assessed by determining the growth of rice seedlings treated with culture supernatants containing 5-aminolevulinic acid (ALA) secreted by strains of Rhodopseudomonas palustris (TN114 and PP803) and compared to the effects of synthetic ALA (positive control) and no ALA content (negative control). Results: The relative root growth of rice seedlings was determined under NaCl stress (50 mM NaCl), after 21 d of pretreatment. Pretreatments with 1 &amp;#956;M commercial ALA and 10X diluted culture supernatant of strain TN114 (2.57 &amp;#956;M ALA) gave significantly better growth than 10X diluted PP803 supernatant...
Tipo: Journal article
Palavras-chave: 5-Aminolevulinic acid (ALA); Antioxidative enzymes; Chlorophyll fluorescence; Rhodopseudomonas palustris; Rice; Salinity.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100004

RNA editing in plant mitochondria, cytoplasmic male sterility and plant breeding.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Araya,Alexandre; Zabaleta,Eduardo; Blanc,Valérie; Bégu,Dominique; Hernould,Michel; Mouras,Armand; Litvak,Simon.
RNA editing in plant mitochondria is a post-transcriptional process involving the partial change of C residues into U. These C to U changes lead to the synthesis of proteins with an amino acid sequence different to that predicted from the gene. Proteins produced from edited mRNAs are more similar to those from organisms where this process is absent. This biochemical process involves cytidine deamination. The cytoplasmic male sterility (CMS) phenotype generated by the incompatibility between the nuclear and the mitochondrial genomes is an important agronomical trait which prevents inbreeding and favors hybrid production. The hypothesis that RNA editing leads to functional proteins has been proposed. This hypothesis was tested by constructing transgenic...
Tipo: Journal article
Palavras-chave: Plant mitochondria; RNA editing; Cytidine deamination; Cytoplasmic male sterility (CMS; Fertility restoration.
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000100004

Influence of 2,4-D and BAP on callus growth and the subsequent regeneration of somatic embryos in long-term cultures of Pelargonium x domesticum cv. Madame Layal
Provedor de dados: Electronic Journal of Biotechnology
Autores: Haensch,Klaus-Thomas.
This long-term study demonstrates for the first time that it is possible to propagate embryogenic cultures in pelargoniums and to subsequently initiate the differentiation of embryos using the cultivar Madame Layal (Pelargonium x domesticum). Propagation of callus was only possible with combinations of 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP), which gave rise to embryos from the primary culture stage on. However, the propagation of cells, as well as the differentiation of embryos, was inhibited by a continuous application of these growth regulators. For this reason, a long period on medium lacking growth regulators was necessary before the differentiation of embryos occurred again. The consequences for improving the propagation...
Tipo: Journal article
Palavras-chave: Auxin; Cytokinin; Propagation; Somatic embryogenesis.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100007

Prediction of xylanase optimal temperature by support vector regression
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Guangya; Ge,Huihua.
Background: Support vector machine (SVM), a novel powerful machine learning technology, was used to develop the non-linear quantitative structure-property relationship (QSPR) model of the G/11 xylanase based on the amino acid composition. The uniform design (UD) method was applied to optimize the running parameters of SVM for the first time. Results: Results showed that the predicted optimum temperature of leave-one-out (LOO) cross-validation fitted the experimental optimum temperature very well, when the running parameter C, &amp;#958;, and &amp;#947; was 50, 0.001 and 1.5, respectively. The average root-mean-square errors (RMSE) of the LOO cross-validation were 9.53ºC, while the RMSE of the back propagation neural network (BPNN), was 11.55ºC. The...
Tipo: Journal article
Palavras-chave: Amino acid composition; Optimum temperature; Support vector machine; Uniform design; Xylanase.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000100007

Identification and genetic diversity analysis of Memecylon species using ISSR, RAPD and Gene-Based DNA barcoding tools
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tumkur Ramasetty,Bharathi; Naik Bajpe,Shrisha; Kigga Kadappa,Sampath Kumara; Kumar Saini,Ramesh; Nittur Basavaraju,Shashibhushan; Kukkundoor Ramachandra,Kini; Harishchandra Sripathy,Prakash.
Background: Memecylon species are commonly used in Indian ethnomedical practices. The accurate identification is vital to enhance the drug's efficacy and biosafety. In the present study, PCR based techniques like RAPD, ISSR and DNA barcoding regions, such as 5s, psbA-trnH, rpoC1, ndh and atpF-atpH, were used to authenticate and analyze the diversity of five Memecylon species collected from Western Ghats of India. Results: Phylogenetic analysis clearly distinguished Memecylon malabaricum from Memecylon wightii and Memecylon umbellatum from Memecylon edule and clades formed are in accordance with morphological keys. In the RAPD and ISSR analyses, 27 accessions representing five Memecylon species were distinctly separated into three different clades. M....
Tipo: Journal article
Palavras-chave: AtpF-atpH; Memecylon species; Ndh; PsbA-trnH; RpoC1; 5s; PCR based techniques; Molecular phylogenetic analysis; Molecular phylogenesis; DNA markers.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600001

A comparative proteomic study of white and black glutinous rice leaves
Provedor de dados: Electronic Journal of Biotechnology
Autores: Phonsakhan,Wipada; Kong-Ngern,Kanlaya.
Background Black glutinous rice contains remarkable levels of anthocyanins, which possess anti-oxidative properties and thus have health benefits. The accumulation of anthocyanins in grains of thirty black glutinous rice varieties was measured, and the results revealed that the accumulated anthocyanin content ranged from 0.262 to 2.539 mg/g. Black glutinous rice Br no. 19 was selected, and its leaf protein expression profile was compared with that of white glutinous rice RD 6 using 2D-PAGE, and the protein spots were then directly analyzed after proteolysis by LC-MS/MS. Results The proteins from the leaves of the two rice varieties were separated using 2D-PAGE and silver stained, and the spots were analyzed using Image Master 2D Platinum version 5...
Tipo: Journal article
Palavras-chave: 2D-PAGE; Anthocyanin; LC-MS/MS; Oryza sativa L; Proteomics.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100006

Physiological-enzymatic characteristics and inoculation of mycelial strains of Descolea antarctica Sing. in Nothofagus seedlings
Provedor de dados: Electronic Journal of Biotechnology
Autores: Valenzuela,Eduardo; Hipp,Joseline; Alonso,Claudia; Godoy,Roberto; Alberdi,Miren; Alvarez,Maricel; Saavedra,Isabel.
At present, reforestation has focused on native forests with anthropogenic intervention and eroded soils. There is interest in producing Nothofagus seedlings which can overcome adverse conditions encountered on reforestation sites. It is necessary to find new fungi that can be utilized as mycorrhizal inoculants and that enable the seedlings to increase their tolerance to adverse conditions. Two ectomycorrhizal strains of the fungus Descolea antarctica (D1 and D2) were cultured at different temperatures, pH levels and the activities of amylases, cellulases, and phosphatases were determined. In greenhouse and nursery trials, the growth responses of inoculated Nothofagus obliqua seedlings were evaluated. D1 and D2 exhibited the highest growth rates at 23ºC....
Tipo: Journal article
Palavras-chave: Cellulose; Ectomycorrhizal fungi; Nothofagus; PH; Phosphatase; Temperature.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200012

Genetic differentiation between Cinta Senese and commercial pig breeds using microsatellite
Provedor de dados: Electronic Journal of Biotechnology
Autores: Scali,Monica; Vignani,Rita; Bigliazzi,Jacopo; Paolucci,Elisa; Bernini,Andrea; Spiga,Ottavia; Niccolai,Neri; Cresti,Mauro.
Background: Cinta Senese (CS) is an autochthonous Tuscan breed, which risked extinction since the ‘60s. Results: Monitoring the genetic variability of the actual population by use of DNA molecular markers is essential to address a correct breeding policy, finalized to obtain the race preservation and its fitness in the future. 17 SSRs autosomal markers and 1 associated to the X chromosome were used to genotype 86 individuals belonging to the CS and 12 belonging to two main white races Landrace (L), Large White (LW) and crosses between LW and L and L and CS widespread in Tuscany and used in the recent past to obtain hybrids with the CS. Conclusions: A dendrogram of similarity measures the relative genetic distance between individuals in the population. Data...
Tipo: Journal article
Palavras-chave: Cinta Senese; Genetic diversity; Genotyping; Microsatellites; Sus scrofa.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000200001

Recombinant human granulocyte-macrophage colony-stimulating factor: effect of glycosylation on pharmacokinetic parameters
Provedor de dados: Electronic Journal of Biotechnology
Autores: Marini,Guillermo; Forno,Guillermina; Kratje,Ricardo; Etcheverrigaray,Marina.
The pharmacokinetic behaviour of the non-glycosylated, bacterially-derived recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) and the glycosylated mammalian product was studied after intra and extra vascular administration of a single dose in rodents. Each route of administration gave a different rhGM-CSF concentration-time profile. After extra vascular administration of equivalent doses, a higher peak concentration and faster elimination were observed in the group treated with the E. coli-derived cytokine. The faster elimination resulted in a return to pre-treatment plasma levels after 12 hrs, versus 48 hrs following the administration of glycosylated rhGM-CSF. After intravascular administration, clearance of rhGM-CSF was...
Tipo: Journal article
Palavras-chave: Glycosylation; Pharmacokinetic parameters; RhGM-CSF.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200011

Elimination of TSWV from Impatiens hawkerii Bull. and regeneration of virus-free plant
Provedor de dados: Electronic Journal of Biotechnology
Autores: Milosevic,Snezana; Subotic,Angelina; Bulajic,Aleksandra; Djekic,Ivana; Jevremovic,Sladjana; Vucurovic,Ana; Krstic,Branka.
The possibility for obtaining virus free plants from Impatiens hawkerii Bull. shoots infected with Tomato spotted wilt virus (TSWV) through meristem-tip culture was examined. TSWV presence in I. hawkerii plants was detected by DAS-ELISA and RT-PCR and identification of the virus was confirmed by sequencing one of the chosen isolate (GenBank Accesion CQ132190). Meristem-tip explants (0.3-1.5 mm) from virus-infected shoots are cultured on MS media supplemented with different concentrations of the cytokinins, CPPU or TDZ (0.01-1.0 µM), respectively. Using this system, a large number of in vitro shoots could be produced from a single explant. Also, cytokinins showed a stimulatory effect on the length, fresh and dry weights of the newly formed shoots. Plant...
Tipo: Journal article
Palavras-chave: Meristem culture; New Guinea Impatiens; Tomato spotted wilt virus; Virus- free plants.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100003

Variety discrimination of Tigridia pavonia (L.f.) DC. assesed by different length RAPD primers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Piña-Escutia,José Luis; Vázquez-García,Luis Miguel; Arzate-Fernández,Amaury Martín.
Tigridia pavonia (L.f.) DC. is one of the important phytogenetic resources of México. This species is used as ornamental, food and medicinal purposes. Despite its ornamental and economic potential, there is little information about the genetic variability. In this study, randomly amplified polymorphic DNA (RAPD) primers of 10, 15 and 20 bases were used to assess the level of genetic variation among nine botanical varieties of Tigridia pavoniacollected in three localities within State of México. The total number fragments, polymorphic fragments, percentage of polymorphism and resolving power were greater for 15 base (55, 52, 94.5 and 5, respectively) and 20 base (47, 45, 95.7 and 3.8, respectively), in comparison with those obtained from 10 base primers...
Tipo: Journal article
Palavras-chave: Genetic resources; RAPD; Tigridia pavonia; Variety discrimination.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400010

Recent developments in biotech industry outside of the USA and Western Europe: Report from BIO 2005
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bourinbaiar,Aldar S.
The BIO 2005 international convention is the largest gathering of the biotech industry in the world. This year it was held on June 19-22 inside the behemoth Convention Center in downtown Philadelphia, bringing together 18,730 executives, investors, consultants, lawyers, politicians, scientists, and dreamers from 56 countries. More than 500 media representatives covered the event. Biotechnology research and findings presented by countries outside the USA and Western Europe has begun to make a significant impact on these annual BIO gatherings. The achievements of some of these countries are briefly reviewed.
Tipo: Journal article
Palavras-chave: Africa; Asia; Bioindustry; Biotech; Biodefense; Eastern Europe; Latin America; Pacific; Russia.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200002

Poly (l-lactide acid) improves complete nano-hydroxyapatite bone scaffolds through the microstructure rearrangement
Provedor de dados: Electronic Journal of Biotechnology
Autores: Shuai,Cijun; Nie,Yi; Gao,Chengde; Lu,Haibo; Hu,Huanlong; Wen,Xuejun; Peng,Shuping.
Cracks often occur when nano-hydroxyapatite bone scaffolds are fabricated with selective laser sintering, which affect the performance of scaffolds. In this study, a small amount of poly (l-lactide acid) (PLLA) was added into nano-hydroxyapatite (nano-HAP) powder by mechanical blending in order to improve the sintering properties. The nano-HAP powder combined with 1wt % PLLA was sintered under different laser power (5W, 7.5W, 10W, 12.5W, 15W and 20W). The fabricated scaffolds were characterized using Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and Micro Hardness Tester. The results showed that nano-HAP particles grew up quickly with the laser power increasing, and there were many strip-like...
Tipo: Journal article
Palavras-chave: Hardness; Microstructure; Nano-hydroxyapatite; Thermal properties.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600004

Molecular cloning, expression and characterization of a serine proteinase from Japanese edible mushroom, Grifola frondosa: solving the structure - function anomaly of a reported aminopeptidase
Provedor de dados: Electronic Journal of Biotechnology
Autores: Islam,Mohammed M.
The N-terminal amino acid sequence of an aminopeptidase from Japanese edible mushroom, Grifola frondosa, was reported to have high similarity with that of a serine proteinase from basidiomycete, Agaricus bisporous (Nishiwaki and Hayashi, 2001). The full-length cDNA and the corresponding genomic DNA of the enzyme were cloned, based on the reported N-terminal amino acid sequence. The predicted open reading frame (ORF) of the cloned cDNA, encoding a product of 379 amino acids, was expressed in E. coli using pET expression vector. The expressed pro-enzyme (40 kDa) underwent autolysis to produce the mature protein (30 kDa) and a pro-peptide (10 kDa). The mature protein and the pro-peptide remained tightly bound to each other and could not be separated by Ni-NTA...
Tipo: Journal article
Palavras-chave: 5'-RACE; CDNA; Genomic DNA; Maitake; Refolding.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400010

New ammonia lyases and amine transaminases: Standardization of production process and preparation of immobilized biocatalysts
Provedor de dados: Electronic Journal of Biotechnology
Autores: Casablancas,Antoni; Cárdenas-Fernández,Max; Álvaro,Gregorio; Benaiges,Maria Dolors; Caminal,Glòria; Mas,Carles de; González,Glòria; López,Carmen; López-Santín,Josep.
Background: New enzymes for biotransformations can be obtained by different approaches including directed mutagenesis and in vitro evolution. These mutants have to be efficiently produced for laboratory research on bioreactions as well as for process development. In the framework of a European ERA-IB project, two different types of enzymes (ammonia lyases and aminotransferases) have been selected as biocatalysts for the synthesis of industrially relevant amines. New mutant enzymes have been obtained: a) aspartases able to recognize &amp;#946;-amino acids; b) &amp;#969;-transaminases with improved activity. The objectives are to find out a common operational strategy applicable to different mutants expressed in E. coli with the same initial genetic...
Tipo: Journal article
Palavras-chave: Amine transaminases; Ammonia lyases; E. coli; Fed-batch; Immobilized biocatalysts.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300004

An economic valuation of a biotechnology R&amp;D project in a developing economy
Provedor de dados: Electronic Journal of Biotechnology
Autores: Erbas,Bahar Celikkol; Memis,Selin Arslanhan.
Background: Biotechnology complements technological developments in main sectors of economies, such as health, energy, and agriculture, and thus contributes to economic development. It provides solutions to the problems that are frequently faced in developing economies, such as resource constraints, lower productivity and environmental concerns. In order to benefit from biotechnology, its associated markets need to develop and function well to support the developments and transactions of intangible assets, such as technology transfers, license agreements and research and development joint ventures. Economic valuation of the intangible assets is necessary for the development and functioning of these markets. It provides better understanding of value...
Tipo: Journal article
Palavras-chave: Biotechnology sector; Developing economies; Real options; R&amp;D project valuation; Turkey.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000300001

Artificial neural network modeling studies to predict the yield of enzymatic synthesis of betulinic acid ester
Provedor de dados: Electronic Journal of Biotechnology
Autores: Moghaddam,Mansour Ghaffari; Ahmad,Faujan Bin H; Basri,Mahiran; Rahman,Mohd Basyaruddin Abdul.
3Î²-O-phthalic ester of betulinic acid was synthesized from reaction of betulinic acid and phthalic anhydride using lipase as biocatalyst. This ester has clinical potential as an anticancer agent. In this study, artificial neural network (ANN) analysis of Candida antarctica lipase (Novozym 435) -catalyzed esterification of betulinic acid with phthalic anhydride was carried out. A multilayer feed-forward neural network trained with an error back-propagation algorithm was incorporated for developing a predictive model. The input parameters of the model are reaction time, reaction temperature, enzyme amount and substrate molar ratio while the percentage isolated yield of ester is the output. Four different training algorithms, belonging to two classes, namely...
Tipo: Journal article
Palavras-chave: Acylation; Artificial neural network; Betulinic acid; Candida antarctica lipase; Enzymatic synthesis; Novozym 435.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300003

Universal protocol for generating 100bp size standard for endless usage
Provedor de dados: Electronic Journal of Biotechnology
Autores: Natarajan,Chandrasekhar; Vijayan,Neetha N; Vaidyan,Linda Koshy; Mathew,Anila; Srinivas,Lekshmy; Banerjee,Moinak.
Developing countries are facing severe bottlenecks in the technological advancement in biotechnology, due to restrictions imposed by patent protected products and protocols. This calls for designing of simple and cost-effective alternatives for the indispensable products like DNA molecular weight markers. We demonstrate a novel, rapid and cost-effective method of making in-house 100bp ladder for routine use. In our method we use a single forward primer and five reverse primers designed on the backbone sequence of a commonly used vector template. These primers are used at a universal annealing temperature to amplify ten DNA fragments of accurate size ranging from 100bp to 1000bp. Our PCR-based method can provide size standards for an endless usage.
Tipo: Journal article
Palavras-chave: 100bp ladder; Cost effective; DNA size standards; Endless usage.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200015

Ethanol mediated enhancement in bacterial transformation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sharma,Arun Dev; Singh,Jaspreet; Gill,Prabhjot Kaur.
In molecular biology, transformation using E. coli as a host plays a key role in synthesizing gene libraries. The present study demonstrated a new ethanol-based method for transformation of plasmid DNA to E. coli. Ethanol at 10% concentration (v/v) showed best results. Further, as compared with traditional CaCl2 method, the transformation rate, using protocol outlined in this study, was very high, suggesting amenable for further applications.
Tipo: Journal article
Palavras-chave: Bacteria; Ethanol; Transformation.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100016

LaNe RAGE: a new tool for genomic DNA flanking sequence determination
Provedor de dados: Electronic Journal of Biotechnology
Autores: Park,Daniel J.
The determination of genomic DNA sequence flanking a known region is often problematic. Existing technologies depend on multiple, efficient enzyme-catalysed preparative processing steps and/or rely on relatively inefficient ‘one-sided' PCR mechanisms. I demonstrate the application of a simple ‘two-sided' PCR-based approach, lariat-dependent nested PCR for rapid amplification of genomic DNA ends (LaNe RAGE), applied to the mouse GAPDH and PGK1 gene flanking sequences. This demonstration offers great promise in applications such as genome walking, transposon mutagenesis mapping and DNA fingerprinting
Tipo: Journal article
Palavras-chave: Cloning; DNA fingerprinting; Genomic DNA walking; PCR; Sequencing; Transposon mutagenesis.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200012

News from the International Council for Science: Strengthening international science for the benefit of society
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cetto,Ana María.
Tipo: Journal article
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200001

A Manuscript Writing Course for Biochemistry Undergraduates and Graduate Students in the Biomedical Sciences
Provedor de dados: Electronic Journal of Biotechnology
Autores: Glew,Robert H.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100001

Relationship between cultivation mode of white rot fungi and their efficiency for olive oil mill wastewaters treatment
Provedor de dados: Electronic Journal of Biotechnology
Autores: Alaoui,Sanae Mdaghri; Merzouki,Mohamed; Penninckx,Michel J; Benlemlih,Mohamed.
Four white rot fungi (WRF) strains, Phanerochaete chrysosporium, Trametes versicolor, Coriolopsis polyzona and Pycnoporus coccineus, were tested for efficiency of treatment of Olive Oil mill wastewaters (OOMW) in relation with their cultivation mode, i.e. under the form of free mycelium, mycelium immobilized in alginate beads and solid state cultivation on Petri dishes. Study of biodegradation of phenolic compounds, chemical oxygen demand (COD) decrease and decolourisation of OOMW have shown that Coriolopsis polyzona and Pycnoporus coccineus degradation performances were apparently only slightly affected by the cell cultivation procedures experienced here. In contrast, Phanerochaete chrysosporium and Trametes versicolor showed respectively marked...
Tipo: Journal article
Palavras-chave: Biotreatment; Cell immobilization; Olive oil mill wastewaters; White rot fungi.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400013

Comparison of haploid and doubled haploid sugar beet clones in their ability to micropropagate and regenerate
Provedor de dados: Electronic Journal of Biotechnology
Autores: Klimek-Chodacka,Magdalena; Baranski,Rafal.
Background: Haploid plant material is considered as recalcitrant to organogenesis, propagation, and maintenance in vitro. However, sugar beet (Beta vulgaris L.) breeders utilizing doubled haploid (DH) technology in their breeding programs indicate that sugar beet haploids may be cultured in vitro as well as diploids. Thus in this paper the in vitro performance of haploid and the doubled haploid sugar beet of various origin was evaluated. The DHs were derived from haploids by diploidization and twelve such haploid and corresponding DH clone pairs were obtained thus the comparison included haploid and DH clones that had identical allelic composition and differed only in their ploidy level. Results: The genotypes differed in shoot morphology and...
Tipo: Journal article
Palavras-chave: Adventitious buds; Axillary shoots; Beta vulgaris; Organogenesis; Ploidy.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000200001

Total RNA quality of lyophilized and cryopreserved dormant grapevine buds
Provedor de dados: Electronic Journal of Biotechnology
Autores: García-Baldenegro,Claudia Vanessa; Vargas-Arispuro,Irasema; Islas-Osuna,María; Rivera-Domínguez,Marisela; Aispuro-Hernández,Emmanuel; Martínez-Téllez,Miguel Ángel.
Background Plant tissues must be preserved in their collection state, especially for genome-wide expression profile studies. Lyophilization is a feasible, affordable tool when fresh tissues cannot be shipped at ultralow temperatures from their origin to the place of analysis. In this study, the total RNA quality of dormant grapevine buds (Vitis vinifera L. cv. ‘Flame Seedless’) of freeze-dried samples stored at room temperature conditions was evaluated and compared to that of cryopreserved (-80°C) grapevine buds. Results Good yield and quality of RNA were obtained from freeze-dried dormant buds stored at room temperature for 0, 3 and 6 weeks after they were lyophilized. Further experiments confirmed that the extracted total RNA could be used for actin and...
Tipo: Journal article
Palavras-chave: Freeze-dried; RNA integrity number; RT-qPCR; Vitis vinifera L; Woody tissue.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200012

Semi-quantitative detection of genetically modified grains based on CaMV 35S promoter amplification
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tozzini,Alejandro C.; Martínez,M. Carolina; Lucca,M. Florencia; Vázquez Rovere,Cecilia; Distéfano,Ana Julia; del Vas,Mariana; Hopp,Esteban.
The detection and exact quantification of the presence of GMOs (genetically modified organisms, also named as living modified organisms, LMOs) grains has become very important in international commercial transactions, especially from countries producing both types of commodities, GMOs and GMO-free. This makes necessary to check every batch previous delivery to the recipient country. Several PCR protocols have been proposed to detect the presence of GMO DNA in a sample due to its sensitivity and independence of environmental and physiological influences. However, most of them are qualitative assays and don’t give a good quantitative estimation of the detected signal. We developed a semi-quantitative method based on the comparison of the mass of the...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000200006

Biological control of Rhizoctonia solani in tomatoes with Trichoderma harzianum mutants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Montealegre,Jaime; Valderrama,Luis; Sánchez,Soledad; Herrera,Rodrigo; Besoain,Ximena; Pérez,Luz María.
Biocontrol of Rhizoctonia solani in tomatoes cultivated under greenhouse and field conditions was analyzed using the Trichoderma harzianum mutants Th650-NG7, Th11A80.1, Th12A40.1, Th12C40.1 and Th12A10.1 and ThF2-1, respectively. Their innocuousness on tomato cultivars 92.95 and Gondola (greenhouse assays), and on cultivar Fortaleza (field assays) was established. Alginate pellets (1.7 g pellets/L soil) containing c.a1 x 10(5) colony forming units (cfu)/g pellet were applied to a soil previously inoculated with R. solani at transplant (greenhouse) or to a naturally infected soil (field). Controls considered parental wild strains, a chemical fungicide and no additions. Th11A 80.1, Th12A10.1 and Th650-NG7 prevented the 100% mortality of tomato plants cv....
Tipo: Journal article
Palavras-chave: Bioantagonism; Field assays; Greenhouse assays; Root rot; Tomato.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000200001

Plant regeneration via indirect somatic embryogenesis and optimisation of genetic transformation in Coffea arabica L. cvs. Caturra and Catuaí
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gatica-Arias,Andrés M; Arrieta-Espinoza,Griselda; Espinoza Esquivel,Ana M.
A protocol for Coffea arabica L. cvs. Caturra and Catuaí plant regeneration via indirect somatic embryogenesis (ISE) was established. Furthermore, a biolistic mediated genetic transformation protocol was optimized for Catuaí callus aggregates. Maximum callus induction was obtained when Caturra (87%) and Catuaí (67%) leaves were cultured on Murashige and Skoog medium with 18.56 µM kinetin and 4.52 µM2,4-dichlorophenoxyacetic acid (2,4-D). Catuaí suspension cultures were established from embryogenic callus using liquid proliferation CP and Sli media and diffused light and darkness. The higher suspension cultures fresh weight was obtained using Erlenmeyer (1425.4 ± 354.9 mg) than Recipient for Automated Temporary Immersion System (RITA®) (518.6 ± 55.1 mg),...
Tipo: Journal article
Palavras-chave: Bioreactor; Coffee; Genetic transformation; Somatic embryogenesis; Suspension cultures.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100010

Extraction of bulk DNA from Thar Desert soils for optimization of PCR-DGGE based microbial community analysis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kumar Gothwal,Raj; Kumar Nigam,Vinod; Mohan,M. Krishna; Sasmal,Dinakar; Ghosh,Purnendu.
A reliable method for characterizing microbial communities on the basis of their differences in the 16S ribosomal RNA (rRNA) gene sequences in the hot arid zone sandy soils has been optimized. A desert plant (Calligonum polygonoides) was chosen to provide the rhizospheric soil samples, collected from three different agro-ecological locations. Total community DNA was efficiently extracted at small-scale level using direct lysis with hot sodium dodecyl sulphate (SDS), glass bead beating and finally subjecting the sandy soil to liquid nitrogen freeze-thaw cycles. To amplify V3 region of bacterial 16S rRNA gene, universal conserved primers were used. Second round polymerase chain reaction (PCR) was attempted to increase product concentration and to minimize...
Tipo: Journal article
Palavras-chave: Arid soils; Microbial community; PCR-DGGE; Rhizosphere; Soil DNA extraction.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300007

High-level soluble expression of the functional peptide derived from the C-terminal domain of the sea cucumber lysozyme and analysis of its antimicrobial activity
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cong,Lina; Liang,Wenjing; Wu,Yao; Li,Cheng; Chang,Yihai; Dong,Liang; Song,Wanlin; Ma,Jun.
Background The sea cucumber lysozyme belongs to the family of invertebrate lysozymes and is thought to be a key defense factor in protecting aquaculture animals against bacterial infection. Recently, evidence was found that the sea cucumber lysozyme exerts broad spectrum antimicrobial action in vitro against Gram-negative and Gram-positive bacteria, and it also has more potent antimicrobial activity independent of its enzymatic activity. To explore the antimicrobial role of this non-enzymatic lysozyme and model its structure to novel antimicrobial peptides, the peptide from the C-terminal amino acid residues 70-146 of the sea cucumber lysozyme in Stichopus japonicus (SjLys-C) was heterologously expressed in Escherichia coli Rosetta(DE3)pLysS. Results The...
Tipo: Journal article
Palavras-chave: Affinity purification; Lysozyme peptide; Molecular modeling; Recombinant protein.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600005

Bioactivity of Scytonema hofmanni (Cyanobacteria) in Lilium alexandrae in vitro propagation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zaccaro,María Cristina; Kato,Adriana; Zulpa,Gloria; Storni,Mónica Magdalena; Steyerthal,Noemí; Lobasso,Karina; Stella,Ana María.
Cyanobacteria produces bioactive compounds including plant growth regulators. Naphthalene acetic acid (NAA), a toxic substance, is a synthetic plant regulator used in micropropagation. The aim of this work was to evaluate morphogenetic and antioxidant effects produced by intra and extracellular substances from Scytonema hofmanni (Cyanobacteria) during the multiplication in vitro of Lilium alexandrae and to compare them to those produced by NAA. Intra and extracellular cyanobacterial products increased a) bulblets production reaching 83% and 78% of NAA effect, respectively; b) the bulblet diameter compared to NAA; and c) the bulblet survival due to the promotion of antioxidant activity measured as catalase, ascorbate peroxidase, and glutathione reductase...
Tipo: Journal article
Palavras-chave: Ascorbate peroxidase; Bioactive substances; Bulb regeneration; Catalase; Cyanobacteria; Glutathione reductase; Lilium alexandrae; Scytonema hofmanni.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300007

Island Communities and Biotechnology
Provedor de dados: Electronic Journal of Biotechnology
Autores: DaSilva,Edgar J.; Taylor,Mary.
In the run-up to the year 2000 and beyond, several island countries, especially in the Caribbean and Pacific regions, are confronted by the challenges and threats of globalization. In response, several island countries are initiating self-reliant strategies aimed at national and regional endogenous development. Amongst these strategies, the potential of biotechnology for economic development and technological growth is being tapped.
Tipo: Journal article
Palavras-chave: Biotechnology; Pacific islands; Caribbean region; MIRCENS.
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000100001

Riverina high school students’ views of biotechnology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cavanagh,Heather; Hood,Jennie; Wilkinson,Jenny.
A survey investigating the knowledge and perception of biotechnology by high school students living in the rural Riverina region of New South Wales, Australia, was undertaken. Data relating to the student’ preferred and trusted information sources was also gathered. This study has demonstrated that at least two-thirds of students had a good knowledge of medical biotechnology issues, however, a significant proportion of the students did have concerns about the use and/or safety of biotechnology. Nearly 90% of the respondents would like further information on biotechnology. In agreement with other surveys, the students reported an apparent lack of trust in articles from the lay press (newspapers, television, radio) and yet still report that these media as...
Tipo: Journal article
Palavras-chave: Biotechnology; Education; Science; Secondary school.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200001

An alternative pathway for plant in vitro regeneration of chinaberry -tree Melia azedarach L. derived from the induction of somatic embryogenesis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sharry,Sandra; Cabrera Ponce,José Luis; Herrera Estrella,Luis; Rangel Cano,Rosa María; Lede,Silvia; Abedini,Walter.
A highly efficient somatic embryogenesis system and subsequent plant regeneration of chinaberry (Melia azedarach L.) was developed. Plants were regenerated from indirect somatic embryogenesis induction. Novel features of this improved protocol, include: a) Embryogenic callus induction with no addition of 2, 4-D in the culture media; b) Somatic embryos differentiation was achieved by using high concentration of cytokinins (BAP 10 mg/L) and adenine; c) 100% conversion of somatic embryos to plants was practically obtained and 100% of plants survived under greenhouse conditions; d) Addition of putrescine improved somatic embryos germination. The amount of somatic embryos produced by the pathway of indirect somatic embryogenesis was 447 per gram of fresh weight...
Tipo: Journal article
Palavras-chave: Callus induction; Clonal forestry; Embryos conversion; Micropropagation; Persian lilac; Somatic embryos.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300003

Induction of in vitro flowering in Capsicum frutescens under the influence of silver nitrate and cobalt chloride and pollen transformation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sharma,Ashwani; Kumar,Vinod; Giridhar,Parvatam; Ravishankar,Gokare Aswathanarayana.
The influence of silver nitrate (AgNO3) and cobalt chloride (CoCl2) on shoot multiplication and in vitro flowering in Capsicum frutescens Mill. was investigated. Exogenous administration of AgNO3 and CoCl2 at a concentration of 30 µM resulted in the maximum tissue response in terms of shoot length and number of shoots after 45 days culturing on MS medium. Both silver nitrate (40 µM) and cobalt chloride (30 µM) influenced in vitro flowering after 25 and 45 days respectively. This is the first report on in vitro flowering in C. frutescens. The study also demonstrated successful transformation of pollen obtained from the in vitro flowers. Since capsicum is highly recalcitrant to in vitro plant regeneration, the results of the study may be highly useful in...
Tipo: Journal article
Palavras-chave: Capsicum frutescens; Cobalt chloride; In vitro flowering; Pollen transformation; Regeneration; Silver nitrate.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200011

Hyper-production of a thermotolerant &amp;#946;-xylosidase by a deoxy-D-glucose and cycloheximide resistant mutant derivative of Kluyveromyces marxianus PPY 125
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rajoka,Muhammad Ibrahim; Khan,Sana.
Production of &amp;#946;-xylosidaseby a cycloheximide and 2-deoxy-D-glucose-resistant mutant of Kluyveromyces marxianus PPY125 was studied when cultured on growth media containing galactose, glucose, xylose, cellobiose, sucrose and lactose as carbon sources. Xylose, cellobiose, lactose and sucrose were the key substrates. Both K. marxianus PPY125 and its mutant (M 125) supported maximum &amp;#946;-xylosidase specific product yield (Y P/X) following growth on xylose. Basal level of activity was observed in non-induced cultures grown on glucose. The mutant produced 1.5 to 2-fold more &amp;#946;-xylosidase than that produced by the wild cells. Synthesis of &amp;#946;-xylosidase was regulated by an induction mechanism in both wild and mutant cells. Addition of...
Tipo: Journal article
Palavras-chave: Enthalpy; Entropy; Enzyme kinetics; Fermentation; Induction; Thermodynamics.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200007

Genetic transformation studies and scale up of hairy root culture of Glycyrrhiza glabra in bioreactor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mehrotra,Shakti; Kumar Kukreja,Arun; Singh Khanuja,Suman Preet; Nath Mishra,Bhartendu.
The study was undertaken to induce hairy roots in Glycyrrhiza glabra in leaf explants and to optimize the nutritional requirement for its growth kinetics at shake flask and bioreactor level. Pathogenecity of Agrobacterium depends upon transformation ability of strain and age, type, and physiological state of explants. Agrobacterium rhizogenes strain K599 was used to infect leaf explants of G. glabra. Explants of different age groups were obtained from 2 to 5 weeks old in vitro grown cultures. Bacterial strain K599 could induce hairy roots in 3 and 4 weeks old leaf explants cultured on B5, MS, NB and WP basal semi-solid medium. Leaf explants of 2 and 5 weeks old culture were not responsive to bacterial infection in terms of hairy root induction. Maximum...
Tipo: Journal article
Palavras-chave: Agrobacterium; Bioreactor; Glycyrrhiza; Scale-up; Transformed roots.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200009

Anti-peptide antibodies: A tool for detecting IL-8 in salmonids
Provedor de dados: Electronic Journal of Biotechnology
Autores: Santana,Paula; Palacios,Claudia; Narváez,Edgar; Guzmán,Fanny; Gallardo,José A; Mercado,Luis.
Background: Interleukin 8 is a chemokine that is produced by several types of cells, like macrophages and has chemotactic activity in particular on neutrophils, playing a key role during the inflammatory process. It has been demonstrated at the molecular level that this molecule is present and conserved in several vertebrate groups, pointing its importance. Analysis of the amino acid sequence of IL-8, projected from cDNA of Salmo salar, presents homology with the sequences of mammals, poultry and lamprey, indicating the presence of a homologous molecule in higher fish. However, there is no information at protein level, which allows characterizing the regulatory role of this molecule during the immune response in fish. Results: In this work, we designed and...
Tipo: Journal article
Palavras-chave: Anti-IL-8; Fish antibodies; Fish chemokine; Rainbow trout; Synthetic peptide epitope.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500020

Operation of a slow rate anaerobic digester treating municipal secondary sludge
Provedor de dados: Electronic Journal of Biotechnology
Autores: Telles Benatti,Cláudia; Granhen Tavares,Célia Regina; Dias Filho,Benedito Prado; Ribeiro Moitinho,Maria da Luz.
This study was designed to evaluate the performance of a slow rate anaerobic digester in treating secondary sewage sludge received from one local municipal wastewater treatment plant. The digester was fed by secondary sewage sludge without any previous thickening. A series of three independent batch experiments was investigated at an operation time of 60 days. The total solids (TS) in the influent sludge contained a percentage of organic matter of 59, 63 and 54%, a concentration of volatile suspended solids (VSS) of 23.7, 29.2 and 27.8 g L-1 and a chemical oxygen demand (COD) of 51.8, 32.9 and 65.7 g L-1 for the three experiments, respectively. The operation of anaerobic digestion was stable, with no noticeable scum or foaming problems. The COD reduction...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300005

The ICY1 gene from Saccharomyces cerevisiae affects nitrogen consumption during alcoholic fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Martínez,Claudio; Contreras,Angela; Aguilera,Omayra; Ganga,Angelica; García,Veronica.
Background Saccharomyces cerevisiae is the main microorganism responsible for alcoholic fermentation. In this process, the consumption of nitrogen is of great importance since it is found in limiting quantities and its deficiency produces sluggish and/or stuck fermentations generating large economic losses in the wine-making industry. In a previous work we compared the transcriptional profiles between genetically related strains with differences in nitrogen consumption, detecting genes with differential expression that could be associated to the differences in the levels of nitrogen consumed. One of the genes identified was ICY1. With the aim of confirming this observation, in the present work we evaluated the consumption of ammonium during the...
Tipo: Journal article
Palavras-chave: Enological traits; Gene expression; Wine fermentation; Wine yeast.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000400002

Optimization of medium composition for transglutaminase production by a Brazilian soil Streptomyces sp.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Macedo,Juliana Alves; Sette,Lara Durães; Sato,Hélia Harumi.
Finding a new microbial source of transglutaminase (MTGase) and the study of the medium composition for MTGase production were the goals of this work. A total of 200 actinomycete-like strains were isolated from Brazilian soil samples and two of them named T10b and P20 were selected based on their ability to produce 0.15 U.mL-1 and 0.25 U.mL-1 of MTGase, respectively. Strain P20 was chosen to continue the study and was identified as Streptomyces sp. In order to optimize the MTGase activity, modifications of the usual media composition described for enzyme production were tested. The strategy adopted was: (1) screening experiment for the best carbon and nitrogen sources; (2) fractional factorial design (FFD) to elucidate the key ingredients in the media (the...
Tipo: Journal article
Palavras-chave: Central composite design; Fractional factorial design; Medium optimization; Microbial transglutaminase; Streptomyces sp. P20.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400014

Sugar cane bagasse as feedstock for second generation ethanol production: Part II: Hemicellulose hydrolysate fermentability
Provedor de dados: Electronic Journal of Biotechnology
Autores: Betancur,Gabriel J. Vargas; Pereira Jr,Nei.
Sugar cane bagasse is produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a potential source for second-generation ethanol production; however a pretreatment stage is essential, which aims at removing the hemicellulose component by disorganizing the lignocellulosic complex. In this work sugar cane bagasse was pretreated by diluted acid hydrolysis resulting in xylose-rich hydrolysates, which could be fermented to ethanol by a strain of the yeast Pichia stipitis. Statistical approach was used to investigate the effects of factors associated with the diluted acid hydrolysis process (acid concentration, solid:liquid ratio and time of exposure) on the fermentability of different hydrolysates. The statistical...
Tipo: Journal article
Palavras-chave: Bioethanol; Pichia stipitis; Xylose fermentation.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500014

A new low molecular mass alkaline cyclodextrin glucanotransferase from Amphibacillus sp. NRC-WN isolated from an Egyptian soda lake
Provedor de dados: Electronic Journal of Biotechnology
Autores: Al-Sharawi,Samar Z.R.; Ibrahim,Abdelnasser S.S.; El-Shatoury,Einas H; Gebreel,Hassan M; Eldiwany,Ahmad.
Background: Cyclodextrin glucanotransferase (CGTase) is one of the most industrially important enzymes used in the commercial production of cyclodextrins (CDs). Alkaliphilic bacteria have attracted much interest in the last few decades because of their ability to produce extracellular enzymes that are active and stable at high pH values. Here, we report the isolation of a new CGTase from alkaliphilic bacteria collected from Egyptian soda lakes and describe the purification and biochemical characterization of this CGTase. Results: Screening for CGTase-producing alkaliphilic bacteria from sediment and water samples collected from Egyptian soda lakes located in the Wadi Natrun valley resulted in the isolation of a potent CGTase-producing alkaliphilic...
Tipo: Journal article
Palavras-chave: Amphibacillus sp; Cyclodextrin glycosyltransferase; Cyclodextrins; Wadi Natrun soda lakes.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600003

STABILITY OF BIOCATALYSTS
Provedor de dados: Electronic Journal of Biotechnology
Biocatalysts are inherently labile; therefore their operational stability is of paramount importance for any bioprocess. The problem of biocatalyst stability has been tackled from different perspectives, which are reviewed in the present paper. Inherently stable biocatalysts are well appreciated and a systematic effort is being done in the search of new organisms that harbor them. The potential of extremophiles has recently been recognized. Moreover, cloning such termophilic genes into more suitable mesophilic hosts is now at hand to produce stable biocatalysts. Another approach is to use site-directed mutagenesis to code for more stable proteins. A relevant number of actual industrial biocatalysts are being produced using such genetic and protein...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000100001

Comparison of commercially-available RNA extraction methods for effective bacterial RNA isolation from milk spiked samples
Provedor de dados: Electronic Journal of Biotechnology
Autores: García-Nogales,Paula; Serrano,Alicia; Secchi,Sonia; Gutiérrez,Serafín; Arís,Anna.
Nucleic-acid based methods for bacterial identification are extremely useful in diagnostic applications due to their specificity and sensitivity. However, they require an optimal purification of the target molecules. As part of the development of a new diagnostic method for the detection of bacterial RNA in cow milk, we have compared four commercially available RNA extraction kits for the isolation of bacterial RNA from spiked UHT milk samples. The kits were compared in terms of extraction efficiency and RNA purity using two bacterial species, the Gram negative Escherichia coli and the Gram positive Staphylococcus aureus. Two kits are based in silica-matrix extraction, and the other two in the guanidinium thiocyanate-phenol-chloroform extraction. In our...
Tipo: Journal article
Palavras-chave: Bacteria; Milk; Purification; RNA.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500019

Development of a caspase-3 antibody as a tool for detecting apoptosis in cells from rainbow trout (Oncorhynchus mykiss)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rojas,Verónica; Guzmán,Fanny; Valenzuela,Cristián; Marshall,Sergio H; Mercado,Luis.
Background: Apoptosis is an active cell death process mediated by caspases activation, in which different extrinsic or intrinsic signalling pathways result in direct activation of effector caspases. Caspase-3 is considered to be the most important of the executioner caspases, which cause the morphological and biochemical changes detected in apoptotic cells. Different bacterial and virus pathogens have developed different strategies to survive inside the host and overcome natural protections, one of them is inducing apoptotic death in infected cells. We have demonstrated previously that Piscirickettsia salmonis activates this process in monocytes/macrophages from salmonid RTS11 cell line both by morphological and caspase detection assays; nevertheless,...
Tipo: Journal article
Palavras-chave: Antibody; Caspase-3; Fish apoptosis; Piscirickettsia salmonis.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500012

Trichoderma aureoviride 7-121, a mutant with enhanced production of lytic enzymes:: its potential use in waste cellulose degradation and/or biocontrol
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zaldívar,Mercedes; Velásquez,Juan Carlos; Contreras,Inés; Pérez,Luz María.
A mutant of the native fungus Trichoderma aureoviride, 7-121, selected for its overproduction of extracellular cellulase and ß-glucosidase (cellobiase) was obtained. In shake flask cultures, production of endoglucanase, filter paper activity and cellobiase increased two to four- fold as compared with the wild type strain. The mutant strain is stable and grows rapidly in liquid as well as in solid culture media. Enzyme yields were best when pH was controlled so that it did not fall bellow pH 3.5. Cellobiase production by this mutant is particularly high (approximately 5 U/ml) as compared to other Trichoderma, strains, which makes it a suitable candidate for waste cellulose degradation. In addition, the mutant strain showed enhanced production of fungal cell...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300011

Bioconversion of apple pomace into a multienzyme bio-feed by two mixed strains of Aspergillus niger in solid state fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhong-Tao,Sun; Lin-Mao,Tian; Cheng,Liu; Jin-Hua,Du.
Apple pomace is a wasted resource produced in large quantities and its deposit has caused serious environmental problems, so it is significance to make the full utilization of the residues. The objectives of this work were to produce multienzyme bio-feed, biodegrade the anti-nutritional factors such as pectin and tannins in apple pomace, and obtain the nutritional enrichment of the fermented substrate. The mixture of apple pomace and cottonseed powder (1:1, w/w), supplemented with 1% (w/w) (NH4)2SO4 and 0.1% (w/w) KH2PO4, was proved to be the optimum medium for the mixed strains of Aspergillus niger M2 and M3 (2:1, w/w). The activities of pectinase, proteinase and cellulase achieved 21168 u/g, 3585 u/g and 1208u/g, and the biodegradation rates of pectin...
Tipo: Journal article
Palavras-chave: Apple pomace; Aspergillus niger; Multienzyme bio-feed; Pectin; Solid state fermentation; Tannins.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000100002

In vitro culture response of barley (Hordeum vulgare) ethylene synthesis mutant MC 169
Provedor de dados: Electronic Journal of Biotechnology
Autores: Biagioli,Carolina; Rios,Raúl; Basso,Alicia; Franzone,Pascual; Prina,Alberto.
Although it is generally accepted that plant in vitro culture response is influenced by the donor genotype, the genetic and molecular bases of this phenomenon are barely known. As a consequence, the optimization of tissue culture protocols is mainly empirically done. Researchers of the IGEAF studied the genetic basis of the in vitro regeneration of various plant species, including the tissue culture response of artificially induced barley mutants. One barley mutant, MC 169, carries a nuclear gene, recently described controlling the root growth in hydroponic cultivation. Under this condition, the roots of MC 169 mutant plants were longer than those of the original wild type line MC 182, a fact that was associated with a reduced ethylene biosynthesis. On the...
Tipo: Journal article
Palavras-chave: Callus induction; Ethylene; Habituated calli; Hydroponic culture; Regeneration.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300019

Assessment of genetic structure in Mexican charolais herds using microsatellite markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sifuentes-Rincón,Ana María; Puentes-Montiel,Herlinda; Parra-Bracamonte,Gaspar Manuel.
Knowledge of livestock genetic diversity is an essential step to respond to commercial demands and reach production objectives in different environments and production systems. The evaluation of animal genetic diversity is achieved by using molecular markers. Microsatellites are the most used markers for studies of this type. Eleven microsatellites were used to evaluate the genetic variation from three populations of Charolais cattle located in northeast Mexico. The studied populations exhibited a high allelic variability with a mean heterozygosity of 0.5. A moderate genetic differentiation between the Charolais populations (F ST = 0.079; P &lt; 0.001) was observed. This suggests subdivisions in Charolais breed established in Mexico, due to genetic...
Tipo: Journal article
Palavras-chave: Charolais; Genetic diversity; Microsatellite.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400002

Infection of Caenorhabditis elegans by Salmonella typhi Ty2
Provedor de dados: Electronic Journal of Biotechnology
Autores: Santander,Javier; Espinoza,Juan Carlos; Campano,María Soledad; Robeson,James.
Several serovars of Salmonella infect and kill the nematode C. elegans. However, here we report that Salmonella typhi Ty2, a representative strain of this human pathogen, readily infects the intestinal lining of C. elegans without significantly affecting its viability. Our observation suggests extending the use of the C. elegans model system for the study of host parasite relationships, to address problems concerning the biology of S. typhi.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000200008

Technical and economic feasibility of gradual concentric chambers reactor for sewage treatment in developing countries
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mendoza,Lourdes; Carballa,Marta; Sitorus,Berlian; Pieters,Jan; Verstraete,Willy.
A major challenge in developing countries concerning domestic wastewaters is to decrease their treatment costs. In the present study, a new cost-effective reactor called gradual concentric chambers (GCC) was designed and evaluated at lab-scale. The effluent quality of the GCC reactor was compared with that of an upflow anaerobic sludge bed (UASB) reactor. Both reactors showed organic matter removal efficiencies of 90%; however, the elimination of nitrogen was higher in the GCC reactor. The amount of biogas recovered in the GCC and the UASB systems was 50% and 75% of the theoretical amount expected, respectively, and both reactors showed a slightly higher methane production when the feed was supplemented with an additive based on vitamins and minerals....
Tipo: Journal article
Palavras-chave: Developing countries; Mesophilic; Nutrients removal; Reactor design; Sewage.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200007

Effect of refrigerated storage on the probiotic survival and sensory properties of milk/carrot juice mix drink
Provedor de dados: Electronic Journal of Biotechnology
Autores: Daneshi,Mohammad; Ehsani,Mohammad Reza; Razavi,Seyed Hadi; Labbafi,Mohsen.
Background: There is a genuine interest in the development of probiotic milk and juice based beverages because they are a good-vehicle to deliver probiotic microorganisms to consumers. For this purpose, the viability and metabolism of four probiotic strains (Lactobacillus acidophilus LA5, Bifidobacterium lactis BB12, L. rhamnosus and L. plantarum) were studied in non-fermented milk and carrot juice mix drink. The drinks were evaluated in 5 days interval for viable cell count, pH, acidity, sedimentation and sensory quality during refrigerated storage at 4 ± 2ºC for up to 20 days. Results: The results showed that all strains had good viability in milk/carrot juice drink (88-98%), but L. acidophilus LA5 seemed more stable than three other strains. The levels...
Tipo: Journal article
Palavras-chave: Carrot juice; Functional beverage; Non-fermented; Probiotic; Viability.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500005

Diversity of marine gliding bacteria in Thailand and their cytotoxicity
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sangnoi,Yutthapong; Srisukchayakul,Pornpoj; Arunpairojana,Vullapa; Kanjana-Opas,Akkharawit.
Eighty-four marine gliding bacteria were isolated from specimens collected in the Gulf of Thailand and the Andaman Sea. All exhibited gliding motility and swarm colonies on cultivation plates and they were purified by subculturing and micromanipulator techniques. Their 16S rRNA genes were amplified by the polymerase chain reaction (PCR) technique. The phylogenetic analysis indicated that the represented isolates can be separated into six different clads (gr 1 - gr 6) within the Cytophaga-Flavobacterium-Bacteriodes (CFB) group. Group 1 formed a remote linear, with only 90% sequence similarity, from Flavobacteriaceae bacterium which indicated a potentially novel taxonomic group. Groups 2 and 3 were identified as the recently proposed Tenacibaculum mesophilum...
Tipo: Journal article
Palavras-chave: Aureispira marina; Aureispira maritime; Fulvivirga kasyanovii; Human cell lines; Rapidithrix thailandica; Tenacibaculum mesophilum.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300003

Biosorption of lead by the brown seaweed Sargassum filipendula - batch and continuous pilot studies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mesquita Vieira,Denise; Augusto da Costa,Antonio Carlos; Assumpção Henriques,Cristiane; Luiz Cardoso,Vicelma; Pessôa de França,Francisca.
The biosorption of lead by the brown alga Sargassum filipendula was studied. pH 4.0 was the optimum value for the biosorption of lead. Isotherms indicated that for solutions containing 0.03 ± 0.001 up to 3.27 ± 0.04 mmol/L of lead, 2.0g/L was the optimum biomass concentration. The Langmuir model was fitted to represent the experimental data, and the kinetics of biosorption presented equilibrium in 30 min. The continuous system operated for 56 hrs presenting a 100% binding of ionic lead, which corresponds to an accumulation of 168 g lead, equivalent to a load of 1.7 mmol ionic lead/g Sargassum filipendula. The results that were obtained in a continuous system showed a gradual saturation of the biomass in the reactors
Tipo: Journal article
Palavras-chave: Biosorption; Biosorption equilibrium continuous system lead Sargassum filipendula.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300004

In Memoriam Rodolfo Ertola (1924-2011)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Merchuck,José.
Tipo: Journal article
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300002

High performance enzymatic synthesis of oleyl oleate using immobilised lipase from Candida antartica
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mat Radzi,Salina; Basri,Mahiran; Bakar Salleh,Abu; Ariff,Arbakariya; Mohammad,Rosfarizan; Abdul Rahman,Mohd. Basyaruddin; Abdul Rahman,Raja Noor Zaliha Raja.
High performance enzymatic synthesis of oleyl oleate, a liquid wax ester was carried out by lipase-catalysed esterification of oleic acid and oleyl alcohol. Various reaction parameters were optimised to obtain high yield of oleyl oleate. The optimum condition to produce oleyl oleate was reaction time; 5 min, organic solvents of log P &amp;ge; 3.5, temperature; 40-50&amp;ordm;C, amount of enzyme; 0.2-0.4 g and molar ratio of oleyl alcohol to oleic acid; 2:1. The operational stability of enzyme was maintained at &gt;90% yield up to 9 cycles. Analysis of the yield of the product showed that at optimum conditions, &gt;95% liquid wax esters were produced
Tipo: Journal article
Palavras-chave: Oleyl oleate; Immobilised lipase; Esterification; Liquid wax ester.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300009

Comparison on the removal of hydrogen sulfide in biotrickling filters inoculated with Thiobacillus thioparus and Acidithiobacillus thiooxidans
Provedor de dados: Electronic Journal of Biotechnology
Autores: Aroca,Germán; Urrutia,Homero; Núñez,Dariela; Oyarzún,Patricio; Arancibia,Alejandra; Guerrero,Karlo.
Emissions of hydrogen sulfide (H2S) by industrial activities is frequent cause of corrosion and unpleasant odours. Treatment of gaseous emissions contaminated with H2S by biotrickling filters inoculated with single cultures of sulfur oxidizer bacteria exhibit several advantages over physicochemical methods, such as shorter adaptation times and higher removal ability. Biofilms of Thiobacillus thioparus and Acidithiobacillus thiooxidans have proved to exhibit high removal capacities, yet no comparative studies between them have been reported. This article reports the efficiency of biotrickling filters inoculated with T. thioparus and A. thiooxidans under similar conditions excepting the pH, that was the optimal for the bacterial growth, for the removal of...
Tipo: Journal article
Palavras-chave: Acidithiobacillus thiooxidans; Biofilm; Biofiltration; Hydrogen sulfide; Thiobacillus thioparus.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400005

Evaluation of diversity among Argentine grapevine (Vitis vinifera L.) varieties using morphological data and AFLP markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Martínez,Liliana; Cavagnaro,Pablo; Masuelli,Ricardo; Rodríguez,José.
Half of the Argentine grapevine growing area is cultivated with local varieties generically called "Criollas". These materials differ in morphology, physiology and enological aptitudes from traditional European varieties. To discriminate among them, we used morphological markers to evaluate the genetic diversity and phenetic relatedness of 9 Criollas, 6 European and 1 American varieties and compared with AFLP markers. Three AFLP primer combinations generated a total of 111 scorable fragments. Dendrograms obtained with morphologic and AFLP markers agreed in clustering the "Criollas" separately from the European and American varieties assayed, except for Muscat d’ Alexandrie and Tempranillo which clustered with Criollas in the case of AFLP. Comparison of...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300009

Isolation and partial purification of a metabolite from a mutant strain of Bacillus sp. with antibiotic activity against plant pathogenic agents
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bernal,Giuliano; Illanes,Andrés; Ciampi,Luigi.
The use of microorganisms for biological purposes has become an effective alternative to control plant pathogens. There are many examples of formulations using bacterial or fungal strains with biocontrol applications. Among them, members of the genus Bacillus are well known antibiotic producers. However, the increased capacity of antibiotic production obtained by direct mutagenesis of wild strains, has seldom been reported in the open literature. This research refers to the mutation of the A47 Bacillus strain, a plant pathogen antagonist, in order to obtain an improved strain with enhanced capacity to synthesize metabolites with antibiotic activity. The mutant strain M40 was obtained using the mutagenic agent acridine orange. The mutant strain showed a...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100008

Characterization of a thermostable extracellular tannase produced under submerged fermentation by Aspergillus ochraceus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gonçalves,Heloísa Bressan; Riul,Alana Jacomini; Quiapim,Andréa Carla; Jorge,João Atílio; Guimarães,Luis Henrique Souza.
Background: Tannases are enzymes that may be used in different industrial sectors as, for example, food and pharmaceutical. They are obtained mainly from microorganisms, as filamentous fungi. However, the diversity of fungi stays poorly explored for tannase production. In this article, Aspergillus ochraceus is presented as a new source of tannase with interesting features for biotechnological applications. Results: Extracellular tannase production was induced when the fungus was cultured in Khanna medium with tannic acid as carbon source. The extracellular tannase was purified 9-fold with 2% recovery and a single band corresponding to 85 kDa was observed in SDS-PAGE. The native apparent molecular mass was estimated as 112 kDa. Optima of temperature and pH...
Tipo: Journal article
Palavras-chave: Aspergillus ochraceus; Gallic acid; Tannase; Tannic acid; Tannin acyl hydrolase.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500004

Cellulase production by thermophilic Bacillus sp: SMIA-2 and its detergent compatibility
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ladeira,Silvania A; Cruz,Erica; Delatorre,Andréia B; Barbosa,João B; Leal Martins,Meire Lelis.
Background This paper reports the production of cellulase by thermophilic Bacillus sp. SMIA-2 using sugarcane bagasse and corn steep liquor as substrates. Some biochemical properties of the enzyme were also assessed for the purposes of exploiting its potential in the detergent industry, as well as other suitable applications. Results Bacillus sp. produced cellulases when cultivated at 50°C in liquid cultures containing sugarcane bagasse and corn steep liquor. Maximum avicelase (0.83 U mL-1) and CMCase (0.29 U mL-1) activities were reached in 120 h and 168 h of culturing time, respectively. The avicelase and CMCase presented an optimum activity at pH of 7.5 and 8.0, respectively. The maximum stability of avicelase and CMCase was observed at a pH range...
Tipo: Journal article
Palavras-chave: Avicelase; Carboxymethylcellulase; Corn steep liquor; Sugarcane bagasse.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200008

Methylation-specific PCR analysis in Col8A1 promoter in Creole cattle carrier of rob(1;29)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Postiglioni,Alicia; García,Cristina B; Rincón,Gonzalo; Arruga,M. Victoria.
Robertsonian translocation (rob(1;29)) is the most frequent structural chromosomal abnormality in cattle. Heterozygous carriers have a normal phenotype but show a 3-5% decrease in fertility. Chromatin decondensation was evaluated similar to the inactive X chromosome when submitted to demethylating agent. Based on this result, and the concept that imprinted genes are essential in embryonic development, we decided to query genes located on BTA1 and BTA29 that could undergo genome imprinting. The collagen typeVIII-Î±1 (Col8A1) acted on extracellular matrix structural proteins. DNA bisulfite conversion and sequentiation methods were used to compare its differential methylation patterns. It was performed on eight Creole cattle DNA blood samples from normal and...
Tipo: Journal article
Palavras-chave: Bisulfite; Collagen; Creole cattle; Cytosines; Methylation.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300013

Behavior of Araujiain, a new cysteine phytoprotease, in organic media with low water content
Provedor de dados: Electronic Journal of Biotechnology
Autores: Quiroga,Evelina; Priolo,Nora; Marchese,José; Barberis,Sonia.
In this paper we studied the effect of different organic solvents (1-octanol, trichloroethylene, ethanol, ethyl acetate, tetrahydrofuran, cyclohexane, propanone, acetonitrile, dichloromethane, chlorobenzene, N,N-dimethylformamide, acetophenone, diethyl ether, methanol, ethylene glycol and toluene) with low and constant water content on substrate preferences, thermostability and stability (caseinolytic activity retention after 4 h) of proteases of Araujia hortorum Fourn. (Asclepiadaceae). The stability of araujiain was high in N,N-dimethylformamide and ethanol at 40&amp;ordm;C, but decreased at higher temperature. Araujiain substrates preferences in buffer Tris-HCl (pH 8), ethylene glycol and N,N-dimethylformamide exhibited different patterns, but the...
Tipo: Journal article
Palavras-chave: Araujia hortorum Fourn; Organic solvents; Plant protease; Substrate preferences; Thermostability.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100004

Chitinase from Enterobacter sp. NRG4: Its purification, characterization and reaction pattern
Provedor de dados: Electronic Journal of Biotechnology
Autores: Dahiya,Neetu; Tewari,Rupinder; Tiwari,Ram P; Singh Hoondal,Gurinder.
Enterobacter sp. NRG4 was shown to excrete chitinase into the culture supernatant when cultivated in medium containing chitin. A 60 kDa extracellular chitinase was purified to homogeneity and characterized. The enzyme hydrolyzed swollen chitin, colloidal chitin, regenerated chitin and glycol chitin but did not hydrolyze chitosan. The chitinase exhibited Km and Vmax values of 1.43 mg ml-1 and 83.33 µM µg-1 h-1 for swollen chitin, 1.41 mg ml-1 and 74.07 µM µg-1 h-1 for colloidal chitin, 1.8 mg ml-1 and 40 µM µg-1 h-1 for regenerated chitin and 2.0 mg ml-1 and 33.33 µM µg-1 h-1 for glycol chitin, respectively. The optimal temperature and pH for activity were 45ºC and pH 5.5, respectively. Mg2+, K+ and Ca2+ stimulated chitinase activity by 13, 16 and 18%,...
Tipo: Journal article
Palavras-chave: Chemical modification; Chitinase; Enterobacter sp. NRG4; Purification; Substrate binding.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200003

Natural carriers in bioremediation: A review
Provedor de dados: Electronic Journal of Biotechnology
Autores: Dzionek,Anna; Wojcieszy&amp;#324;ska,Danuta; Guzik,Urszula.
Bioremediation of contaminated groundwater or soil is currently the cheapest and the least harmful method of removing xenobiotics from the environment. Immobilization of microorganisms capable of degrading specific contaminants significantly promotes bioremediation processes, reduces their costs, and also allows for the multiple use of biocatalysts. Among the developed methods of immobilization, adsorption on the surface is the most common method in bioremediation, due to the simplicity of the procedure and its non-toxicity. The choice of carrier is an essential element for successful bioremediation. It is also important to consider the type of process ( n s tu or ex s tu), type of pollution, and properties of immobilized microorganisms. For these reasons,...
Tipo: Journal article
Palavras-chave: Adsorption; Bioethanol production; Contamination; Heavy metals; Immobilization; Immobilized microorganisms; Natural carriers; Wine alterations; Wood barrels; Xenobiotics.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500008

Database integration with the Web for biologists to share data and information
Provedor de dados: Electronic Journal of Biotechnology
Autores: Xia,Yulu; Stinner,Roland E.; Chu,Ping-Chu.
The Internet has fundamentally changed the way we conduct our business. Even 10 years ago or so, it was not possible to order a book or access a sequence database in another continent using the computer in our office. All these become possible due to the progress in information technology. It is especially important for biologists to realise that information technology has brought us enormous opportunities in sharing our data. In this paper, authors review and introduce the technologies relating to biological data, database, dynamic integration of databases with the World Wide Web (Web hereafter), and data standardisation.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200010

EDITORIAL ELECTRONIC JOURNAL OF BIOTECHNOLOGY ....MOVING FROM SCIENCE TO DEVELOPMENT...
Provedor de dados: Electronic Journal of Biotechnology
Tipo: Journal article
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300001

Letter received on Wednesday 14, August, 2002
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wager,Robert; LaFayette,Peter; Parrott,Wayne.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200002

Genetic diversity associated with agronomic traits using microsatellite markers in Pakistani rice landraces
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pervaiz,Zahida Hassan; Rabbani,M. Ashiq; Khaliq,Ishtiaq; Pearce,Stephen R; Malik,Salman A.
Genetic diversity underlies the improvement of crops by plant breeding. Land races of rice (Oryza sativa L.) can contain some valuable alleles not common in modern germplasm. The aim here was to measure genetic diversity and its effect on agronomic traits among rice land-race genotypes grown in Pakistan. Diversity was measured using thirty-five microsatellite markers and seventy-five genotypes. Among the markers used a total of 142 alleles were detected at 32 polymorphic SSR loci, while three loci were monomorphic in Pakistani rice landraces. The number of alleles identified by each marker ranged from 2 to 13 with a mean of 4.4. Size differences between the smallest and largest alleles varied from 11bp to 71bp. Polymorphism information content ranged from...
Tipo: Journal article
Palavras-chave: Genetic diversity; Landraces; Microsatellite markers; Oryza sativa L.; Pakistan; Rice.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300004

Purification and characterization of an aspartic protease from the Rhizopus oryzae protease extract, Peptidase R
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hsiao,Nai-Wan; Chen,Yeh; Kuan,Yi-Chia; Lee,Yen-Chung; Lee,Shuo-Kang; Chan,Hsin-Hua; Kao,Chao-Hung.
Background Aspartic proteases are a subfamily of endopeptidases that are useful in a variety of applications, especially in the food processing industry. Here we describe a novel aspartic protease that was purified from Peptidase R, a commercial protease preparation derived from Rhizopus oryzae. Results An aspartic protease sourced from Peptidase R was purified to homogeneity by anion exchange chromatography followed by polishing with a hydrophobic interaction chromatography column, resulting in a 3.4-fold increase in specific activity (57.5 × 10³ U/mg) and 58.8% recovery. The estimated molecular weight of the purified enzyme was 39 kDa. The N-terminal sequence of the purified protein exhibited 63-75% identity to rhizopuspepsins from various Rhizopus...
Tipo: Journal article
Palavras-chave: Chromatography; Endopeptidase; Food processing industry; Homogeneity; Rhizopuspepsin.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000200006

Role of PPase-SE in Geotrichum klebahnii, a yeast-like fungus able to solubilize pectin
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rojas,Natalia Lorena; Cavalitto,Sebastián Fernando; Mignone,Carlos Fernando; Hours,Roque Alberto.
Protopectinases (PPases) constitute a heterogeneous group of extracellular enzymes able to release soluble pectin from insoluble protopectin in plant tissues. Geotrichum klebahnii (ATCC 42397) produces PPase-SE with endopolygalacturonase activity. PPase-SE has been used for pectin extraction and maceration of plant tissues. Here, the capacity of G. klebahnii to use different pectins as carbon and energy sources (CES) was studied, in addition to PPase-SE capacity to release pectin from lemon peel. The strain was unable to use pectin from different origins as CES. When G. klebahnii was cultivated with mixtures of different amounts of glucose and citrus pectin as CES, the biomass obtained was proportional to the initial concentration of glucose, which was...
Tipo: Journal article
Palavras-chave: Carbon balance; Enzymatic pectin extraction; Microbial pectin utilization; Pectinases; Synthetic medium.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100012

Soft computing model on genetic diversity and pathotype differentiation of pathogens: A novel approach
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gürüler,Hüseyin; Peker,Musa; Baysal,Ömür.
Background Identifying and validating biomarkers' scores of polymorphic bands are important for studies related to the molecular diversity of pathogens. Although these validations provide more relevant results, the experiments are very complex and time-consuming. Besides rapid identification of plant pathogens causing disease, assessing genetic diversity and pathotype formation using automated soft computing methods are advantageous in terms of following genetic variation of pathogens on plants. In the present study, artificial neural network (ANN) as a soft computing method was applied to classify plant pathogen types and fungicide susceptibilities using the presence/absence of certain sequence markers as predictive features. Results A plant pathogen,...
Tipo: Journal article
Palavras-chave: Computational biology; Genetic diversity; Molecular markers; Plant pathogens; Predictive information; Soft computing.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500004

Analysis of gene expression profiles in response to Sporisorium reilianum f. sp. zeae in maize (Zea mays L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yu,Tao; Wang,Zhenhua; Jin,Xiaochun; Liu,Xianjun; Kan,Shuaishuai.
Background Head smut of maize, which is caused by Sporisorium reilianum f. sp. zeae (Kühn), is a serious disease in maize. In order to reveal the molecular mechanism of the resistance to head smut in maize, a microarray containing ~ 14,850 probes was used to monitor the gene expression profiles between a disease resistant near isogenic line (NIL) and a highly susceptible inbred line after S. reilianum was injected with an artificial inoculation method. Results Levels of expression for 3,532 genes accounting for 23.8% of the total probes changed after inoculation. Gene Ontology analysis revealed that the differentially expressed genes participated in physiological and biochemical pathways. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis...
Tipo: Journal article
Palavras-chave: Differentially expressed genes; Head smut resistance gene; Maize; Microarray.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000500007

Modulation of unsaturated fatty acids content in algae Spirulina platensis and Chlorella minutissima in response to herbicide SAN 9785
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kachroo,Deepa; Singh Jolly,Shaneen M.; Ramamurthy,Viraraghavan.
The accumulation of polyunsaturated fatty acids by algae Spirulina platensis and Chlorella minutissima was studied. Response of these organisms to the substituted pyridazinone, SAN 9785, an inhibitor of the long chain fatty acid desaturase, indicated that fatty acid synthesis and their desaturation were regulated differently in these organisms. While the pool of palmitic acid, the precursor for the unsaturated C18 fatty acids, was stringently maintained in the green alga C. minutissima, in the cyanobacterium S. platensis the level of palmitic acid was liberally maintained in spite of the enhanced accumulation of unsaturated C18 fatty acids.
Tipo: Journal article
Palavras-chave: Chlorella minutissima; Fatty acid desaturation; Polyunsaturated fatty acids; Spirulina platensis; SAN 9785.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400006

Analysis of genetic diversity in the Oryza officinalis complex
Provedor de dados: Electronic Journal of Biotechnology
Autores: Federici,María Teresa; Shcherban,Andrei B.; Capdevielle,Fabián; Francis,Marta; Vaughan,Duncan.
The genetic relationships among 34 accessions of wild rice from Asia, Africa, America and Australia were analysed using RFLP technique. After southern blotting, DNA digestion pattern was hybridised with a highly repetitive DNA sequence of a retrotransposon from a gypsy family of mobile elements. A dendrogram was constructed from RFLP data in which the species clustered according to their genome designation (CC, BB, BBCC and CCDD genomes). Some species did not appear in the same group, for example, O. eichingeri from Africa and Sri Lanka clustered separately from each other. The same situation was observed for the accessions from China of O. officinalis, which cluster together showing a close relationship with O. rhizomatis, and O. eichingeri (both of CC...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200012

Implementation of monitoring for genetically modified rapeseed in Serbia
Provedor de dados: Electronic Journal of Biotechnology
Autores: Nikolic,Zorica; Vujakovic,Milka; Jeromela,Ana Marjanovic; Jovicic,Dusica.
Genetically modified (GMO) rapeseed (Brassica napus) is not grown commercially in European Union, but several lines have been approved for production and use as food and feed. A case-specific monitoring of herbicide-tolerant rapeseed, events RT73, RF3 and T45 was established by Ministry of Agriculture of Republic of Serbia. The objectives of the present study were to introduce methods for detection of herbicide-tolerant GM oilseed rape, investigate occurrence and monitor the presence of GM rapeseed in seed and the feed products, as well as to develop a protocol for quantification. The study was based on 48 samples, rapeseed (33) and feed (15) products, imported from EU countries (Germany, Belgium, France, Czech Republic, Austria) and from domestic market....
Tipo: Journal article
Palavras-chave: Genetically modified organism; Monitoring; Rapeseed.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500017

Consolidated briefing of biochemical ethanol production from lignocellulosic biomass
Provedor de dados: Electronic Journal of Biotechnology
Autores: Spyridon,Achinas; Willem Euverink,Gerrit Jan.
Bioethanol production is one pathway for crude oil reduction and environmental compliance. Bioethanol can be used as fuel with significant characteristics like high octane number, low cetane number and high heat of vaporization. Its main drawbacks are the corrosiveness, low flame luminosity, lower vapor pressure, miscibility with water, and toxicity to ecosystems. One crucial problem with bioethanol fuel is the availability of raw materials. The supply of feedstocks for bioethanol production can vary season to season and depends on geographic locations. Lignocellulosic biomass, such as forest-based woody materials, agricultural residues and municipal waste, is prominent feedstock for bioethanol cause of its high availability and low cost, even though the...
Tipo: Journal article
Palavras-chave: Bioconversion; Bioethanol; Fermentation; Hydrolysis; Renewable fuels.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500009

Enhancement of &amp;#947;-aminobutyric acid in a fermented red seaweed beverage by starter culture Lactobacillus plantarum DW12
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ratanaburee,Anussara; Kantachote,Duangporn; Charernjiratrakul,Wilawan; Penjamras,Pimpimol; Chaiyasut,Chaiyavat.
Lactobacillus plantarum DW12, a gamma-aminobutyric acid (GABA) producing strain, was used as a starter culture to produce a functional fermented red seaweed beverage (FSB). Optimal conditions for producing FSB were established using Central Composite Design by varying the amounts of monosodium glutamate (MSG), sucrose and the initial pH in MRS medium. After a verification test, 1% MSG, 6% sucrose and an initial pH of 6 were selected. Four treatments were tested: traditional formula (A), red seaweed-cane sugar-potable water = 3:1:10, w/w/v, initial pH 6; the traditional formula with a 5% starter culture consisting of 4.1 x 10(9) CFU of DW 12/ml (B); formula A modified by changing the amounts of cane sugar and MSG to 6% and 1%, respectively (C); formula C...
Tipo: Journal article
Palavras-chave: Functional fermented plant beverage; Î³-aminobutyric acid; Lactobacillus plantarum; Monosodium glutamate; Red seaweed; Response surface methodology.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300001

Effects of fermentation substrates and conservation methods on the viability and antimicrobial activity of Weissella confusa and its metabolites
Provedor de dados: Electronic Journal of Biotechnology
Autores: Serna-Cock,Liliana; Enríquez-Valencia,Cruz E; Jiménez-Obando,Eliana M; Campos-Gaona,Rómulo.
Lactic acid bacteria produce metabolites with antagonistic activity against other bacteria. However, growth conditions and conservation methods may reduce the viability and antimicrobial activity of lactic acid bacteria. This study evaluated the effects of fermentation substrate, lyophilization (freeze-drying) and refrigeration on the viability and antimicrobial activity of Weissella confusa strain and its metabolites against pathogens responsible for bovine mastitis. W. confusa strain was grown in MRS broth and milk supplemented with yeast extract and glucose (MYEG). The collected fractions were preserved by lyophilization or under refrigeration at 4ºC. Every seven days, the viability of W. confusa strain and the stability of its metabolites were...
Tipo: Journal article
Palavras-chave: Conservation; Inhibition; Lactic acid bacteria; Lyophilization.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000300006

Equilibrium sorption isotherm studies of Cd(II), Pb(II) and Zn(II) ions detoxification from waste water using unmodified and EDTA-modified maize husk
Provedor de dados: Electronic Journal of Biotechnology
Autores: Igwe,Jude C; Abia,Augustin A.
The mobilization of heavy metals in the environment due to industrial activities is of serious concern due to the toxicity of these metals in humans and other forms of life. The equilibrium adsorption isotherms of Cd(II), Pb(II) and Zn(II) ions, detoxification from waste water using unmodified and EDTA-modified maize husk have been studied. Maize husk was found to be an excellent adsorbent for the removal of these metal ions. The amount of these metal ions adsorbed increased as the initial concentration increased. Also, EDTA-modification enhanced the adsorption capacity of maize husk due to the chelating ability of ethylenediamine tetra acetic acid (EDTA). Among the three adsorption isotherms tested, Dubinin-Radushkevich isotherm gave the best fit with R²...
Tipo: Journal article
Palavras-chave: Adsorption isotherm; EDTA; Heavy metals; Maize husk; Waste water.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400007

Xylella fastidiosa: An in vivo system to study possible survival strategies within citrus xylem vessels based on global gene expression analysis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Federici,María Teresa; Marcondes,Jackson A; Picchi,Simone Cristina; Stuchi,Eduardo S; Fadel,André Luiz; Laia,Marcelo L; Lemos,Manoel Victor F; Lemos,Eliana Gertrudes Macedo.
Xylella fastidiosa inhabits the plant xylem, a nutrient-poor environment, so that mechanisms to sense and respond to adverse environmental conditions are extremely important for bacterial survival in the plant host. Although the complete genome sequences of different Xylella strains have been determined, little is known about stress responses and gene regulation in these organisms. In this work, a DNA microarray was constructed containing 2,600 ORFs identified in the genome sequencing project of Xylella fastidiosa 9a5c strain, and used to check global gene expression differences in the bacteria when it is infecting a symptomatic and a tolerant citrus tree. Different patterns of expression were found in each variety, suggesting that bacteria are responding...
Tipo: Journal article
Palavras-chave: Citrus; Microarray; Xylella fastidiosa.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000300004

An inertizing and cooling process for grapes cryomaceration
Provedor de dados: Electronic Journal of Biotechnology
Autores: Carillo,Maria; Formato,Andrea; Fabiani,Andrea; Scaglione,Giampiero; Pucillo,Giovanni Pio.
Background: With this research an inertizing and cooling process for grapes cryomaceration has been set up. The process in question has been performed by an innovative plant that cooled the grapes rapidly in about 8 sec until they reached the set cryo-maceration temperature, using direct injection of liquid CO2. It works with a grape flow of approximately 2-3 tons/h, with a maximum thermal gradient of 20 K between the grape inlet and outlet temperature. For this plant a vibrating device was set up that allowed that only one grape cluster layer to be formed on the ribbon conveyor after the grapes had been put into the feedbox. A numerical model was set up for the cooling tunnel, and numerical simulations were performed to investigate the operative...
Tipo: Journal article
Palavras-chave: Cryogenic liquid CO2; Cryomaceration process; Inertizing process.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600008

Intramyocardial gene transfer of vascular endothelial growth factor 121 improves myocardial perfusion and function in the ischemic porcine heart
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ojalvo,Ariana G; Seralena,Alina; Vispo,Nelson S; Silva,Ricardo; Gonzalez,Noel; Guevara,Luis; Batista,Juan F; Montequin,Jose F.; Chaos,Nicolas; González,Rafael; Reima,Camilo; Peña,Yamile; Coca,Marcos; Perera,Alejandro; Vazquez,Raysa; Puchades,Yaquelin; Garcia-Osuna,Tamara; Dominguez,Heberto; Reyes,Jose L.; Ali,Alfonso; Herrera,Luis.
Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen that is angiogenic in vitro and in vivo. Several studies report on gene transfer of VEGF121 to promote angiogenesis in the ischemic myocardium of animals and patients. We hypothesized that intramyocardial administration of naked plasmid DNA encoding VEGF121 could improve myocardial perfusion and function in a porcine model of myocardial ischemia. Yorkshire swine underwent thoracotomy and placement of an ameroid constrictor on the circumflex coronary artery. Four weeks later, pVEGF121 plasmid was administered into the ischemic myocardium. Four weeks after gene transfer, SPECT imaging demonstrated significant reduction in the ischemic area in pVEGF121-treated animals compared...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300008

Production of Rhodotorula glutinis: a yeast that secretes alpha-L-arabinofuranosidase
Provedor de dados: Electronic Journal of Biotechnology
Autores: Martínez,Claudio; Gertosio,Cecilia; Labbe,Angelica; Pérez,Rafael; Ganga,Maria Angélica.
Rhodotorula glutinis is a yeast that secretes the enzyme alpha-L-arabinofuranosidase (E.C. 3.2.1.55) into the culture medium and thus has an interesting biotechnological potential. To determine improved culture conditions of this organism, different factors of the culture media were evaluated such as the use of peptone as nitrogen source, salts composition, pH and growth temperature. Likewise, beet molasses and beet cosette were tested as industrial carbon sources to induce the production of the enzyme and how they influence the yeast growth. Based on these studies a culture medium is proposed for growth of this yeast in a continuous system. By assaying different dilution rates an average specific activity for the enzyme of 82.4 U/mg of protein was obtained.
Tipo: Journal article
Palavras-chave: Alpha-L-arabinofuranosidase yeast; Enzymes; Wine.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400009

Gene Discovery, Ownership and Access for Developing Countries in the Era of Molecular Genetics
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mansur,Levi.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100006

Group III PLA2 from the scorpion, Mesobuthus tamulus: cloning and recombinant expression in E. coli
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hariprasad,Gururao; Saravanan,Kolandaivelu; Singh,Sundararajan Baskar; Das,Utpal; Sharma,Sujata; Kaur,Punit; Singh,Tej Pal; Srinivasan,Alagiri.
Phospholipases A2 (PLA2) are enzymes that specifically hydrolyze the sn-2 fatty acid acyl bond of phospholipids, producing a free fatty acid and a lyso-phospholipid. We report the cloning and expression of a secretory phospholipase A2 (sPLA2) from Mesobuthus tamulus, Indian red scorpion. The nucleotide sequence codes for a 167 residue enzyme. The open reading frame codes for a 31 amino acid signal peptide followed by a mature portion of the protein. The primary structure shows the calcium binding motif, catalytic residues, 8 highly-conserved cysteines and C-terminal extension which classify it as a group III PLA2. The entire transcript was expressed in Escherichia coli and was purified by metal affinity chromatography under denaturing conditions. The...
Tipo: Journal article
Palavras-chave: Group III phospholipase A2; Mesobuthus tamulus; Recombinant expression.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300006

Detecting adventitious transgenic events in a maize center of diversity
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gamarra,Luis Fernando Rimachi; Delgado,Jorge Alcántara; Villasante,Yeny Aquino; Ortiz,Rodomiro.
Background: The genetic diversity of maize in Peru includes several landraces (within race clusters) and modern open pollinated and hybrid cultivars that are grown by farmers across various regions, thereby making this country a secondary center of diversity for this crop. A main topic of controversy in recent years refers to the unintended presence of transgenic events in locally grown cultivars at main centers of crop diversity. Peru does not yet have biosafety regulations to control or permit the growing of genetically modified crops. Hence, the aim of this research was to undertake a survey in the valley of Barranca, where there were recent claims of authorized transgenic maize grown in farmers fields as well as in samples taken from feed storage and...
Tipo: Journal article
Palavras-chave: Biosafety; Corn; Sampling; Transgenes; Zea mays.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400009

Phytoplasma and virus detection in commercial plantings of Vitis vinifera cv. Merlot exhibiting premature berry dehydration
Provedor de dados: Electronic Journal of Biotechnology
Autores: Matus,José Tomás; Vega,Andrea; Loyola,Rodrigo; Serrano,Carolina; Cabrera,Soledad; Arce-Johnson,Patricio.
A new and devastating physiological disorder of Vitis vinifera cv. Merlot was recently reported, known as premature berry dehydration (PBD), which is characterized by plant growth reduction, induction of general senescence and pedicel necrosis in the fruit, causing significant reductions in vineyard production. The causes of this disease remain unclear and previous reports suggest that it may be associated with phloem disruption and water provision. For this reason, any factor causing phloem disturbances could cause an important change in the berry water status. As some micro-organisms have been reported to disrupt phloem flow, we analyzed the occurrence of phytoplasma and viruses in commercial vineyards presenting PBD. In this study, a phytoplasma was...
Tipo: Journal article
Palavras-chave: Berry shrinkage; Candidatus phytoplasma mali; Late ripening; Over ripened; Pedicel necrosis; Phloem; Water transport.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000500007

Effect of edible quinoa protein-chitosan based films on refrigerated strawberry (Fragaria × ananassa) quality
Provedor de dados: Electronic Journal of Biotechnology
Autores: Valenzuela,Carolina; Tapia,Cristian; López,Luis; Bunger,Andrea; Escalona,Victor; Abugoch,Lilian.
Background Strawberries are non-climacteric fruits with a low respiration rate, but are subject to serious fungal deterioration during postharvest handling. The edible coatings based on chitosan (CH), quinoa protein-chitosan (Q/CH) and quinoa protein-chitosan-sunflower oil (Q/CH/SO) may provide a solution to this problem. Thus, in this work CH, Q/CH and Q/CH/SO were elaborated and applied to fresh strawberries, and its effect on the strawberries shelf life during storage for 15 d was evaluated by mold and yeast count, fungal decay, carbon dioxide rate, physicochemical properties, and sensory evaluation. Results On all analysis days, the strawberries coated with the film-forming CH, Q/CH and Q/CH/SO solutions presented a significant lower amount of mold and...
Tipo: Journal article
Palavras-chave: Chitosan; Edible films; Quinoa protein; Strawberry; Sunflower oil.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600004

Present and future of bioleaching in developing countries
Provedor de dados: Electronic Journal of Biotechnology
Autores: Acevedo,Fernando.
Nowadays bioleaching occupies an increasingly important place among the available mining technologies. Today bioleaching is no longer a promising technology but an actual economical alternative for treating specific mineral ores. An important number of the current large-scale bioleaching operations are located in developing countries. This situation is determined by the fact that several developing countries have significant mineral reserves and by the characteristics of bioleaching that makes this technique especially suitable for these countries because of its simplicity and low capital cost requirement. The current situation of commercial-size bioleaching operations and ongoing projects in developing countries is presented and discussed with especial...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200001

Effects of aroma quality on the biotransformation of natural 2-phenylethanol produced using ascorbic acid
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tian,Xun; Ye,Rui; Wang,Jingwen; Chen,Yifei; Cai,Baoguo; Guan,Shimin; Rong,Shaofeng; Li,Qianqian.
Background Natural 2-phenylethanol (2-PE) is an important flavoring that emits the aroma of roses. During biotransformation, the aroma quality of natural 2-PE is affected by its main by-products, which include butanol, isobutyric acid, butyric acid, and isovaleric acid. Thus, controlling undesirable by-product formation can reduce the effect of odor on 2-PE aroma quality. Results 2-PE was produced through biotransformation using l-phenylalanine as a substrate and glucose as a carbon source. Ascorbic acid was added to the system to improve the redox reaction and suppress the generation of by-products. Principal component analysis of the aroma quality of 2-PE was performed using an electronic nose. Similarity analysis revealed that the effects of four...
Tipo: Journal article
Palavras-chave: Aroma quality; Ascorbic acid; Biotransformation; By-products; 2-Phenylethanol.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400005

The influence of intelligence and emotions on the acceptability of genetically modified organisms
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sorgo,Andrej; Jausovec,Norbert; Jausovec,Ksenija; Puhek,Miro.
The purpose of the study was to explore the relation between the acceptance of genetically modified organisms, basic emotions, general (IQ), verbal (VIQ) and procedural (PIQ) intelligence. The sample comprised 123 students of psychology (N = 65; 52.8%) and pre-service teachers (N = 58; 47.2%). There were 52 (42.3%) females and 71 males (57.7%) from one of the Slovenian universities. The conclusions of the study are as follows: a) acceptability of genetically modified organisms cannot be considered as a single group, but each GMO should be considered separately. Plants and microorganisms are much more easily to be accepted than animals and usages others than for food are more acceptable. Females showed higher level of acceptance than males. b) Among...
Tipo: Journal article
Palavras-chave: Acceptability; Emotions; Genetically modified organisms; Intelligence.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000100001

Cutinase structure, function and biocatalytic applications
Provedor de dados: Electronic Journal of Biotechnology
Autores: Carvalho,Cristina M. L.; Aires-Barros,Maria Raquel; Cabral,Joaquim M. S.
This review analyses the role of cutinases in nature and their potential biotechnological applications. The cloning and expression of a fungal cutinase from Fusarium solani f. pisi, in Escherichia coli and Saccharomyces cerevisiae hosts are described. The three dimensional structure of this cutinase is also analysed and its function as a lipase discussed and compared with other lipases. The biocatalytic applications of cutinase are described taking into account the preparation of different cutinase forms and the media where the different types of enzymatic reactions have been performed, namely hydrolysis, esterification, transesterification and resolution of racemic mixtures. The stability of cutinase preparations is discussed, particularly in anionic...
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000300006

Radioactive trace in semi natural grassland: Effect of 40K in soil and potential remediation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ciuffo,Liliana Eugenia del Carmen; Belli,María.
The uptake of radionuclides by plant roots constitutes the main pathway for the migration of radiocaesium from soil to humans, via food chain. In this study we assessed radiocaesium uptake by plant in order to piece together information on factors affecting uptake processes, particularly K supply and differential uptake among different plant species. Soil contaminated by the Chernobyl accident and forage from a semi-natural alpine grassland, situated in Tarvisio, Italy, were sampled during 1999. Under field conditions, 137Cs uptake for Graminaceae and Taraxacum officinale seem to behave in a comparable way. Higher 40K soil activity concentration leads to a lower 137Cs plant uptake, suggesting an inhibitory pattern of potassium on radiocaesium plants...
Tipo: Journal article
Palavras-chave: 137Cs plant uptake; Radioactive traces; Radiocaesium; Radiopotassium.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300024

Equipment design for biosorption studies with microorganisms
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jensen,Thomas E; Crang,Mary C; Crang,Richard F.E.
Two laboratory devices have been designed for experimental use in biosorption studies involving the uptake and controlled release of elements from encapsulated living cells of microorganisms. The first device is an alginate bead maker capable of producing uniform (1.5 mm diameter) sodium alginate beads with encapsulated microorganisms. The second device is a flow-cell that can subject the encapsulated microorganisms to changing fluids, streaming gaseous microaerophyllic conditions, and which also allows for samples of fluid and beads to be extracted at any time during changing experimental conditions. Both devices are novel and simple in their design, and enable improved accuracy and precise handling of encapsulated specimens with minimal labour and...
Tipo: Journal article
Palavras-chave: Bead maker; Biosorption; Flow-cell; Sodium alginate.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400014

Medium optimization for palmarumycin C13 production in liquid culture of endophytic fungus Berkleasmium sp. Dzf12 using response surface methodology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhao,Jianglin; Wang,Xiaohan; Sun,Weibo; Mou,Yan; Peng,Youliang; Zhou,Ligang.
Background: Berkleasmium sp. Dzf12, an endophytic fungus from Dioscorea zingiberensis, was a high producer of palmarumycin C13 with various bioactivities. In the present study, the experimental designs based on statistics were employed to evaluate and optimize the medium for palmarumycin C13 production in mycelia liquid culture of Berkleasmium sp. Dzf12. Results: Among various carbon and nitrogen sources, glucose, peptone and yeast extract were found to be the most favourable for palmarumycin C13 production based on the one-factor-at-a-time experiments. After Plackett-Burman test on the medium, glucose, peptone and yeast extract were further verified to be the most significant factors to stimulate palmarumycin C13 accumulation. These three factors (i.e.,...
Tipo: Journal article
Palavras-chave: Berkleasmium sp. Dzf12; Central composite design; Endophytic fungus; Mycelia liquid culture; Palmarumycin C13; Plackett-Burman test; Response surface methodology.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600016

Construction and expression of two-copy engineered yeast of feruloyl esterase
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhou,Min; Huang,Zhiqing; Zhou,Bo; Luo,Yanliu; Jia,Gang; Liu,Guangmang; Zhao,Hua; Chen,Xiaoling.
Background Aspergillus niger has the ability to secrete feruloyl esterase. However, for economically viable industrial applications, it is necessary to increase their catalytic activities and/or protein yields to satisfy the increasing needs for feruloyl esterases. Results The gene AnFaeA that encodes a type A feruloyl esterase was successfully expressed in Pichia pastoris by a two-copy engineered yeast. After a screen in shaker flask, a one-copy strain GSKFA3 having the highest feruloyl esterase activity of 2.4 U/mL was obtained. Then, the pPICZaA-AnFaeA plasmid was transformed into GSKFA3 and the transformants were grown on YPDS plates with antibiotic Zeocin. After cultivation, a two-copy strain GSKZaFA20 with the highest feruloyl esterase activity of...
Tipo: Journal article
Palavras-chave: Aspergillus niger; Feruloyl esterase; Pichia pastoris.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500002

RNA interference revolution
Provedor de dados: Electronic Journal of Biotechnology
Autores: Thakur,Archana.
RNA interference (RNAi) is a potent method using only a few double stranded RNA (dsRNA) molecule per cell to silence the expression which has made it one of the hottest topics in molecular biology in last two years. Not long ago scientists conducted gene knock out using antisense, dominant negative or knockout techniques which were ineffective, but the discovery of RNAi has enabled to knock out gene in any organism efficiently. RNA silencing was first discovered in transgenic plants, where it was termed co-suppression or post transcriptional gene silencing (PTGS). Five years ago the evidence for RNA silencing emerged from experimental observation on Caenorhabditis elegans, this new approach for achieving efficient, targeted gene silencing is now making its...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000100007

Process design and sustainability in the production of bioethanol from lignocellulosic materials
Provedor de dados: Electronic Journal of Biotechnology
Autores: Scott,Felipe; Quintero,Julián; Morales,Marjorie; Conejeros,Raúl; Cardona,Carlos; Aroca,Germán.
Background: Bioethanol is produced mainly from sugar cane and corn. In the last years it has been subject of debate due to the effects in food prices and land use change. The use of lignocellulosic materials for bioethanol production, such as agroindustry, forestry and municipal residues, wood or dendroenergetic species, has been proposed as a sustainable way for producing this biofuel. The design of a sustainable process for producing bioethanol requires a methodological approach whereby economical, environmental and social criteria are systematically integrated from the early stages of process design. Results: Until now a methodology for guiding the design of a sustainable process for bioethanol production is not available, and there are just a few...
Tipo: Journal article
Palavras-chave: Bioethanol; Life cycle analysis; Lignocelluloses; Sustainability.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300013

Stenotrophomonas maltophilia isolated from gasoline-contaminated soil is capable of degrading methyl tert-butyl ether
Provedor de dados: Electronic Journal of Biotechnology
Autores: Alfonso-Gordillo,Guadalupe; Cristiani-Urbina,Eliseo; Flores-Ortiz,César Mateo; Peralta,Humberto; Cancino-Díaz,Juan Carlos; Cruz-Maya,Juan Antonio; Jan-Roblero,Janet.
Background: Methyl tert-butyl ether (MTBE) is a pollutant that causes deleterious effects on human and environmental health. Certain microbial cultures have shown the ability to degrade MTBE, suggesting that a novel bacterial species capable of degrading MTBE could be recovered. The goal of this study was to isolate, identify and characterize the members of a bacterial consortium capable of degrading MTBE. Results: The IPN-120526 bacterial consortium was obtained through batch enrichment using MTBE as the sole carbon and energy source. The cultivable fraction of the consortium was identified; of the isolates, only Stenotrophomonas maltophilia IPN-TD and Sphingopyxis sp. IPN-TE were capable of degrading MTBE. To the best of our knowledge, this report is the...
Tipo: Journal article
Palavras-chave: Bacterial consortium; Biodegradation; MTBE; Sphingopyxis sp; Stenotrophomonas maltophilia.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500003

Modulation of mitochondrial membrane integrity and ROS formation by high temperature in Saccharomyces cerevisiae
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Min; Shi,Jun; Jiang,Li.
Background Yeast strains are exposed to numerous environmental stresses during industrial alcoholic fermentation. High temperature accumulated acetic acid, enhanced the growth inhibition and decreased ethanol production. Results In this study the influence of high temperature on the cellular and mitochondrial membrane integrity of Saccharomyces cerevisiae as well as reactive oxygen species (ROS) formation was investigated to understand the mechanisms of the high temperature fermentation process. However, increasing the temperature to 42°C resulted in a clear decrease in the cytoplasmic and mitochondrial membrane potential and an increase in intracellular ROS formation. It was also determined that the different thermostability between YZ1 and YF31 strains...
Tipo: Journal article
Palavras-chave: Bioethanol; Random amplified polymorphic DNA (RAPD); Yeast.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300010

Three new shuttle vectors for heterologous expression in Zymomonas mobilis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cao,Qinghua; Li,Tao; Shao,Huanhuan; Tan,Xuemei; Zhang,Yizheng.
Background: Zymomonas mobilis, as a novel platform for bio-ethanol production, has been attracted more attention and it is very important to construct vectors for the efficient expression of foreign genes in this bacterium. Results: Three shuttle vectors ( pSUZM 1, pSUZM2 and pSUZM3 ) were first constructed with the origins of replication from the chromosome and two native plasmids (pZZM401 and pZZM402) of Z. mobilis ZM4, respectively. The three shuttle vectors were stable in Z. mobilis ZM4 and have 3,32 and 27 copies, respectively. The promoter Ppdc (a), from the pyruvate decarboxylase gene, was clonedinto the shuttle vectors, generatingthe expressionvectors pSUZM1(2, 3)a. The codon-optimized glucoamylase gene from Aspergillus awamori combined with the...
Tipo: Journal article
Palavras-chave: Expression vector; Gene expression; Glucoamylase; Zymomonas mobilis.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000100006

Association between biometric characteristics of tomato seeds and seedling growth and development
Provedor de dados: Electronic Journal of Biotechnology
Autores: Peñaloza,Patricia; Durán,José María.
Background The size and weight of tomato seeds depend on genetics and can be modified by environment and management. In some species, a strong relation has been described between physical aspects of the seeds and the quality of the corresponding seedlings, but this cannot be considered a general rule. The objective of this research was to identify any association between the biometric characteristics of tomato seeds and the growth and development of their seedlings. Results A total of 18 lots of hybrid tomato seeds were used (from indeterminate plants with round fruits), belonging to six varieties from two reproduction seasons. Each lot was evaluated for seed size and weight, and seed quality, in terms of the germination test (5 and 14 d after sowing). The...
Tipo: Journal article
Palavras-chave: Seed size; Seed weight; Seedling emergence; Seedling length; Seedlings dry weight; Solanum lycopersicum L.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400002

The future of biotechnology depends on quality science education
Provedor de dados: Electronic Journal of Biotechnology
Autores: Alberts,Bruce M.; Labov,Jay B.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300001

PCR-RFLP as a useful tool for diagnosis of invasive mycoses in a healthcare facility in the North of Brazil
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sousa,Diego Rayan Teixeira de; Santos,Carla Silvana da Silva; Wanke,Bodo; Silva Júnior,Roberto Moreira da; Santos,Marcelo Cordeiro dos; Cruz,Kátia Santana; Monte,Rossicléia Lins; Nocker,Andreas; Souza,João Vicente Braga de.
Background The incidence of invasive mycoses is increasing worldwide. PCR-RFLP was applied to the identification of 10 reference strains and 90 cultures of agents of invasive mycoses. In addition, the new approach was applied to detect fungal agents in 120 biological samples (blood, cerebrospinal fluid and bone marrow). PCR-RFLP results were compared with the ones obtained with conventional methods (culture, microscopy, and biochemical testing). Results The assays carried out with the reference strains (Candida albicans, Candida parapsilosis, Candida tropicalis, Candida krusei, Candida guilliermondii, Cryptococcus neoformans, Cryptococcus gattii and Histoplasma capsulatum), demonstrated that the RFLP profiles were correctly predicted by the in silico...
Tipo: Journal article
Palavras-chave: Pathogenic fungus; Polymorphism; Simultaneous analysis.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300014

Assessment of genetic diversity in Venezuelan rice cultivars using simple sequence repeats markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ghneim Herrera,Thaura; Posso Duque,Duina; Pérez Almeida,Iris; Torrealba Núñez,Gelis; Pieters,Alejandro J; Martinez,César P; Tohme,Joe M.
In Venezuela, pedigree analyses indicate that the rice varieties currently under cultivation are closely related. Effective breeding programs, based on knowledge of the genetic diversity of cultivars, are needed to broaden the genetic bases of rice germplasm in the country. In this study, we used a set of 48 simple-sequence-repeat (SSR) markers to assess the genetic diversity of 11 Venezuelan rice cultivars, released by the National Rice Breeding Program between 1978 and 2007. A total of 203 alleles were detected, the number of alleles (NA) per marker ranged from 2 to 9, with an average of 4.23. The average genic diversity (H) over all SSR loci for the 18 genotypes was 0.524, ranging from 0.105 to 0.815. Positive correlations were found between H at each...
Tipo: Journal article
Palavras-chave: DNA fingerprinting; Genetic diversity; Rice; SSR.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000500003

Optimization of transgenesis conditions for the generation of CXCL2-luciferase reporter mice line
Provedor de dados: Electronic Journal of Biotechnology
Autores: Crispo,Martina; Schlapp,Geraldine; Cárdenas-Rodríguez,Magdalena; González-Maciel,Dolores; Rumbo,Martín.
Background: Transgenesis by microinjection has been widely used for the generation of different mouse models. Different variables of the procedure may critically affect the efficiency of the process. A DNA construction that carries the CXCL2 promoter gene and firefly luciferase has been used to optimize aspects of the procedure. Three different concentrations (0.5, 1.0 and 4.0 ng/µl) of the DNA construction to microinject a total of 1981 zygotes has been tested. Intact/injected embryos, pregnancy and birth rate, survival of pups 7 days after birth, number of transgenic pups and overall transgenic efficiency was registered and analyzed by Z test of proportions for each group. Results: A total of seven transgenic founders were detected for the three DNA...
Tipo: Journal article
Palavras-chave: DNA concentration; Microinjection; Reporter systems.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600014

Application of palm pressed fiber as a carrier for ethanol production by Candida shehatae TISTR5843
Provedor de dados: Electronic Journal of Biotechnology
Autores: Riansa-ngawong,Wiboon; Suwansaard,Maneewan; Prasertsan,Poonsuk.
Palm pressed fiber (PPF) is a clean and renewable lignocellulosic material. The PPF and delignified PPF (DPPF) were used as a carrier for immobilization of Candida shehatae TISTR5843 in bioethanol production. PPF was pre-treated by milling to obtain small particles, whereas DPPF was the delignification of PPF using NaClO2. C. shehatae TISTR5843 was grown in modified yeast extract- malt (YM) medium at 30 ± 2ºC on an orbital shaker at 150 rpm for batch and repeated batch fermentation. In the batch system, immobilized cells on a small size, less than 0.5 mm, of DPPF (sDPPF) gave the maximum ethanol production of 11.5 g L-1 at 24 hrs cultivation period. The ethanol concentration and ethanol yield of sDPPF were 6.2% and 6.8% higher (ethanol production 11.5 g...
Tipo: Journal article
Palavras-chave: Candida shehatae; Ethanol production; Immobilization; Palm pressed fiber.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600001

Enhancement of botrallin and TMC-264 production in liquid culture of endophytic fungus Hyalodendriella sp. Ponipodef12 after treatments with metal ions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Luo,Haiyu; Xu,Dan; Xie,Rushan; Zhang,Xuping; Wang,Jian; Xuejiao,Dong; Lai,Daowan; Zhou,Ligang; Liu,Yang.
Background: Hyalodendriella sp. Ponipodef12, an endophytic fungus from a poplar hybrid, was a high producer of botrallin and TMC-264 with various bioactivities. In this study, the influences of eight metal ions (i.e.,Mn2+,Na+, Mg2+,Zn2+,Cu2+,Fe2+,Fe3+ and Al3+) on botrallin and TMC-264 production in liquid culture of the endophytic fungus Hyalodendriella sp. Ponipodef12 were investigated. Results: Three most effective metal ions (Zn2+,Cu2+ and Mg2+) along with their optimum concentrations were screened. The optimum addition time and concentrations of Zn2+,Cu2+ and Mg2+ were further obtained respectively for improving botrallin and TMC-264 production. The combination effects of Zn2+,Cu2+ and Mg2+ on the production of botrallin and TMC-264 by employing...
Tipo: Journal article
Palavras-chave: Combination effects; Production; Microbial biotechnology; Process biotechnology; Bioactivities; Central composite design; Response surface methodology.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600002

BIOLOGICAL WARFARE, BIOTERRORISM, BIODEFENCE AND THE BIOLOGICAL AND TOXIN WEAPONS CONVENTION
Provedor de dados: Electronic Journal of Biotechnology
Biological warfare is the intentional use of micro-organisms, and toxins, generally of microbial, plant or animal origin to produce disease and death in humans, livestock and crops. The attraction of bioweapons in war, and for use in terroristic attacks is attributed to easy access to a wide range of disease-producing biological agents, to their low production costs, to their non-detection by routine security systems, and to their easy transportation from one place to another. In addition, novel and accessible technologies give rise to proliferation of such weapons that have implications for regional and global security. In counteraction of such threats, and in securing the culture and defence of peace, the need for leadership and example in devising...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000300001

Bioconversion of (+)- and (-)-alpha-pinene to (+)- and (-)-verbenone by plant cell cultures of Psychotria brachyceras and Rauvolfia sellowii
Provedor de dados: Electronic Journal of Biotechnology
Autores: Limberger,Renata Pereira; Aleixo,Adriana Mendes; Fett-Neto,Arthur Germano; Henriques,Amélia T.
This work describes the bioconversion of (-)- and (+)-alpha-pinene (2,6,6-trimethyl-bicyclo[3.1.1]hept-2-ene), targeted at the production of (-)- and (+)-verbenone (4,6,6-trimethyl-bicyclo (3.1.1) hept-3-en-2-one), respectively, using Psychotria brachyceras and Rauvolfia sellowii cell suspension cultures. P. brachyceras showed selectivity to (-)-alpha-pinene with 80.9% conversion (relative integrated area gas chromatography-mass spectrometry (GC-MS)) of (-)-verbenone in 10-day-incubation, whereas R. sellowii was able to convert both pinene enantiomers (37.6% conversion of (-)-verbenone in 7-day-incubation and 32.2% conversion of (+)-verbenone in 10-day-incubation). In both systems trans-verbenol was formed as main product and then slowly biocatalyzed to...
Tipo: Journal article
Palavras-chave: Alpha-pinene; Biotransformation; Verbenol; Verbenone.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400003

Advances in improving mammalian cells metabolism for recombinant protein production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Altamirano,Claudia; Berrios,Julio; Vergara,Mauricio; Becerra,Silvana.
Background: The production of recombinant proteins for therapeutic use represents a great impact on the biotechnology industry. In this context, established mammalian cell lines, especially CHO cells, have become a standard system for the production of such proteins. Their ability to properly configure and excrete proteins in functional form is an enormous advantage which should be contrasted with their inherent technological limitations. These cell systems exhibit a metabolic behaviour associated with elevated cell proliferation which involves a high consumption of glucose and glutamine, resulting in the rapid depletion of these nutrients in the medium and the accumulation of ammonium and lactate. Both phenomena contribute to the limitation of cell...
Tipo: Journal article
Palavras-chave: Aerobic glycolysis; Cell engineering; CHO cells; Glutaminolysis; Metabolism.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300010

Enhancement of Escherichia coli cellulolytic activity by co-production of beta-glucosidase and endoglucanase enzymes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rodrigues,André L; Cavalett,Angélica; Lima,André O.S.
Cellulase is a group of enzymes (endoglucanase, exoglucanase and beta-glucosidase) required for cellulosic feedstock hydrolysis during bioethanol production. The use of recombinant cellulase is a strategy to reduce the enzyme cost. In this context, the present work describes the construction of a cellulase expression vector (pEglABglA), which allowed constitutive co-expression of endoglucanase A (EglA) from an endophytic Bacillus pumilus and the hyperthermophilic &amp;#946;-glucosidase A (BglA) from Fervidobacterium sp. in Escherichia coli. When compared to the non-modified strain DH5&amp;#945;, the recombinant Escherichia coli DH5&amp;#945; (pEglABglA) reduced fivefold the viscosity of the carboxymethylcellulose medium (CMC-M). Also, it presented almost...
Tipo: Journal article
Palavras-chave: Beta-glucosidase; Cellulase cassette; Cellulose bioconversion; Endoglucanase; Heterologous expression.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500005

Degradation of methomyl by the novel bacterial strain Stenotrophomonas maltophilia M1
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mohamed,Mervat S.
The use of microorganisms in the degradation and detoxification of many toxic xenobiotics, especially pesticides, is an efficient tool for the decontamination of polluted sites in the environment. A novel bacterial strain (M1) was isolated from several water samples contaminated with methomyl which is capable of degrading methomyl pesticide (1000 ppm) in the presence of 0.05% glucose. These water samples were collected from different irrigation sites in Egypt where methomyl is heavily applied. The partial sequence of 16SrRNA gene of the isolate showed the highest similarity to Stenotrophomonas maltophilia. Restriction fragment patterns of isolated plasmid DNA showed that this strain harbours two different plasmids PMa (8Kb) and PMb (5Kb). PMb succeeded to...
Tipo: Journal article
Palavras-chave: Carbamate; Methomyl; Plasmid; SPE-LC-ESI-MS; Stenotrophomonas.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400006

Inbreeding evidence in a traditional channel catfish (Ictalurus punctatus) hatchery in Mexico
Provedor de dados: Electronic Journal of Biotechnology
Autores: Parra-Bracamonte,Gaspar Manuel; Sifuentes-Rincón,Ana María; Rosa-Reyna,Xochitl Fabiola De la; Arellano-Vera,Williams; Sosa-Reyes,Brenda.
Background: Channel catfish are one of the most important aquaculture species raised for food purposes in Mexico. Two temporal samples were obtained from the largest channel catfish breeding hatchery in Mexico to identify changes in genetic diversity and inbreeding that are promoted by traditional hatchery management. Results: The genetic parameter analysis of 11 microsatellite loci showed no significant change in genetic diversity (p &amp;gt; 0.05). However, a significant heterozygosis deficiency was detected (p &lt; 0.001), and genetic structure analysis indicated moderate differentiation between the temporally divided populations (F ST = 0.08). A moderate level of inbreeding and a slight increase of the inbreeding coefficient from 0.23 to 0.27 were the...
Tipo: Journal article
Palavras-chave: Channel catfish; Effective population size; Genetic diversity; Inbreeding.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600011

Chloroperoxidase mediated oxidation of chlorinated phenols using electrogenerated hydrogen peroxide
Provedor de dados: Electronic Journal of Biotechnology
Autores: La Rotta,Camilo E; D'Elia,Eliane; Bon,Elba P.S.
Chloroperoxidase (CPO) from Caldariomyces fumago catalyses the oxidation of several chlorinated phenols (CP) commonly found in industrial waste waters in the presence of hydrogen peroxide. This study compares the direct addition of hydrogen peroxide (DA) with its continuous electrogeneration (EG) during the enzymatic oxidation of CP. Reaction mixtures were studied containing chemically modified CPO, hydrogen peroxide and the phenolic substrates: phenol (P), 4-chlorophenol (4-CP), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP), in 100 mM sodium-potassium phosphate buffer pH 6.0, at 25ºC. Results were compared in terms of residual phenol concentration (oxidation efficiency), precipitate formation (removal) and...
Tipo: Journal article
Palavras-chave: Biodegradation; Bioelectrochemistry; Caldariomyces fumago; Chlorinated phenols; Chloroperoxidase; Hydrogen peroxide electrogeneration.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100003

Citric acid production from glucose by yeast Candida oleophila ATCC 20177 under batch, continuous and repeated batch cultivation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Anastassiadis,Savas; Rehm,Hans-Jürgen.
The effect of air saturation on citric acid production in batch, repeated batch and chemostat cultures has been studied. It was shown that, under continuous fermentation (chemostat mode), the highest concentration of citric acid equal of 98 g/l was produced at 20% of air saturation. In contrary to continuous fermentation, displaying an optimum at 20%, 80% air saturation yielded higher values in repeated batch fermentation process. 167 g/l citric acid were produced continuously with the fill and drain technique at 4.85 days, at 80% air saturation, compared with 157.6 g/l achieved within 5.4 days at 20%. Under repeated batch fermentation, the formation rate of the generic product (Rj) as well as the specific citric acid productivity (m p) reached a maximum...
Tipo: Journal article
Palavras-chave: Air saturation influence; Chemostat; Citric acid; Citric acid fermentation; Repeated batch; Oxygen influence.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100005

Biotechnology research in Venezuela: Five case studies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Morales,Rosa.
The organization of biotechnology differs across countries. The structure of the industry, the academia, and the links between these two sectors vary according to which country is studied. Biotechnology is organized in Venezuela mainly around the research done by special research and development units at national universities. The paper describes some of these units in order to shed light about their performance. Two economic approaches are used to explain the academic production of these biotech research organizations: the technological and organizational approaches. A case study methodology is used in this research. The results can be summarized as: The percentage of researchers who are doctors is less than seventy percent in each research and...
Tipo: Journal article
Palavras-chave: Human capital; Latin American biotechnology; Research and development units; Organization of biotechnology.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500001

Ion pumps as targets for therapeutic intervention: Old and new paradigms
Provedor de dados: Electronic Journal of Biotechnology
Autores: Perlin,David S.
The development of an effective target for therapeutic intervention remains a critical part of the drug discovery process. One such target class is the P-type ion translocating ATPases, which include the Na+,K+-ATPase of cardiac cells and the H+,K+-ATPase of gastric parietal cells. These enzymes serve as selective targets for digoxin and omeprazole, which are used to treat heart disease and gastrointestinal ulcers, and are two of the leading prescribed therapeutics worldwide. It is the exquisite selectivity that can be achieved between family members that continues to make the P-type enzymes desirable targets for developing new therapeutics including a new generation of antiulcer therapeutic and a new class of antifungal therapeutic.
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000200002

Genome analysis of thirteen Colombian clostridial strains by pulsed field gel electrophoresis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Quilaguy Ayure,Diana Milena; Suárez Moreno,Zulma Rocío; Aristizábal Gutierrez,Fabio Ancizar; Bernal Morales,Jose Mauricio; Montoya Castaño,Dolly.
Pulsed field gel electrophoresis was used for estimating the size of the genome and evaluating the presence of megaplasmids in 13 native Colombian solventogenic Clostridium strains. DNA preparation and purification were optimised for obtaining differentiated restriction fragments in electrophoresis. Genomic DNA was digested with ApaI, Eco52I, SmaI and XhoI enzymes. Estimated genome size for native strains ranged from 4.0 to 4.2 mega base pairs. Larger sized plasmids were detected and the presence of genes related to megaplasmid pSOL1 was determined by polymerase chain reaction. adc gene region amplification suggested that genes related to solventogenesis in native strains may be located in an extra-chromosomal element. Determining genome size provides...
Tipo: Journal article
Palavras-chave: Clostridium; Genome size; PFGE; PSOL1.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500009

A novel chloroplastic isopentenyl diphosphate isomerase gene from Jatropha curcas: Cloning, characterization and subcellular localization
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wei,Lei; Yin,Li; Hu,Xiaole; Xu,Ying; Chen,Fang.
Background Jatropha curcas is a rich reservoir of pharmaceutically active terpenoids. More than 25 terpenoids have been isolated from this plant, and their activities are anti-bacterial, anti-fungal, anti-cancer, insecticidal, rodenticidal, cytotoxic and molluscicidal. But not much is known about the pathway involved in the biosynthesis of terpenoids. The present investigation describes the cloning, characterization and subcellular localization of isopentenyl diphosphate isomerase (IPI) gene from J. curcas. IPI is one of the rate limiting enzymes in the biosynthesis of terpenoids, catalyzing the crucial interconversion of isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). Results A full-length JcIPI cDNA consisting of 1355 bp was cloned....
Tipo: Journal article
Palavras-chave: Heterologous expression; Southern blot; Terpenoids; Transient expression.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600007

Segregation distortion in homozygous lines obtained via anther culture and maize doubled haploid methods in comparison to single seed descent in wheat (Triticum aestivum L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Adamski,Tadeusz; Krystkowiak,Karolina; Kuczynska,Anetta; Mikolajczak,Krzysztof; Ogrodowicz,Piotr; Ponitka,Aleksandra; Surma,Maria; Slusarkiewicz-Jarzina,Aurelia.
Background The quality of wheat grain depends on several characteristics, among which the composition of high molecular weight glutenin subunits, encoded by Glu-1 loci, are the most important. Application of biotechnological tools to accelerate the attainment of homozygous lines may influence the proportion of segregated genotypes. The objective was to determine, whether the selection pressure generated by the methods based on in vitro cultures, may cause a loss of genotypes with desirable Glu-1 alleles. Results Homozygous lines were derived from six winter wheat crosses by pollination with maize (DH-MP), anther culture (DH-AC) and single seed descent (SSD) technique. Androgenetically-derived plants that originated from the same callus were examined before...
Tipo: Journal article
Palavras-chave: Androgenesis; DH lines; HMW glutenin subunits; SSD technique; Winter wheat.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100002

Effects of culture filtrates of endophytic fungi obtained from Piper aduncum L. on the growth of Mycobacterium tuberculosis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lima,Alita Moura de; Salem,Júlia Ignez; Souza,João Vicente Braga de; Cortez,Ana Claudia Alves; Carvalho,Clarice Maia; Chaves,Francisco Célio Maia; Veiga Junior,Valdir Florêncio da.
Substances that inhibit the growth of Mycobacterium tuberculosis could potentially be used as antibiotics. These substances could also be added to test culture media to improve the speed of tuberculosis diagnosis. The aim of this work was to investigate the influence of culture filtrates of endophytic fungi isolated from P. aduncum L. on the growth of M. tuberculosis. To achieve this objective, the following methodology was used: a) endophytic fungi were isolated from the leaves and stems of P. aduncum L.; b) the isolated fungi were submitted to submerged bioprocessing; c) culture filtrates from the bioprocess were assayed to evaluate their effect on the growth of M. tuberculosis. We isolated 315 fungal types, which represented 85 morphologies, from...
Tipo: Journal article
Palavras-chave: Antagonism; Stimulation growth; Tuberculosis.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400008

Culture conditions for the production of a-galactosidase by Aspergillus parasiticus MTCC-2796: a novel source
Provedor de dados: Electronic Journal of Biotechnology
Autores: Shivam,Kumar; Tripathi,Chandra Prakash Mani; Mishra,Sarad Kumar.
Aspergillus parasiticus microbial type culture collection (MTCC)-2796, a new source of a-galactosidase is an efficient producer of enzyme in basic medium under submerged fermentation conditions. Maximum a-galactosidase production (156.25 Uml-1) was obtained when the basic medium is supplemented with galactose (0.5% w/v) and raffinose (0.5% w/v) as carbon source and yeast extract as nitrogen source. Enzyme production was also enhanced considerably in the presence of wheat bran (1.0% w/v). Enzyme secretion was strongly inhibited by the presence of Hg2+, Cu2+, and Co2+ in the medium and to some extent by Zn2+ and Ni2+, while marginal increase in the enzyme production was observed when Mg2+ and Mn2+ were added in the medium. Among amino acids checked...
Tipo: Journal article
Palavras-chave: Aspergillus parasiticus; A-galactosidase; Culture condition; Submerged fermentation.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400004

Multiple pulses improve electroporation efficiency in Agrobacterium tumefaciens
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mahmood,Tariq; Zar,Tamkina; Saqlan Naqvi,S.M.
Electroporation entails brief, high intensity pulse to create transient pores in the cell membrane to facilitate the entry of exogenous macromolecules, which may otherwise be excluded. Removal of the external field leads to the resealing of the membrane electropores permitting the survival of the electrically stimulated recipient cells. Using this technique foreign deoxyribonucleic acid (DNA) has been successfully introduced into many cell types both from prokaryotes and eukaryotes. Increase in pulse voltage and length beyond a critical limit has been reported to decrease transformation efficiency, hence in this study we have investigated another strategy i.e. increase in the number of pulses at constant high voltage and pulse duration. Commonly used...
Tipo: Journal article
Palavras-chave: Agrobacterium; Electroporation; Pulse number; Transformation efficiency.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100015

Biosafety information management systems. A comparative analysis of the regulatory systems in Canada, Argentina, and Chile
Provedor de dados: Electronic Journal of Biotechnology
Autores: Flint,Jason; Irarrazabal,Carlos; Dellacha,Juan.
CamBioTec, a Canadian-Latin American Network promoting the safe and effective use of agricultural and environmental biotechnology, undertook an analysis of the current capacities of Argentina, Chile and Canada with respect to the management of information related to assessment and approval of products of modern biotechnology/ genetically engineering. This report is based on data obtained during a number of interviews and institutional visits conducted during August 1998 and includes: an overview of current regulatory policy, identification of key human resources and authorities, analysis of information management capacity, recommendations for capacity building, and descriptions of relevant international initiatives. Canada has a regulatory system in place...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000100002

Macromolecular composition and anaerobic degradation of the sludge produced in a sequencing batch reactor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chelme,Susana; Fonseca,Pamela; Mercado,Rodrigo; Alarcon,Nelson; Sánchez,Omar.
The effect of sequencing batch reactor (SBR) operating conditions on sludge macromolecular composition and the effect of sludge macromolecular composition on the anaerobic degradation of the sludge produced in SBR was investigated in this work. A SBR, fed with synthetic wastewater, was operated at different air flow rates. The resulting sludge was analyzed in terms of protein, carbohydrate, phospholipid and polyhydroxybutyrate concentrations. Methane production during anaerobic digestion of the sludge was also measured. Ammonium, nitrite, nitrate, dissolved oxygen and chemical oxygen demand (COD) track studies in the SBR were carried out in order to relate SBR performance and sludge macromolecular composition. The lowest air flow rate at which the SBR was...
Tipo: Journal article
Palavras-chave: Anaerobic digestion; Sequencing batch reactor; Sludge.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300010

The bacterial community structure in an alkaline saline soil spiked with anthracene
Provedor de dados: Electronic Journal of Biotechnology
Autores: Castro-Silva,Carolina; Ruíz-Valdiviezo,Víctor M; Valenzuela-Encinas,César; Alcántara-Hernández,Rocio J; Navarro-Noya,Yendi E; Vázquez-Núñez,Edgar; Luna-Guido,Marco; Marsch,Rodolfo; Dendooven,Luc.
Background: The application of polycyclic aromatic hydrocarbons (PAHs) will affect the bacterial community structure as some groups will be favoured and others not. An alkaline saline soil with electrolytic conductivity (EC) 56 dS m-1 was spiked with anthracene and acetone while their effect on bacterial community structure was investigated. Results: The percentages of Acidobacteria and Actinobacteria decreased over time, while the percentage of Proteobacteria, mostly Xanthomonadales, increased. The percentage of the phylotypes belonging to the Nocardioides, Rhodococcus and Streptomyces, known degraders of PAHs, was larger in the anthracene-amended soil than in the acetone-amended and unamended soil at day 14. The phylotypes belonging to the genera...
Tipo: Journal article
Palavras-chave: C dynamics; N mineralization; Phylogenetic analysis; Polycyclic aromatic hydrocarbons; Principal component analysis; UniFrac.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500010

Cloning and expression of S-Adenosyl Methionine Synthetase gene in recombinant E. coli strain for large scale production of SAMe
Provedor de dados: Electronic Journal of Biotechnology
Autores: Detchanamurthy,Swaminathan; Shanmugam,Kirubanandan; Parkunan,Salai Madhumathi Arasi; Puttananjaiah,Shilpa; Somasundaram,Balaji; Subramanian,Kannan.
S-Adenosyl Methionine (SAMe) Synthetase is an enzyme which catalyses the synthesis of S-Adenosyl Methionine using methionine and ATP. It is also known as AdoMet which is well known methyl donor, which modifies DNA, RNA, histones and other proteins, dictating replicational, transcriptional and translational fidelity, mismatch repair, chromatin modeling, epigenetic modifications and imprinting. The objective of the present work is to clone the SAMe Synthetase gene in recombinant E. coli strain in order to express, characterize and purify it for further synthesis of SAMe in a large scale fermentation. Expression was induced by 1 mM IPTG and expressed protein was characterized by SDS-PAGE. The recombinant E. coli cells were used for the production of SAMe...
Tipo: Journal article
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400001

High genetic diversity and small genetic variation among populations of Magnolia wufengensis (Magnoliaceae), revealed by ISSR and SRAP marker
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chen,Liyuan; Chen,Faju; He,Suichao; Ma,Luyi.
Background Genetic diversity and genetic variation of 10 populations and subpopulations of Magnolia wufengensis, a new and endangered endemic species, were examined by inter simple sequence repeat (ISSR) and sequence-related amplified polymorphism (SRAP) molecular markers. Compared with other endangered endemic Magnolia taxa, M. wufengensis holds a relatively high level of genetic variation. Result Total genetic diversity was found to be 87.7% for ISSR and 88.0% for SRAP markers. For polymorphic loci (P), the effective mean number of alleles (Ae) was 1.414 for ISSR markers and 1.458 for SRAP markers, while the mean expected heterozygosity (H) was 0.256 using ISSR and 0.291 for SRAP markers. Within-population variation was estimated for P as 74.9% using...
Tipo: Journal article
Palavras-chave: Genetic structure; ISSR; Population genetic diversity; SRAP.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600003

Heterozygosity following half-sib recurrent selection in popcorn using isoenzyme markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pereira,Liz Kazmirczak; Scapim,Carlos Alberto; Mangolin,Claudete Aparecida; Machado,Maria de Fátima Pires da Silva; Pacheco,Cleso Antônio Patto; Mora,Freddy.
Isozyme biochemical marker may be useful tool for genomic analysis of maize populations undergoing recurrent selection. Thus, isozymes markers was utilized for assess the changes in the genetic variability and distance in a Brazilian composite population of popcorn following four cycles of recurrent selection for yield. One hundred and ninety-six half-sib families were evaluated from each cycle and the ten highest-yielding families (5.2%) were recombined to produce the next cycle. Isozyme analysis considered 80 seedlings per cycle. Simple linear regression equations were estimated among the allele frequencies in each locus in function of the selection cycles, the genetic distances among the cycles and the average heterozygosity per locus for each cycle....
Tipo: Journal article
Palavras-chave: Allozymes frequency; Genetic distance; Selection cycles; Zea mays.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100004

Genetic polymorphism of the &amp;#945;s1-casein locus in five populations of goats from Mexico
Provedor de dados: Electronic Journal of Biotechnology
Autores: Torres-Vázquez,José Antonio; Vázquez Flores,Felícitas; Montaldo,Hugo H; Ulloa-Arvizu,Raúl; Valencia Posadas,Mauricio; Gayosso Vázquez,Amanda; Alonso Morales,Rogelio Alejandro.
With the objective of estimating allele frequencies, and testing for population divergence for the CSN1S1 locus, genotypes of animals from five goat populations; Saanen (n = 97), Alpine (n = 81) Toggenburg (n = 92), local goats with external appearance similar to the Murciana-Granadina breed from Central Mexico (n = 26) and heterogeneous local animals denominated Mosaico Lagunero (n = 30), from Northern Mexico, were identified using PCR and Xmn1 PCR-RFLP methodology. For Saanen, Alpine and Toggenburg, the sum of E and F alleles had the largest frequencies (from 0.468 to 0.789), while for the groups local Murciana-Granadina and Mosaico Lagunero the sum of the most frequent allelic groups (A* and B*), were 0.385 and 0.533 respectively. Both local...
Tipo: Journal article
Palavras-chave: CSN1S1; Gene frequencies; Genetic diversity; Goat milk; PCR-RFLP.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300007

Identification of groundnut (Arachis hypogaea) SSR markers suitable for multiple resistance traits QTL mapping in African germplasm
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ncube Kanyika,Busisiwe T; Lungu,Davies; Mweetwa,Alice M; Kaimoyo,Evans; Njung'e,Vincent M; Monyo,Emmanuel S; Siambi,Moses; He,Guohao; Prakash,Channapata S; Zhao,Yongli; de Villiers,Santie M.
Background This study aimed to identify and select informative Simple Sequence Repeat (SSR) markers that may be linked to resistance to important groundnut diseases such as Early Leaf Spot, Groundnut Rosette Disease, rust and aflatoxin contamination. To this end, 799 markers were screened across 16 farmer preferred and other cultivated African groundnut varieties that are routinely used in groundnut improvement, some with known resistance traits. Results The SSR markers amplified 817 loci and were graded on a scale of 1 to 4 according to successful amplification and ease of scoring of amplified alleles. Of these, 376 markers exhibited Polymorphic Information Content (PIC) values ranging from 0.06 to 0.86, with 1476 alleles detected at an average of 3.7...
Tipo: Journal article
Palavras-chave: Arachis; African varieties; Disease; SSR.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200001

Natural selection for efficiency in the use of nitrogen in common bean identified by analysis of microsatellites and grain yield
Provedor de dados: Electronic Journal of Biotechnology
Autores: Leite,Monik Evelin; Lima,Igor Almeida; Pereira,Dyanna Rangel; Santos,João Bosco dos.
This study was carried out in order to verify whether natural selection acts on segregating common bean populations grown in the presence and absence of N, and to verify that natural selection affects the frequency of microsatellite alleles specifically, and in order to identify those that can assist in selection. Four populations from the crosses Ouro Negro x CI-107 and VC-5 x IAPAR-81 were carried forward in bulk to F8 at both levels of N. Ouro Negro and VC-5 are considered stress tolerant to nitrogen and IAPAR-81 and CI-107 responsive. One hundred progenies were obtained from each cross and grown in the presence and absence of N. DNA was extracted from 400 progenies, of which 194 were evaluated in the rainy season and 79 in the winter crop for grain...
Tipo: Journal article
Palavras-chave: Adaptation; Nitrogen use efficiency; Phaseolus vulgaris; SSR markers.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600005

Induction of somatic embryogenesis as an example of stress-related plant reactions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zavattieri,Maria Amely; Frederico,António Miguel; Lima,Mónica; Sabino,Rui; Arnholdt-Schmitt,Birgit.
In this review, we address the role of stress as one of the principal causes for a cell or tissue to change its pre-existing somatic program, reprogramming itself to express the embryogenic pathway. The focus of this paper is the effect of different stress conditions on the induction phase of plant somatic embryogenesis, as well as the development of embryogenic competence as a result of the applied stresses. We also present a variety of data that link plant somatic embryogenesis, DNA methylation and oxidative stress response.
Tipo: Journal article
Palavras-chave: Cell reprogramming; Reactive oxygen species; Somatic embryogenesis; Stress.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100012

EDITORIAL ELECTRONIC JOURNAL OF BIOTECHNOLOGY ....MOVING FROM SCIENCE TO DEVELOPMENT...: The need to strength collaborative teams in lung cancer research
Provedor de dados: Electronic Journal of Biotechnology
Autores: Adonis,Marta; Gil,Lionel.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000200001

Kinetic characteristics of &amp;#946;-cyclodextrin production by cyclodextrin glycosyltransferase from newly isolated Bacillus sp. C26
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cheirsilp,Benjamas; Kitcha,Suleeporn; Maneerat,Supasilp.
The kinetic characteristics of &amp;#946;-cyclodextrin production by a cyclodextrin glycosyltransferase (CGTase) produced by Bacillus sp. C26, a new isolate from a soil sample was investigated. Considering highest yield and initial production rate of &amp;#946;-cyclodextrin, among the starches examined, soluble starch, tapioca starch, sago starch, corn starch and rice starch, tapioca starch was the best substrate for this CGTase. The optimum temperature for tapioca starch gelatinization prior to its use as a substrate for &amp;#946;-cyclodextrin production was 65ºC. The yield and initial production rate of &amp;#946;-cyclodextrin increased with increasing starch concentration up to 6% and an enzyme concentration up to 48 U/g-starch. The kinetic parameters...
Tipo: Journal article
Palavras-chave: Bacillus subtilis ZK8; Cell adsorption; Jiean- peptide; Response surface methodology; Wood chips.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400004

Sequential use of ammonium and leucine as nitrogen sources during growth of Geotrichum candidum on a glucose based medium
Provedor de dados: Electronic Journal of Biotechnology
Autores: Adour,Lydia; Bude,Florence; Amrane,Abdeltif.
Geotrichum candidum growth on ammonium and leucine as nitrogen sources and glucose as a carbon source was examined. A clear preference of G. candidum for ammonium over leucine as a nitrogen source was shown. Indeed, ammonium was completely exhausted at the end of exponential growth after less than 35 hrs of culture; in contrast only 5% of leucine was concomitantly assimilated. Growth continued at slower rates on glucose and leucine as carbon and nitrogen sources respectively, and at the end of culture (185 hrs), leucine was completely exhausted.
Tipo: Journal article
Palavras-chave: Amino acids; Batch culture; Diauxic growth; Geotrichum candidum; Growth kinetics.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100013

Optimization of worm-bed leachate for culturing of tomato (Lycopersicon esculentum Mill) inoculated with Glomus fasciculatum and Pseudomonas fluorescens
Provedor de dados: Electronic Journal of Biotechnology
Autores: Oliva-Llaven,María Ángela; Rodríguez-Hernández,Ludwi; Mendoza-Nazar,Paula; Ruiz-Sesma,Benigno; Álvarez-Solís,José David; Dendooven,Luc; Gutiérrez-Miceli,Federico A.
A response surface technique was used to analyze the effect of Glomus fasciculatum, Pseudomonas fluorescens and worm-bed leachate (WBL) on growth, yield and characteristics of tomato (Lycopersicon esculentum Mill). The treatments combined inoculation with or without P. fluorescensor G. fasciculatum and the application of WBL at 20% (v/v) each day or every three days. Plant height, number of leaves and yield of tomato fruits was not affected by the factors studied. However, plants with foliar application of WBL each day developed wider stems than those with an application every three days. The pH of the fruits was lower when WBL was applied every three days compared to a daily application. The soluble solids content of the fruits was higher when WBL was...
Tipo: Journal article
Palavras-chave: Glomus fasciculatum; Organic cultivation of tomato; PH in tomato fruit; Soluble solids.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000200004

Analysis of genomic sequences from peanut (Arachis hypogaea)
Provedor de dados: Electronic Journal of Biotechnology
Autores: B,Jayashree; Ferguson,Morag; Ilut,Dan; Doyle,Jeff; Crouch,Jonathan H.
Peanut is an important legume crop across the world. However, in contrast to most legume crops, groundnut lacks taxonomic proximity to any major model genome. A relatively large number of genomic sequences were generated from groundnut as part of a microsatellite marker development project. In the current study, a total of 1312 sequences were analyzed of which 448 contained microsatellite motifs. All sequences (GenBank Accessions: BZ999351-CC000573) were analyzed after clustering for possible similarity with publicly available sequences from Arabidopsis, Lotus, soybean and Medicago. At least 39% of the sequences analyzed had significant BLAST similarities with sequences from the four databases searched, of which nearly half (47%) found significant...
Tipo: Journal article
Palavras-chave: Arachis hypogaea; Codon usage; Gene-based markers; Peanut; SSR markers.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300002

Plant biotechnology: a tool for development in Africa
Provedor de dados: Electronic Journal of Biotechnology
Autores: Brink,Johan A; Woodward,Barbara R; DaSilva,Edgar J.
Africa is, paradoxically, a continent rich in resources, and yet, lacking and lagging in overall development. When the wealth of Africa’s people is compared with that of other continents a contrasting picture of poverty, stunted growth and famine resulting from inadequate food production is revealed. Applying plant biotechnology alone cannot solve the agricultural and food security problems in Africa. Five key factors seem to be necessary for the improvement of crop production: they are the use of agrochemicals, irrigation, plant breeding, farm management, and, of course, plant biotechnology. In this context, biotechnology can play a role in commercializing crops, creating new jobs and earning foreign exchange. The goals of national and regional...
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000300004

International experience in human resource development in biotechnology: achievements and lessons learnt
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tatsuji,Seki; Toshiomi,Yoshida; Takuya,Nihira; DaSilva,Edgar.
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200003

Fermentation of rice bran hydrolysate to ethanol using Zymomonas mobilis biofilm immobilization on DEAE-cellulose
Provedor de dados: Electronic Journal of Biotechnology
Autores: Todhanakasem,Tatsaporn; Narkmit,Tipong; Areerat,Kamonchanok; Thanonkeo,Pornthap.
Background The major challenges associated with the fermentation of lignocellulosic hydrolysates are the reduction in the operating cost and minimizing the complexity of the process. Zymomonas mobilis biofilm has been emerged to resolve these complexities. Biofilm has been reported to tolerate to the toxic inhibitors and easily manipulated toward the cell recycle through the cell immobilization. Results Z. mobilis ZM4 and TISTR 551 were able to develop biofilms on DEAE cellulose under the differences in the morphologies. Z. mobilis ZM4 developed homogeneous biofilm that brought DEAE fiber to be crosslinking, while Z. mobilis TISTR 551 developed heterogeneous biofilm in which crosslinking was not observed. Ethanol production under batch and repeated batch...
Tipo: Journal article
Palavras-chave: Biofilm; Ethanol production; Rice bran; Zymomonas mobilis.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300009

Complement dependent cytotoxicity activity of therapeutic antibody fragments is acquired by immunogenic glycan coupling
Provedor de dados: Electronic Journal of Biotechnology
Autores: Courtois,Anthony; Gac-Breton,Stéphanie; Berthou,Christian; Guézennec,Jean; Bordron,Anne; Boisset,Claire.
Oligosaccharides are implicated in the development of the immune response notably in complement activation. Anti-tumoural immunotherapy by monoclonal antibodies (mAbs) offers some advantages to chemotherapy including cell targeting but some of them are inefficient to generate cytotoxicity dependent complement (CDC) known to be important in the antibody&amp;#146;s efficacy. The aim of this study is to give a CDC activity of mAb by linkage of a complement activating oligosaccharide to this antibody via a hetero-bifunctional linker allowing control of the conjugation reaction. We worked on non Hodgkin Burkitt&amp;#146;s lymphoma as cancer source, Fab fragments of rituximab devoid of complement activity as mAb and the trisaccharide...
Tipo: Journal article
Palavras-chave: Complement system Gala(1&amp;rarr; 3)Gal epitope immunogenic oligosaccharide immunotherapy non-Hodgkin lymphoma xenoantigen.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500005

Photo-fermentational hydrogen production of Rhodobacter sp. KKU-PS1 isolated from an UASB reactor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Assawamongkholsiri,Thitirut; Reungsang,Alissara.
Background In this study, the detection of nifH and nifD by a polymerase chain reaction assay was used to screen the potential photosynthetic bacteria capable of producing hydrogen from five different environmental sources. Efficiency of photo-hydrogen production is highly dependent on the culture conditions. Initial pH, temperature and illumination intensity were optimized for maximal hydrogen production using response surface methodology with central composite design. Results Rhodobacter sp. KKU-PS1 (GenBank Accession No. KC478552) was isolated from the methane fermentation broth of an UASB reactor. Malic acid was the favored carbon source while Na-glutamate was the best nitrogen source. The optimum conditions for simultaneously maximizing the cumulative...
Tipo: Journal article
Palavras-chave: NifD; NifH; Photo fermentation; Purple-non-sulfur bacteria.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300013

Plant genomic instability detected by microsatellite-primers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Leroy,Xavier J.; Leon,Karine; Branchard,Michel.
This report describes a new application of the Inter-Simple Sequence Repeat (ISSR) technique. This technology based on the amplification of regions between microsatellites was applied to different calli from the same cauliflower mother plant. One of the tested ISSR primers, (GATA)4, generated great polymorphism. Twelve different markers were detected on polyacrylamide gels. After sequencing, one sequence showed homology with a predicated A. thaliana gene closely related to genes involved in the regulation of cell proliferation in mammalians. This marker is characterised by three microsatellites and a palindromic sequence. Possible causes of mutations in this marker are discussed and will be investigated. ISSR amplification appears as a reliable method in...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000200005

Indole acetic acid and ACC deaminase from endophytic bacteria improves the growth of Solarium lycopersicum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Latif Khan,Abdul; Ahmed Halo,Boshra; Elyassi,Ali; Ali,Sajid; Al-Hosni,Khadija; Hussain,Javid; Al-Harrasi,Ahmed; Lee,In-Jung.
Background: Endophytic bacteria are ubiquitous in all plant species contributing in host plant's nutrient uptake and helping the host to improve its growth. Moringa peregrina which is a medicinal plant, growing in arid region of Arabia, was assessed for the presence of endophytic bacterial strains. Results: PCR amplification and sequencing of 16S rRNA of bacterial endophytes revealed the 5 endophytic bacteria, in which 2 strains were from Sphingomonas sp.; 2 strains from Bacillus sp. and 1 from Methylobacterium genus. Among the endophytic bacterial strains, a strain of Bacillus subtilis LK14 has shown significant prospects in phosphate solubilization (clearing zone of 56.71 mm after 5 d), ACC deaminase (448.3 ± 2.91 nM &amp;#945;-ketobutyrate mg-1 h-1) and...
Tipo: Journal article
Palavras-chave: ACC deaminase; Bacillus subtilis LK14; Endophytism; Indole 3-acetic acid; Tomato plant growth.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300007

A phage display combined with DNA affinity magnetic system can be applied to a screening of DNA binding proteins, such as transcription factors
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yulita,Kusumadewi Sri; Kouno,Takafumi; Ezaki,Bunichi.
Here we introduce a new approach for the screening of DNA binding proteins, using a phage library based on a phage display technique. In principal, a complementary DNA (cDNA) library based on the recombinant bacteriophage T7 expressing target proteins on its capsid (phage display) is constructed. These phage particles are hybridized with a biotinylated target DNA fragment which is immobilized on the surface of streptavidin paramagnetic particle (SA-PMP). The phage particles are released from the target DNA fragment by a nuclease treatment and the recovered phages are used to the next round of hybridization. These processes are repeated three times to amplify the target phages in the population. This simple method is faster, and more systemic than other...
Tipo: Journal article
Palavras-chave: AtGST11 gene; Biopanning; DNA binding proteins; T7 phage differential display; Transcription factors.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100014

A C1069G SNP of the MC4R gene and its association with economic traits in Korean native cattle (brown, brindle, and black)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lee,Youngsub; Park,Sairom; Kim,Hun; Lee,Seung Kyu; Kim,Jin Woo; Lee,Hak Kyo; Jeong,Dong Kee; Lee,Sung Jin.
Background: The melanocortin-4 receptor gene (MC4R) plays an important role in regulating food intake and body weight in mammals. In the present study, we identified the MC4R gene in native Korean brown, brindle, and black cattle by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP), and investigated its association with economic traits. A total of 413 cattle from the three breeds were tested for backfat thickness, carcass weight, longissimus muscle area, and marbling score, and statistical data were analyzed using the SAS program. Results: The C allele had the highest frequency in brown and brindle cattle, and the G allele frequency was highest in black cattle. The C1069G SNP was significantly (p &lt; 0.05) associated with only...
Tipo: Journal article
Palavras-chave: Economic trait; Marbling scores; MC4R gene; PCR-RFLP; SNP.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500014

Immunological strategy for detecting the pro-inflammatory cytokine TNF-alpha in salmonids
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rojas,Verónica; Morales-Lange,Byron; Guzmán,Fanny; Gallardo,José A; Mercado,Luis.
Background: Tumour necrosis factor-alpha (TNF-&amp;#945;) is a pro-inflammatory cytokine which exerts a variety of immunological functions in vertebrates. TNF-&amp;#945; has been identified and cloned in a number of teleost fish species; nevertheless, the functions displayed by this cytokine in fishes remain poorly understood, given that the low sequence identity compared to their mammalian counterpart, limit fish TNF-&amp;#945; detection using mammalian antibodies. Then, for fish immune response characterization is fundamental the production of specific fish anti-TNF-&amp;#945; antibody. Results: We have developed a monoespecific antibody against the pro-inflammatory molecule TNF-&amp;#945; of salmonid fish. TNF-&amp;#945; epitope region was identified...
Tipo: Journal article
Palavras-chave: Fish immunity; Salmonid immunity; TNF-alpha antibody.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500021

Effects of agitation and exogenous H2 on bioconversion of sugarcane bagasse into ethanol by Clostridium thermocellum ATCC 27405
Provedor de dados: Electronic Journal of Biotechnology
Autores: Groposo,Claudia; Castro,Aline Machado de; Pereira Jr,Nei.
Background: The production of ethanol by a Consolidated Bioprocessing (CBP) strategy, which simultaneously combines cellulase production, lignocellulosic biomass hydrolysis and fermentation of released sugars to ethanol in one bioreactor, is a promising technology for cost reduction in the biological processing of biomass, specially using agroindustrial residues. Clostridium thermocellum is an anaerobic, thermophilic, strictly fermentative gram positive bacterium that meets all the requirements for CBP. Results: Ethanol concentration obtained in the non-stirred fermentation process in flasks with raw bagasse was two times greater than that in the stirred system. The results observed using a pretreated sugarcane bagasse in non-stirred flasks regarding...
Tipo: Journal article
Palavras-chave: Consolidated bioprocessing; Pretreated sugarcane bagasse; Raw sugarcane bagasse; Thermophilic.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600009

Population structure and genetic diversity of Brazilian popcorn germplasm inferred by microsatellite markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: da Silva,Tereza Aparecida; Belizário Cantagalli,Liriana; Saavedra,Javier; Lopes,Ana Daniela; Aparecida Mangolin,Claudete; Pires da Silva Machado,Maria de Fatima; Scapim,Carlos Alberto.
Background The genetic diversity and structure of 31 popcorn accessions of the germplasm bank of the State University of Maringá were assessed using 30 microsatellite primers. Results 127 alleles were identified from 30 evaluated loci. The number of alleles per locus ranged from two to eight. The overall mean of the polymorphic loci averaged 79.89%. The primers UMC1549 and UMC1072 detected polymorphism in all accessions analyzed. The mean observed heterozygosity ranged from 0.07 to 0.30 and the highest proportion of heterozygous plants was observed in accession BOZM 260 (Ho = 0.30). The analysis of molecular variance revealed that 60% of the total genetic variation was found within accessions and 40% was found between accessions. The Bayesian clustering...
Tipo: Journal article
Palavras-chave: Genetic variability; Maize; Molecular marker.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300007

Phytoconstituents and antioxidant properties among commercial tea (Camellia sinensis L.) clones of Iran
Provedor de dados: Electronic Journal of Biotechnology
Autores: Azadi Gonbad,Reza; Afzan,Adlin; Karimi,Ehsan; Sinniah,Uma Rani; Kumara Swamy,Mallappa.
Background Tea (Camellia sinensis), a well-known beverage is consumed frequently worldwide due to its high antioxidant properties. The present study determines the amount of phytochemicals and antioxidant activities among 12 high yielding tea clones cultivated in Iran. Results Among the 12 clones studied, tea clone Iran 100 had the highest total phenolic content and total flavonoid content with values of 8.44 ± 1.03 mg gallic acid equivalents per gram dry weight and 4.50 ± 0.16 mg rutin equivalents per gram dry weight respectively. High performance Liquid Chromatography (HPLC) analysis of phenolics and flavonoids in 12 clones revealed the presence of (+)-catechin, (-)-epicatechin, (-)-epigallocatechin, (-)-epigallocatechin-gallate, (-)-epicatechingallate,...
Tipo: Journal article
Palavras-chave: Camellia sinensis; DPPH assay; Methanolic extract; Total flavonoid content; Total phenolic content.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600008

A real-time PCR genotyping assay to detect FAD2A SNPs in peanuts (Arachis hypogaea L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Barkley,Noelle A; Wang,Ming Li; Pittman,Roy N.
The high oleic (C18:1) phenotype in peanuts has been previously demonstrated to result from a homozygous recessive genotype (ol1ol1ol2ol2) in two homeologous fatty acid desaturase genes (FAD2A and FAD2B) with two key SNPs. These mutant SNPs, specifically G448A in FAD2A and 442insA in FAD2B, significantly limit the normal function of the desaturase enzyme activity which converts oleic acid into linoleic acid by the addition of a second double bond in the hydrocarbon chain. Previously, a genotyping assay was developed to detect wild type and mutant alleles in FAD2B. A real-time PCR assay has now been developed to detect wild type and mutant alleles (G448A) in FAD2A using either seed or leaf tissue. This assay was demonstrated to be applicable for the...
Tipo: Journal article
Palavras-chave: Fatty acid composition; Gas chromatography; Peanut (Arachis hypogaea L.); Real-time PCR; SNP genotyping.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100009

Purification of a functional competitive antagonist for calcitonin gene related peptide action from sardine hydrolysates
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rousseau,Marthe; Batista,Irineu; Le Gal,Yves; Fouchereau-Peron,Martine.
Calcitonin gene related peptide (CGRP) related molecules were purified from sardine hydrolysates prepared using 0.1% alcalase and two hours of hydrolysis. Gel exclusion chromatography and HPLC performed purification of these molecules. The purified molecules were characterised using specific CGRP radioimmunoassays and radioreceptoraasays. From 22 mg of crude extract, we obtained 14 µg of CGRP related molecules, the molecular weight determined by mass spectrophotometry was 6000 daltons. The biological activity of these molecules was analysed using the ability of CGRP to stimulate the adenylate cyclase activity in rat liver membranes. The purified molecules induced an inhibition of the CGRP stimulated adenylate cyclase activity, this effect was specific as...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000100003

Characterization of Dunaliella salina strains by flow cytometry: a new approach to select carotenoid hyperproducing strains
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mendoza,Héctor; de la Jara,Adelina; Freijanes,Karen; Carmona,Laura; Ramos,Ana Alexandra; de Sousa Duarte,Vanessa; Serafim Varela,João Carlos.
In the present work the characterization of different strains of Dunaliella salina from established cell culture collections and various isolates from solar saltworks located in the Canary Island, as well as one mutant, was carried out in order to assess the existence of intraspecific differences and to determine the potential productivity of each one. Morphological characteristics such as cellular size and cellular complexity and parameters linked to cellular physiology, such as pigment content or cellular growth rate, were determined by means of traditional techniques as well as flow cytometry. Results showed a high morphological and physiological intraspecific variability among the studied strains. Results suggest that the application of the lipidic dye...
Tipo: Journal article
Palavras-chave: Carotene; Carotenogenesis; Dunaliella salina; Flow cytometry; Nile red.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400005

Isolation, purification, and characterization of L-glutamate oxidase from Streptomyces sp. 18G
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wachiratianchai,Supawadee; Bhumiratana,Amaret; Udomsopagit,Suchat.
An extracellular L-glutamate oxidase (GLOD) was purified from soil-isolated Streptomyces sp 18G. The enzyme had a molecular weight of approximately 120,000 and consisted of two identical subunits, each with a molecular weight of 61,000. The isoelectric point was pH 8.5 and the enzyme had an optimal pH between 7.0-7.4. GLOD showed the maximum activity at 37ºC. The GLOD activity was stable at pH ranging from 6.5 to 7.0 for 1 hr. Among 21 amino acids tested for substrate specificity, L-glutamate was almost exclusively oxidized. D-glutamate and L-aspartate were oxidized but only to extents of 0.79% and 0.53%, respectively.
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300009

Rigor: The essence of scientific work
Provedor de dados: Electronic Journal of Biotechnology
Autores: Allende,Jorge E.
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000100001

Physicochemical and nutritional alterations induced by two-spotted spider mite infestation on strawberry plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Livinali,Emanuele; Sperotto,Raul Antonio; Ferla,Noeli Juarez; Souza,Claucia Fernanda Volken de.
Background Strawberry is a pseudofruit mainly cultivated in temperate climate regions. Considering its high levels of ascorbic acid and phenolic compounds, the consumption of strawberry fruit can be beneficial to health. The Brazilian strawberry production revolves around 3000 tons per year, significantly influencing the food market and generating income to farmers. However, this production can be partially impaired by two-spotted spider mite (TSSM) Tetranychus urticae Koch infestations, due to decreases in the quality and quantity of fruit. Since there are no data in the literature about alterations caused by TSSM infestation in strawberry plants, our work aimed towards evaluating nutritional and physicochemical parameters of TSSM-infested strawberry...
Tipo: Journal article
Palavras-chave: Biological control; Phytoseiulus macropilis; Tetranychus urticae.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000500001

Preparation and characterization of &amp;#954;-carrageenase immobilized onto magnetic iron oxide nanoparticles
Provedor de dados: Electronic Journal of Biotechnology
Autores: Xiao,Anfeng; Xu,Caiyun; Lin,Yan; Ni,Hui; Zhu,Yanbing; Cai,Huinong.
Background Carboxyl-functionalized magnetic nanoparticles were synthesized via chemical co-precipitation method and modified with oleic acid which was oxidized by potassium permanganate, and &amp;#954;-carrageenase from Pseudoalteromonas sp. ASY5 was subsequently immobilized onto them. The immobilization conditions were further optimized, and the characterizations of the immobilized &amp;#954;-carrageenase were investigated. Results The &amp;#954;-carrageenase was immobilized onto magnetic iron oxide nanoparticles, and the bonding was verified by Fourier transform infrared spectroscopy. The optimal conditions for &amp;#954;-carrageenase immobilization were 2.5% (w/v) glutaraldehyde, 13.9 U &amp;#954;-carrageenase for 20 mg of magnetic nanoparticles, a 2-h...
Tipo: Journal article
Palavras-chave: Carrageenase; Characterization; Immobilization; Nanoparticles.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000100001

Production of enzymes from Lichtheimia ramosa using Brazilian savannah fruit wastes as substrate on solid state bioprocessess
Provedor de dados: Electronic Journal of Biotechnology
Autores: Silva,Cinthia Aparecida de Andrade; Lacerda,Maria Priscila Franco; Leite,Rodrigo Simões Ribeiro; Fonseca,Gustavo Graciano.
Background: Enzyme production by solid state bioprocess (SSB) using residues as substrate for microorganisms is an alternative for costs reduction and to avoid their disposal into environment. The aim of this work was to evaluate the physiology of the fungus Lichtheimia ramosa in terms of microbial growth and production of amylases, &amp;#946;-glucosidases, carboxymethylcellulase (CMCase), and xylanases, via SSB, utilizing wastes of the Brazilian savannah fruits bocaiuva (Acrocomia aculeata), guavira (Campomanesia pubescens) and pequi (Caryocar brasiliense) as substrate at different temperatures (25, 30, and 35ºC) during 168 hrs. Results: Samples were taken every 24 hrs, which resulted in 8-points kinetic experiments to determine microbiological and...
Tipo: Journal article
Palavras-chave: Amylase &amp;#946; -glucosidase CMCase Lichtheimia ramosa xylanase.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500009

Optimization of fermentation conditions for pristinamycin production by immobilized Streptomyces pristinaespiralis using response surface methodology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Li-Jing; Zheng,Â· Xi; Jin,Â· Zhi-Hua; Hu,Â· Sheng; He,Â· Mei-Ru.
Response surface methodology was used to optimize the fermentation conditions for the production of pristinamycin by immobilization of Streptomyces pristinaespiralis F213 in shaking &amp;#64258;ask cultivation. Seed medium volume, fermentation medium volume and shaking speed of seed culture were found to have signi&amp;#64257;cant effects on pristinamycin production by the Plackett-Burman design. The steepest ascent method was adopted to approach the vicinity of optimum space, followed by central composite design for further optimization. A quadratic model was built to &amp;#64257;t the pristinamycin production. The optimum conditions were found to be seed medium volume of 29.5 ml, fermentation medium volume of 28.8 ml, and shaking speed of seed culture at...
Tipo: Journal article
Palavras-chave: Fermentation conditions; Immobilization; Pristinamycin; Response surface methodology; Streptomyces pristinaespiralis.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000400006

Molecular cloning and antibacterial activity of hepcidin from Chinese rare minnow (Gobiocypris rarus)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ke,Fei; Wang,Yun; Yang,Chuan-Shun; Xu,Chen.
Background Hepcidins, a kind of cysteine-rich antimicrobial peptides, play important roles in host immunological processes and iron regulation, which have been identified from several fish species. The rare minnow (Gobiocypris rarus), an endemic cyprinid fish in China, has been used extensively as model animal in laboratory. However, little is known about its hepcidin. Here, we report the cloning and characterization of a hepcidin gene from the liver of Chinese rare minnow. Results The full-length cDNA of rare minnow hepcidin is 662 bp, which contains an ORF of 273 bp encoding a prepropeptide of 90 amino acid residues. The predicted prepropeptide contains three domains: a signal peptide of 24 amino acids, a prodomain of 41 amino acids, and a mature peptide...
Tipo: Journal article
Palavras-chave: Cysteine residues; Phylogenetic analysis; Rare minnow hepcidin; Synthetic peptide.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300005

Effect of sulphate concentration and sulphide desorption on the combined removal of organic matter and sulphate from wastewaters using expanded granular sludge bed (EGSB) reactors
Provedor de dados: Electronic Journal of Biotechnology
Autores: Valdés,Freddy; Muñoz,Edmundo; Chamy,Rolando; Ruiz,Gonzalo; Vergara,Christian; Jeison,David.
During the application of anaerobic processes to high sulphate concentration wastewaters, operational problems are expected due to the occurrence of sulphate reduction. Sulphide production reduces effluent quality and may produce inhibition. The application of Expanded Granular Sludge Bed (EGSB) reactors for the combined removal of organic matter and sulphate was studied at different COD/sulphate and 3 values of pH. During the EGSB reactor operation, most of the sulphide remains in the liquid phase reducing effluent quality. The inclusion of a desorption column in the recirculation of the EGSB reactor promotes mass transfer to the gas phase, reducing the sulphide concentration in the liquid phase, significantly decreasing the chemical oxygen demand of the...
Tipo: Journal article
Palavras-chave: Anaerobic digestion; EGSB; Sulphate reduction; Sulphide.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400004

VNTR-based diversity analysis of 2x and 4x full-sib Musa hybrids
Provedor de dados: Electronic Journal of Biotechnology
The triploid plantain landrace Obino l’Ewai (Musa spp., AAB genome) has been crossed with a wild diploid banana (M. acuminata subsp. burmannica var. ‘Calcutta 4’, AA genome) to generate full-sib diploid and tetraploid hybrids combining good agronomic performance and disease resistance. Microsatellite marker analysis of the parental genotypes confirmed the highly heterozygous nature of both parental genotypes. Comparative analysis of 2x and 4x full-sib hybrids with their parental genotypes indicated that tetraploid hybrids are generally more closely related to Obino l’Ewai than their diploid full-sibs. Based on VNTR analysis it is possible to identify those hybrids, which may be most useful in subsequent breeding of secondary triploid hybrids. There was a...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000300002

Analysis of genetic and epigenetic variation in in vitro propagated potato somatic hybrid by AFLP and MSAP marker
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tiwari,Jagesh Kumar; Saurabh,Shaumaya; Chandel,Poonam; Singh,Bir Pal; Bhardwaj,Vinay.
Background: Genetic and epigenetic changes (DNA methylation) were examined in the tissue-culture propagated interspecific potato somatic hybrids between dihaploid Solanum tuberosum and S. pinnatisectum. Amplified fragment length polymorphism (AFLP) and methylation-sensitive amplified polymorphism (MSAP) were applied to detect the genetic and epigenetic changes, respectively in the somatic hybrids mother plants (1st cycle) and their regenerants (30th cycles sub-cultured). Results: To detect genetic changes, eight AFLP primer combinations yielded a total of 329 scorable bands of which 49 bands were polymorphic in both mother plants and regenerants. None of the scorable bands were observed in term of loss of original band of mother plant or gain of novel band...
Tipo: Journal article
Palavras-chave: AFLP; DNA methylation; In vitro propagation; MSAP; Potato; Somatic hybrids.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600005

Agrobacterium rhizogenes mediated genetic transformation resulting in hairy root formation is enhanced by ultrasonication and acetosyringone treatment
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kumar,Vinod; Sharma,Ashwani; Narasimha Prasad,Bellur Chayapathy; Bhaskar Gururaj,Harishchandra; Aswathanarayana Ravishankar,Gokare.
The phytopathogenic bacteria Agrobacterium rhizogenes genetically transforms plants by transferring a portion of the resident Ri plasmid, the T-DNA to the plant. Plant species differ in their temporal competence for transformation. But various physical and chemical methods are found to enhance transformation frequency. Agrobacterium rhizogenes mediated transformation efficiency was assessed under the influence of sonication, calcium treatment, acetosyringone and macerating enzymes in suitable combinations in Nicotiana tabacum as a model system. Manual wounding resulted in 21% transformation frequency. Where as sonication resulted in 2.2 fold increase, followed by sonication with CaCl2 treatment resulted in 2.5 fold increase and sonication with...
Tipo: Journal article
Palavras-chave: Agrobacterium rhizogenes; Hairy roots; Nicotiana tabacum; Transformation frequency; Ultra-sonication.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400002

Genetic and physical map of broad host range cosmid pRG930cm
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chibeu,Andrew; Lavigne,Rob; Mattheus,Wesley; Matthijs,Sandra; Cornelis,Pierre; Volckaert,Guido.
We hereby present the complete sequence and annotation of pRG930cm, a spectinomycin/streptomycin/chloramphenicol-resistant cosmid vector. pRG930cm (17,256 bp; GenBank Accession No.: FM174471) has a broad host range, and is stably maintained by a number of Gram-negative bacteria including Pseudomonas spp, Escherichia coli, Agrobacterium tumefaciens and Azorhizobium caulinodans ORS571. pRG930cm is already widely used and its sequence will aid efficient construction and analysis of cosmid libraries.
Tipo: Journal article
Palavras-chave: Cosmid; PRG930cm; Pseudomonas; Sequencing.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200010

Selection of sulfur oxidizing bacterium for sulfide removal in sulfate rich wastewater to enhance biogas production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kantachote,Duangporn; Charernjiratrakul,Wilawan; Noparatnaraporn,Napavarn; Oda,Kohei.
Sulfur oxidizing bacteria (SOB) were isolated and tested in order to remove sulfide from high sulfate wastewater to reduce the amount of hydrogen sulfide (H2S) in the produced biogas. A promising SOB isolate, designated as isolate T307, was selected due to its best sulfide removal (86.7%) in the effluent of a sulfate reduction reactor (SRR) over a 24 hrs incubation. The bacterium was able to grow better as a mixotroph (yeast extract as a carbon source) than as a chemolithoautotroph. In addition, as a heterotroph, the bacterium grew well with yeast extract and peptone. Based on partial 16S rRNA gene sequence, the isolated T307 was an Alcaligenes sp. and was able to convert most of sulfide species (total sulfide: TS; dissolved sulfide: DS and H2S) into...
Tipo: Journal article
Palavras-chave: Biodesulfurization; Biogas; Effluent from a sulfate reduction reactor; Sulfide.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200013

A nationwide biotechnology outreach and awareness program for Malaysian high schools
Provedor de dados: Electronic Journal of Biotechnology
Autores: Firdaus-Raih,Mohd; Senafi,Sahidan; Munir Murad,Abdul; Marzuki Sidik,Nik; Kiew Lian,Wan; Daud,Fauzi; Zainal Ariffin,Shahrul Hisham; Zamrod,Zulkeflie; Chon Seng,Tan; Sofiman Othman,Ahmad; Azni Harmin,Sharr; Radzuan Saad,Mohd Yusof; Mohamed,Rahmah.
Biotechnology education in developing nations remains one of the rate limiting factors in achieving optimal human resource capacity to drive and tap the bio-resources of these nations. Many developing countries are situated within rich bio-diversity enclaves. Biotechnology offers the promise of tapping these bio resources towards due process of developing these nations. While there may be a steady stream of biology and biotechnology based graduates, from Malaysian as well as foreign universities contributing to the human resource base for these countries, the numbers and knowledge diversity produced, still lack the capacity to optimally power research and development as well as supply the industrial biotechnology sectors of these countries. Realizing the...
Tipo: Journal article
Palavras-chave: Biotechnology awareness; Biotechnology education; Capacity building.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100004

Meiotic study of Zea mays ssp. mays (2n = 40) x Tripsacum dactyloides (2 n = 72) hybrid and its progeny
Provedor de dados: Electronic Journal of Biotechnology
Autores: Molina,María del Carmen; García,María Dina; Chorzempa,Silvia Elena.
Maize (2n = 40) x Tripsacum dactyloides (2n = 72) F1 hybrid plants (2n = 56) were obtained by embryo rescue and induction of somatic embryogenesis/organogenesis. Hybrid plants showed Tripsacum-like phenotypes, tolerance to stresses such as NaCl salinity and low temperatures. The more frequent meiotic configurations were 28II (24%), 24II + 2IV (19%) and 26II + 1IV (12%), with an average per cell of 0.55I + 25.18II + 1.19IV. Significant differences between plants were not observed. Pollen fertility ranged from 0% to 50%. After pollination with maize or Tripsacum, 20% of F1 plants have developed viable seeds, which originated the progeny. Thirty five percent of the progeny showed 2n = 56 chromosomes and F1 like-phenotypes, which suggests they have apomictic...
Tipo: Journal article
Palavras-chave: Chromosome number; Corn; Eastern gamagrass; Remote hybridisation.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300020

Enhancing production of lipase MAS1 from marine Streptomyces sp. strain in Pichia pastoris by chaperones co-expression
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lan,Dongming; Qu,Man; Yang,Bo; Wang,Yonghua.
Background: A thermostable lipase MAS1 from marine Streptomyces sp. strain was considered as a potential biocatalyst for industrial application, but its production level was relatively low. Here, the effect of chaperones co-expression on the secretory expression of lipase MAS1 in Pichia pastoris was investigated. Result: Co-expression of protein disulfide isomerase (PDI), HAC1 and immunoglobulin binding protein could increase the expression level of lipase MAS1, whereas co-expression of Vitreoscilla hemoglobin showed a negative effect to the lipase MAS1 production. Among them, PDI co-expression increased lipase MAS1 expression level by 1.7-fold compared to the control strain harboring only the MAS1 gene. Furthermore, optimizing production of lipase MAS1...
Tipo: Journal article
Palavras-chave: Fermentation optimization; Methanol fed-batch; Protein disulfide isomerase; Vitreoscilla hemoglobin.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400009

Evidence of a role for prolactin as regulators of ovarian follicular development in goose
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ma,Rong; Jiang,Dongmei; Chen,Ziyu; Kang,Bo.
Background Prolactin (PRL) regulates development and reproduction, and its effects are mediated by the prolactin receptor (PRLR). In order to clarify the role of PRLR and PRL in the process of follicular development in the goose ovary, the level of PRLR mRNA expression in the ovary and follicles of the Sichuan white goose was determined, as well as the PRL concentration in ovarian follicles. Results The level of PRLR mRNA in the hierarchical follicles (HFs) initially increased, and subsequently decreased, whereas PRLR expression was initially low and later increased in postovulatory follicles (POFs). The level of PRLR mRNA expression was the highest in the F4 follicles, and lowest in the F1 follicles in all of the examined follicles. Compared with the...
Tipo: Journal article
Palavras-chave: Postovulatory follicle; Preovulatory follicle; Prolactin receptor; Prolactin; Sichuan white goose.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600001

Antibacterial activity of the Antarctic bacterium Janthinobacterium sp: SMN 33.6 against multi-resistant Gram-negative bacteria
Provedor de dados: Electronic Journal of Biotechnology
Autores: Asencio,Geraldine; Lavin,Paris; Alegría,Karen; Domínguez,Mariana; Bello,Helia; González-Rocha,Gerardo; González-Aravena,Marcelo.
Background The increment of resistant strains to commonly used antibiotics in clinical practices places in evidence the urgent need to search for new compounds with antibacterial activity. The adaptations that Antarctic microorganisms have developed, due to the extreme environment that they inhabit, promote them as a potential new source of active compounds for the control of microorganisms causing infections associated with health care. The aim of this study was to evaluate the antibacterial activity of an ethanol extract of the Antarctic bacterium Janthinobacterium sp., strain SMN 33.6, against nosocomial multi-resistant Gram-negative bacteria. Results Inhibitory activity against human Gram-negative bacterial pathogens, with concentrations that varied...
Tipo: Journal article
Palavras-chave: Antarctica; Antimicrobial; Antibiotic resistance; Bacterial pigment.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100001

Effects of temperature, pH and additives on the activity of tannase produced by Paecilomyces variotii
Provedor de dados: Electronic Journal of Biotechnology
Autores: Battestin,Vania; Macedo,Gabriela A.
A biochemical characterization of the tannase from a Paecilomyces variotii strain isolated in São Paulo, Brazil was carried out. Paecilomyces variotii is a strain obtained from the screening of five hundred fungi that were tested for their production of tannase. The enzyme produced was partially purified using ammonium sulfate precipitation followed by ion exchange chromatography, diethylaminoethyl (DEAE)-Sepharose. Effects of temperature and pH on the activity of crude tannase crude and purified tannase was studied. Km was found to be 0.61 µmol and Vmax = 0.55 U/mL. Temperature of 40 to 65ºC and pH 4.5 to 6.5 were optimum for tannase activity and stability; it could find potential use in the food-processing industry. The effects of different inhibitors,...
Tipo: Journal article
Palavras-chave: Characterization enzyme fermentation fungi Paecilomyces variotii; Tannase.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200003

Academic Manpower Training Policy in Israel in the Area of Biotechnology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Herskovic,Shlomo.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200003

DNA removal from a purification process of recombinant hepatitis B surface antigen
Provedor de dados: Electronic Journal of Biotechnology
Autores: Beldarraín Iznaga,Alejandro; Candelario Frontera,Mayda; Rodríguez Uramis,Javier; Tejera González,José Blas; Calvo Parra,Yodelis; Madruga González,Yoel.
We studied the capacity of an API-rHBsAg purification process to eliminate DNA contamination from yeast-host cell. Firstly, was demonstrated consistency of manufacturing purification process to remove DNA, from (3.9 ± 1.9)10(8) pg/dose in starting material to (3.4 ± 1.6) pg/dose, equivalent to 8.2 log in Active Pharmaceutical Ingredient (API), measuring DNA quantity in several unit operations along manufacturing process for twenty batches, five consecutive in 2000, 2001, 2003 and 2005. These values for API, lower than 10 pg/dose, accomplish current WHO requirements for Hepatitis B vaccines obtaining by recombinant DNA technology (&lt;a href="#36"&gt;WHO, 1989&lt;/a&gt;; &lt;a href="#3"&gt;European Pharmacopoeia, 2001a&lt;/a&gt;). The main removal factor...
Tipo: Journal article
Palavras-chave: DNA-clearance factor; Process characterization; RHBsAg purification process; Spiking experiments.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100004

Technological Strategies of Successful Latin American Biotechnological Firms
Provedor de dados: Electronic Journal of Biotechnology
This paper presents the results of the analysis of the technological strategies of eight Latin American biotech firms. There is little literature on strategies of follower firms in developing countries in high-technology sectors. For that reason, the authors undertook case studies of firms of six countries of Latin America that share the characteristics of being successful in the market place while adopting technology-follower strategies. The analysis considers five dimensions that, according to the literature on the management of technology, constitute the basic benchmarks of the strategy. These dimensions include innovating activities of the firm to improve, its position on the market; orientation of research and dominant technological goals; technology...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000100002

Heavy metal uptake by agro based waste materials
Provedor de dados: Electronic Journal of Biotechnology
Autores: Qaiser,Suleman; Saleemi,Anwar R; Mahmood Ahmad,Muhammad.
Presence of heavy metals in the aquatic systems has become a serious problem. As a result, there has been a great deal of attention given to new technologies for removal of heavy metal ions from contaminated waters. Biosorption is one such emerging technology which utilized naturally occurring waste materials to sequester heavy metals from industrial wastewater. The aim of the present study was to utilize the locally available agricultural waste materials for heavy metal removal from industrial wastewater. The wastewater containing lead and hexavalent chromium was treated with biomass prepared from ficus religiosa leaves. It was fund that a time of one hr was sufficient for sorption to attain equilibrium. The equilibrium sorption capacity after one hr was...
Tipo: Journal article
Palavras-chave: Biosorption; Ficus religiosa leaves; Hexavalent chromium; Kinetics; Lead; Wastewater.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300008

Expression of SOD transgene in pepper confer stress tolerance and improve shoot regeneration
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chatzidimitriadou,Kiriaki; Nianiou-Obeidat,Irini; Madesis,Panagiotis; Perl-Treves,Rafael; Tsaftaris,Athanasios.
The objective of this work was to study the stress tolerance and regeneration capability of transgenic pepper plants carrying a sod gene, encoding a tomato chloroplast-localized Cu/Zn SOD protein. The expression of the sod gene was confirmed by enzymatic staining following polyacrylamide gel electrophoresis (PAGE), revealing a &amp;#8216;novel&amp;#8217; band, which could represent a heterodimeric enzyme. Transgenic T1 and T2 progeny plants were exposed to different oxidative stresses including Methyl viologen (MV) and drought and found to have an increased resistance to oxidative damage. Furthermore, the SOD carrying transgenic pepper plants showed increased levels of regeneration efficiency compared to the wild type pepper plants. Pepper is a...
Tipo: Journal article
Palavras-chave: Capsicum annum L.; Drought stress; MV; Regeneration; SOD.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400007

Transformation of high concentrations of chlorophenols by the white-rot basidiomycete Trametes versicolor immobilized on nylon mesh
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sedarati,Mohammad R; Keshavarz,Tajalli; Leontievsky,Alexey A; Evans,Christine S.
Free-cell cultures of Trametes versicolor were compared with cultures immobilized on nylon mesh in a 2-litre bioreactor for transformation of pentachlorophenol (PCP) and 2,4-dichlorophenol (2,4-DCP), added at intervals to the liquid culture medium over a period of 816 hrs. Increasing amounts of PCP from 200 ppm to 2000 ppm added batchwise to cultures permitted acclimatization of the fungus to these toxic pollutants. A total addition of 2000 ppm of 2,4-DCP and 3400 ppm PCP were removed from the immobilized cultures with 85% of 2,4-DCP and 70% of PCP transformed by enzymes (laccase and Mn-peroxidase), 5% 2,4-DCP and 28% PCP adsorbed by the biomass and 10% 2,4-DCP and 2% PCP retained in the medium at the termination of the fermentation after 1020 hrs. In...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000200005

Silanol - A novel class of antimicrobial agent
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kim,Yun-mi; Farrah,Samuel; Baney,Ronald H.
Recently, a significant amount of attention has been directed toward development of novel classes of biocides because of the potential for microbial contamination and infection risks to military personnel and in the general population. We have recently discovered a new and unexpected class of powerful biocides based upon compounds derived through simple chemistry from silicone intermediates, "silicon alcohols" called, silanols. One example is trialkylsilanols, R3SiOH. Antimicrobial tests were carried out against Gram-negative bacterium, Escherichia coli, and Gram-positive, Staphylococcus aureus, with silanols, t-butanol, and siloxanes. Trialkylsilanols were very effective biocides against Escherichia coli and Staphylococcus aureus. The number of viable...
Tipo: Journal article
Palavras-chave: Antimicrobial agents; Bacteria; Biocide; Silanols.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200012

Prodigiosin found in Serratia marcescens y2 initiates phototoxicity in the cytomembrane
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Fei; Luo,Hailan; Song,Guohua; Liu,Chang; Wang,Jianguo; Xu,Jingliang; Su,Xiuhong; Ma,Xu Yuan.
Background: Light can be absorbed by bacterial pigment and affects its growth. Prodigiosin is a red pigment found in various bacterial species. The purpose of this study was to investigate the impacts of light on prodigiosin production, biomass formation, and membrane integrity of Serratia marcescens y2. Results: S. marcescens y2 grew better and produced more intracellular prodigiosin in darkness than in illumination. The pigment leakage ratio from cells was detected more in light than in darkness conditions. Ethidium bromide uptake assay could visually prove the prodigiosin-related loss of membrane integrity under illumination. A higher concentration of malondialdehyde (MDA) was detected in light-treated culture than in darkness. Tests of different light...
Tipo: Journal article
Palavras-chave: Ethidium bromide; Homogeneous light; Malondialdehyde; Red pigment.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400007

Development and application of high-throughput amplified fragment length polymorphism technique in Calluna vulgaris (Ericaceae)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Borchert,Thomas; Gawenda,Inka.
Calluna vulgaris is an important ornamental crop of the horticultural industry in Europe. In order to improve breeding of this species, especially of the most important trait of &amp;#8216;bud-flowering', the implementation of molecular techniques that allow rapid, reproducible and efficient screening of whole segregating populations e.g. for molecular marker and mapping approaches is a requirement. We therefore aimed to introduce the powerful tool of amplified fragment length polymorphisms (AFLP®), a widely and successfully applied method, into our methodological assortment. As an essential prerequisite, the isolated DNA should be of adequate quality which is a common obstacle when dealing with woody species and their interfering secondary...
Tipo: Journal article
Palavras-chave: DNA content; Mapping; Marker-assisted selection; Ornamental; Plant tissue.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000200007

Medium-term and long-term in vitro conservation and safe international exchange of yam (Dioscorea spp.) germplasm
Provedor de dados: Electronic Journal of Biotechnology
Autores: Malaurie,Bernard; Trouslot,Marie-France; Berthaud,Julien; Bousalem,Mustapha; Pinel,Agnès; Dubern,Jean.
Yam edible tubers feed million of peoples in the intertropical area, where they represent 12% of human feeding. However, as a vegetatively propagated crop, yam is seriously affected by an accumulation of pathogens. Establishing in vitro germplasm collection is a process that cleans the plants from all diseases but viruses. It gives a good control on the preservation of the yam genetic resources and facilitates international exchanges of healthy plant material. Two kinds of in vitro germplasm preservation were considered : slow growth condition culture for mid-term preservation, and cryopreservation using the encapsulation/dehydration technique for long-term preservation. Virus eradication was approached by meristem culture and chemo and thermotherapy....
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000300001

Insect resistance and risk assessment studies of advanced generations of basmati rice expressing two genes of Bacillus thuringiensis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rahman,Mahmood-ur; Rashid,Hamza; Shahid,Ahmad Ali; Bashir,Khurram; Husnain,Tayyab; Riazuddin,Sheikh.
Advanced generations of different transgenic lines of indica basmati rice (Basmati-370) expressing two unrelated Bt genes, cry1Ac and cry2A were evaluated for resistance to Yellow Stem Borer (YSB) and Rice Leaf Folder (RLF) under field conditions compared to control lines over three years (2003-2005). Homozygous lines were selected and analyzed for insect resistance, morphological, physiochemical properties and risk assessment studies. After artificial infestation of target insects, the transgenic plants showed significant resistance. Data were recorded in terms of dead hearts and white heads at vegetative and flowering stage respectively. Transgenic lines showed up to 100 and 96% resistance against yellow stem borer at vegetative and flowering stages,...
Tipo: Journal article
Palavras-chave: Bio-safety; Cry1Ac; Cry2A; Gene flow; Field trials; Gene pyramiding; Insect resistance.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200008

Expression of RsMYB1 in chrysanthemum regulates key anthocyanin biosynthetic genes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Naing,Aung Htay; Ai,Trinh Ngoc; Jeon,Su Min; Park,Kyeung Il; Lim,Ki Byung; Kim,Chang Kil.
Background Several MYB genes belonging to R2R3 MYB transcription factors have been used in several plant species to enhance anthocyanin production, and have shown various expression or regulation patterns. This study focused on the effect of ectopic expression of an RsMYB1 isolated from radish (Raphanus sativa) on chrysanthemum cv. ‘Shinma'. Results The RT-PCR results confirmed that RsMYB1 regulated the expression of three key biosynthetic genes (CmF3H, CmDFR, and CmANS) that are responsible for anthocyanin production in transgenic chrysanthemum, but were not detected in the non-transgenic line. In all transgenic plants, higher expression levels of key biosynthetic genes were observed in flowers than in leaves. However, the presence of RsMYB1 in...
Tipo: Journal article
Palavras-chave: Anthocyanin; Chrysanthemum; Morphology; RT- PCR; Transcription factor.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500006

Multiple model approach to modelling of Escherichia coli fed-batch cultivation extracellular production of bacterial phytase
Provedor de dados: Electronic Journal of Biotechnology
Autores: Roeva,Olympia; Pencheva,Tania; Tzonkov,Stoyan; Arndt,Michael; Hitzmann,Bernd; Kleist,Sofia; Miksch,Gerchard; Friehs,Karl; Flaschel,Erwin.
The paper presents the implementation of multiple model approach to modelling of Escherichia coli BL21(DE3)pPhyt109 fed-batch cultivation processes for an extracellular production of bacterial phytase. Due to the complex metabolic pathways of microorganisms, the accurate modelling of bioprocesses is rather difficult. Multiple model approach is an alternative concept which helps in modelling and control of complex processes. The main idea is the development of a model based on simple submodels for the purposes of further high quality process control. The presented simulations of E. coli fed-batch cultivation show how the process could be divided into different functional states and how the model parameters could be obtained easily using genetic algorithms....
Tipo: Journal article
Palavras-chave: Genetic algorithms; Modelling; Multiple model approach.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400012

Cyclodextrin glucanotransferase immobilization onto functionalized magnetic double mesoporous core-shell silica nanospheres
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ibrahim,Abdelnasser S.S.; Al-Salamah,Ali A; El-Toni,Ahmed Mohamed; El-Tayeb,Mohamed A; Elbadawi,Yahya B.
Background Cyclodextrin glucanotransferase (CGTase) from Amphibacillus sp. NPST-10 was covalently immobilized onto amino-functionalized magnetic double mesoporous core-shell silica nanospheres (mag@d-SiO2@m-SiO2-NH2), and the properties of the immobilized enzyme were investigated. The synthesis process of the nanospheres included preparing core magnetic magnetite (Fe3O4) nanoparticles, coating the Fe3O4 with a dense silica layer, followed by further coating with functionalized or non-functionalized mesoporous silica shell. The structure of the synthesized nanospheres was characterized using TEM, XRD, and FT-IR analyses. CGTase was immobilized onto the functionalized and non-functionalized nanospheres by covalent attachment and physical adsorption. Results...
Tipo: Journal article
Palavras-chave: Amphibacillus sp; Cyclodextrin glucanotransferase; Cyclodextrins; Double mesoporous core-shell silica nanospheres; Immobilization.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000200001

Establishment of a HEK293T cell line able to site-specifically integrate and stably express GDNF by rAAV-2 vector
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Jinju; Zhang,Yun; Liu,Xiaomei; Xiang,Jingjing; Zhang,Chun.
Background: Using recombinant adeno-associated virus 2 (rAAV-2), we attempted to establish a HEK293T cell line that is able to site-specifically integrate and stably express glial cell line-derived neurotrophic factor (GDNF). Results:Recombinant vector with enhanced green fluorescent protein (EGFP) and GDNF (pTR-P5-EGFP-IRES-GDNF), as well as that carrying Rep genes and SV40 promoters (pSVAV2) were constructed and packed. HEK293T cells were co-infected with rAAV-2/EGFP-GDNF and rAAV-2/SVAV2 virus separately at 1 x 10(4),1 x 10(5),and 1x10(6) of multiplicity of infection (MOI). The efficiency of transduction was detected using flow cytometry. Additionally, the infected HEK293T cells were separately validated by touchdown polymerase chain reaction (PCR) and...
Tipo: Journal article
Palavras-chave: Glial cell line-derived neurotrophic factor; Multiplicity of infection; Recombinant adeno-associated virus 2; Site-specific integration; Transduction.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400011

Bt protein rhizosecreted from transgenic maize does not accumulate in soil
Provedor de dados: Electronic Journal of Biotechnology
Autores: Margarit,Ezequiel; Reggiardo,Martín I; Permingeat,Hugo R.
The persistence of CryIAb protein rhizosecreted in soil is important in the assessment of its environmental risk. Here we report that CryIAb protein from transgenic maize does not accumulate at high levels in soils. Levels of CryIAb protein rhizosecreted by three maize transgenic events (BT11, MON810 and 176) were studied in hydroponic cultures and found only in the MON810 and BT11 events but not in event 176 or control plants. Under field conditions, the cryIAb gene and a basal level of CryIAb protein was detected in soils from plots cultivated with transgenic and non-transgenic maize, possibly from Bacillus thuringiensis present in the soils.
Tipo: Journal article
Palavras-chave: CryIAb gene; CryIAb protein; ELISA; Genetically modified organisms; PCR; Zea mays (L.).
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200004

Bioconversion of mixed free fatty acids to poly-3-hydroxyalkanoates by Pseudomonas putida BET001 and modeling of its fermentation in shake flasks
Provedor de dados: Electronic Journal of Biotechnology
Autores: Makhdum Munawar,Khalil Munawar; Simarani,Khanom; Annuar,Mohamad Suffian Mohamad.
Background: The paper reports on the utilization of palm kernel oil (PKO) as a low cost renewable substrate for medium-chain-length poly-3-hydroxyalkanoates (mcl-PHA) production by Pseudomonas putida BET001. Investigation on the effects of selected key variables on growth, mixed free fatty acids consumption and mcl-PHA production by the bacterial culture in the shaken flask system were carried out along with its kinetic modeling. Results: The biomass production, fatty acids consumption and mcl-PHA production were found favorable when the strain was cultured in mineral medium at pH 6-7,28°C, aeration surface-to-volume ratio of 0.4 x 10(6) m-1, 250 rpm agitation rate for 48 h. Mcl-PHA production by this strain showed mixed growth and non-growth associated...
Tipo: Journal article
Palavras-chave: Biopolymer; Fermentation; Medium-chain-length PHA; Palm kernel oil; Pseudomonas putida.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000100008

Phenolic compound production and biological activities from in vitro regenerated plants of gherkin (Cucumis anguria L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Thiruvengadam,Muthu; Chung,Ill-Min.
Background The effect of polyamines (PAs) along with cytokinins (TDZ and BAP) and auxin (IBA) was induced by the multiple shoot regeneration from leaf explants of gherkin (Cucumis anguria L.). The polyphenolic content, antioxidant and antibacterial potential were studied from in vitro regenerated and in vivo plants. Results Murashige and Skoog (MS) medium supplemented with 3% sucrose containing a combination of 3.0 µM TDZ, 1.0 µM IBA and 75 µM spermidine induced maximum number of shoots (45 shoots per explant) was achieved. Regenerated shoots elongated in shoot elongation medium containing 1.5 µM GA3 and 50 µM spermine. The well-developed shoots were transferred to root induction medium containing 1.0 µM IBA and 50 µM putrescine. Rooted plants were...
Tipo: Journal article
Palavras-chave: Biological activities; Cucumis anguria; Multiple shoot induction; Plant growth regulators; Polyamines; Polyphenolic content.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400007

Effect of a commercial pectinmethylesterase on tomato paste consistency
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zúñiga-Hansen,María Elvira; Pérez-Torres,Eduardo; Caballero-Valdés,Eduardo; Fernández-Parodi,José.
Background: Consistency is one of the main traits that define commercial quality and price of tomato paste. Pectins are partially responsible for consistency in tomato paste, therefore enzymatic pectin modification could be used to increase paste consistency. Results: This work reports the effects of a commercial enzymatic preparation of pectin-methyl-esterase (PME) (NovoShape™) on tomato paste consistency taking into account variables as enzyme/substrate ratio (0,1% w/w - 1% w/w), reaction time (0 hr - 3 hrs) and reaction temperature (40ºC-60ºC). The results indicate that NovoShape™ increased consistency when reaction temperature ranged from 40 to 50ºC with an enzyme/substrate ratio of 0.5 to 1 (l PME solution/g tomato paste on dry base). On the other...
Tipo: Journal article
Palavras-chave: Pectin methyl esterase; Tomato paste; Viscosity.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000300009

Removal of malachite green from water by Firmiana simplex wood fiber
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pan,Xiangliang; Zhang,Daoyong.
This study shows that wood fiber of Phoenix tree (Firmiana simplex) is an effective adsorbent for malachite green (MG). MG sorption behavior onto the wood adsorbent was investigated in this study. Basic condition was favorable for MG adsorption to the adsorbent. The pseudo second order equation well described MG adsorption onto the wood adsorbent. The Freundlich Isotherm could describe the sorption data. The positive value of &amp;#916;H0 showed that adsorption of malachite green onto the wood adsorbent was endothermic. The negative values of &amp;#916;G at various temperatures indicate the spontaneous nature of the adsorption process.
Tipo: Journal article
Palavras-chave: Adsorption; Kinetics; Malachite green; Thermodynamics; Wood fiber.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400009

Optimization of beta-xylosidase recovery by reversed micelles using response surface methodology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hasmann,Francislene Andreia; Vieira Cortez,Daniela; Pessoa Júnior,Adalberto; Conceição Roberto,Inês.
beta-Xylosidase recovery by reversed micelles using CTAB cationic surfactant was performed under different experimental conditions. A 2²-full orthogonal design with center points was employed to optimize the recovery of this enzyme and to evaluate the influence of the factors CTAB (A) and butanol concentration (B) on the enzyme extraction. A mathematical model to represent the enzyme recovery as a function of A and B was proposed. According to the model, the CTAB and butanol concentrations necessary to attain the maximum beta-xylosidase recovery (43%) were 0.26 M and 29.4%, respectively. The results showed that the recovery value predicted by the model was similar to that obtained experimentally (44.3%).
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000200009

Strategic approaches to informing the public about biotechnology in Latin America
Provedor de dados: Electronic Journal of Biotechnology
Autores: Traynor,Patricia L; Adonis,Marta; Gil,Lionel.
Abstract &lt;a href="http://fbpe/img/ejb/v10n2/a01/reprint.html"&gt;Reprint (PDF)&lt;/a&gt; The benefits of today's biotechnology products are not evident to consumers. The public will accept biotechnology only when individuals decide for themselves that biotec products will contribute to their personal well-being. To make such a decision, people will need greater awareness and understanding of how biotechnology will affect the environment, human health, local and national economies, and the well-being of society. A low level of awareness and understanding about biotechnology is characteristic of Latin America and the Caribbean countries, as elsewhere, efforts to remedy poor public perception often seem inadequate and do not reflect a well-designed...
Tipo: Journal article
Palavras-chave: Biotechnology; GMOs; Public perception.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200001

Marker-assisted backcrossing using microsatellites and validation of SCAR Phs marker for resistance to white mold in common bean
Provedor de dados: Electronic Journal of Biotechnology
Autores: Carneiro,Flávia Fernandes; Santos,João Bosco dos; Leite,Monik Evelin.
Molecular markers may accelerate selection through the identification of plants with higher proportion of recurrent parent genome, as well as identifying those plants bearing target alleles like quantitative traits loci (QTLs) for white mold resistance. The objectives of this work were: 1) to employ microsatellite markers (SSR) in order to accelerate the recovery of recurrent parent genome 2) to validate sequence characterized amplified region (SCAR) Phs associated with a QTL that confers resistance to white mold, as previously identified in bean populations. Lines G122 and M20 were crossed, which generated 267 F1 plants from backcross (BC) BC1 and 113 plants from backcross BC2.SSR polymorphic markers were adopted. The relationship between BC plants and...
Tipo: Journal article
Palavras-chave: Backcross; Genetic similarity; Phaseolus vulgaris; SCAR; Sclerotinia sclerotiorum; SSR assisted selection.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600009

Bacteriophage prophylaxis against Salmonella enteritidis and Salmonella pullorum using Caenorhabditis elegans as an assay system
Provedor de dados: Electronic Journal of Biotechnology
Autores: Santander,Javier; Robeson,James.
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200012

Improved affinity selection using phage display technology and off-rate based selection
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yuan,Bin; Schulz,Philip; Liu,Ruitian; Sierks,Michael R.
Flow systems such as a BIAcore biosensor can be very efficient tools to isolate high affinity antibody fragments from affinity matured phage display libraries. Here we show that using flow based selection, we can readily isolate a variant with a 35-fold higher affinity, especially with a 7 fold better off-rate, compared to the parent clone after only a single round of selection from a second generation affinity matured phage display library. The flow system represents a fast method to isolate affinity improved antibody fragments and can be particularly useful for isolating antibodies to antigens that have poor solubility, are toxic to the host cell, or prone to aggregation.
Tipo: Journal article
Palavras-chave: Affinity maturation; Beta-amyloid (Abeta); Dissociation rate; Phage display.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200011

Biosafety education relevant to genetically engineered crops for academic and non-academic stakeholders in East Africa
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sengooba,Theresa; Grumet,Rebecca; Hancock,James; Zawedde,Barbara; Kitandu,Lazaro; Weebadde,Cholani; Karembu,Margaret; Kenya,Eucharia; Meredia,Karim; Nampala,Paul; Ochanda,James O; Quemada,Hector; Rubindamayugi,Mugassa.
Development and deployment of genetically engineered crops requires effective environmental and food safety assessment capacity. In-country expertise is needed to make locally appropriate decisions. In April 2007, biosafety and biotechnology scientists, regulators, educators, and communicators from Kenya, Tanzania, and Uganda, met to examine the status and needs of biosafety training and educational programs in East Africa. Workshop participants emphasized the importance of developing biosafety capacity within their countries and regionally. Key recommendations included identification of key biosafety curricular components for university students; collaboration among institutions and countries; development of informational materials for non-academic...
Tipo: Journal article
Palavras-chave: Biotechnology; Environmental safety; Kenya; Tanzania; Uganda.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000100001

Cloning and characterization of resistance gene analogs from under-exploited plant species
Provedor de dados: Electronic Journal of Biotechnology
Autores: Thirumalaiandi,Ramasubramanian; Selvaraj,Michael Gomez; Rajasekaran,Raghu; Subbarayalu,Mohankumar.
Genomic DNA sequences sharing homology with NBS region of resistance gene analogs were isolated and characterized from Pongamia glabra, Adenanthera pavonina, Clitoria ternatea and Solanum trilobatum using PCR based approach with primers designed from conserved regions of NBS domain. The presence of consensus motifs viz., kinase 1a, kinase 2, kinase 3a and hydrophobic domain provided evidence that the cloned sequences may belong to the NBS-LRR gene family. Conservation of tryptophan as the last residue of kinase-2 motif further confirms their position in non-TIR NBS-LRR family of resistance genes. The Resistance Gene Analogs (RGAs) cloned from P. glabra, A. pavonina, C. ternatea and S. trilobatum clustered together with well- characterized non-TIR-NBS-LRR...
Tipo: Journal article
Palavras-chave: Adenanthera pavonina; Clitoria ternatea; NBS-LRR; Pongamia glabra; Resistance gene analogs; Solanum trilobatum.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400004

Optimization in Agrobacterium-mediated transformation of Anthurium andraeanum using GFP as a reporter
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhao,Qing; Jing,Ji; Wang,Gang; Wang,Jie Hua; Feng,Yuan Yuan; Xing,Han Wen; Guan,Chun Feng.
Although Agrobacterium-mediated transformation protocols for many economically important plant species have been well established, protocol for a number of flowering plants including Anthurium andraeanum remains challenging. In this study, we report success in generating transgenic Anthurium andraeanum cv Arizona using Agrobacterium GV3101 strain harboring a binary vector carrying gfp as a reporter gene. The possibility of facilitating the screening process for transgenic plants expressing functional proteins using gfp marker was explored. In order to realize high transformation efficiency, different explant sources including undifferentiated callus pieces and petioles were compared for their regeneration efficiency and susceptibility to...
Tipo: Journal article
Palavras-chave: Cocultivation; Gene transfer; Green fluorescent protein; Regeneration.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500009

A new approach to chemical modification protocols of Aspergillus niger and sorption of lead ion by fungal species
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rafiu Awofolu,Omotayo; Okechukwu Okonkwo,Jonathan; Roux-Van Der Merwe,Renate; Badenhorst,Jackie; Jordaan,Erika.
Biomasses of five fungi species (Aspergillus niger, Penicillium austurianum, Saccharomyces cerevisiae, Mucor arcindloides and Trichoderma reesi were evaluated for their uptake of lead ion from aqueous solution using batch systems. Both dead and live fungal biomasses were comparatively studied for their adsorption efficiencies. The effect of pH as one of the primary factors that influences sorption efficiency of metal ions in solution was also studied. Modification of the fungal biomass with the least sorption capacity was carried out using a four-step procedure. Three different modifying agents under the optimised experimental conditions were used. The percentage uptake of lead ion by fungi species ranged from: Aspergillus niger: 6.71-64.95% and...
Tipo: Journal article
Palavras-chave: Aspergillus niger; Fungi species; Lead ion; Modification; Sorption.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400001

Genetic mapping of EST-SSR, SSR and InDel to improve saturation of genomic regions in a previously developed sunflower map
Provedor de dados: Electronic Journal of Biotechnology
Autores: Talia,Paola; Nishinakamasu,Verónica; Hopp,Horacio Esteban; Heinz,Ruth Amelia; Paniego,Norma.
In order to saturate a sunflower genetic map and facilitate marker-assisted selection (MAS) breeding for stress response, it is necessary to enhance map saturation with molecular markers localized in linkage groups associated to genomic regions involved in these traits. This work describes the identification and characterization of 1,134 simple sequence repeat (SSR) containing expressed sequence tags (EST) from unigenes available databases. Twelve of these functional markers as well as 41 public SSR markers were successfully localized in linkage groups, thus contributing to the saturation of specific regions on a reference genetic-linkage-map derived from recombinant inbred lines (RIL) mapping population from the cross between PAC2 x RHA266 lines. The...
Tipo: Journal article
Palavras-chave: EST-SSR; InDels; Linkage map; SSR; Sunflower.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600007

Preliminary results of using ESR to examine biofilms
Provedor de dados: Electronic Journal of Biotechnology
Autores: Whitehead,Neil Evan; Tani,Atushi; Kazue,Tazaki; Motoji,Ikeya.
This preliminary work shows ESR (Electron Spin Resonance) can be used to detect biofilms, particularly from Fe-metabolising bacteria. A film was detected by ESR as early as 1 day, hence possibly more sensitively than by fluorescent methods. Films can probably be detected as early as one hour. Spectra contain a very broad peak at g=2.13, probably due to ferrihydrite. Results of field experiments from streams and ponds in New Zealand and Japan, particularly the Minoh River, showed a general increase of ferrihydrite with time. Loss by exfoliation was later than 20 days. The rate of accumulation was faster in a nutrient-rich stagnant pond. Hematite (g=4.3) was often observed, magnetite (g=9) once, and usually small amounts of a common bacterial decay product....
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300011

Characterization of a multi-tolerant tannin acyl hydrolase II from Aspergillus carbonarius produced under solid-state fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Valera,Larissa Serrani; Jorge,João Atílio; Guimarães,Luis Henrique Souza.
Background Tannases are enzymes with biotechnological potential produced mainly by microorganisms as filamentous fungi. In this context, the production and characterization of a multi-tolerant tannase from Aspergillus carbonarius is described. Results The filamentous fungus A. carbonarius produced high levels of tannase when cultivated under solid-state fermentation using green tea leaves as substrate/carbon source and tap water at a 1:1 ratio as the moisture agent for 72 h at 30°C. Two tannase activity peaks were obtained during the purification step using DEAE-Cellulose. The second peak (peak II) was purified 11-fold with 14% recovery from a Sepharose CL-6B chromatographic column. The tannase from peak II (tannase II) was characterized as a heterodimeric...
Tipo: Journal article
Palavras-chave: Aspergillus; Microbial enzymes; Solid-state fermentation; Tannase; Tannic acid.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600013

Chilean IPNV isolates: Robustness analysis of PCR detection
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jorquera,Esteban; Morales,Paz; Tapia,David; Torres,Pamela; Eissler,Yoanna; Espinoza,Juan C; Conejeros,Pablo; Kuznar,Juan.
Background: The genomes of several infectious pancreatic necrosis viruses (IPNVs) isolated in Chile were sequenced with a single amplification approach for both segments A and B. The resulting sequences were then used to determine the conservation of the primer-binding regions used in polymerase chain reaction (PCR)-based diagnostic methods proposed in the literature. Thus, the robustness of each technique was studied, particularly the eventual effect of further mutations within the primer-binding sites. Results: On analysis, most methods currently used to detect Chilean IPNV varieties were deemed adequate. However, the primers were designed to be genogroup specific, implying that most detection methods pose some risk of detecting all strains prevalent in...
Tipo: Journal article
Palavras-chave: IPNV detection; Mismatch's Tm analysis; QPCR.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000200005

Allelic variation at the Vrn-A1, Vrn-B1, Vrn-D1, Vrn-B3 and Ppd-D1a loci of Pakistani spring wheat cultivars
Provedor de dados: Electronic Journal of Biotechnology
Autores: Iqbal,Muhammad; Shahzad,Armghan; Ahmed,Iftikhar.
Flowering time in bread wheat (Triticum aestivum L.) is controlled by vernalization and photoperiod response, and earliness per se genes. The genetic basis of flowering time has not been investigated in Pakistani bread wheat. This study was, therefore, conducted to determine the allelic composition at Vrn-A1, Vrn-B1, Vrn-D1, Vrn-B3 and Ppd-D1a loci of 59 Pakistani spring bread wheat cultivars. These cultivars, along with 4 isogenic lines for vernalization genes were characterized with previously reported DNA markers designed for detecting allelic variation at 4 Vrn (Vernalization) and 1 Ppd (Photoperiod) loci. Spring habit Vrn-A1a allele was found in 36% cultivars either alone or with spring habit Vrn-B1 and Vrn-D1 alleles. Two wheat cultivars had the...
Tipo: Journal article
Palavras-chave: Photoperiod; Spring growth habit; Triticum aestivum; Vernalization.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100001

The multinational biosafety project of the Organization of American States
Provedor de dados: Electronic Journal of Biotechnology
Autores: Verastegui,Javier; Martínez,Víctor; Roca,Willy; de Peña,Myriam; Gil,Lionel.
The Organization of American States is supporting the project "Biosafety Regulations in Latin America and The Caribbean within the framework of the International Biosafety Protocol". The general objective is to strengthen national skills for the assessment and management of risks of biotechnology food products, and to build up public awareness about their benefits and risks in the participant countries, with the ultimate goal to promote their safe and sustainable use within a protective and trusting environment for the public. The first phase has been focused on the evaluation of the political and regulatory systems in Chile, Peru and Colombia, identification of needs, and development of a series of biosafety seminar-workshops in the three countries, with...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000100007

Deletion of DNA sequences of using a polymerase chain reaction based approach
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pérez-Pinera,Pablo; Menéndez-González,Manuel; Vega,José Antonio.
We developed a simple, rapid and reliable method to delete DNA fragments in plasmids using a polymerase chain reaction based amplification of the circular DNA sequence that excludes the fragment to be deleted. The primers are designed to contain a non-complementary 5' sequence consisting of a restriction enzyme target sequence. Following PCR amplification, the plasmid is digested with Dpn I to eliminate the template DNA, with the chosen restriction enzyme, and ligated. The only limitation is the selection of the restriction enzyme target sequence that must not be present in the original plasmid. The method is straightforward in its execution and success relies on a meticulous primer design that permits us obtain 100% of transformants containing the desired...
Tipo: Journal article
Palavras-chave: Deletion; Mutagenesis; Polymerase chain reaction; Plasmid.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500018

Effect of extrinsic and intrinsic parameters on inulinase production by Aspergillus niger ATCC 20611
Provedor de dados: Electronic Journal of Biotechnology
Autores: Dinarvand,Mojdeh; B. Ariff,Arbakariya; Moeini,Hassan; Masomian,Malihe; Mousavi,Seyed Sadegh; Nahavandi,Reza; Mustafa,Shuhaimi.
Background: Inulinase is a versatile enzyme from glycoside hydrolase family which targets the &amp;#946;-2, 1 linkage of fructopolymers. In the present study, the effect of medium composition and culture conditions on inulinase production by Aspergillus niger ATCC 20611 was investigated in shake-&amp;#64258;asks. Results: The highest extracellular inulinase (3199 U/ ml) was obtained in the presence of 25% (w/v) sucrose, 0.5% (w/v) meat extract, 1.5% (w/v) NaNO3 and 2.5 mM (v/v) Zn2+, at initial pH of 6.5, temperature 35ºC and 6% (v/v) of spores suspension in the agitation speed of 100 rpm. Surfactants showed an inhibitory effect on enzyme production. The optimum temperature for inulinase activity was found to be 50ºC. TLC analysis showed the presence of...
Tipo: Journal article
Palavras-chave: Aspergillus niger ATCC 20611; Culture optimization; Inulinase.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000400005

Prospects for using transgenic resistance to insects in crop improvement
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sharma,Hari C.; Sharma,Kiran K.; Seetharama,Nadoor; Ortiz,Rodomiro.
Integrated pest management has historically placed great hopes on host plant resistance. However, conventional host-plant resistance to insects involves quantitative traits at several loci. As a result, the progress has been slow and difficult to achieve. With the advent of genetic transformation techniques, it has become possible to clone and insert genes into the crop plants to confer resistance to insect pests. Resistance to insects has been demonstrated in transgenic plants expressing genes for delta-endotoxins from Bacillus thuringiensis (Bt), protease inhibitors, enzymes and plant lectins. Most of the plant derived genes produce chronic rather than toxic effects and some insect pests are not sensitive to some of these factors. The potential of plant...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000200001

Phage-resistance of Salmonella enterica serovar Enteritidis and pathogenesis in Caenorhabditis elegans is mediated by the lipopolysaccharide
Provedor de dados: Electronic Journal of Biotechnology
Autores: Santander,Javier; Robeson,James.
Phage therapy has been used in the past as an alternative therapy against bacterial pathogens. However, phage-resistant bacterial strains can emerge. Some studies show that these phage-resistant strains are avirulent. In this study, we report that phage-resistant strains of Salmonella enterica serovar Enteritidis (hereafter S. Enteritidis) were avirulent in the Caenorhabditis elegans animal model. We isolated phage-resistant strains of S. Enteritidis ATCC 13076 by using three lytic phages (f2&amp;#945;SE, f3&amp;#945;SE and f18&amp;#945;SE). In these mutants, we explored different virulence factors like lipopolysaccharide (LPS), virulence plasmid (Pla), motility and type I fimbriae, all of which may have effects on virulence and could furthermore be...
Tipo: Journal article
Palavras-chave: Animal model; Bacteriophage prophylaxis; Caenorhabditis elegans; Phage resistance; Salmonella.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400015

Removal of heavy metals by exopolymeric substances produced by resistant purple nonsulfur bacteria isolated from contaminated shrimp ponds
Provedor de dados: Electronic Journal of Biotechnology
Autores: Panwichian,Saijai; Kantachote,Duangporn; Wittayaweerasak,Banjong; Mallavarapu,Megharaj.
Two purple nonsulfur bacteria (PNSB) strains, Rhodobium marinum NW16 and Rhodobacter sphaeroides KMS24 were investigated for their potential to remove heavy metals (HMs) from contaminated shrimp pond water. Tolerance of both PNSB strains growing with both microaerobic-light and aerobic-dark conditions, based on their minimum inhibitory concentrations, was in the order of Cu2+ &gt; Zn2+ &gt; Cd2+ (Pb precipitation occurred at 0.34 mM). Results from a scanning electron microscope equipped with an energy dispersive X-ray spectrometer (SEM-EDX) indicated that Cu2+ and Zn2+ altered the cellular morphology of both strains and accumulated HMs were found in their cells. The highest amounts of both cations were found in their cell walls followed by the cytoplasm...
Tipo: Journal article
Palavras-chave: Contamination; Exopolymeric substances; Heavy metals; Photosynthetic bacteria; Shrimp farming.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400002

DNA demethylation during Chrysanthemum floral transition following short-day treatment
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Zhongai; Li,Jie; Yanhua,Liu; Wang,Zicheng.
Background: Analytical techniques such as methylation-sensitive amplification polymorphism and high-performance liquid chromatography were used to detect variation in DNA methylation of mature Chrysanthemum leaves during the floral transition induced by short-day (SD) treatment. Results: For both early- and late-flowering cultivars, the time from the date of planting to the appearance of the capitulum bud and early blooming were significantly shorter than those of the control. The capitulum development of the early-flowering cultivar was significantly accelerated compared to the control, unlike the late-flowering cultivar. The DNA methylation percentage of leaves was significantly altered during flower development. For the early-flowering cultivar, DNA...
Tipo: Journal article
Palavras-chave: Chrysanthemum; DNA; Methylation; Floral transition; Short day.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300009

General and microbiological aspects of solid substrate fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Raimbault,Maurice.
At first some general considerations about specificity and characteristics of SSF, their advantages and disadvantages as compared to LSF, are presented. Microorganisms involved in solid substrate fermentations are identified, considering the better performances of filamentous fungi. The solid substrates and their basic macromolecular compounds are detailed in relation to this complex and heterogeneous system. Biomass measurement is examined in detail, as well as environmental factors, both essential for studying and optimising solid substrate fermentations.
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000300007

Evaluation of concentrated milk whey as a supplement for SF9 Spodoptera frugiperda cells in culture
Provedor de dados: Electronic Journal of Biotechnology
Autores: Batista,Fabiana R. X.; Pereira,Carlos A.; Mendonça,Ronaldo Z.; Moraes,Angela M.
Insect cell culture has become increasingly useful for the production of heterologous proteins as well as of baculovirus polyhedra, and several different culture media formulations can be employed for this purpose. The goal of this work was to assess the potential of lyophylized milk whey ultra filtration retentate (MWR) when associated to yeast extract (YE), glucose and Pluronic F68 (PF68) to partially replace fetal calf serum (FBS) in Spodoptera frugiperda Sf9 cells culture in Grace's medium, aiming AgMNPV baculovirus production. Batch cultivation results showed that the yeast extract and the milk whey concentrate effectively increased cell concentration to about half the level commonly verified for the Sf900II serum-free medium. A 4-fold increase in...
Tipo: Journal article
Palavras-chave: Baculovirus; Concentrated milk whey; Grace's medium; Insect cells; Media formulation; Spodoptera frugiperda Sf9.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500007

Engineering Escherichia coli for autoinducible production of n-butanol
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Qinglong; ding,Yi; Liu,Li; Shi,Jiping; Sun,Junsong; Xue,Yongchang.
Background Escherichia coli does not produce n-butanol naturally, but can be butanologenic when related enzymes were expressed using inducible elements on plasmids. In this study we attempted to confer E. coli strain capability of automatic excretion of the chemical by employing a native anaerobic promoter. Also, a novel DNA kit was designed for PCR preparation of linear DNA fragments to perform strain modification. The kit is primarily composed of two mother vectors, co-transformation of linear DNAs into E. coli can simultaneously introduce two butanol synthetic operons into the chromosome and create two in-frame gene deletions at targeted native loci. Results E. coli strain Bw2V carries plasmid pCNA-PHC and pENA-TA, both utilizes native anaerobic...
Tipo: Journal article
Palavras-chave: Anaerobic promoter; Escherichia coli; Metabolic engineering; N-Butanol; Recombination.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200013

Introgression of LTP2 gene through marker assisted backcross in barley (Hordeum vulgare L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mikolajczak,Krzysztof; Ogrodowicz,Piotr; Surma,Maria; Adamski,Tadeusz; Kuczyñska,Anetta.
Background: Marker-assisted introgression currently represents the most widely spread application of DNA markers as an aid to selection in plant breeding. New barley germplasm should be supplemented by genes that facilitate growth and development under stressful conditions. The homology search against known genes is a fundamental approach to identify genes among the generated sequences. This procedure can be utilized for SNP search in genes of predicted function of interest and associated gene ontology (GO). Results: Backcross breeding enhanced by marker selection may become a powerful method to transfer one or a few genes controlling a specific trait. In the study, the integrated approach of combining phenotypic selection with marker assisted backcross...
Tipo: Journal article
Palavras-chave: BC lines; Gene annotation; Semi-dwarf gene; Single nucleotide polymorphism spring barley; Marker selection; Marker-assisted backcrossing; Marker-assisted introgression; DNA markers; Selection in plant breeding.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600014

1,3-Propanediol production from crude glycerol by Clostridium butyricum DSP1 in repeated batch
Provedor de dados: Electronic Journal of Biotechnology
Autores: Szymanowska-Powalowska,Daria.
Background The production of biofuels from renewable energy sources is one of the most important issues in industrial biotechnology today. The process is known to generate various by-products, for example crude glycerol, which is obtained in the making of biodiesel from rapeseed oil. Crude glycerol may be utilized in many ways, including microbial conversion to 1,3-propanediol (1,3-PD), a raw material for the synthesis of polyesters and polyurethanes. Results The paper presents results of a study on the synthesis of 1,3-propanediol from crude glycerol by a repeated batch method with the use of Clostridium butyricum DSP1. Three cycles of fermentation medium replacement were carried out. The final concentration of 1,3-PD was 62 g/L and the maximum...
Tipo: Journal article
Palavras-chave: Environmental stress; Fermentation; High-performance liquid chromatography.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600011

T-DNA insertional mutagenesis in Arabidopsis: a tool for functional genomics
Provedor de dados: Electronic Journal of Biotechnology
Autores: Radhamony,Resmi Nath; Mohan Prasad,Anand; Srinivasan,Ramamurthy.
With the availability of complete genome sequences of several organisms, the focus has shifted from structural genomics to functional genomics, specifically in plants where the complete genomic sequences are becoming available i.e., Arabidopsis and rice. Agrobacterium mediated transformation which is exploited for transgenic technology is also being used as an effective mutagen and as a tool for functional genomics in higher plants. Besides the fact that the insertion of T-DNA element into a gene can lead to loss or gain of function, ingenious use of a variety of vectors have led to the identification of genes and regulatory elements in Arabidopsis. In this review, we highlight the progress made in the field of functional genomics of Arabidopsis using...
Tipo: Journal article
Palavras-chave: Arabidopsis; Functional genomics; Insertional mutagenesis; Promoter trapping; T-DNA tagging.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100012

Isolation of high quality RNA from Polyporus umbellatus (Pers.) Fries
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Yuejin; Qin,Yali; Guo,Lijun; Zhou,Zili; Liang,Zongsuo; Zhang,Chenlu; Guo,Hongbo.
Background: The dried sclerotium of medicinal fungus Polyporus umbellatus (Pers.) Fries has many pharmacological functions such as diuretic and anticancer activity, in which high-content polysaccharides may play an important role. However, RNA isolation is difficult in filamentous fungi and lacking in P. umbellatus. Results: Five methods for RNA extraction from five strains collected from four provinces were assessed for their ability to recover a high-quality RNA applicable for sequence-related amplification polymorphism (SRAP) PCR and GDP-D-mannose pyrophosphorylase (GMP) gene expression profiles. Both A260/A280 and A260/A230 ratios of the best Trizol Plus + RNAiso-mate for Plant Tissue method are around 2 with a yield of 1122.00 ± 0.21 ng &amp;#956;l-1....
Tipo: Journal article
Palavras-chave: Chuling; Medicinal fungus; Polyporus umbellatus; RNA isolation.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500010

Potential application of protease isolated from Pseudomonas aeruginosa PD100
Provedor de dados: Electronic Journal of Biotechnology
Autores: Najafi,Mohsen Fathi; Deobagkar,Dileep; Deobagkar,Deepti.
A protease isolated from Pseudomonas aeruginosa PD100 could act in the presence of SDS and Tween 80. This protease could be useful for degradation of protein in the presence of solvent, dehairing of cow skin and degradation of natural proteins. The immobilized protease showed 15-20% increases in temperature stability and the entrapped enzyme retained 83% of its initial activity after six cycles. With respect to properties of the enzyme and its capability for degradation of different protein sources, this protease finds potential application for waste treatment, used in detergents and leather industry
Tipo: Journal article
Palavras-chave: Blood clot; Protease; Pseudomonas aeruginosa PD100; SDS; Solvent.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200009

Identification of differentially expressed genes in developing cotton fibers (Gossypium hirsutum L) through differential display
Provedor de dados: Electronic Journal of Biotechnology
Autores: Iqbal,Saima; Bashir,Aftab; Naseer,Hafiza Masooma; Ahmed,Moddassir; Malik,Kauser A.
Cotton fibers are differentiated, non-dividing cells that originate from the epidermal layer of developing ovules. To identify genes involved in cotton fiber development, we performed non-radioactive differential display reverse transcriptase PCR (DDRT-PCR) on the purified mRNA. This technique was tested on mRNA isolated from five different developmental stages of cotton fiber including 0, 5, 10, 15 and 20 DPA (days after pollination). The mRNA purified from total RNA was reversibly transcribed using three anchored oligo-dT primers. Polymerase chain reaction (PCR) amplification of each cDNA preparation was carried out in combination with seven arbitrary primers. The amplified products were resolved on 1% agarose gel containing ethidium bromide. DNA was...
Tipo: Journal article
Palavras-chave: Cotton fiber; Differentially expressed transcripts; Gossypium hirsutum; Non-radioactive.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100005

Influence of the pH of glutaraldehyde and the use of dextran aldehyde on the preparation of cross-linked enzyme aggregates (CLEAs) of lipase from Burkholderia cepacia
Provedor de dados: Electronic Journal of Biotechnology
Autores: Caballero Valdés,Eduardo; Wilson Soto,Lorena; Aroca Arcaya,Germán.
The preparation of cross-linked enzyme aggregates (CLEAs) of lipase has been a challenge due the low amount of lysine residues that lipases have on their surface. The results show that CLEAs prepared using dextran aldehyde (100-200KDa) have a higher hydrolysis activity and particle size (activities between 3186 Â± 21 U/g of CLEA and 4800 Â± 30 U/g of CLEA and particle sizes between 52.6 Â± 18.7 Âµm and 126.2 Â± 53.5 Âµm) than CLEAs prepared with glutaraldehyde (0.1 KDa) (activities between 894 Â± 16 U/g of CLEA and 2874 Â± 20 U/g of CLEA and particle sizes between 21.2 Â± 5.1 Âµm and 83.4 Â± 24.9 Âµm); Thermal stability assays of bioctalysts at 60ÂºC at pH 7.0 using phosphate buffer 25 mM showed that CLEAs prepared with dextran aldehyde have lower residual...
Tipo: Journal article
Palavras-chave: Albumin; Dextran aldehyde; Glutaraldehyde; Immobilisation; Lipase.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300010

Fibrinolytic protease production by new Streptomyces sp: DPUA 1576 from Amazon lichens
Provedor de dados: Electronic Journal of Biotechnology
Autores: M.M. Silva,Germana; Bezerra,Raquel P; Teixeira,José A; Porto,Tatiana S; Lima-Filho,José L; Porto,Ana Lúcia F.
Background Streptomyces sp. DPUA 1576 from Amazon lichens was studied to protease and fibrinolytic production. A 2² factorial experimental design was applied to optimize its protease enzyme production using two independent variables, namely soybean flour and glucose concentrations. Results The optimal conditions to obtain high protease production (83.42 U/mL) were 1.26% soybean flour and 1.23% glucose concentration. A polynomial model was fitted to correlate the relationship between the two variables and protease activity. In relation to fibrinolytic activity, the highest activity of 706.5 mm² was obtained at 1.7% soybean flour and 1.0% glucose concentration, which was 33% higher than plasmin. Fibrinolytic production was not optimized in the studied...
Tipo: Journal article
Palavras-chave: Actinomycetes; Factorial design; Glucose; Microbial enzymes; Soybean flour.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100004

Citric acid fermentation by mutant strain of Aspergillus niger GCMC-7using molasses based medium
Provedor de dados: Electronic Journal of Biotechnology
Autores: ul-Haq,Ikram; Ali,Sikander; Qadeer,M.A.; Iqbal,Javed.
Citric acid fermentation of cane-molasses by submerged fermentation in 15 L stirred fermentor (working volume 9 L) was carried out. A hyper mutant strain of Aspergillus niger GCMC-7 was used in the present study which was obtained from the culture collection of our own labs. Ferrocyanide treated molasses [K4Fe(CN)6 200 ppm] medium containing sugar 150 g/l was employed as the basal fermentation medium. Different cultural conditions such as incubation temperature (30ºC), initial pH (6.0), air supply (1.0 l-1l-1min), agitation intensity (200 rpm) and time profile (144 h after inoculation) were optimised for enhanced citric acid production. Maximum amount of anhydrous citric acid obtained during the course of study was 106.65 g/l, with a sugar consumption of...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200007

Purification and characterization of ß-glucosidase from Melanocarpus sp. MTCC 3922
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kaur,Jatinder; Chadha,Bhupinder S; Kumar,Badhan A; Kaur,Ghatora, S; Saini,Harvinder S.
This study reports the purification and characterization of ß-glucosidase from a newly isolated thermophilic fungus, Melanocarpus sp. Microbial Type Culture Collection (MTCC) 3922. The molecular weight of ß-glucosidase was determined to be ~ 92 and 102 kDa with SDS PAGE and gel filtration, respectively, and pI of ~ 4.1. It was optimally active at 60ºC and pH 6.0, though was stable at 50ºC and pH 5.0 - 6.0. The presence of DTT, mercaptoethanol and metal ions such as Na+, K+, Ca2+, Mg2+and Zn2+ positively influenced the activity of ß-glucosidase but the activity was inhibited in the presence of CuSO4. ß-Glucosidase recognized pNP- ß-glucopyranoside (pNPG) as the preferred substrate, and showed very low affinity for pNP- ß-D-cellobioside. Km and Vmax for the...
Tipo: Journal article
Palavras-chave: SS-glucosidase; Melanocarpus sp; Purification; Substrate specificity; Transglycosylation.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200010

Sugar cane bagasse as feedstock for second generation ethanol production: Part I: Diluted acid pretreatment optimization
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vargas Betancur,Gabriel J; Pereira Jr,Nei.
Tons of sugar cane bagasse are produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a potential source for second-generation ethanol production. Diluted acid hydrolysis is one of the most efficient pretreatments for hemicellulosic solubilization. The hydrolysate obtained is rich in xylose, which can be converted to ethanol by Pichia stipitis. This work used a statistical approach and the severity factor to investigate the effects of factors associated with the diluted acid hydrolysis process (acid concentration, solid:liquid ratio and time of exposure) on various response variables (xylose concentration, hydrolysis yield, inhibitor concentration and hydrolysate fermentability). The severity factor had a strong...
Tipo: Journal article
Palavras-chave: Hemicellulose hydrolysis; Severity factor; Xylose.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300010

Enzymological characterization of pineapple extract for potential application in oak tasar (Antheraea proylei J.) silk cocoon cooking and reeling
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rupachandra Singh,Laishram; Ranjana Devi,Yengkokpam; Kunjeshwori Devi,Sanjenbam.
Proteinases have the potential to effect partial solubilization of the proteinaceous gum sericin involved in binding the silk strands together in cocoon, an essential step in the silk cocoon cooking and reeling. Therefore, pineapple extract rich in cysteine proteinases was enzymologically characterized for its potential application in oak tasar (Antheraea proylei J.) silk cocoon cooking and reeling. Optimum sodium carbonate concentration (9.8 mM) and optimum temperature (60ºC) for the proteinase activity were determined. Though relatively thermostable, an enhanced activity loss was observed when the extract was incubated in the temperature range 70-90ºC with sodium carbonate. Bulk of the activity (80-83%) remained after 1 hr of time-dependent inactivation...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300005

Production of citric acid by Aspergillus niger using cane molasses in a stirred fermentor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ali,Sikander; Haq,Ikram-ul-; Qadeer,M.A.; Iqbal,Javed.
The present investigation deals with the kinetics of submerged citric acid fermentation by Aspergillus niger using blackstrap molasses as the basal fermentation media. A laboratory scale stirred fermentor of 15-L capacity having working volume of 9-L was used for cultivation process and nutritional analysis. Among the 10 stock cultures of Aspergillus niger, the strain GCBT7 was found to enhance citric acid production. This strain was subjected to parametric studies. Major effects were caused due to oxygen tension (1.0 l/l/min), pH value (6.0) and incubation temperature (30ºC). All fermentations were carried out following the growth on 150 g/l raw molasses sugars for 144 hours. Ferrocyanide (200 ppm) was used to control the trace metals present in the...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300010

Rapid multiplication and in vitro production of leaf biomass in Kaempferia galanga through tissue culture
Provedor de dados: Electronic Journal of Biotechnology
Autores: Parida,Reena; Mohanty,Sujata; Kuanar,Ananya; Nayak,Sanghamitra.
An efficient protocol has been established for rapid multiplication and in vitro production of leaf biomass in Kaempferia galanga L, a rare medicinal plant. Different plant growth regulators like Benzyladenine (BA), Indoleacetic acid (IAA), Indolebutyric acid (IBA), Napthaleneacetic acid (NAA) and adenine sulphates (Ads) have been tried for induction of multiple shoots using lateral bud of rhizome as explants. The highest rate of shoot multiplication (11.5 ± 0.6) shoot/explant as well as leaf biomass production (7.4 ± 0.3) gram/explant was observed on Murashige and Skoog medium supplemented with Benzyladenine (1 mg/l) and Indoleacetic acid (0.5 mg/l). Data of shoot multiplication and leaf biomass production were statistically analysed. Upon excission of...
Tipo: Journal article
Palavras-chave: Growth regulators; Kaempferia; In vitro propagation; Leaf biomass.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400005

Polymorphism of four microsatellites and their polymerisation effect on litter size in Boer goats
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Jian gang; Hou,Jin-Xing; Li,Guang; Zhu,Guang Qin; Cao,BinYun.
Background: Finding molecular markers linked to quantitative trait loci is the first step in marker-assisted selection (MAS). Microsatellites are excellent molecular markers because of their large numbers, even distribution in the genome, and high polymorphism. In this study, the polymerisation effect of four microsatellites (OarAE101, BM1329, BM143, and LSCV043) on litter size was analysed using microsatellite markers and pedigrees. Results: The results indicate that the polymerisation effect of four microsatellite loci significantly affected the litter size. E5E10F2F6G1G5H6H11 and E3E8F5F7G1G5H3H9 had the highest and lowest litter sizes in the F2 generation, respectively. The polymerisation effect value (v) of the E5E10 genotype was 3.18% higher than...
Tipo: Journal article
Palavras-chave: Microsatellite marker; Pedigrees; Polymerisation effect; Polymorphism.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400011

Molecular cloning and expression of a putative crustacean hyperglycemic hormone of Litopenaeus vannamei in Pichia pastoris
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sánchez-Castrejón,Edna; Ponce-Rivas,Elizabeth; Aguilar,Manuel B; Díaz,Fernando.
Crustacean hyperglycemic hormone (CHH) is the most abundant and best studied member of the CHH/MIH/GIH neuropeptide hormone family. CHH plays a major role in controlling glucose levels in the hemolymph, and it also has significance in regulating molting, reproduction, and osmoregulation. In contrast, molt-inhibiting hormone (MIH) is responsible for maintaining animals in an intermolt stage. In this study, Liv-MIH-1 cDNA, which encodes a mature neuropeptide from the eyestalk of white shrimp, Litopenaeus vannamei, was expressed in methylotrophic yeast (Pichia pastoris KM71) under the control of an alcohol oxidase promoter. Recombinant Liv-MIH-1 was secreted into the culture medium using the &amp;#945;-factor prepro-sequence without Glu-Ala repeats. The...
Tipo: Journal article
Palavras-chave: CHH; Litopenaeus vannamei; Pichia pastoris; Recombinant protein.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400009

Endophytic microorganisms: a review on insect control and recent advances on tropical plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Azevedo,João Lúcio; Maccheroni Jr.,Walter; Pereira,José Odair; de Araújo,Welington Luiz.
In the past two decades, a great deal of information on the role of endophytic microorganisms in nature has been collected. The capability of colonizing internal host tissues has made endophytes valuable for agriculture as a tool to improve crop performance. In this review, we addressed the major topics concerning the control of insects-pests by endophytic microorganisms. Several examples of insect control are described, notably those involving the interactions between fungi and grazing grasses from temperate countries. The mechanisms by which endophytic fungi control insect attacks are listed and include toxin production as well as the influence of these compounds on plant and livestock and how their production may be affected by genetic and environmental...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000100004

Expression of a Haemonchus contortus cysteine protease in the baculovirus system
Provedor de dados: Electronic Journal of Biotechnology
Autores: Miranda-Miranda,Estefan; Murillo-Sánchez,María Hortensia; Cossío-Bayúgar,Raquel.
A Haemonchus contortus recombinant Cysteine Protease (CP) was expressed in the baculovirus system. The CP gene was isolated by PCR from H. contortus cDNA, the PCR amplicon was cloned downstream to the polihedrin promoter within a bacterial expression vector, Sf9 insect cells were used for simultaneous co-transfection with the CP-vector and baculovirus naked DNA, which originated recombinant viruses by homologous recombination capable to express recombinant CP in an insect cell culture. A recombinant protease was identified as a fusion protein with a Ni lithium affinity 6XHis group. Recombinant CP was purified by affinity chromatography to obtain active recombinant protease identified by H. contortus experimentally infested ovine sera on a western blot as a...
Tipo: Journal article
Palavras-chave: Haemonchosis; Molecular cloning; Recombinant protease; Synthetic substrates; Western blot.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200007

Cold resistance in plants: A mystery unresolved
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jan,Nishawar; ul-Hussain,Mahboob; Andrabi,Khurshid I.
Herbaceous temperate plants are capable of developing freezing tolerance when they are exposed to low nonfreezing temperatures. Acquired freezing tolerance involves extensive reprogramming of gene expression and metabolism. Recent full-genome transcript profiling studies, in combination with mutational and transgenic plant analyses, have provided a snapshot of the complex transcriptional network that operates under cold stress. The changes in expression of hundreds of genes in response to cold temperatures are followed by increases in the levels of hundreds of metabolites, some of which are known to have protective effects against the damaging effects of cold stress. Genetic analysis has revealed important roles for cellular metabolic signals, and for RNA...
Tipo: Journal article
Palavras-chave: Cold acclimation; Cold resistance; CORs (cold regulated).
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300014

Frequency of transferable multiple antibiotic resistance amongst coliform bacteria isolated from a treated sewage effluent in Antofagasta, Chile
Provedor de dados: Electronic Journal of Biotechnology
Autores: Silva,Juan; Castillo,Gabriela; Callejas,Lorena; López,Héctor; Olmos,Janet.
Antibiotic-resistant coliform bacteria from raw and treated water from activated sludge of a sewage treatment plant were isolated on eosin methylene blue agar (EMB) plates in the separate presence of ampicillin, tetracycline, chloramphenicol and streptomycin. Antibiotic resistant coliforms obtained from inflow and effluent waters were studied to determine influences of treatment on the species composition, resistance patterns and transferable resistance in these bacteria. The bacterial counts obtained showed a high proportion of antibiotic resistant coliforms in the treated effluent. The resistant coliform species were eliminated at different rates by the treatment. Escherichia coli decreased, whereas the proportion of Klebsiella sp increased. The...
Tipo: Journal article
Palavras-chave: Antibiotic resistance; Coliforms; Plasmid; Sewage treatment; Water pollution.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500008

The use of rice straw broth as an appropriate medium to isolate purple nonsulfur bacteria from paddy fields
Provedor de dados: Electronic Journal of Biotechnology
Autores: Nunkaew,Tomorn; Kantachote,Duangporn; Nitoda,Teruhiko; Kanzaki,Hiroshi.
The aims were to explore an appropriate isolating medium for obtaining purple nonsulfur bacteria (PNSB) for use as biofertilizers in saline paddy fields and to obtain pure cultures. We therefore chose a defined isolating medium containing 0.25% NaCl, (Glutamate-Acetate broth, GA) and a rice straw broth to compare them for numbers of PNSB obtained, time to obtain pure cultures, diversity and costs. A total of 30 water and 30 sediment samples were collected from saline paddy fields in southern Thailand and used to isolate PNSB in both the isolating media. Based on 60 samples and a period of 13 days incubation under anaerobic light conditions, a greater number of samples produced PNSB growth in GA broth after only day 3; however, after that the rice straw...
Tipo: Journal article
Palavras-chave: Biofertilizer; Isolation; Paddy field; Purple nonsulfur bacteria; Rice straw broth.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600007

Expression and purification of soluble single-chain Fv against human fibroblast growth factor receptor 3 fused with Sumo tag in Escherichia coli
Provedor de dados: Electronic Journal of Biotechnology
Autores: Liu,Zixuan; Zhang,Jizhou; Fan,Hongqiong; Yin,Ruofeng; Zheng,Zhong; Xu,Qian; Liu,Qing; He,Haiting; Peng,Xiaofan; Wang,XinXin; Li,Xiaokun; Xiao,Yechen.
Background Overexpression or mutated activation of Fibroblast growth factor receptor 3 (FGFR3) is involved in the pathogenesis of many tumors. More and more studies focus on the potential usage of therapeutic antibodies against FGFR3. Results In this study, a novel single-chain Fv (ScFv) against FGFR3 was prepared and characterized. To achieve the soluble expression, ScFv was fused with Sumo (Small ubiquitin-related modifier) by polymerase chain reaction (PCR), and cloned into pET-20b. The recombinant bacteria were induced by 0.5 mM Isopropyl-ß-d-thiogalactopyranoside (IPTG) for 16 h at 20°C, and the supernatant liquid of Sumo-ScFv was harvested and purified by Ni-NTA chromatography. After being cleaved by the Sumo protease, the recombinant ScFv was...
Tipo: Journal article
Palavras-chave: Escherichia coli; Fibroblast growth factor receptor 3; Single-chain Fv antibody; Soluble expression; Sumo tag.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400008

Kinetic analysis and effect of culture medium and coating materials during free and immobilized cell cultures of Bifidobacterium animalis subsp. lactis Bb 12
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jalili,Hasan; Razavi,Hadi; Safari,Mohammad; Amrane,Abdeltif.
Microencapsulation technique appears helpful for more protection of Bifidobacteria against acid inhibitory effect. The effect of medium composition and product inhibitory in free cell culture, as well as the effect of the coating materials in immobilized cells, on biomass growth, acid production and substrate utilization kinetics of Bifidobacterium animalis subsp. lactis Bb 12 in uncontrolled batch fermentation was examined. The Monod and the Luedeking and Piret equations with a product inhibition term involving toxic power terms improved model efficiency for both growth and production. The model showed that media and coating materials had an effect on toxic power terms. Cell immobilization had a positive impact on B. animalis culture. Kinetic analysis...
Tipo: Journal article
Palavras-chave: Bifidobacterium; Immobilization; Kinetic models; Medium composition.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300002

Microsatellites within genes and ESTs of the Pacific oyster Crassostrea gigas and their transferability in five other Crassostrea species
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Qi; Liu,Shikai; Kong,Lingfeng.
We developed 15 novel polymorphic microsatellites for the Pacific oyster Crassostrea gigas by screening genes and expressed sequence tags (ESTs) found in GenBank. The number of alleles per locus ranged from two to 24 with an average of 8.7, and the values of observed heterozygosity (Ho) and expected heterozygosity (He) ranged from 0.026 to 0.750 and from 0.120 to 0.947, respectively. No significant pairwise linkage disequilibrium was detected among loci and eight loci conformed to Hardy-Weinberg equilibrium. Transferability of the markers was examined on five other Crassostrea species and all the markers were amplified successfully in at least one species. These new microsatellites should be useful for population genetics, parentage analysis and genome...
Tipo: Journal article
Palavras-chave: Indwelling medical devices; Infections; Surface attachment.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300015

Effect of nickel chloride on Arabidopsis genomic DNA and methylation of 18S rDNA
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Zhongai; Chen,Xin; Li,Suoping; Wang,Zicheng.
Background In recent years, nickel (Ni) has been widely applied in industrial and agricultural production and has become a kind of environmental pollution. In this study, the effect of nickel chloride (NiCl2) with different concentrations on Arabidopsis genomic stability and DNA methylation has been demonstrated. The nucleolus variation and 18S rDNA methylation after NiCl2 treatment have been analyzed. Results The results are as follows: (1) The NiCl2 could result in heritable genomic methylation variations. The genomic DNA methylation variations have been detected by methylation-sensitive amplified polymorphism (MSAP) molecular markers, and the result showed that after NiCl2 treatment, there was methylation variation in T0 generation seedlings, and...
Tipo: Journal article
Palavras-chave: DNA methylation; Heavy metal; Methylation sensitive amplified polymorphism (MSAP); Nickel.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100010

Molecular characterization of 'Candidatus Liberibacter' species/strains causing huanglongbing disease of citrus in Kenya
Provedor de dados: Electronic Journal of Biotechnology
Autores: Magomere,Titus O; Obukosia,Silas D; Mutitu,Eunice; Ngichabe,Christopher; Olubayo,Florence; Shibairo,Solomon.
This study was undertaken to characterize the alpha subgroup of the proteobacteria causing the huanglongbing (HLB) disease of citrus from three different ecological zones of Kenya namely the Lower highlands (LH2, LH3, 1800-1900 m above sea level); Upper midlands (UM3, UM4, 1390-1475m), Lower midlands (LM5, LM4, LM3 of 1290-1340-1390m), by isolation and sequencing DNA encoding the L10 and L12 ribosomal proteins and the intergenic region. A 7I6-basepair DNA fragment was amplified and sequenced and consisted of 536 basepairs of DNA encoding the L10 protein, 44 basepairs of DNA intergenic region and 136 basepairs of DNA that partially encodes the L12 protein. Sequences of rpL10/L12 protein genes from Kenyan strains were 98% and 81% similar to the South African...
Tipo: Journal article
Palavras-chave: Citrus greening disease; DNA sequencing; Intergenic regions; Phylogeny; Ribosomal protein genes.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200005

Utilization and biodegradation of starch stillage (distillery wastewater)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Krzywonos,Malgorzata; Cibis,Edmund; Miskiewicz,Tadeusz; Ryznar-Luty,Agnieszka.
Stillage (distillery wastewater) is the main by-product originating in distilleries, and its volume is approximately 10 times that of ethanol produced. It is not surprising that the utilization of the stillage raises serious problems, and that many attempts have been made all over the world to solve them. In Poland most of the ethanol (about 90%) is produced from starch-based feedstocks, i.e. grains and potatoes. Starch feedstocks are widely used for spirit production also in other European countries, as well as outside Europe. The manuscript provides an overview of global fuel ethanol production and information on methods used for starch-based stillage biodegradation and utilization. The methods presented in this paper have been classified into two major...
Tipo: Journal article
Palavras-chave: Biodegradation; Distillery; Ethanol; Starch stillage; Utilization.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000100006

Simultaneous saccharification and fermentation process of different cellulosic substrates using a recombinant Saccharomyces cerevisiae harbouring the &amp;#946;-glucosidase gene
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ferreira,Verônica; Faber,Mariana de Oliveira; Mesquita,Sabrina da Silva; Pereira Jr,Nei.
In Brazil, the production of ethanol from sugarcane produces large amounts of lignocellulosic residues (bagasse and straw), which have been driving research and development for the production of second generation ethanol. In the present work, a recombinant Saccharomyces cerevisiae strain expressing the &amp;#946;-glucosidase gene from Humicola grisea was used for ethanol production from three different cellulosic sources by simultaneous saccharification and fermentation. Initially, a enzymatic pre-hydrolysis step was done with a solid:liquid ratio of 1:4, and an enzymatic load of 25 filter paper activity (FPU).g-1 of cellulosic substrate. Using sugarcane bagasse pretreated cellulignin, crystalline cellulose and carboxymethyl cellulose, 51.7 g L-1, 41.7 g...
Tipo: Journal article
Palavras-chave: Bioethanol; Lignocellulosic biomass; Sugarcane bagasse derived cellulignin.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000200005

Quantitative real-time PCR method to detect changes in specific transcript and total RNA amounts
Provedor de dados: Electronic Journal of Biotechnology
Autores: Baek,Kwang-Hyun; Skinner,Daniel Z.
Quantitative real-time PCR (qRT-PCR), used in conjunction with reverse transcriptase, has been applied to the determination of the number of copies of a transcript per unit mass of RNA, but did not indicate any change in the amount of total RNA per mass of tissue. In the present work, we described a simple method to use qRT-PCR to estimate the change in the amount of total RNA per unit mass of wheat (Triticum aestivum L.) tissue in response to cold temperature. Three qRT-PCR templates, i.e. control, cold-exposed, and one of RNA extracted from a sample consisting of equal masses of control and cold-exposed tissue, were analyzed. The number of copies of target transcript per unit mass of RNA was estimated from the three samples using standard qRT-PCR...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000100008

Novel protocol to identify true hybrids in normal oleate x high oleate crosses in peanut
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Chuan Tang; Yu,Shan Lin; Zhang,Shu Wei; Wang,Xiu Zhen; Tang,Yue Yi; Zhang,Jian Cheng; Chen,Dian Xu.
A novel hybrid identification protocol was developed for F0:1 peanut seeds resulting from crosses between normal oleate cultivars with wild type FAD2B gene and high oleate genotypes with an A insertion in FAD2B gene. Presence of a series of overlapped peaks in trace file of the PCR product amplified with bF19/R1 primers was an indication of hybridity. This protocol may facilitate high oleate breeding and genetic studies in peanut.
Tipo: Journal article
Palavras-chave: Identification; NIRS; PCR; Peanut; True hybrid.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500018

Enzyme activity and thermostability of a non-specific nuclease from Yersinia enterocolitica subsp. palearctica by site-directed mutagenesis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Yu; Li,Zhen-Hua; Zheng,Wei; Tang,Zhen-Xing; Zhang,Zhi-Liang; Shi,Lu-E.
Background: To identify the critical amino acid residues that contribute to the high enzyme activity and good thermostability of Yersinia enterocolitica subsp. palearctica (Y. NSN), 15 mutants of Y. NSN were obtained by site-directed mutagenesis in this study. And their enzyme activity and thermostability were assayed. Effect of several factors on the enzyme activity and thermostability of Y. NSN, was also investigated. Results: The results showed that the I203F and D264E mutants retained approximately 75% and 70% enzyme activity, respectively, compared to the wild-type enzyme. In addition to the I203F and D264E mutants, the mutant E202A had an obvious influence on the thermostability of Y. NSN. According to the analysis of enzyme activity and...
Tipo: Journal article
Palavras-chave: Factors affecting enzyme activity; Nuclease; Mutation; Mutagenesis; Nucleases without sequence specificity.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600005

Food biotechnology and education
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ramón,Daniel; Diamante,Alicia; Calvo,María Dolores.
It is clear that the future of our children will be marked by the development of two scientific disciplines: computing and biotechnology. Regarding the first, during recent years considerable progress have been done in many countries around the globe aimed at enhancing the teaching in these subjects and, at the same time, encouraging the use of computers in classrooms. On the contrary, training in biotechnology is absent in many secondary schools of the planet. This formative deficiency generates citizens whose opinion on the marketing of biotechnological products is easily manipulated by both defenders and opposers of biotechnology. This situation is of particular relevance when the item in question is food biotechnological applications that provoke an...
Tipo: Journal article
Palavras-chave: Food biotechnology; Genetically modified foods; Public perception; Young consumers.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000500001

Developmental rates of bovine nuclear transfer embryos derived from different fetal non transfected and transfected cells
Provedor de dados: Electronic Journal of Biotechnology
Autores: Felmer D,Ricardo; Arias,María Elena.
Since the first successful somatic cell nuclear transfer (SCNT) experiments were carried out, a number of domestic and agriculture species have been cloned using donor cells derived from different sources and origin. However, differences in nuclear transfer efficiency both in vitro and in vivo have been generally observed. These differences may be accentuated when transgenic cell lines are used as nuclear donors in an attempt to generate transgenic cloned offspring. The present study examined the suitability of cell lines derived from 3 different fetal sources and the effects of genetic manipulation of donor fetal fibroblasts with a red fluorescent plasmid, on the in vitro developmental potential and quality of nuclear transfer derived bovine embryos. We...
Tipo: Journal article
Palavras-chave: Bovine embryos; Fetal fibroblasts; Nuclear transfer; Transfected cells.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300005

Organogenesis from leaf and internode explants of Ophiorrhiza prostrata, an anticancer drug (camptothecin) producing plant
Provedor de dados: Electronic Journal of Biotechnology
Autores: Shahanaz Beegum,A; Poulose Martin,Kottackal; Zhang,Chun-Lai; Nishitha,I. K.; Ligimol,; Slater,Adrian; Madhusoodanan,P. V.
Camptothecin (CPT) analogues and derivatives serve as a novel class of effective anticancer agents that exert their action against DNA topoisomerase I. This paper presents procedures for the rapid, high frequency regeneration of a camptothecin producing plant, Ophiorrhiza prostrata D. Don from leaf and internode explants via shoot organogenesis. The concentrations of plant growth regulators and explant types exhibited discrete roles in the efficacy of shoot induction. N6-benzyladenine (BA) was the most effective cytokinin for the induction of shoots. Murashige and Skoog (MS) medium with 8.87 µM BA and 2.46 µM indole-3-butyric acid (IBA) yielded the highest number of shoots from leaf and internode explants (76.0 and 90.8 shoots respectively). In the case of...
Tipo: Journal article
Palavras-chave: Camptothecin; Medicinal plant; Ophiorrhiza prostrata; Plant growth regulators.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100011

Golgins: coiled-coil-rich proteins associated with the Golgi Complex
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chan,Edward K.L.; Fritzler,Marvin J.
Autoantibodies directed against self-antigens are characteristic features of a number of human diseases. In systemic rheumatic diseases, these include antibodies that react with extracellular molecules; the cell membrane; nuclear and cytoplasmic components. Our laboratories have been interested in understanding autoimmune responses in systemic lupus erythematosus and related disease states and using human autoantibody as molecular probes in studying the cell biology of target antigens. This review summarizes our research efforts in dissecting the autoimmune response to the Golgi complex via expression cloning using human autoantibodies. We have cloned 4 of 5 known Golgi autoantigens that are referred to as golgin-95/GM130, golgin-97, golgin-160/GCP170, and...
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000200001

Assessment of genetic diversity among Pakistani wheat (Triticum aestivum L.) advanced breeding lines using RAPD and SDS-PAGE
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ahmed,Muhammad Farooq; Iqbal,Muhammad; Masood,Muhammad Shahid; Rabbani,Malik Ashiq; Munir,Muhammad.
Genetic diversity was assessed among 32 advanced wheat breeding lines included in the National Uniform Wheat Yield Trials (2006-07) of Pakistan using molecular (DNA) and biochemical (SDS-PAGE) markers. Of the 72 RAPD primers used for initial screening, 15 were found polymorphic. A total of 140 bands (61.4% polymorphic) were generated by the 15 random decamer primers. Genetic similarity coefficients ranged from 0.81 to 0.94 for rainfed and from 0.70 to 0.93 for the normal seeding date group. Cluster analysis using the unweighted pair group method of arithmetic averages (UPGMA) clustered the 32 advanced wheat breeding lines into one major and three small groups. Maximum level of polymorphism (90%) was observed for the primer OPA-05. Lines N9 and N11 showed...
Tipo: Journal article
Palavras-chave: Genetic diversity; Molecular markers; Polymorphism; RAPD; SDS-PAGE; Wheat.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300001

Influence of buffer systems on Trichoderma reesei Rut C-30 morphology and cellulase production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ferreira,Susana M. P.; Duarte,Ana P.; Queiroz,João A.; Domingues,Fernanda C.
The cellulase enzyme production is a key issue in the enzymatic hydrolysis of lignocellulosic materials. Since fungal morphology influences the productivity of fungal fermentations, it is of major importance to well know the fungal behavior during culture for cellulase production. In this work, the influence of medium supplementation, with different buffer systems at two different concentrations and pH conditions, on the morphology of T. reesei Rut C-30 and cellulase production, was investigated. A medium without buffer was used as control. The results suggest that fungal morphology is significantly dependent on the addition of different buffer systems to the nutrient broth. The mycelial morphology shows a clear transition from clumped to pelleted forms in...
Tipo: Journal article
Palavras-chave: Buffer systems; Cellulase; Fungal morphology; Submerged cell growth; Trichoderma reesei Rut C-30.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300008

Can owners afford humanitarian donations in agbiotech - The case of genetically engineered eggplant in India
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kolady,Deepthi; Lesser,William.
Are humanitarian donations in agbiotech economically feasible for the donor? We address this question by conducting an ex ante analysis of genetically engineered (GE) eggplant in India. Our analysis indicates that it is economically viable for a firm to donate the technology for poor farmers&amp;#8217; use by restricting use to open pollinated varieties while selling hybrid verities. By extension, this means of segmenting markets would likely apply in cases where different levels of production technologies are used based on access to market, irrigation, and credit, at least for perishable crops.
Tipo: Journal article
Palavras-chave: Bt eggplant; Market segmentation; Public-private partnership.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200002

The molecular diversity analysis of Auricularia auricula-judae in China by nuclear ribosomal DNA intergenic spacer
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Li; Zhong,Cai-hong; Bian,Yin-bing.
Background: For the crossbreeding of Auricularia auricula-judae, selecting the appropriated parents in hybridization is very important. However, the classification and diversity analysis of A. auricula-judae has been equivocal, due to the similarity of the fruiting body morphology and its susceptibility to environmental influences. For this purpose, the molecular diversity of 32 A. auricula-judae commercial cultivars in China was analyzed by using the nuclear ribosomal DNA intergenic spacer. Results: The complete nuclear rDNA gene complex of A. auricula-judae isolate is 11,210 bp long, and contains the 18S, 5.8S, and 28S rRNA gene as well as the ITS and IGS regions. Based on the sequence data, four more effective primer combinations for the IGS region of...
Tipo: Journal article
Palavras-chave: Gremplasm resource Genetic polymorphism Strain identification Ribosomal RNA genes.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100005

Production of heterologous cutinases by E. coli and improved enzyme formulation for application on plastic degradation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gomes,Daniela S; Matamá,Teresa; Cavaco-Paulo,Artur; Campos-Takaki,Galba M; Salgueiro,Alexandra A.
Background: The hydrolytic action of cutinases has been applied to the degradation of plastics. Polyethylene terephthalate (PET) have long half-life which constitutes a major problem for their treatment as urban solid residues. The aim of this work was to characterize and to improve stable the enzyme to optimize the process of degradation using enzymatic hydrolysis of PET by recombinant cutinases. Results: The wild type form of cutinase from Fusarium solani pisi and its C-terminal fusion to cellulose binding domain N1 from Cellulomonas fimi were produced by genetically modified Escherichia coli. The maximum activity of cutinases produced in Lactose Broth in the presence of ampicillin and isopropyl &amp;#946;-D-1-thiogalactopyranoside (IPTG) was 1.4 IU/mL....
Tipo: Journal article
Palavras-chave: Cutinase; Environmental application; Poly(ethylene terephthalate).
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500003

Antiproliferative evaluation of tall-oil docosanol and tetracosanol over CHO-K1 and human melanoma cells
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vergara,Mauricio; Olivares,Araceli; Altamirano,Claudia.
Background Polycosanols derived from plant species have traditionally been used in medicine as antiproliferative agents for treating various viruses (primarily the herpes simplex virus). However, few studies have studied their effects on hyperproliferative cell lines. In this work, the antiproliferative capacity of polycosanols from tall-oil pitch, obtained from black liquor soaps in the kraft pulping process of cellulose (specifically from Pinus radiata, Pinus taede, and Eucalyptus globulus), was evaluated on CHO-K1 and CRL-1974 human melanoma cell lines. Results The proliferative capacities and cell viabilities were measured for 72 and 140 h, respectively. Treatment with docosanol produced differential effects on the CHO-K1 and human melanoma cells and...
Tipo: Journal article
Palavras-chave: CHO-K1 cells; Growth-arrested; Human melanoma cells; Polycosanols.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400006

Extraction optimization of total triterpenoids from Jatropha curcas leaves using response surface methodology and evaluations of their antimicrobial and antioxidant capacities
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wei,Lei; Zhang,Wei; Yin,Li; Yan,Fang; Xu,Ying; Chen,Fang.
Background Triterpenoids are multifunctional secondary metabolites in plants. But little information is available concerning the actual yield, optimal extraction method and pharmacologic activity with regard to triterpenoids from Jatropha curcas leaves (TJL). Hence, response surface methodology (RSM) was used to optimize the extraction parameters. The effects of three independent variables, namely liquid-to-solid ratio, ethanol concentration and extraction time on TJL yield were investigated. TJL obtained by silica column chromatography was tested against bacterial and fungal species relevant to oral disease and wounds through broth microdilution. Antioxidant activity was assessed using the 2,2-diphenyl-2-picrylhydrazyl and...
Tipo: Journal article
Palavras-chave: Box-Behnken design; Radical scavenging activity; Ultrasound-assistant extraction.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200005

The effects of ethylene on the HCl-extractability of trace elements during soybean seed germination
Provedor de dados: Electronic Journal of Biotechnology
Autores: Liu,Chunming; Zhao,Yixin; Liu,Jianfeng; Gen,Wanting; Cheng,Yunqing.
Background Ethylene is capable of promoting seed germination in some plant species. Mobilization of metals such as Fe, Cu, Mn, and Zn in mature seeds takes place when seeds are germinating. However, whether ethylene is involved in the regulation of soybean seed germination and metal element mobilization during early seed germination stage remains unknown. In the present study, seeds were treated with ethylene synthesis inhibitor aminoethoxyvinylglycine (AVG) and ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), and double distilled H2O (ddH(2)0) treatment was used as control. Ethylene emission, ACC synthase (ACS) expression, ACS enzyme activity and Ca, Zn, Mn, Cu and Fe content in hypocotyls were qualified to analyze the relationship between...
Tipo: Journal article
Palavras-chave: ACC synthase; Bioavailability; Ethylene; Metallic elements; Seed germination; Soybean.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500001

Selection of bioantagonistic bacteria to be used in biological control of Rhizoctonia solani in tomato
Provedor de dados: Electronic Journal of Biotechnology
Autores: Montealegre,Jaime R.; Reyes,Rodrigo; Pérez,Luz María; Herrera,Rodrigo; Silva,Polyana; Besoain,Ximena.
Bacteria from the rhizoplane and surrounding soil of healthy and Rhizoctonia solani diseased tomato plants, cropped in greenhouse of the V Region of Chile, were collected. The best bacterial strains, based on their ability to control development of three R. solani isolates (identified as belonging to the anastomosis groups AG-2-1, AG&amp;#8209;4), were identified as B. subtilis (one isolate) and B. lentimorbus (two different isolates). All bacterial isolates resulted effective for the in vitro control of growth of all R. solani isolates, where the control mechanisms used by the bacteria do not involve the secretion of fungal cell wall hydrolytic enzymes. R. solani AG-2-1 was more sensitive than R. solani AG-4. On the other hand, all bacteria grew well in...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000200006

Comparison of different methods for total RNA extraction from sclerotia of Rhizoctonia solani
Provedor de dados: Electronic Journal of Biotechnology
Autores: Shu,Canwei; Sun,Si; Chen,Jieling; Chen,Jianyi; Zhou,Erxun.
Background Rhizoctonia solani (teleomorph: Thanatephorus cucumeris) is one of the most important pathogens of rice (Oryza sativa L.) that causes severe yield losses in all rice-growing regions. Sclerotia, formed from the aggregation of hyphae, are important structures in the life cycles of R. solani and contain a large quantity of polysaccharides, lipids, proteins and pigments. In order to extract high-quality total RNA from the sclerotia of R. solani, five methods, including E.Z.N.A.&amp;#8482; Fungal RNA Kit, sodium dodecyl sulfate (SDS)-sodium borate, SDS-polyvinylpyrrolidone (PVP), guanidinium thiocyanate (GTC) and modified Trizol, were compared in this study. Results The electrophoresis results showed that it failed to extract total RNA from the...
Tipo: Journal article
Palavras-chave: Polyvinylpyrrolidone; Rhizoctonia solani; RT-PCR; Sclerotia; Sodium dodecyl sulfate; Total RNA extraction.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100009

Xylanolytic enzymes production by Aspergillus niger GS1 from solid-state fermentation on corn stover and their effect on ruminal digestibility
Provedor de dados: Electronic Journal of Biotechnology
Autores: Regalado,Carlos; Vázquez-Obregón,Immer; García-Almendárez,Blanca Estela; Domínguez-Domínguez,Jorge; Aguilera-Barreyro,Araceli; Amaro-Reyes,Aldo.
Hemicellulosic agricultural by-products such as corn stover (CS) are highly available materials which represent an opportunity to develop value added products. Native Aspergillus niger GS1 was used for solid-state fermentation (SSF) on alkali pre-treated CS (ACS) aimed to optimize xylanolytic enzymes production, and their effect on in vitro ruminal and true digestibility of ACS. Enzyme production was empirically modelled using a fractional factorial design 2(9-5), and the resulting significant factors were glucose, yeast extract and two mineral salts, which were arranged in a Draper-Lin optimization design at two levels. Predicted optimum xylanolytic activity of 33.6 U (mg protein)-1 was achieved at 48 hrs of SSF, and was validated by confirmatory...
Tipo: Journal article
Palavras-chave: Aspergillus niger GS1; Corn stover; Digestibility; Solid-state fermentation; Xylanolytic activity.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200009

Elicitation of peroxidase activity in genetically transformed root cultures of Beta vulgaris L.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rudrappa,Thimmaraju; Neelwarne,Bhagyalakshmi; Lakshmanan,Venkatachalam; Reddampalli Venkataramareddy,Sreedhar; Gokare Aswathanarayana,Ravishankar.
Genetically transformed roots of red beet produce copious levels of peroxidase (POD) - a multifunctional enzyme with a number of commercial applications. In an effort to elicit the POD activity, the cultures were treated with biotic elicitors such as dry cell powders of microbial cultures (0.1-0.5% w/v) and the respective culture filtrates (1-5% v/v). Similarly, abiotic elicitors, particularly metal ions (2-8 folds of that present in the nutrient medium), the plant hormone Thidiazuron (at 0.25-1 ppm) and other bio-molecules such as Glutathione (at 0.5-10 mM) and Methyl jasmonate (at 20-100 µM) were used. It was observed that dry cell powder of Candida versatilis significantly elicited the enzyme activity (3.52-fold higher than the control) followed by...
Tipo: Journal article
Palavras-chave: Aspergillus; Calcium; Culture filtrate; Dried cell powder; Elicitor; Glutathione; Methyljasmonate; Rhizophus; Thidiazuron.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500006

Protocol for regeneration in vitro of Arachis hypogaea L
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cucco,María Florencia; Rossi Jaume,Alberto Daniel.
The regeneration of peanut Runner varieties grown in the South of the province of Cordoba, Argentina, was studied to count on a regeneration protocol, which is essential to perform genetic transformation of the plant. The induction of somatic embryos was evaluated in different peanut explants cultivated in Cordoba: cotyledons with and without embryos, epycotils and leaflets, of the Tegua, Nahuel and Florman INTA varieties. The induction medium consisted of MS salts with 30 g.l-1 sucrose, supplemented with the following hormones and herbicides: BAP, Picloram, DMA and 2,4-D. The highest percentage of embryogenic callus was produced cultivating epicotyls with 50 mg.l-1 2,4-D. The embryos obtained produced plantlets which, once acclimatized, reached the...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000200007

Plant prebiotics and human health: Biotechnology to breed prebiotic-rich nutritious food crops
Provedor de dados: Electronic Journal of Biotechnology
Autores: Dwivedi,Sangam; Sahrawat,Kanwar; Puppala,Naveen; Ortiz,Rodomiro.
Microbiota in the gut play essential roles in human health. Prebiotics are non-digestible complex carbohydrates that are fermented in the colon, yielding energy and short chain fatty acids, and selectively promote the growth of Bifidobacteria and Lactobacillae in the gastro-intestinal tract. Fructans and inulin are the best-characterized plant prebiotics. Many vegetable, root and tuber crops as well as some fruit crops are the best-known sources of prebiotic carbohydrates, while the prebiotic-rich grain crops include barley, chickpea, lentil, lupin, and wheat. Some prebiotic-rich crop germplasm have been reported in barley, chickpea, lentil, wheat, yacon, and Jerusalem artichoke. A few major quantitative trait loci and gene-based markers associated with...
Tipo: Journal article
Palavras-chave: Germplasm; Gut microbiota; Human health; Non-digestible fibers; Transgene.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000500008

Characterization of a Gelatin/Chitosan/Hyaluronan scaffold-polymer
Provedor de dados: Electronic Journal of Biotechnology
Autores: Enrione,Javier; Osorio,Fernando; López,Daniel; Weinstein-Oppenheimer,Caroline; Fuentes,Miguel A; Ceriani,Ricardo; Brown,Donald I; Albornoz,Fernando; Sánchez,Elizabeth; Villalobos,Patricio; Somoza,Rodrigo A; Young,Manuel E; Acevedo,Cristian A.
Gelatin, chitosan and hyaluronic acid are natural components used to prepare polymeric scaffold in tissue engineering. The physical properties of these materials confer an appropriate microenvironment for cells, which can be used as a regeneration system for skin and cartilage. In this work, we prepared and characterized a Gelatin/Chitosan/Hyaluronan lyophilized-polymer. Physical properties of lyophilized-polymer changed slightly with moisture, but when polymer was totally hydrated the elasticity changed significantly. Thermophysical characterisation indicated that temperatures higher than 30ºC could modify irreversibly the polymeric matrix probably due to protein denaturation. Besides, we used the polymer as scaffold to prepare a biosynthetic-skin,...
Tipo: Journal article
Palavras-chave: Chitosan; Fibrin; Gelatin; Hyaluronic acid; Scaffold.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500020

Improved growth model for two-stage continuous cultures of Lactobacillus helveticus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bouguettoucha,Abdallah; Balannec,Béatrice; Nacef,Saci; Amrane,Abdeltif.
An unstructured model for growth and lactic acid production during two-stage continuous cultures of Lactobacillus helveticus was previously developed. The Verlhust model was considered to describe growth kinetics. Production models was based on modified Luedeking-Piret expressions involving an inhibitory effect for the first stage (seed culture) and a nutritional limitation effect for the second stage (culture). To account for the decrease of the biomass concentration observed in the second stage, the dilution rate Dc was replaced by an exponential term of the dilution rate &lt;img border=0 width=84 height=36 src="http://fbpe/img/ejb/v13n5/a07/image002.gif" align=middle&gt;in the growth and product relations. Contrarily to the previous model, the important...
Tipo: Journal article
Palavras-chave: Continuous culture; Growth; Lactic acid fermentation; Substrate limitation; Unstructured models.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500007

A new method: measurement of microleakage volume using human, dog and bovine permanent teeth
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yavuz,Izzet; Aydin,Haluk; Ulku,Refik; Kaya,Sadullah; Tumen,Caner.
This study investigates the feasibility of a different new approach to determining the microleakage volume associated with dental restorations (Class V cavity restorated with glass ionomer cement + high copper amalgam) and the relative marginal adaptation deficiency of dog, bovine and human permanent teeth in in vitro conditions. Also researched is the appropriateness of using dog and bovine teeth in in vitro studies rather than human teeth. Our method utilizes the molecular adsorption characteristics of methylene blue. Within the framework of this study, 60 permanent teeth (20 human, 20 dogs and 20 bovine) were used. These groups were evaluated statistically, of which indicated no statistically significant differences (p &gt; 0.05). It was also concluded...
Tipo: Journal article
Palavras-chave: Dye adsorption test; Microleakage; Tooth.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100003

Design and expression of a retro doublet of cecropin with enhanced activity
Provedor de dados: Electronic Journal of Biotechnology
Autores: Díaz,Mauricio; Arenas,Gloria; Marshall,Sergio H.
Novel doublet molecules of cecropin A from Drosophila melanogaster were designed and constructed combining the regular (CECdir) with the inverted (CECret) coding sequence of the standard CEC A1 gene resulting in the following configurations: CECdir-CECret and CECret-CECdir. These two recombinant molecules were generated using a three-primer driven PCR reaction yielding composite single functional aminoacidic molecules with the coding sequences of CECdir linked in frame with the coding sequence of CECret and vice versa. In order to obtain these constructions, a retropeptide DNA-coding sequence was chemically synthesized to match the expected polarity of the newly generated CECret sequence. Both doublet antimicrobial peptides (drAMPs) were cloned in the T7...
Tipo: Journal article
Palavras-chave: Antimicrobial peptides; Escherichia coli; Expression.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200006

Industrial derivative of tallow: a promising renewable substrate for microbial lipid, single-cell protein and lipase production by Yarrowia lipolytica
Provedor de dados: Electronic Journal of Biotechnology
Autores: Papanikolaou,Seraphim; Chevalot,Isabelle; Galiotou-Panayotou,Maria; Komaitis,Michael; Marc,Ivan; Aggelis,George.
The aim of the present study was to assess the potential of valorisation of a solid industrial derivative of tallow, composed of saturated free-fatty acids ("stearin"), by fermentations carried out by the yeast Yarrowia lipolytica ACA-DC 50109 in order to produce microbial lipid, biomass and extra-cellular lipase. High quantities of biomass were produced (biomass yield of around 1.1 ± 0.1 g of total biomass produced per g of fat consumed) when the organism was grown in shake flasks, regardless of the concentration of extra-cellular nitrogen present. Cellular lipids accumulated in notable quantities regardless of the nitrogen availability of the medium, though this process was clearly favoured at high initial fat and low initial nitrogen concentrations. The...
Tipo: Journal article
Palavras-chave: Lipase; Microbial lipids; Single-cell protein; Tallow; Yarrowia lipolytica.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300010

The genetic diversity of Sardinian myrtle (Myrtus communis L.) populations
Provedor de dados: Electronic Journal of Biotechnology
Autores: Melito,Sara; Chessa,Innocenza; Erre,Patrizia; Podani,János; Mulas,Maurizio.
Background: The myrtle (Myrtus communis) is a common shrub widespread in the Mediterranean Basin. Its fruit and leaves exhibit antioxidant, antibacterial and antifungal properties, and are used for their content of essential oils and for their medicinal properties, but most commonly as an ingredient in locally made liquor. The uncontrolled exploitation of natural stands has reduced both the species' geographical coverage and the size of individual populations. The selection of genotypes for controlled cultivation requires a characterization of the genetic diversity present both within and between populations. Results: Genotypic variation was evaluated using ISSR profiling and genetic diversity characterized using standard population genetics approaches....
Tipo: Journal article
Palavras-chave: Domestication; Genetic structure; Germplasm; ISSR genotyping.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600007

One-pot synthesis of graphene-chitosan nanocomposite modified carbon paste electrode for selective determination of dopamine
Provedor de dados: Electronic Journal of Biotechnology
Autores: Liu,Chang; Zhang,Jing; Yifeng,E; Yue,Jingli; Chen,Lianshan; Li,Donghui.
Background A simple, rapid, low-cost and environmentally friendly method was developed to determine dopamine (DA) in the presence of ascorbic (AA) and uric acid (UA) based on a novel technique to prepare a graphene-chitosan (GR-CS) nanocomposite and modify it on the surface of carbon paste electrode (CPE). For our design, CS acts as a media to disperse and stabilize GR, and then GR plays a key role to selective and sensitive determination of DA. Results Under physiological conditions, the linear range for dopamine was determined from 1 × 10- 4 to 2 × 10- 7 mol/L with a good correlation coefficient of 0.9961 in the presence of 1000-fold interference of AA and UA. The detection limit was estimated to be 9.82 × 10- 8 mol/L (S/N = 3). In order to study the...
Tipo: Journal article
Palavras-chave: Dopamine; Selective determination; Surface modification of carbon paste electrode; Technique of one-pot synthesis.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000400007

Oxidation of volatile reduced sulphur compounds in biotrickling filter inoculated with Thiobacillus thioparus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cáceres,Manuel; Morales,Marjorie; San Martín,Ricardo; Urrutia,Homero; Aroca,Germán.
Reduced volatile sulphur compounds generate an impact on the environment, because of the bad smell and its low odour threshold. Compared with the existing physicochemical technologies for their elimination, biotrickling filters are an economically and environmentally sustainable alternative. Usually mixed cultures of microorganisms are used for inoculating biotrickling filters, in this case a pure culture of Thiobacillus thioparus is used for generating a biofilm, allowing to measure its capacity for the oxidation of four volatile reduced sulphur compounds: hydrogen sulphide, dimethyl sulphide, methyl mercaptan and dimethyl disulphide, using a residence time of 0.033 hrs. The viable cells of the biofilm were quantified by epifluorescence microscopy,...
Tipo: Journal article
Palavras-chave: Biofiltration; Odour removal; Volatile sulphur reduced compounds.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500011

Network models in the study of metabolism
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rodríguez,Arsenio; Infante,Diogenes.
The systematic study of the genetic fingerprint (genomics) and the biochemistry (metabolites) that goes with a specific cellular process requires the characterization of all the small molecules that form the profile of metabolites and the associated genes. The metabolome represents the collection of all the metabolites during certain process in an organism. The transcriptome represents the gene expression profile, all the messengers RNA in a defined condition. Then to understand the whole process, the studies of metabolites must be accompanied with studies of the gene expression, hence the metabolome must be accompanied by the transcriptome, so we can identify genes and metabolites whose synthesis is induced by a specific process, an infection or stress....
Tipo: Journal article
Palavras-chave: Graph theory; Metabolic networks; Metabolomic.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400011

Resistance to freezing in three Eucalyptus globulus Labill subspecies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Moraga S.,Priscila; Escobar,René; Valenzuela A.,Sofía.
The resistance to low temperatures was assessed in seedlings of three subspecies of E. globulus (ssp globulus, ssp bicostata and ssp maidenii) of two different provenances. Lethal temperature 50 (LT50) was obtained by measuring the electrolytic conductivity, nucleation and freezing temperatures were obtained by thermal analysis and the total soluble carbohydrates concentration was determined through the phenol-sulphuric method. Results showed that the most resistant provenance corresponded to Bolaro Mountain of ssp maidenii with a LT50 lower than -9&amp;ordm;C. The provenance Moogora of ssp globulus, had a LT50 of -8.47&amp;ordm;C, which situates it, as the second most resistant to low temperatures. According to the nucleation and freezing temperatures,...
Tipo: Journal article
Palavras-chave: Cold resistance; Ssp bicostata; Ssp globulus; Ssp maidenii.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300026

Biotransformation of anthracene and fluoranthene by Absidia fusca Linnemann
Provedor de dados: Electronic Journal of Biotechnology
Autores: Villemain,Danièle; Guiraud,Pascale; Bordjiba,Ouahiba; Steiman,Régine.
A strain of Absidia fusca was isolated from a pesticide-contaminated soil (Annaba, Algeria). The biotransformation capability of this strain towards two polycyclic aromatic hydrocarbons (PAHs): anthracene and fluoranthene was compared to that exhibited by another strain of A. fusca isolated from a non-contaminated milieu and considered as a control. The results obtained were statistically analyzed and showed that the strain isolated from the contaminated soil was more efficient than the control to remove anthracene from the medium, during all the kinetics (90% removed versus 45% after 24 hrs). Concerning fluoranthene, the amount removed by both strains was very high during the first 24 hrs however the control strain was slightly more efficient (94% versus...
Tipo: Journal article
Palavras-chave: Absidia fusca; Anthracene; Biodegradation; Fluoranthene; Kinetics.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200004

The application of polymerized lipid vesicles as colorimetric biosensors for real-time detection of pathogens in drinking water
Provedor de dados: Electronic Journal of Biotechnology
Autores: Villalobos,Patricio; Chávez,María Isabel; Olguín,Yusser; Sánchez,Elizabeth; Valdés,Erika; Galindo,Raúl; Young,Manuel E.
The inadequate treatments given to the served waste water which are disposal to the rivers and sea coast are the major sources of faecal Microorganisms and enteric bacterial pathogens. They are among the most serious effects of water pollution bringing risks on public health. None of the current methods for detection of pathogens offer real-time on site solutions, are capable of delivering a simple visual detection signal, or can be easily instrumented as an indicator of the presence of a pathogen in water. The use of lipid vesicles incorporating Polydiacetylenes (PDAs) for the development of biosensors for &amp;#147;real-time&amp;#148; detection of pathogens has become an alternative, due to its potential for simple colorimetric response against harmful...
Tipo: Journal article
Palavras-chave: Bacterial detection; Biosensors; Lipid vesicles; PDA.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000100004

Industrial and biotechnological applications of ligninolytic enzymes of the basidiomycota: A review
Provedor de dados: Electronic Journal of Biotechnology
Autores: Maciel,Márcia Jaqueline Mendonça; Silva,Ademir Castro e; Ribeiro,Helena Camarão Telles.
Ligninolytic enzymes of the basidiomycetes play a crucial role in the global carbon cycle. The demand for application of ligninolytic enzymes complexes of white-rot fungi in industry and biotechnology is ever increasing due to their use in a variety of processes. Ligninolytic enzymes have potential applications in a large number of fields, including the chemical, fuel, food, agricultural, paper, textile, cosmetic industrial sectors and more. This ligninolytic system of white-rot fungi is also directly involved in the degradation of various xenobiotic compounds and dyes. Their capacities to remove xenobiotic substances and produce polymeric products make them a useful tool for bioremediation purposes. This paper reviews the applications of ligninolytic...
Tipo: Journal article
Palavras-chave: Laccase; Lignin peroxidase; Manganese peroxidase; White-rot fungi.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600014

Production of ethanol from mesquite (Prosopis juliflora (SW) D.C.) pods mash by Zymomonas mobilis and Saccharomyces cerevisiae
Provedor de dados: Electronic Journal of Biotechnology
Autores: da Silva,Celiane Gomes Maia; Stamford,Tânia Lúcia Montenegro; de Andrade,Samara Alvachian Cardoso; de Souza,Evandro Leite; de Araújo,Janete Magali.
This study aimed to assess the use of mesquite pods hydrated mash as biomass for the growth of Saccharomyces cerevisiae UFEPEDA-1012 and Zymomonas mobilis UFEPEDA-205 and for ethanol production using a submerged fermentation. A 2³ factorial design was used to analyze the effects of the type of microorganism, time of fermentation and condition of cultivation on the ethanol production in mesquite pods mash (30 g 100 mL-1). From the obtained results the hydrated mesquite pods mash presented as a good substrate for the growth of S. cerevisiae and Z. mobilis in comparison to the standard media. The effect that most affected the ethanol production was the type of microorganism. The highest ethanol concentration (141.1 gL-1) was found when Z. mobilis was...
Tipo: Journal article
Palavras-chave: Ethanol; Mesquite; Saccharomyces cerevisiae; Zymomonas mobilis.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500012

Modeling the kinetics of pyrite ash biodesulfurization by Saccharomyces cerevisiae and Acetobacter aceti in liquid state bioreactors
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ermurat,Yakup.
Background: Modeling the kinetics of the biodesulphurization bioprocess for the refining of pyrite ash by Saccharomyces cerevisiae and Acetobacter aceti have been studied in batch-type liquid- state bioreactors. Results: The biodesulphurization experiments were performed at varying temperatures of 25ºC, 30ºC and 35ºC for eight weeks. Glucose, acetic acid and ethyl alcohol were used in the incubation media as substrates and acid sources. pH and oxidation reduction potential (ORP) observations have been determined weekly and the dissolved sulphur was measured at the end of the eight weeks trials. An equation calculating pH was derived from the iron oxidation reaction containing the ferric to ferrous iron [Fe+3/Fe+2] ratio as a variable. The Michaelis-Menten...
Tipo: Journal article
Palavras-chave: Acetobacter aceti biodesulfurization kinetics; Modeling pyrite ash Saccharomyces cerevisiae.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000200004

Utilization of genes encoding osmoprotectants in transgenic plants for enhanced abiotic stress tolerance
Provedor de dados: Electronic Journal of Biotechnology
Autores: Khan,Mohammad Sayyar; Ahmad,Dawood; Khan,Muhammad Adil.
Global agriculture in the context of growing and expanding populations is under huge pressure to provide increased food, feed, and fiber. The recent phenomenon of climate change has further added fuel to the fire. It has been practically established now that the global temperature has been on the increase with associated fluctuations in annual rainfall regimes, and the resultant drought and flood events and increasing soil and water salinization. These challenges would be met with the introduction and utilization of new technologies coupled with conventional approaches. In recent years, transgenic technology has been proved very effective in terms of production of improved varieties of crop plants, resistant to biotic stresses. The abiotic stresses such as...
Tipo: Journal article
Palavras-chave: Osmoprotectants; Salt stress; Tolerance; Transgenic plants.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400001

Evaluating kinetic and physiological features of rCHO-K1 cells cultured on microcarriers for production of a recombinant metalloprotease/disintegrin
Provedor de dados: Electronic Journal of Biotechnology
Autores: Swiech,Kamilla; da Silva,Gracinda M.C; Zangirolami,Teresa C; Iemma,Mônica R.C; Selistre-de-Araújo,Heloísa S; Suazo,Cláudio A.T.
We present kinetic and physiological data regarding the culturing of rCHO-K1 cells on various microcarriers, to evaluate the potential of this culture strategy for mass production of these cells and expression of a recombinant disintegrin. Cultures were performed in 500 mL spinner flasks in DMEM culture medium with 10% v/v fetal calf serum, gently shaken at 37ºC, pH 7.4, in a 10% v/v CO2 atmosphere. The following values were obtained, respectively, for the adhesion time-constant Ka (h) and specific growth rate &amp;#956;max (d-1) on each microcarrier: Cytodex 1 (0.91, 0.45), Cultispher S (0.28, 0.34), Immobasil FS (0.85, 0.52) and Pronectin F (5.12, 0.67). Metabolic characteristics showed some variation among the cultures with the four microcarriers, the...
Tipo: Journal article
Palavras-chave: Adhesion; Animal cell; CHO-K1; Growth; Microcarrier; Recombinant disintegrin.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200004

Effects of fermentation temperature on the composition of beer volatile compounds, organoleptic quality and spent yeast density
Provedor de dados: Electronic Journal of Biotechnology
Autores: Olaniran,Ademola O; Maharaj,Yushir R; Pillay,Balakrishna.
Production of good quality beer is dependent largely on the fermentation temperature and yeast strains employed during the brewing process, among others. In this study, effects of fermentation temperatures and yeast strain type on beer quality and spent yeast density produced after wort fermentation by two commercial yeast strains were investigated. Beer samples were assessed for colour, clarity and foam head stability using standard methods, whilst the compositions and concentration of Beer Volatile Compounds (BVCs) produced were assessed using GC-MS. The spent yeast density, measured as dry cell weight, ranged between 1.84 - 3.157 mg/ml for both yeast strains with the highest yield obtained at room temperature fermentation. A peak viable population of...
Tipo: Journal article
Palavras-chave: Beer volatile compounds; Fermentation temperature; Organoleptic quality; Spent yeast density.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200005

The accuracy of protein structure alignment servers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Aslam,Naeem; Nadeem,Asif; Babar,Masroor Ellahi; Pervez,Muhammad Tariq; Aslam,Muhammad; Naveed,Nasir; Hussain,Tanveer; Shehzad,Wasim; Wasim,Muhammad; Bao,Zhang; Javed,Maryam.
Background: Protein structural alignment is one of the most fundamental and crucial areas of research in the domain of computational structural biology. Comparison of a protein structure with known structures helps to classify it as a new or belonging to a known group of proteins. This, in turn, is useful to determine the function of protein, its evolutionary relationship with other protein molecules and grasping principles underlying protein architecture and folding. Results: A large number of protein structure alignment methods are available. Each protein structure alignment tool has its own strengths and weaknesses that need to be highlighted. We compared and presented results ofsix most popular and publically available servers for protein structure...
Tipo: Journal article
Palavras-chave: Comparative study; Protein structure alignment tools; Web based servers.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000200002

Retroviral-mediated overexpression of human bone morphogenetic protein 2 affects human mesenchymal stem cells during monolayer proliferation: A cautionary note
Provedor de dados: Electronic Journal of Biotechnology
Autores: Neumann,Alexander J; Alini,Mauro; Archer,Charles W; Stoddart,Martin J.
Background: Retroviral vectors are commonly used for gene transfer applications and they represent an effective way to provide a sustained delivery of a bioactive factor in basic research and tissue engineering applications. Cells that have been transduced with retroviral vectors ex vivo are usually amplified on tissue culture plastic, for a prolonged period of time, in order to obtain sufficient cell numbers prior to the experiment of interest. However, the effect of the transgene product on the transduced cells, during this period of time, is rarely, if ever, investigated. The current study investigated if transduction with a VSG.G pseudotyped retroviral vector expressing human bone morphogenetic protein 2 (Rv.BMP-2) influences the gene expression...
Tipo: Journal article
Palavras-chave: Constitutive expression; Controls; Gene transfer; Monolayer expansion; Retrovirus.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000200007

Ethanol induction of laccase depends on nitrogen conditions of Pycnoporus sanguineus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hernández,Christian A; Sandoval,Norma; Mallerman,Julieta; García-Pérez,José Antonio; Farnet,Anne-Marie; Perraud-Gaime,Isabelle; Alarcón,Enrique.
Background Ethanol has been pointed out as a laccase inducer. However, there are controversial reports about its efficiency with some fungi. In this study, we hypothesized that ethanol laccase induced in Pycnoporus sanguineus depends on nitrogen nutriment conditions. To prove this, we assessed laccase production in submerged cultures of P. sanguineus, with different nitrogen concentrations and with, or without ethanol added in a factorial designed experiment. Results In order to analyze the effects of factors on the response variables, a factorial ANOVA, and response-surface models were performed. It was found that the nitrogen source was the main factor that affected laccase production in P. sanguineus. The treatments with yeast extract (2 g/L) and...
Tipo: Journal article
Palavras-chave: Enzyme production; Fungal metabolism; Phenoloxidases; Urea; Yeast extract.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400012

Characterization of the antiyeast compound and probiotic properties of a starter Lactobacillus plantarum DW3 for possible use in fermented plant beverages
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kantachote,Duangporn; Prachyakij,Pakorn; Charernjiratrakul,Wilawan; Ongsakul,Metta; Duangjitcharoen,Yodsawee; Chaiyasut,Chaiyavat; Nitoda,Teruhiko; Kanzaki,Hiroshi.
Lactobacillus plantarum DW3 produced antifungal compounds that inhibited the growth of Rhodotorula mucilaginosa DKA, contaminating yeast in fermented plant beverages (FPBs) and various potential human pathogens. Phenyllactic acid (PLA) identified by gas chromatography- mass spectrometry (GC-MS) was produced at 31 mg/L PLA in MRS medium and 5 mg/ml inhibited growth of the target yeast in vitro by 90%. Other inhibitors were also present but not specifically identified. Results of in vitro tests showed that DW3 also had probiotic properties as it survived various human biological barriers resistance to pH 3, bile salts, growth without vitamin B12 and the presence and absence of oxygen. Its inhibitory effect against food borne pathogenic bacteria and spoilage...
Tipo: Journal article
Palavras-chave: Fermented plant beverage; Lactobacillus plantarum; Phenyllactic acid; Probiotics; Rhodotorula mucilaginosa; Weight control.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500002

New stereoisomeric derivatives of jasmonic acid generated by biotransformation with the fungus Gibberella fujikuroi affect the viability of human cancer cells
Provedor de dados: Electronic Journal of Biotechnology
Autores: Carvajal,Marcela; Espinoza,Luis; Caggia,Silvia; Cardile,Venera; Garbarino,Juan A; Peña-Cortés,Hugo; Russo,Alessandra.
Background: Several studies have shown that (-)-Jasmonic acid, (+)-7-iso-Jasmonic acid and its methyl ester, methyl jasmonate, have anti-cancer activity in vitro and in vivo, exhibiting selective cytotoxicity towards cancer cells. The degree of activity of these molecules is strongly related to their stereochemistry. The biotransformation of known compounds, natural or synthesized, related to interesting biological activities, generates new molecules displaying new improved properties compared with the original ones, increasing its value and providing new more effective products. Therefore, based on the above rationales and observations, in this work a biotransformation protocol to modify the chemical structure of the plant hormone jasmonic acid by using...
Tipo: Journal article
Palavras-chave: Apoptosis; Biotransformations; Cancer cells; Cell vitality; Gibberella fujikuroi; Jasmonic acid.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200007

Constructed wetlands for domestic wastewater treatment in a Mediterranean climate region in Chile
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mancilla Villalobos,Rodrigo; Zúñiga,Jimena; Salgado,Eduardo; Schiappacasse,Maria Cristina; Chamy Maggi,Rolando.
Background: Constructed wetlands are a promising, cheap and effective wastewater treatment in small communities. The studies on these systems have been reported mainly from cold, tropical or subtropical climate regions. In this work we constructed a pilot plant with six horizontal subsurface flow constructed wetlands (HSSF CWs) with a surface area of 2 m² and a depth of 0.6 m each, planted with Typha latifolia or Scirpus sp., and filled with gravel (G) or fine gravel (FG) of 2.8 and 1.2 cm of diameter respectively, continuously fed with raw domestic wastewater. This experimental setup was evaluated over 280 days for the removal of organic matter and nutrients in a Mediterranean climate, near Valparaíso, Chile. The removal of total COD, NH4+-N and PO4-3-P...
Tipo: Journal article
Palavras-chave: Constructed wetlands; Domestic wastewater treatment; Horizontal subsurface flow system; Mediterranean climate.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400005

Polymorphisms of the bovine chemokine receptor-like 1 gene and their associations with meat quality traits in Qinchuan cattle (Bos taurus)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhan,Xiaoli; Jiang,Bijie; Ma,Xianghui; Fu,Changzhen; Zan,Linsen.
Background: We investigated the polymorphisms of the bovine chemokine receptor-like 1(CMKLR1) gene. The coding region of CMKLR1 was screened in Qinchuan cattle by PCR-RFLP technology. Results: In this study, we discovered two single nucleotide polymorphisms (SNPs) (264G &gt; C and 762C &gt; T) in the coding region of the CMKLR1 gene. Hence, we described the BmgT120l and Pdm1 PCR-RFLP methods for detecting the 64G &gt; C and 762C &gt; T mutations, respectively. PCR-RFLP and sequencing were used to analyze the two loci of CMKLR1 gene in 324 individuals, which were randomly selected from breeding populations. Furthermore, meat quality traits in another 80 Qinchuan individuals were analyzed by the comparison between the genotypes and their phenotypic data....
Tipo: Journal article
Palavras-chave: CMKLR1 gene; Meat quality traits; PCR-RFLP; Qinchuan cattle; SNP.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000100003

Development of potency assays for a plasmid containing vascular endothelial growth factor 2
Provedor de dados: Electronic Journal of Biotechnology
Autores: Huang,Li-chun; Chin,Emily; Chiang,Yawen L.
We have developed analytical methods to measure the biological functions of pVGI.1(VEGF2), a naked plasmid DNA product containing vascular endothelial growth factor 2 used in clinical trials for coronary artery diseases (CAD) and peripheral artery diseases (PAD). After being injected into muscles, vascular endothelial growth factor 2 (VEGF-2), presumably expressed in muscle tissues, binds to the endothelial cell receptors VEGFR2 or VEGFR3, triggering the downstream responses including cell proliferation and vascularization. As it is important to make sure clinical material is biological active, we developed a quantitative assay first to measure the receptor binding activity of the pVGI.1(VEGF2) gene product expressed by the transfected host cells, and then...
Tipo: Journal article
Palavras-chave: Cell proliferation; Plasmid DNA; Potency assays; Receptor binding; VEGF-2.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100001

Expression, purification and thermal stability evaluation of an engineered amaranth protein expressed in Escherichia coli
Provedor de dados: Electronic Journal of Biotechnology
Autores: Morales-Camacho,Jocksan I; Paredes-López,Octavio; Espinosa-Hernández,Edgar; Fernández Velasco,Daniel Alejandro; Luna-Suárez,Silvia.
Background: The acidic subunit of amarantin (AAC)-the predominant amaranth seed storage protein-has functional potential and its third variable region (VR) has been modified with antihypertensive peptides to improve this potential. Here, we modified the C-terminal in the fourth VR of AAC by inserting four VY antihypertensive peptides. This modified protein (AACM.4) was expressed in Escherichia coli. In addition, we also recombinantly expressed other derivatives of the amarantin protein. These include: unmodified amarantin acidic subunit (AAC); amarantin acidic subunit modified at the third VR with four VY peptides (AACM.3); and amarantin acidic subunit doubly modified, in the third VR with four VY peptides and in the fourth VR with the RIPP peptide...
Tipo: Journal article
Palavras-chave: Globulin 11S; Protein expression; Protein engineering; Thermal stability.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400007

Molecular dynamics simulations of active site mutants of rat liver arginase
Provedor de dados: Electronic Journal of Biotechnology
Autores: Canales,Mauricio; Westermeyer,Linda; Carvajal,Nelson.
By using molecular dynamics (MD) simulations and crystallographic data for rat liver arginase, the substrate positions in the active sites of native and mutant forms of the enzyme, were compared and correlated with known kinetic consequences of mutations. The mutants compared were His 141&lt;IMG SRC="/content/vol4/issue3/full/6/flecha2.gif" WIDTH=12 HEIGHT=9&gt;Phe and His 141&lt;IMG SRC="/content/vol4/issue3/full/6/flecha2.gif" WIDTH=12 HEIGHT=9&gt;Asn. The simulations show that mutation His141&lt;IMG SRC="/content/vol4/issue3/full/6/flecha2.gif" WIDTH=12 HEIGHT=9&gt;Asn gives the greatest divergence from the atomic coordinates, when compared with the control native enzyme. The mutant Asp128&lt;IMG SRC="/content/vol4/issue3/full/6/flecha2.gif" WIDTH=12...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300010

Bioconversion of agro-industrial wastes for the production of fibrinolytic enzyme from Bacillus halodurans IND18: Purification and biochemical characterization
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vijayaraghavan,Ponnuswamy; Prakash Vincenta,Samuel Gnana; Valan Arasu,Mariadhas; Al-Dhabi,Naif Abdullah.
Background: Agro-wastes were used for the production of fibrinolytic enzyme in solid-state fermentation. The process parameters were optimized to enhance the production of fibrinolytic enzyme from Bacillus halodurans IND18 by statistical approach. The fibrinolytic enzyme was purified, and the properties were studied. Results: A two-level full factorial design was used to screen the significant factors. The factors such as moisture, pH, and peptone were significantly affected enzyme production and these three factors were selected for further optimization using central composite design. The optimum medium for fibrinolytic enzyme production was wheat bran medium containing 1% peptone and 80% moisture with pH 8.32. Under these optimized conditions, the...
Tipo: Journal article
Palavras-chave: Agro-residues; Solid-state fermentation; Statistical approach; Thrombolytic agent.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000200001

Fermentation technologies for the production of exopolysaccharide-synthesizing Lactobacillus rhamnosus concentrated cultures
Provedor de dados: Electronic Journal of Biotechnology
Autores: Champagne,Claude P; Gardner,Nancy J; Lacroix,Christophe.
The exopolysaccharide (EPS)-producing cultures such as Lactobacillus rhamnosus RW-9595M present a challenge for the culture producers because the high viscosity of the fermented growth medium makes it difficult to recover the cells by centrifugation or filtration. This study examined four approaches to reduce viscosity of the medium while producing high cell densities: incubation temperature, extended incubation in the stationary growth phase, production in alginate gel beads and fed-batch fermentation technology. Automated spectrophotometry (AS) was used to study the effects of temperature, pH and lactate level on growth of the strain. In AS assays, there was no significant difference in final maximal biomass production at temperatures ranging between...
Tipo: Journal article
Palavras-chave: Alginate beads; Fed-batch culture; Temperature.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200005

Effect of methyl branching of C8H18 alkanes and water activity on lipase-catalyzed enantioselective esterification of ibuprofen
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gottemukkala,Vijay V; Saripella,Kalyan K; Kadari,Anil K; Neau,Steven H.
The purpose of this research was to study the effect of the methyl branching of a high log P alkane solvent and the water activity in the organic medium on the initial rate and the enantioselectivity of ibuprofen esterification catalyzed by Candida rugosa lipase. Resolution of ibuprofen is important because S-(+)-ibuprofen has the desired pharmacological activity, whereas the R-(-)-enantiomer causes much of the side effects. The Candida rugosa lipase-catalyzed reaction in isooctane at 40ºC and 0.73 water activity gave the best results, both in terms of the initial reaction rate and the enantioselectivity of the reaction. An increase in water activity allowed a higher reaction rate and enantiomeric excess in each of the four solvents. An increase in methyl...
Tipo: Journal article
Palavras-chave: Enantioselective; Esterification; Ibuprofen; Lipase; Solvent-effect; Water activity.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100002

Development and significance of RAPD-SCAR markers for the identification of Litchi chinensis Sonn: by improved RAPD amplification and molecular cloning
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cheng,Jingliang; Long,Yan; Khan,Asaduzzaman; Wei,Chunli; Fu,Shelly; Fu,Junjiang.
Background Analysis of genetic diversity is important for the authentication of a species. Litchi (Litchi chinensis Sonn.) is a subtropical evergreen tree. Recently, L. chinensis has been characterized by an improved random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) analysis. The goal of this study was to develop sequence-characterized amplified region (SCAR) markers from the improved RAPD fragments for the genetic analysis of L. chinensis. Results The improved RAPD fragments from L. chinensis were cloned, sequenced and converted into stable SCAR markers. Sequencing of three cloned RAPD fragments revealed that the clone L7-16 consisted of 222 nucleotides (GenBank accession number KM235222), clone L9-6 consisted of 648...
Tipo: Journal article
Palavras-chave: Genetic authentication; Molecular cloning; Random amplified polymorphic DNA; Sequence-characterized amplified region marker.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100007

Greenhouse evaluation on the performance of heat tolerant transgenic broccoli and genetic diversity analysis using inter simple sequence repeat (ISSR) markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ravanfar,Seyed Ali; Aziz,Maheran Abdul; Shabanimofrad,Mahmoodreza; Samarfard,Samira.
Background: Broccoli, Brassica oleracea subsp. italica is one of the many valuable Brassica species which is still less cultured under in vitro condition. Heat tolerant transgenic and non-transgenic broccoli cv. Green Marvel plantlets with well-developed root system obtained through in vitro culture were transferred into disposable plastic pots containing sterilized potting mixture consisting of (peatgroTM) + coconut dust (2:1) and maintained in a growth chamber. Results: After one month, the hardened plantlets were transferred and maintained in a transgenic greenhouse. After four months of acclimatization in the transgenic greenhouse, the efficacy of HSP101 gene in increasing the heat tolerance of the transgenic broccoli was evaluated. Results showed that...
Tipo: Journal article
Palavras-chave: AtHSP101 gene; Brassica oleracea; ISSR; Transgenic broccoli.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500004

Expression profiles and polymorphism analysis of CDIPT gene on Qinchuan cattle
Provedor de dados: Electronic Journal of Biotechnology
Autores: Fu,Changzhen; Wang,Hong; Li,Yaokun; Wang,Jiali; Cheng,Gong; Wang,Hongbao; Yang,Wucai; Zan,Linsen.
Background CDIPT (CDP-diacylglycerol-inositol 3-phosphatidyltransferase, EC 2.7.8.11) was found on the cytoplasmic side of the Golgi apparatus and the endoplasmic reticulum. It was an integral membrane protein performing the last step in the de novo biosynthesis of phosphatidylinositol (PtdIns). In recent years, PtdIns has been considered to play an essential role in energy metabolism, fatty acid metabolic pathway and intracellular signal transduction in eukaryotic cells. Results In this study, the results of real-time polymerase chain reaction (PCR) showed that the expression of CDIPT gene was remarkably different in diverse tissues. We also detected the polymorphism of bovine CDIPT gene and analyzed its association with body measurement and meat quality...
Tipo: Journal article
Palavras-chave: Body measurement traits; Gene expression; Meat quality traits; PCR-RFLP; SNP.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000400004

Thermotolerant fermenting yeasts for simultaneous saccharification fermentation of lignocellulosic biomass
Provedor de dados: Electronic Journal of Biotechnology
Autores: Choudhary,Jairam; Singh,Surender; Nain,Lata.
Lignocellulosic biomass is the most abundant renewable source of energy that has been widely explored as second-generation biofuel feedstock. Despite more than four decades of research, the process of ethanol production from lignocellulosic (LC) biomass remains economically unfeasible. This is due to the high cost of enzymes, end-product inhibition of enzymes, and the need for cost-intensive inputs associated with a separate hydrolysis and fermentation (SHF) process. Thermotolerant yeast strains that can undergo fermentation at temperatures above 40°C are suitable alternatives for developing the simultaneous saccharification and fermentation (SSF) process to overcome the limitations of SHF. This review describes the various approaches to screen and develop...
Tipo: Journal article
Palavras-chave: Bioethanol; Biofuel; Enzymes; Genome shuffling; Lignocellulosic biomass.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300013

The effect of high concentrations of glycerol on the growth, metabolism and adaptation capacity of Clostridium butyricum DSP1
Provedor de dados: Electronic Journal of Biotechnology
Autores: Szymanowska-Powa&amp;#322;owska,Daria.
Background The production of biofuels from renewable energy sources is one of the most important issues in biotechnology today. The process is known to generate various by-products, for example glycerol that is obtained in the making of biodiesel from rapeseed oil. Crude glycerol may be utilized in many ways, including microbial conversion to 1,3-propanediol. The main drawback of that technology is the use of high concentrations of glycerol, which inhibits the growth of bacterial cells. Results This study investigated the impact of crude glycerol on Clostridium butyricum DSP1 and its ability to adapt to an environment of high osmotic pressure. It was found that a crude glycerol concentration of up to 70 g/L did not have an inhibitory effect on C. butyricum...
Tipo: Journal article
Palavras-chave: Batch culture Clostridium butyricum Environmental stress 1; 3-Propanediol Substrate resistant.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200011

Genetic diversity in two variants of Orobanche gracilis Sm. [var. gracilis and var. deludens (Beck) A. Pujadas] (Orobanchaceae) from different regions of Spain
Provedor de dados: Electronic Journal of Biotechnology
Autores: Román,Belén; Hernández,Rosabell; Pujadas-Salvá,Antonio José; Cubero,José Ignacio; Rubiales,Diego; Satovic,Zlatko.
The pattern of genetic variation among populations of two Orobanche gracilis Sm. taxa (var. gracilis and var. deludens (Beck) A. Pujadas) from Northern and Southern Spain growing on different hosts was analysed using RAPD markers. The diversity analysis within populations revealed a higher level of diversity in the populations from the North when compared to the Southern ones. The results of principal co-ordinate analysis (PCoA) based on Dice distances among samples clearly established the separation of samples according to the taxonomical variety and the geographical origin of each population. The Southern populations of both var. gracilis and var. deludens were more differentiated among them than those of var. gracilis from the North. The analysis of...
Tipo: Journal article
Palavras-chave: AMOVA; Molecular markers; Orobanche gracilis; Parasitic plants; Population genetics.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200006

Practical use of immobilized lysozyme for the remediation process of Escherichia coli in aqueous solution
Provedor de dados: Electronic Journal of Biotechnology
Autores: Alves,Carlucio R; Pimenta,Maria Gardenny R; Vieira,Regine H.S.F; Furtado,Roselayne F; Guedes,Maria Izabel F; Silva,Rui C.B; Assis,Odilio B.G.
The lysozyme enzyme was immobilized on vitreous surface (fragments with diameters of 0.3 and 1.0 mm) for remediation of the microorganism Escherichia coli JM 109 into fresh water and saline solutions with 0.9% NaCl (w/v). Characterization of enzymatic film was carried out by infrared spectroscopy and atomic force microscopy techniques. Bactericide activity of the enzyme was evaluated by spectrophotometric analysis. It was verified that the enzymatic film was strongly coupled with the vitreous surface. The topographic analysis demonstrated that the deposited film was uniform and homogeneous. It was observed bactericide activity of film deposited on vitreous surface with 0.3 mm in fresh and saline solutions. This fact was not verified to vitreous fragments...
Tipo: Journal article
Palavras-chave: Escherichia coli; Lysozyme; Self-assembly.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100015

The use of reactors in biomining processes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Acevedo,Fernando.
Microbial processes applied to mining operations are gaining increasing interest in the last years. Potential and current applications include the mining of gold, copper and other heavy metals, desulfurization of coal and oil, tertiary recovery of oil and biosorption of metal ions. Currently, bacterial leaching of copper and biooxidation of refractory gold concentrates are well-established large-scale processes that are carried on using heaps and tank reactors. Heap operation is simple and adequate to handle large volumes of minerals, but their productivity and yields are limited because of the severe difficulties in exerting an adequate process control. On the other hand, reactors can economically handle moderate volumes of material, but they allow for a...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000300002

Phenolic antioxidants extraction from raspberry wastes assisted by-enzymes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Laroze,Liza; Soto,Carmen; Zúñiga,María Elvira.
The effect of enzymatic hydrolysis on phenolic antioxidant extraction was studied in raspberry solid wastes. This by-product possesses high content of crude fiber (60%) and low values of protein, oil and ash. Raspberry fiber composition suggests that biocatalysts with cellulase, hemicellulase and pectinase activities would be useful for carrying out an enzymatically assisted antioxidant extraction. Hydro-alcoholic extraction was done using different commercial enzymes. Total phenol content and antioxidant activity of enzyme-hydrolyzed residue extracts were measured and compared with those obtained without enzyme application.All biocatalysts evaluated increased soluble solids in comparison to the non-enzymatic control. Among them, Grindamyl and Maxoliva...
Tipo: Journal article
Palavras-chave: Antioxidant activity; Enzymatic extraction; Phenolic compounds.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600011

Expression of Hemagglutinin-Neuraminidase and fusion epitopes of Newcastle Disease Virus in transgenic tobacco
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ghaffar Shahriari,Amir; Bagheri,Abdolreza; Bassami,Mohammad Reza; Malekzadeh-Shafaroudi,Saeid; Afsharifar,Alireza; Niazi,Ali.
Background: Newcastle disease is an important avian infectious disease that brings about vast economic damage for poultry industry. Transgenic plants represent a cost-effective system for the production of therapeutic proteins and are widely used for the production of poultry vaccines. In an attempt to develop a recombinant vaccine, a plant expression binary vector pBI121, containing the genes encoding Hemagglutinin-Neuraminidase (HN) and Fusion (F) epitopes of Newcastle Disease Virus (NDV) under the control of CaMV35S promoter and NOS terminator was constructed and introduced into the tobacco ( Nicotiana tabacum) plant by Agrobacterium-mediated transformation. Results: Putative transgenic plants were screened in a selection medium containing 50 mg/L...
Tipo: Journal article
Palavras-chave: Agrobacterium tumefaciens; ELISA; Recombinant vaccine; Transgenic plants.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400006

Possibility of using apple pomaces in the process of propionic-acetic fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Piwowarek,Kamil; Lipi&amp;#324;ska,Edyta; Ha&amp;#263;-Szyma&amp;#324;czuk,El&amp;#380;bieta.
Background: In 2014, apple production in EU countries amounted to 11.8 million tonnes. A constant increase in the production of these fruits will lead to the accumulation of thousands of tonnes of apple pomace (production waste). The amount of industrial apples is the highest - their proportiononthe market is estimated at 50-60%, of which over 95% is processed into juice. The proportion of pomace in the traditional pressing method accounts for 20% offruits used. Results: Analysis of the growth dynamics of wild strain Propionibacterium freudenreichii T82 in micro-cultures using different carbon sources showed that the highest bacterial growth occurs in an environment with fructose and the most intense biosynthesis of metabolites was found in medium...
Tipo: Journal article
Palavras-chave: Acetic acid; By-products; Carbon sources; Propionibacterium; Propionic acid; Waste materials.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500001

Improvement of myrosinase activity of Aspergillus sp. NR4617 by chemical mutagenesis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rakariyatham,Nuansri; Butr-Indr,Bordin; Niamsup,Hataichanoke; Shank,Lalida.
A myrosinase (thioglucoside glucohydrolase or thioglucosidase, EC 3.2.3.147) producing fungus, Aspergillus sp. NR4617, was newly isolated from decayed soil sample obtained in Thailand and was subjected to single exposure to two chemical mutagens, ethyl methanesulfonate (EMS) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Its myrosinase production was selected on low cost medium prepared from mustard seed cake (Brassica juncea). Studies of production and stability of the enzyme showed that EMS mutagenesis increased myrosinase activity. Aspergillus sp. NR4617E1 produced myrosinase 1.90 U ml-1 at 36 hrs of the cultivation equivalent to 171% of the enzyme production in wild-type. The stability studies revealed that myrosinase from the mutant strains retained...
Tipo: Journal article
Palavras-chave: Allylisothiocyanate; Aspergillus sp.; B-thioglucosidase; Myrosinase; EMS mutagenesis; MNNG mutagenesis.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400005

Strategies for introducing non-radioactive labels during the automated sequence analysis of nucleic acids.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Igloi,Gabor L.
Rapid, large-scale genome as well as diagnostic DNA sequencing projects are, at present, dependent on the use of sensitive automated sequencers that rely on the detection of fluorescent signals. This emission is not an intrinsic property of the biomolecules but is a property of an optical label that must be incorporated before, during or after the sequence specific reaction. The choice of strategy, that is to be reviewed here, is a function of both the chemistry and the enzymology of the system as well as the nature of the fractionation and the physical parameters of the detection. One may differentiate beween the labelling of the primer, incorporation of the label during elongation or base specific termination with labelled terminators. In reviewing the...
Tipo: Journal article
Palavras-chave: Automated sequencing; Non-radioactive labelling; Nucleic acid analysis.
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000100003

Comparative proteome analysis of Brettanomyces bruxellensisunder hydroxycinnamic acid growth
Provedor de dados: Electronic Journal of Biotechnology
Autores: Carmona,Lourdes; Varela,Javier; Godoy,Liliana; Ganga,María Angélica.
Background: Brettanomyces bruxellensis is an important spoilage yeast in the winemaking process. The capacity of this yeast to generate an undesired off-flavor constitutes a significant loss in the Chilean wine industry. Results: The proteomic profile of B. bruxellensis in the presence of p-coumaric acid was determined by 2D gel electrophoresis, gel image analysis and differential spot selection. A set of 41 proteins showed a differential accumulation of ±2 and a p-value &lt;0.0001. The homology sequence analysis was performed using the databases available. Differential proteins belonged to the categories of 'energy production and conversion' and 'amino acid transport and metabolism'. Conclusions: The proteomic profile of B. bruxellensis cultivated in the...
Tipo: Journal article
Palavras-chave: Ethylphenols; Metabolic flux regulation; Proteomics; Spoilage yeast; Wine alterations; Wine industry.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500005

Interaction of Acidithiobacillus ferrooxidans, Rhizobium phaseoli and Rhodotorula sp. in bioleaching process based on Lotka-Volterra model
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zheng,Xuecheng; Li,Dongwei.
Background: Nowadays, leaching-ore bacteria, especially Acidithiobacillus ferrooxidans is widely used to retrieve heavy metals, many researches reflected that extra adding microorganism could promote bioleaching efficiency by different mechanisms, but few of them discussed the interaction between microorganisms and based on growth model. This study aimed to provide theoretical support for the collaborative bioleaching of multiple microorganisms by using the Lotka-Volterra (L-V) model. Results: This study investigated the interaction of Acidithiobacillus ferrooxidans, Rhizobium phaseoli,and Rhodotorula sp. Results showed that the individual growth of the three microorganisms fit the logistic curves. The environmental capacities of A. ferrooxidans, R....
Tipo: Journal article
Palavras-chave: Cell concentration; Collaboration; Commensalism; Mutualism.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400013

Marine genome resource sustainability in Central America
Provedor de dados: Electronic Journal of Biotechnology
Autores: Huete-Pérez,Jorge A; Roberts,Richard J; Quezada,Fernando.
In an effort to raise awareness of the major environmental challenges facing the region’s coastal and marine ecosystems, and to highlight the potential research and socioeconomic benefits of this program, the authors provide summaries of key lectures and conclusions presented in the international conference on Central American Marine Biodiversity and Genomics, in April of 2012, dedicated to “Genomic Archiving and Coastal Marine Biodiversity Exploration, Conservation and Sustainable Development”, and describe the main components of the initiative for the benefit of other actors, stakeholders and donors in the field of marine biodiversity.
Tipo: Journal article
Palavras-chave: Central American Marine Genomic Initiative; Marine biodiversity.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500013

Genetic engineering applications in animal breeding
Provedor de dados: Electronic Journal of Biotechnology
Autores: Montaldo,Hugo H.
This paper discusses the use of genetic engineering applications in animal breeding, including a description of the methods, their potential and current uses and ethical issues. Genetic engineering is the name of a group of techniques used to identify, replicate, modify and transfer the genetic material of cells, tissues or complete organisms. Important applications of genetic engineering in animal breeding are: 1) Marker-assisted selection (MAS). The objective of this technology is to increase disease resistance, productivity and product quality in economically important animals by adding information of DNA markers to phenotypes and genealogies for selection decisions. 2) Transgenesis, the direct transfer of specific genes/alleles between individuals,...
Tipo: Journal article
Palavras-chave: Adult mammalian cloning; Biotechnology; Gene mapping; GMOS; MAS; QTL; Transgenics.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200010

Molecular cloning, characterization and expression analysis of CpCBF2 gene in harvested papaya fruit under temperature stresses
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhu,Xiaoyang; Li,Xueping; Chen,Weixin; Lu,Wangjin; Mao,Jia; Liu,Tongxin.
Background: C-repeat binding factors (CBFs) are transcription factors that regulate the expression of a number of genes related to abiotic stresses. Few CBF genes have been cloned from other plants but no report in papaya. In present study, a full-length cDNA, designated as CpCBF2, was cloned from papaya using in silico cloning and 5&amp;#8217;- rapid amplification cDNA ends (RACE). Sequence analysis was performed to understand the gene function. The expression pattern of CpCBF2 in papaya under low (7ºC) and high temperature (35ºC) stresses was examined using real-time quantitative polymerase chain reaction (RT-qPCR). Results: The full-length cDNA of CpCBF2 was 986-bp, with a 762-bp open reading frame (ORF) encoding a 254 amino acid polypeptide. CpCBF2...
Tipo: Journal article
Palavras-chave: CpCBF2; Gene expression; Papaya; Temperature stresses.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400001

Stability inside hen eggs of a Salmonella enterica serovar Enteritidis bacteriophage
Provedor de dados: Electronic Journal of Biotechnology
Autores: Robeson,James; Valencia,Martina; Retamales,Julio; Borie,Consuelo.
Background: Bacteriophages are viruses that infect bacteria and therefore are widespread in nature. Those that lyse the pathogen Salmonella enterica serovar Enteritidis (SE) should be expected in niches in which this bacterium thrives, among others the avian egg. Furthermore, bacteriophages could remain viable in this milieu. Results: Upon artificially infecting hen eggs with the SE bacteriophage f18 we found that the bacteriophage titer remains stable at least for up to 144 hrs post-infection , both in yolk and albumen at 25ºC. Conclusion: Bacteriophage f18 withstands the physico-chemical conditions of the egg inner milieu and could be considered for SE-controlling measures in the poultry industry.
Tipo: Journal article
Palavras-chave: Bacteriophage; Egg; Enteritidis; Salmonella.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400011

Effect of nitrogen, carbon sources and agitation speed on acetoin production of Bacillus subtilis SF4-3
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tian,Yanjun; Fan,Yixiao; Liu,Jianjun; Zhao,Xiangying; Chen,Wei.
Background: Currently, microbial fermentation method has become the research hotspot for acetoin production. In our previous work, an acetoin-producing strain, Bacillus subtilis SF4-3, was isolated from Japanese traditional fermented food natto. However, its conversion of glucose to acetoin was relatively low. In order to achieve a high-efficient accumulation of acetoin in B. subtilis SF4-3, main medium components and fermentation conditions were evaluated in this work. Results: The by-products analysis showed that there existed reversible transformation between acetoin and 2,3-butanediol that was strictly responsible for acetoin production in B. subtilis SF4-3. The carbon sources, nitrogen sources and agitation speed were determined to play crucial role...
Tipo: Journal article
Palavras-chave: 2; 3-Butanediol Acetoin Bacillus subtilis SF4-3 Reversible transformation.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000100007

Cloning and structural analysis of a cDNA clone encoding glycinin (Gly-1) seed storage protein of peanut
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jain,Ashok K.
A cDNA clone (peanut Gly-1) encoding for glycinin protein was isolated from the immature seeds (from yellow-1 maturity pods) and characterized. The clone spanning a total of 1836 bp, predicted protein of 529 amino acid residues with a calculated mass of 60,447.61 Da. Peanut Gly-1 sequence comparison shows high level of sequence homology with other two peanut glycinin (arachin) genes [Ara h3 (95%) and Ara h4 (94%)] and glycinin (legumin) genes of other legumes such as soybean, broad bean, French bean and pea etc., both at nucleotide (67 to 69%) and amino acid (60 to 63%) levels. The N- and C-terminals of peanut Gly-1 are highly conserved with other glycinin genes; central region of the gene possess three variable regions, which also show conservation with...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300003

Agrobacterium tumefaciens-transient genetic transformation of Habanero pepper (Capsicum chinense Jacq.) leaf explants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Arcos-Ortega,Guadalupe Fabiola; Chan-Kuuk,Rafael Antonio; González-Kantún,Wilma Aracely; Souza-Perera,Ramón; Nakazawa-Ueji,Yumi Elena; Avilés-Berzunza,Elidé; Godoy-Hernández,Gregorio; Lawton,Michael A; Zúñiga Aguilar,José Juan.
Most of the pepper species of the genus Capsicum have been recalcitrant to efficient Agrobacterium tumefaciens-mediated stable or transient, genetic transformation. In the present work, we optimized a protocol for transient transformation of the Habanero pepper (Capsicum chinense Jacq.) through the standardization of several experimental factors. These included the age of the plants, the temperature, the length of co-cultivation, the application of a negative (vacuum) and/or a positive (infiltration) pressure, along with micro injection, the use of acetosyringone during the bacterial culturing, and modification of the pH during the GUS assay to eliminate the endogenous &amp;#946;-glucuronidase activity. The standardized protocol, which yielded nearly 55%...
Tipo: Journal article
Palavras-chave: Cocultivation; GUS assay.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400007

Meat tenderness genetic polymorphisms occurrence and distribution in five Zebu breeds in Mexico
Provedor de dados: Electronic Journal of Biotechnology
Autores: Parra-Bracamonte,Gaspar Manuel; Martínez-González,Juan C; Sifuentes-Rincón,Ana M; Moreno-Medina,Victor R; Ortega-Rivas,Eligio.
Background The Zebu cattle are represented by a diverse group of breeds in México. Traditionally these breeds have been associated with the tough beef characteristic. Validated genetic markers have the potential to be included in marker-assisted selection and management programs in order to improve traits such as beef tenderness. The incidence and distribution of Calpain and Calpastatin polymorphisms strongly associated with beef tenderness were estimated in registered cattle of five Zebu breeds in Mexico. Results A low and in some cases null frequency of favorable C allele of CAPN316 was determined in all breeds. Conversely, a more equilibrated frequency in CAPN4751 and CAST loci was observed. Conclusions Although the relatively low occurrence of...
Tipo: Journal article
Palavras-chave: Calpain; Calpastatin; Frequencies; Genotype; SNP.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500007

Evaluation of fitness in F2 generations of Africa Biofortified Sorghum event 188 and weedy Sorghum bicolor ssp. drummondii
Provedor de dados: Electronic Journal of Biotechnology
Autores: Magomere,Titus; Obukosia,Silas; Albertsen,Mark; Wambugu,Florence; Kamanga,Daniel; Njuguna,Michael; Gaffney,Jim; Zhao,Zuo-Yu; Che,Ping; Aseta,Antony; Kimani,Esther; Mwasame,Evans.
Background: Introgression of transgenes from crops to their wild species may enhance the adaptive advantage and therefore the invasiveness of and weedy forms. The study evaluated the effect of Africa Biofortified Sorghum (ABS) genes from ABS event 188 on the vegetative and reproductive features of the F2 populations derived from crosses with Sorghum bicolor subsp. drummondii. Results: F1 populations were obtained from reciprocal crosses involving ABS event 188 and its null segregant with inbred weedy parents from S. bicolor subsp. drummondii. Four F2 populations and four parental populations were raised in RCBD with 4 replications in a confined field plot for two seasons. Vegetative and reproductive traits were evaluated. The vigour shown in the F2...
Tipo: Journal article
Palavras-chave: Beta-carotene; Heterosis; Transgenics; Phospho-mannose isomarese.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400008

Antimicrobial effect of polyphenols from apple skins on human bacterial pathogens
Provedor de dados: Electronic Journal of Biotechnology
Autores: Alberto,María Rosa; Rinsdahl Canavosio,Matías Andrés; Manca de Nadra,María Cristina.
Apples possess many beneficial properties for the human health related with their high content in phenolic compounds. The antimicrobial effect of these compounds from the skin of two apple varieties, Royal Gala and Granny Smith, against human pathogens was examined. The phenolic compounds were extracted with the following solvents: A, acetone: water: acetic acid; B, ethyl acetate: methanol: water and C, ethanol: water. Total phenolic, flavonoid and non-flavonoid contents were analyzed in the extracts. The antimicrobial effect was determined using the agar diffusion method. The highest inhibitory effect of both apple varieties corresponded to extract A, which contained a high phenolic content. The Granny Smith extracts with higher phenolic content presented...
Tipo: Journal article
Palavras-chave: Bacterial inhibition; Granny Smith; Royal Gala; Pathogens; Phenolic extracts.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300006

Therapeutic angiogenesis following intramuscular gene transfer of vascular endothelialgrowth factor 121 in a dog model of hindlimb ischemia
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ojalvo,Ariana G.; Seralena,Alina; Vázquez,Raysa; Montequín,José F; Vispo,Nelson S.; Silva,Ricardo; Aldama,Alfredo; Puchades,Yaquelin; Sorell,Luis T.; Lopez-Saura,Pedro; Alfonso,María A.; Simón,Rafael; Alí,Alfonso; Seuc,Armando; Herrera,Luis.
Abstract &lt;A HREF="../../../../fbpe/img/ejb/v6n3/a02/bip/bip.html"&gt;Reprint (BIP)&lt;/A&gt; &lt;A HREF="../../../../fbpe/img/ejb/v6n3/a02/reprint.html"&gt;Reprint (PDF)&lt;/A&gt; Abstract &lt;A HREF="#article"&gt;Article &lt;/A&gt; &lt;A HREF="#references"&gt;References &lt;/A&gt; Vascular endothelial growth factor (VEGF), an endothelial cell-specific mitogen, has been shown to promote therapeutic angiogenesis in animal models of critical limb ischemia. Ischemic skeletal muscle is advantageous for taking up and expressing foreign genes transferred as naked plasmid DNA. Accordingly, we investigated the hypothesis that intramuscular administration of naked plasmid DNA encoding the 121-amino acid isoform of VEGF could augment collateral development and...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300006

GMOs and Development
Provedor de dados: Electronic Journal of Biotechnology
Autores: DaSilva,Edgar J.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200001

Enhancing DNA electrotransformation efficiency in Escherichia coli DH10B electrocompetent cells
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wu,Ning; Matand,Kanyand; Kebede,Bizuayehu; Acquaah,George; Williams,Sonya.
Electrotransformation also known as electroporation is the most reliable and efficient tool for plasmid DNA uptake. Electrotransformation efficiency is function of many factors which include (1) number of cell washes prior to electroporation, (2) electroporation cell number, (3) electroporation DNA amount, and (4) cell growth phase. Those factors have limitedly been concomitantly investigated in E. coli DH10B strain. This study is aimed to explore above key factors to define the optimal conditions for high electrotransformation efficiency. The results showed that electrotransformation efficiency of E. coli DH10B was enhanced to 1.5 x 10(9) cfu/µg by washing cells three times with 15 ml of 10% glycerol. This washed off extra salts from cell suspension and...
Tipo: Journal article
Palavras-chave: Cell competency; DNA; E. coli DH10B; Electroporation.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500021

Genetic diversity of Brassica oleracea var. capitata gene bank accessions assessed by AFLP
Provedor de dados: Electronic Journal of Biotechnology
Autores: Faltusová,Zuzana; Kuera,Ladislav; Ovesná,Jaroslava.
The genetic diversity of 20 cabbage (Brassica oleracea var. capitata, including sub.var. alba and rubra) cultivars and landraces from the Gene bank of Crop Research Institute was estimated using amplified fragment length polymorphism (AFLP) marker technology. Two cultivars of Brassica pekinensis (syn. Brassica rapa var. pekinensis) were used as outliers in the study. Thirty AFLP primer combinations produced a total of 1084 fragments. A total of 806 fragments, 364 (45%) of them polymorphic, were found across 20 Brassica oleracea var. capitata accessions. The accessions were clustered into two main groups. Special subgroups, reflecting place of origin, were observed within these groups. Ten selective primer pairs were found to be most informative because...
Tipo: Journal article
Palavras-chave: Amplified fragment length polymorphism; Brassica oleracea var. capitata; Cabbage; Discriminatory power; Genetic diversity.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300011

Diet high in &amp;#945;-linolenic acid up-regulate PPAR-&amp;#945; gene expression in the liver of goats
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ebrahimi,Mahdi; Rajion,Mohamed Ali; Meng,Goh Yong; Farjam,Abdoreza Soleimani; Oskoueian,Ehsan; Jafari,Saeid.
Background There is little information on the effects of diets containing high &amp;#945;-linolenic acid (C18:3n-3) on liver lipid composition and lipogenic gene expressions. In this study fourteen goats (Capra aegagrus hircus) were fed either a flaxseed oil (FSO) supplemented diet containing high &amp;#945;-linolenic acid or a control diet without added flaxseed oil (CON) for 100-d to evaluate the effects on liver lipid composition and the gene expression of peroxisome proliferator-activated receptors (PPAR-&amp;#945;) and stearoyl-CoA-desaturase (SCD) in the liver. Results An increase in the levels of C18:3n-3 and C20:5n-3, C22:5n-3, C22:6n-3 was observed in the liver of FSO-treated goats. There was a significant (P &lt; 0.05) up-regulation of...
Tipo: Journal article
Palavras-chave: Gene expression; Goat; Liver; Omega-3 fatty acid; PPAR.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300011

Development of cDNA-derived SSR markers and their efficiency in diversity assessment of Cymbidium accessions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Moe,Kyaw Thu; Hong,Woo-Ju; Kwon,Soon-Wook; Park,Yong-Jin.
Cymbidium spp. are popular &amp;#64258;owering plants. Assessment of the genetic diversity in cultivated Cymbidium facilitates conservation of germplasm and subsequent cultivar improvement. Thus, it is important to develop more efficient polymorphic DNA markers. Although more motifs (403) were identified and more primers (206) were designed in the genomic library compared to the cDNA library, a larger number of successful primers were obtained from the cDNA library (59.9%) than from genomic DNA library (51.1%). However, higher PIC and gene diversity were identified in genomic SSRs. The average allele number per locus was also higher in genomic SSRs (7.3) than EST-SSRs (5.2), among the 24 evaluated Cymbidium accessions. AT/TA was comparatively high in...
Tipo: Journal article
Palavras-chave: CDNA library; Cymbidium; Enriched library; Molecular diversity; SSR.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000200004

Influence of novel lignocellulosic residues in a biobed biopurification system on the degradation of pesticides applied in repeatedly high doses
Provedor de dados: Electronic Journal of Biotechnology
Autores: Diez,M. Cristina; Tortella,Gonzalo R; Briceño,Gabriela; Castillo,Maria del Pilar; Díaz,Jorge; Palma,Graciela; Altamirano,Carolina; Calderón,Carolina; Rubilar,Olga.
Background: The biobed is a simple biopurification system used to prevent the point-source pesticide contamination that occurs at farm level. The typical composition of the biomixture used in this system is soil, peat and straw in volumetric proportions of 1:1:2. The principal component is straw due to its positive effects on biological activity and thus pesticide degradation. However, access to straw can be limited in some regions, so it must be replaced by other more readily available lignocellulosic residues. Results: Therefore, two alternate lignocellulosic materials (barley husks and pine sawdust) were evaluated as partial substitutes for straw. The degradation of a repeatedly applied mixture of six pesticides by these alternates was assessed. The...
Tipo: Journal article
Palavras-chave: Biopurification system; Biomixture; Lignocellulosic materials; Pesticide degradation.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600011

Feasible biotechnological and bioremediation strategies for serpentine soils and mine spoils
Provedor de dados: Electronic Journal of Biotechnology
Reclamation of metalliferous areas is a priority field of biogeochemistry of trace elements. Ultramafic outcrops rich in heavy metals have been mapped in different parts of the world. Heavy metals are potentially cytotoxic, caricinogenic and mutagenic. Environment protection agencies and legislations insisting the mine operators to restore the mine spoils and tailings since the metal leachates have serious implications in production of healthy agricultural products. Hence, restoration of mine spoils, tailings and metalliferous soils is a challenging task for the well being of Humans. Synthetic and natural zeolites have been used as chelators for rapid mobility and uptake of metals from contaminated soils by plants. Use of synthetic chelators significantly...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000100003

Biosorption of lead(II) and chromium(VI) on groundnut hull: Equilibrium, kinetics and thermodynamics study
Provedor de dados: Electronic Journal of Biotechnology
Autores: Qaiser,Suleman; Saleemi,Anwar R; Umar,Muhammad.
The biosorption of lead(II) and chromium(VI) on groundnut hull was investigated. Batch biosorption experiments were conducted to find the equilibrium time and biosorption capacity. Effect of parameters like pH, temperature and initial metal concentration was studied. The maximum biosorption capacity of lead(II) and chromium(VI) was found to be 31.54 ± 0.63 and 30.21 ± 0.74 mg g-1, respectively. The optimum pH for lead(II) and chromium(VI) removal was 5 ± 0.1 and 2 ± 0.1, respectively. The temperature change, in the range of 20 - 45ºC affected the biosorption capacity. The maximum removal of lead(II) was achieved at 20 ± 2ºC, where as maximum uptake of chromium(VI) was observed at 40 ± 2ºC. The biosorption data was fitted to the Langmuir and the Freundlich...
Tipo: Journal article
Palavras-chave: Biosorption; Equilibrium; Groundnut hull; Kinetics; Thermodynamics.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400003

The applicability of the API 20E and API Rapid NFT systems for the identification of bacteria from activated sludge
Provedor de dados: Electronic Journal of Biotechnology
Autores: Juang,Der-Fong; Morgan,Joe M.
The purpose of this study was to test the applicability of the API 20E and API Rapid NFT systems for the identification of some predominant gram-negative and gram-positive bacteria isolated from lab-scale activated sludge treatment systems. In this study, one lab-scale sequencing batch reactor (SBR) and one lab-scale continuous-flow stirred tank reactor (CFSTR) were setup. After both reactors had reached equilibrium, many pure cultures isolated from the activated sludge in both systems were obtained and many morphological, biochemical, physiological tests were conducted to identify each pure culture. The API 20E system is a standardized, miniaturized version of conventional procedures for rapid identification of Enterobacteriaceae and other gram-negative...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000100002

Studies on the effect of pH on the sorption of Pb2+ and Cd2+ ions from aqueous solutions by Caladium bicolor (Wild Cocoyam) biomass
Provedor de dados: Electronic Journal of Biotechnology
Autores: Horsfall Jnr,Michael; Spiff,Ayebaemi I.
Environmental protection requires the use of natural products instead of chemicals to minimize pollution. This investigation studies the use of a non-useful plant material as naturally occurring biosorbents for the removal of cationic pollutants in wastewater. The effect of pH on the sorption of Pb2+ and Cd2+ ion onto Caladium bicolor corm biomass was investigated. The experimental results have been analysed in terms of Langmuir, Freundlich and Flory-Huggins isotherms. The data showed that the maximum pH (pHmax) for efficient sorption of Pb2+ was 7.0 and for Cd2+ 5.0. Evaluation using Langmuir equation gave the monolayer sorption capacity as 88.50 mg/g and 65.50 mg/g at the respective pHmax for Pb2+ and Cd2+. Surface characterization of acid and base...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300014

Biotransformation of 3-hydroxydibenzo-&amp;#945;-pyrone into 3,8 dihydroxydibenzo-&amp;#945;-pyrone and aminoacyl conjugates by Aspergillus niger isolated from native&amp;#8220;shilajit&amp;#8221;
Provedor de dados: Electronic Journal of Biotechnology
Autores: Islam,Aminul; Ghosh,Runa; Banerjee,Dipankar; Nath,Piali; Mazumder,Upal Kanti; Ghosal,Shibnath.
&amp;#8220;Shilajit&amp;#8221; is a panacea in Ayurveda, the Indian traditional system of medicine. The major bioactives of &amp;#8220;shilajit&amp;#8221; have been identified as dibenzo-&amp;#945;-pyrones (DBPs), its oligomers and aminoacyl conjugated derivatives. These bioactive compounds play a crucial role in energy metabolism in all animal cells including those of man. 3-hydroxydibenzo-&amp;#945;-pyrone (3-OH-DBP), a key DBP component of &amp;#8220;shilajit&amp;#8221; is converted, among other products, to another active DBP derivative, viz. 3,8-hydroxydibenzo-&amp;#945;-pyrone, 3,8(OH)2-DBP, in vivo, when its precursor is ingested. 3,8(OH)2-DBP is then involved in energy synthesis in the mitochondria in the reduction and stabilization of coenzyme Q10...
Tipo: Journal article
Palavras-chave: Coenzyme Q10 reduction; Electron transport chain humification; Paleohumus.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300001

Establishment of an in vitro micropropagation protocol for Mecardonia tenella
Provedor de dados: Electronic Journal of Biotechnology
Autores: Alderete,Liliana Marisol; Mori,Marcela; Kato,Adriana; Salvio Escandón,Alejandro.
Mecardonia tenella is an attractive herbaceous native plant, characterized by their intense green foliage and their abundant yellow flowers. It is a very interesting plant for pot and/or garden. A trait to improve in this species is the size of the flowers. The goal of the present paper is to study the in vitro behaviour of M. tenella and to establish a routine protocol for its micropropagation. For the in vitro establishment of M. tenella, nodal segments were disinfected by standard methods using ethanol/sodium hypochloride and cultured on hormone-free MS medium, supplemented with a mixture of antibiotics and an antifungal. In order to study the hormonal requirements of the species, nodal segments were cultured on basal MS supplemented with...
Tipo: Journal article
Palavras-chave: In vitro; Micropropagation; Scrophulariaceae.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300017

Enhance 1,3-propanediol production from crude glycerol in batch and fed-batch fermentation with two-phase pH-controlled strategy
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sattayasamitsathit,Supalak; Methacanon,Pawadee; Prasertsan,Poonsuk.
The batch fermentation of 1,3-propanediol (1,3-PD) by Klebsiella pneumoniae SU6 at different crude glycerol concentration (40-100 g l-1), pH (6.5-7.5) and temperature (31-40ºC) combined with two-phase pH-controlled strategy was investigated. Effect of feeding rate (0.10-0.15 L h-1) was studied in fed-batch fermentation. In batch fermentation, the optimal condition was 60 g l-1 crude glycerol, pH control at 6.5 and cultivation temperature at 37ºC. The maximum 1,3-PD of 20 g l-1, the yield of 0.34 g 1,3-PD g-1 glycerol consumed and the productivity of 1.25 g l-1 h-1 were achieved at 16 hrs cultivation. The by-products were acetic acid and succinic acid at 2.7 and 1.1 g l-1, respectively. Two-phase pH-controlled strategy gave better results (24.95 g l-1...
Tipo: Journal article
Palavras-chave: 1; 3-propanediol crude glycerol fed-batch fermentation Klebsiella pneumonia two-phase pH-control.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600004

Novel antimicrobial secondary metabolites from a Penicillium sp. isolated from Brazilian cerrado soil
Provedor de dados: Electronic Journal of Biotechnology
Autores: Petit,Philippe; Lucas,Esther M. F.; Abreu,Lucas M; Pfenning,Ludwig H; Takahashi,Jacqueline A.
The morphological features of a Penicillium, isolated from Brazilian cerrado soil, were characterized and showed to be distinctly different from all well-defined Penicillium species. Chemical and biological investigation on the ethyl acetate extract of this Penicillium isolate resulted in the isolation of three new naphthalenoids: a major metabolite, methyl 6-acetyl-4-methoxy-5,7,8-trihydroxynaphthalene-2-carboxylate and two minor ones, methyl 6-acetyl-4-methoxy-7,8-dihydroxynaphthalene-2-carboxylate and methyl 6-acetyl-4-methoxy-5,8-dihydroxynaphthalene-2-carboxylate. Their structures were determined based on their mono and bidimensional nuclear magnetic resonance data. Acetyl, allyl and methoxyl derivatives of the major metabolite were prepared in order...
Tipo: Journal article
Palavras-chave: Antibacterial activity; Cerrado; Naphthalenoids; Penicillium; Secondary metabolites.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400008

Cloning of the &amp;#969;-secalin gene family in a wheat 1BL/1RS translocation line using BAC clone sequencing
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Meng Jun; Li,Ya Qing; Zhang,Nan; Shi,Zhan Liang.
Background: Wheat 1BL/1RS translocation lines are planted around the world for their disease resistance and high yield. Most of them are poor in bread making, which is partially caused by &amp;#969;-secalins that are encoded by the &amp;#969;-secalin gene family, which is located on the short arm of rye chromosome 1R (1RS). However, information on the structure and evolution of the &amp;#969;-secalin gene family is still limited. Results: We first generated a physical map of the &amp;#969;-secalin gene family covering 195 kb of the Sec-1 locus based on sequencing three bacterial artificial chromosome (BAC) clones of the 1BL/1RS translocation wheat cultivar Shimai 15. A BAC contig was constructed spanning 168 kb of the Sec-1 locus on 1RS. Twelve...
Tipo: Journal article
Palavras-chave: Bacterial artificial chromosome (BAC) Wheat &amp;#969; -Secalin 1BL/1RS translocation line.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300010

Methyl jasmonate induced overproduction of eleutherosides in somatic embryos of Eleutherococcus senticosus cultured in bioreactors
Provedor de dados: Electronic Journal of Biotechnology
Autores: Shohael,Abdullah Mohammad; Murthy,Hosakatte Niranjana; Hahn,Eun-Joo; Paek,Kee-Yoeup.
This study was concentrated on the production of eleutherosides and chlorogenic acid in embryogenic suspension cultures of Eleutherococcus senticosus by exposing them to different concentrations (50-400 µM) of methyl jasmonate (MJ) during the culture period. In the bioreactor cultures, eleutheroside content increased significantly by elicitation of MJ, however, the fresh weight, dry weight and growth ratio of embryos was strongly inhibited by increasing MJ concentrations. The highest total eleutheroside (7.3 fold increment) and chlorogenic acid (3.9 fold increment) yield was obtained with 200 µM MJ treatment. There was 1.4, 3.4 and 14.9 fold increase in the eleutheroside B, E, and E1 production respectively with such elicitation treatment. These results...
Tipo: Journal article
Palavras-chave: Eleutherosides; Elicitation; Methyl jasmonate; Secondary metabolite; Siberian ginseng; Suspension culture.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400016

Extent and structure of genetic diversity in a collection of the tropical multipurpose shrub legume Cratylia argentea (Desv.) O. Kuntze as revealed by RAPD markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Andersson,Meike S; Schultze-Kraft,Rainer; Peters,Michael; Duque,Myriam C; Gallego,Gerardo.
The tropical multipurpose shrub legume Cratylia argentea is well adapted to acid soils of low to medium fertility and has excellent drought-tolerance. Due to its high nutritive value it is particularly suited as forage for dry-season supplementation. A collection of 47 C. argentea accessions in a collection, derived from seed replicating of original accessions with differing geographic origin and morphological and agronomic characteristics was investigated using molecular markers (RAPD (random amplified polymorphic DNA)). Genetic diversity (H T = 0.145) in the collection was low, with 30% of differentiation among groups and high genetic similarity among accessions (GS = 0.805). Within-accession variability was high. One taxonomic mismatch and five possible...
Tipo: Journal article
Palavras-chave: Agroforestry; Molecular markers; MPT (multipurpose shrubs and trees); Tropics.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300006

Modelling of the biofiltration of reduced sulphur compounds through biotrickling filters connected in series: Effect of H2S
Provedor de dados: Electronic Journal of Biotechnology
Autores: Silva,Javier; Morales,Marjorie; Cáceres,Manuel; Morales,Paulina; Aroca,Germán.
Background: The behaviour of two biotrickling filters connected in serie (BTF) inoculated with Acidithiobacillus thiooxidans and Thiobacillus thioparus, biodegrading hydrogen sulphide (H2S) and dimethyl sulphide (DMS) simultaneously were studied. A model which considers gas to liquid mass transfer and biooxidation in the biofilm attached to the support is developed. Additionally, a fixed bed biotrickling filter where the microorganism is immobilized in a biofilm which degrades a mixture of H2S and DMS is implemented. Validation of the model was carried out using experimental data obtained at different H2S and DMS loads. Results: The inhibitory effect caused by the presence of H2S on the DMS is observed, which is evidenced by the decrease of the DMS removal...
Tipo: Journal article
Palavras-chave: Biofiltration; DMS; Hydrogen sulphide; Mathematical model; Thiobacillus thioparus.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000300007

Biocontrol capacity of wild and mutant Trichoderma harzianum (Rifai) strains on Rhizoctonia solani 618: effect of temperature and soil type during storage
Provedor de dados: Electronic Journal of Biotechnology
Autores: Montealegre,Jaime; Valderrama,Luis; Herrera,Rodrigo; Besoaín,Ximena; Pérez,Luz M.
Wild (Th11, Th12 and Th650) and mutant (Th11A80.1, Th12A40.1, Th12C40.1 and Th650-NG7) Trichoderma harzianum strains were stored for 180 days at 5ºC or at 22ºC, in two types of soils. Strains recovered at 90, 120 and 180 days from the two types of soils, retained their full capacity to biocontrol Rhizoctonia solani 618, that produces crown and root rot of tomatoes. Recovery, estimated as colony forming units (cfu) of the wild and mutant strains, showed that all increased their cfu after storage independently of the type of soil and temperature, although kinetic behavior differed among strains. Ratios of recovery after storage in type B soil/ type A soil or at 22ºC/5ºC, higher or lower than one respectively, allowed to establish that Th11 and Th12 were the...
Tipo: Journal article
Palavras-chave: Bioantagonism; Persistence; Root rot; Tomato.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400002

Development, characterization and use of genomic SSR markers for assessment of genetic diversity in some Saudi date palm (Phoenix dactylifera L.) cultivars
Provedor de dados: Electronic Journal of Biotechnology
Autores: Al-Faifi,Sulieman A; Migdadi,Hussein M; Algamdi,Salem S; Altaf Khan,Mohammad; Ammar,Megahed H; Al-Obeed,Rashid S; I. Al-Thamra,Mohammad; EL-Harty,Ehab H; Jakse,Jerenj.
Background: The present study was undertaken towards the development of SSR markers and assessing genetic relationships among 32 date palm (Phoenix dactylifera L.) representing common cultivars grown in different geographical regions in Saudi Arabia. Results: Ninety-three novel simple sequence repeat markers were developed and screened for their ability to detect polymorphism in date palm. Around 71% of genomic SSRs were dinucleotide, 25% tri, 3% tetra and 1% penta nucleotide motives. Twenty-two primers generated a total of 91 alleles with a mean of 4.14 alleles per locus and 100% polymorphism percentage. A 0.595 average polymorphic information content and 0.662 primer discrimination power values were recorded. The expected and observed heterozygosities...
Tipo: Journal article
Palavras-chave: Expected and observed heterozygosity; Microsatellite markers; Polymorphic information content; Polymorphism; Primer discrimination power.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300002

Global health care challenge: Indian experiences and new prescriptions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wakdikar,Sandhya.
Globally, there has been an unparalleled growth in the plant-derived medicinally useful formulations, drugs and health-care products, its market covering more than 60% products derived from plant origin. India exhibits remarkable outlook in modern medicines that are based on natural products besides traditional system of Indian medicines. Almost, 70% modern medicines in India are derived from natural products. Medicinal plants play a central role not only as traditional medicines but also as trade commodities, meeting the demand of distant markets. Ironically, India has a very small share (1.6%) of this ever-growing global market. To compete with the growing market, there is urgency to expeditiously utilize and scientifically validate more medicinally...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300002

Removal of heavy metal from industrial wastewater using chitosan coated oil palm shell charcoal
Provedor de dados: Electronic Journal of Biotechnology
Autores: Saifuddin M,Nomanbhay; Kumaran,Palanisamy.
This research focuses on understanding biosorption process and developing a cost effective technology for treatment of heavy metals-contaminated industrial wastewater. A new composite biosorbent has been prepared by coating chitosan onto acid treated oil palm shell charcoal (AOPSC). Chitosan loading on the AOPSC support is about 21% by weight. The shape of the adsorbent is nearly spherical with particle diameter ranging 100~150 &amp;micro;m. The adsorption capacity of the composite biosorbent was evaluated by measuring the extent of adsorption of chromium metal ions from water under equilibrium conditions at 25&amp;ordm;C. Using Langmuir isotherm model, the equilibrium data yielded the following ultimate capacity values for the coated biosorbent on a per...
Tipo: Journal article
Palavras-chave: Chitosan bioabsorbent; Chromium (III); Chromium (IV); Heavy metal adsorption; Oil palm shell charcoal.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100008

Effect of vermicompost, worm-bed leachate and arbuscular mycorrizal fungi on lemongrass (Cymbopogon citratus (DC) Stapf.) growth and composition of its essential oil
Provedor de dados: Electronic Journal of Biotechnology
Autores: León-Anzueto,Elizabeth; Abud-Archila,Miguel; Dendooven,Luc; Ventura-Canseco,Lucía María Cristina; Gutiérrez-Miceli,Federico A.
The objective of this study was to investigate the effect of vermicompost, worm-bed leachate (WBL) and Glomus mosseae, an arbuscular mycorrhizal fungi (AMF), on growth of lemongrass (Cymbopogon citratus (DC.) Stapf). A response surface methodology, i.e. a three-level Box Benhen design with three repetitions and three blocks, was applied to optimize biomass production, essential oil yield and its composition. Application rates of Glomus mosseae were 0, 1 or 2 g plant-1, vermicompost 0, 5 or 10 g plant-1 and WBL 0, 10 and 20%. The AMF had no significant effect on the variables tested, but vermicompost had a significant effect on essential oil yield and WBL on essential oil yield, myercene concentration and shoot dry weigh (p &lt; 0.05). It was found that...
Tipo: Journal article
Palavras-chave: Citral; Desirability function; Lemongrass; Myrcene; Optimization; Response surface methodology.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600005

Effects of elicitor and copper sulfate on grindelic acid production in submerged cultures of Grindelia pulchella
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hernandez,Xenia E; Orden,Alejandro A; Giordano,Oscar S; Kurina,Marcela.
Grindelia pulchella callus and cell suspension cultures were established from seedling leaves. When several phytoregulator supplementations were assayed in solid Murashige and Skoog medium containing 3% (w/v) of sucrose (MS medium), combinations of indole-3-butyric acid (IBA) and N6-benzylaminopurine (BA) resulted the most appropriate conditions to generate fast growing friable calli with detectable levels of grindelic acid. Moreover, the same basal media supplemented with 20.0 µM IBA/4.4 µM BA was found to be optimal for cell growth in submerged cultures (µmax = 0.26 days-1) while the addition of 20.0 µM IBA/18.0 µM BA resulted in a relative higher metabolite production (4.55 mg/gDW) when the inocula was 5% (v/v). Furthermore, three different stress...
Tipo: Journal article
Palavras-chave: Cu2+; Dimethylsulfoxide permeabilization; Grindelane diterpenes; Jasmonic acid.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300007

A laboratory scale device for microencapsulation of genetically engineered cells into alginate beads
Provedor de dados: Electronic Journal of Biotechnology
Autores: León Fiszman,Gabriel; Karara,Armando Luis; Finocchiaro,Liliana María Elena; Glikin,Gerardo Claudio.
The microencapsulation of recombinant cells, widely used for in vitro high-density cell culture, is a novel and potentially cost-effective method of in vivo heterologous protein delivery, where the protein producing cells are immunologically protected from tissue rejection. We report here a simple, reliable and inexpensive laboratory method to generate calcium alginate microcapsules containing genetically engineered, interleukin-2 expressing, Chinese hamster ovary (CHO) cells.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300012

Cassava and the future of starch
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tonukari,Nyerhovwo John.
The nutritive reserves of cassava is made up of starch, which is one of the most important products synthesized by plants that is consumed as food and used in industrial processes. The currently increasing cassava production will lead to higher amount of starch available making it cheaper for industrial processes, and opening up new markets. There is also abundant capacity in many tropical countries such as Nigeria to increase cassava production.
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000100003

Optimization of b-galactosidase production using Kluyveromyces lactis NRRL Y-8279 by response surface methodology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Dagbagli,Seval; Goksungur,Yekta.
This paper investigates the production and optimization of b-galactosidase enzyme using synthetic medium by Kluyveromyces lactis NRRL Y-8279 in shake flask cultures. Among the different cell disintegration methods used, the highest specific activity was obtained when the cells were permeabilized using isoamyl alcohol. Response surface methodology was used to investigate the effects of four fermentation parameters (agitation speed, pH, initial substrate concentration and incubation time) on b-galactosidase enzyme production. Results of the statistical analysis showed that the fit of the model was good in all cases. Maximum specific enzyme activity of 4218.4 U g-1 was obtained at the optimum levels of process variables (pH 7.35, agitation speed 179.2 rpm,...
Tipo: Journal article
Palavras-chave: B-galactosidase; Kluyveromyces lactis; Response surface methodology; Shake flask culture; Synthetic medium.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400011

Nutrient optimization for production of polyhydroxybutyrate from halotolerant photosynthetic bacteria cultivated under aerobic-dark condition
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sangkharak,Kanokphorn; Prasertsan,Poonsuk.
Three halotolerant bacterial strains; Rhodobacter sphaeroides ES16 (the wild type) and the two mutant strains of R. sphaeroides ES16, namely N20 and U7, were cultivated in glutamate-malate (GM) medium and screened for production of polyhydroxybutyrate (PHB). The mutant strains N20 and U7 were found to accumulate PHB (53.9 and 42.0% of DCW, respectively) 3.6 and 2.8 times higher than the wild type strain (19.5% of DCW), respectively. R. sphaeroides N20 were selected for studies on the effects of nutrient and environmental conditions on PHB accumulation. The optimal condition was 4 g/l acetate, 0.02 g/l (NH4)2SO4, C/N ratio of 6:1, 1.0 g/l K2HPO4, 1.0 g/l KH2PO4 and 3% NaCl with initial pH at 7.0. Under this optimal condition, the maximum PHB accumulation...
Tipo: Journal article
Palavras-chave: Aerobic-dark cultivation; Optimization; PHB; Polyhydroxybutyrate; Rhodobacter sphaeroides.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300009

Efficient Agrobacterium tumefaciens-mediated transformation of Malus zumi (Matsumura) Rehd using leaf explant regeneration system
Provedor de dados: Electronic Journal of Biotechnology
Autores: Xu,Jin; Wang,Yu Zhen; Xia Yin,Heng; Jing Liu,Xiao.
Malus zumi is known as an excellent dwarfing apple rootstock occurring in natural or arid/semiarid soil or salina. Gene manipulation of M. zumi through transgenic technology can modify plant feature for further improvement fruit tree production by grafting the scion on a transgenic rootstock. Here, we report the establishment of an efficient, in vitro, shoot regeneration system and Agrobacterium tumefaciens- mediated transformation from the leaf explants for Malus zumi (Matsumura) Rehd. Leaf explants were infected with Agrobacterium strains containing nptII and gus gene. The highest frequency of shoot regeneration was obtained on MS medium containing 500 mg l-1 Lactalbumin hydrolysate, 30 g l-1 fructose, supplemented with 3.0 mg l-1 BA, 0.2 mg l-1...
Tipo: Journal article
Palavras-chave: Agrobacterium tumefaciens; Apple rootstock; Genetic transformation.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000100003

Isolation of purple nonsulfur bacteria for the removal of heavy metals and sodium from contaminated shrimp ponds
Provedor de dados: Electronic Journal of Biotechnology
Autores: Panwichian,Saijai; Kantachote,Duangporn; Wittayaweerasak,Banjong; Mallavarapu,Megharaj.
In order to determine whether waters used for the shrimp cultivation contained toxic levels of heavy metals (HMs) and sodium (Na), analysis was carried out on 31 shrimp ponds in areas of southern Thailand. Purple nonsulfur bacteria (PNB) were also isolated from the same ponds to investigate if they could be used for bioremediation of the above contaminants. The highest HMs concentrations of the sediment samples in mg/kg dry weight were found as follows: 0.75 cadmium (Cd), 62.63 lead (Pb), 34.60 copper (Cu) and 58.50 zinc (Zn). However, all sediment samples met Hong Kong standards for dredged sediment. In contrast, contamination of Cu (9-30 µg/L) and Zn (140-530 µg/L) exceeding the standard guidelines for marine aquatic animal set by the Pollution Control...
Tipo: Journal article
Palavras-chave: Bioremediation; Heavy metals; Purple nonsulfur bacteria; Salinity; Shrimp farming.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400003

Molecular cloning and expression analysis of the MaASR1 gene in banana and functional characterization under salt stress
Provedor de dados: Electronic Journal of Biotechnology
Autores: Miao,Hongxia; Wang,Yuan; Liu,Juhua; Jia,Caihong; Hu,Wei; Sun,Peiguang; Jin,Zhiqiang; Xu,Biyu.
Background Abscisic acid (ABA)-, stress- and ripening-induced protein (ASR) is plant-specific hydrophilic transcriptional regulators involved in sucrose stress and wounding in banana. However, it is not known whether banana ASR genes confer salt stress tolerance. The contexts of the study was to analysis the sequence characterization of banana ASR1, and identify its expression patterns and function under salt stress using quantitative real-time PCR (qPCR) and overexpression in Arabidopsis. The purpose was to evaluate the role of banana ASR1 to salt stress tolerance employed by plants. Results A full-length cDNA isolated from banana fruit was named MaASR1, and it had a 432 bp open reading frame (ORF) encoding 143 amino acids. MaASR1 was preferential...
Tipo: Journal article
Palavras-chave: ASR; Banana; Expression patterns; Salt resistance.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600006

Isolation of adh mutant of Lactobacillus rhamnosus for production of L(+) Lactic acid
Provedor de dados: Electronic Journal of Biotechnology
Autores: Narayanan,Niju; Roychoudhury,Pradip K.; Srivastava,Aradhana.
Lactobacillus rhamnosus, a facultative anaerobe, which produces L (+) lactic acid and ethanol under anaerobic conditions, is used in the present study. An adh- mutant of Lactobacillus rhamnosus MTCC 1408, was developed by chemical mutagenesis, which could produce pure L(+) lactic acid as the only product. Batch fermentation kinetics of the wild type and the mutant strain were studied in glucose-yeast extract medium under conditions of temperature 40ºC and pH 6.2 anaerobically. The biomass yield was similar in both wild type and mutant strains, however lactic acid yield increased by 6.6%. A chemically defined media was optimized for supplementation of succinate, acetate and citrate for better biomass formation using single variable optimisation. It was...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000100010

Choice of the adequate quantification method for recombinant human GM-CSF produced in different host systems
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bollati Fogolín,Mariela; Eberhardt,Marcos Oggero; Kratje,Ricardo; Etcheverrigaray,Marina.
Three enzyme-linked-immunosorbent assays (ELISA) were developed and compared with a bioassay to quantify the recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF). These assays were suitable to quantify the non-glycosylated rhGM-CSF present in mixtures with variable protein content, and therefore useful for determining concentrations of the cytokine in production processes. Among these assays, the competitive ELISA, developed with a MAb that recognises an epitope not involved in glycosylation, was the only one suitable to quantify the glycosylated form of rhGM-CSF produced in mammalian cell cultures.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300008

Bioaugmentation of latex rubber sheet wastewater treatment with stimulated indigenous purple nonsulfur bacteria by fermented pineapple extract
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kornochalert,Nastee; Kantachote,Duangporn; Chaiprapat,Sumate; Techkarnjanaruk,Somkiet.
Background Treating latex rubber sheet wastewater often leads to the generation of a rotten-egg odor from toxic H2S. To increase the treatment efficiency and eliminate H2S, purple nonsulfur bacteria (PNSB), prepared by supplementing non-sterile rubber sheet wastewater (RAW) with fermented pineapple extract (FPE), were used to treat this wastewater under microaerobic light conditions. The following 3 independent variables: chemical oxygen demand (COD), initial pH and FPE dose were investigated using the Box-Behnken design to find optimal conditions for stimulating the growth of indigenous PNSB (PNSBsi). Results The addition of 2.0% FPE into RAW, which had a COD of 2000 mg L- 1 and an initial pH of 7.0, significantly decreased oxidation reduction potential...
Tipo: Journal article
Palavras-chave: Bioremediation; Fermented plant extract; Response surface methodology; Rotten-egg odor; Rubber wastewater.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000400006

Batch culture growth of Chlorella zofingiensis on effluent derived from two-stage anaerobic digestion of two-phase olive mill solid waste
Provedor de dados: Electronic Journal of Biotechnology
Autores: Travieso Córdoba,Lissette; Domínguez Bocanegra,Alma Rosa; Rincón Llorente,Bárbara; Sánchez Hernández,Enrique; Benítez Echegoyen,Francisco; Borja,Rafael; Raposo Bejines,Francisco; Colmenarejo Morcillo,Manuel Francisco.
This paper presents the use of an effluent derived from two-stage anaerobic digestion of two-phase olive mill solid waste (OMSW) as a substrate for the production of Chlorella zofingiensis in batch mode. Chlorella zofingiensis when grown autotrophycally can accumulate significant quantities of valuable carotenoids which are used as an additive in fish and poultry farming, as colorants in foods and in health care products. It was found that two-phase OMSW previously treated by two-stage anaerobic digestion and further sterilized may be used as a culture medium for the microalgae Chlorella zofingiensis. Typical growth curves were obtained using both the above-mentioned anaerobic effluent and a synthetic medium. Total chemical oxygen demand (TCOD) and soluble...
Tipo: Journal article
Palavras-chave: Batch culture; Chlorella zofingiensis; Kinetic parameters; Substrate; Two-phase olive mill solid waste; Two-stage anaerobic digestion.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200003

Biotechnological processes for chitin recovery out of crustacean waste: A mini-review
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gortari,María Cecilia; Hours,Roque Alberto.
Background: Chitin is an important natural resource. The annual worldwide production is estimated in approximately 10(10)-10(12) ton. It is produced by arthropods (insects and crustaceans), molluscs and fungi. Its main biological function is structural. Crustacean shells are the most important chitin source for commercial use due to its high content and ready availability. Chitin and its derivatives have great economical value because of their numerous applications: food, cosmetics, pharmaceuticals, textile industries, waste water treatment and agriculture. In nature, chitin is closely associated with proteins, minerals, lipid and pigments, which have to be removed. Results: Several techniques to extract chitin from different sources have been reported....
Tipo: Journal article
Palavras-chave: Biological extraction; Chitin production; Crustacean waste.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300014

Plant virus gene expression strategies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bustamante,Pedro I.; Hull,Roger.
Plant viruses can cause serious losses to most, if not all, major crops upon which depend for food. Many viruses are endemic, causing moderate losses each year. Others, such as those causing rice tungro, give periodic severe epidemics. There are no fully collated figures for world-wide losses due to viruses but some examples has been listed, i.e., rice tungro in SE ASIA and african cassava mosaic in Africa with 1,500 and 2,000 millions dollars per year in losses respectively. However, in recent years the understanding of the genome organisation of plant viruses has increased in parallel with development of molecular biological techniques. The ability to obtain nucleotide sequences of complete viral genomes has also permitted the elucidation and...
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000200003

Identification and expression analysis of two Wnt4 genes in the spotted scat (Scatophagus argus)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chen,Jianhua; Yinglei,Li; Zhang,Junbin; Liu,Huifen; Li,Yongqi.
Background: WNT4 is a protein that plays a crucial role in ovarian differentiation and development in mammals, with a relatively well understood function in mammalian gonadal differentiation. The role of WNT4 in teleost fish; however, remains unclear. In the present study, cDNAs of Wnt4a and Wnt4b were cloned and characterized in the spotted scat. The expression patterns of two Wnt4 genes in the gonads at different stages of development and in fish after treatment with 17a-methyltestosterone (MT) were investigated. Results: The tissue distribution showed that Wnt4a was expressed in various tissues, including the gonads, gills, spleen, brain, and fin. Interestingly, Wnt4b not only was expressed in the gills, brain, and spleen, but also was obviously...
Tipo: Journal article
Palavras-chave: Androgen; Expression patterns; Scatophagus argus; Tissue expression; Wnt4.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000200004

Problem solving in enzyme biocatalysis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Acevedo,Fernando.
Tipo: Journal article
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000400001

Effect of different metals on protease activity in sunflower cotyledons
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pena,Liliana B.; Tomaro,María L.; Gallego,Susana M.
Tipo: Journal article
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300016

Evaluation of genetic diversity and linkage disequilibrium in Korean-bred rice varieties using SSR markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Xiao-Qiang; Kwon,Soon-Wook; Park,Yong-Jin.
Background: In order to evaluate the variation among different rice types, the genetic diversity in a rice collection composed by 59 breeding lines, 23 landraces, 18 weedy rice lines, and 35 introduced lines that collected from countries worldwide was analyzed using 134 simple sequence repeat markers. Results: In total, 1264 alleles were identified (average, 9.43 per locus). Rare alleles made up a large portion (58.4%) of the detected alleles, and 29 unique alleles associated with rice accessions were also discovered. A model-based structural analysis revealed the presence of three subpopulations. The genetic relationships revealed by the neighbour-joining tree method were fairly consistent with the structure-based membership assignments for most of the...
Tipo: Journal article
Palavras-chave: Landraces; Linkage disequilibrium; Population structure; Rice; Simple sequence repeats.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500011

Globalisation, a new paradigm
Provedor de dados: Electronic Journal of Biotechnology
Autores: Acevedo,Fernando.
Tipo: Journal article
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100001

Pleiotropic effects of the sdw1 locus in barley populations representing different rounds of recombination
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kuczy&amp;#324;ska,Anetta; Miko&amp;#322;ajczak,Krzysztof; &amp;#262;wiek,Hanna.
Background In the present study populations, representing different rounds of recombination were used for the analysis of phenotypic effects associated with the sdw1/denso locus. Other studies have mostly focused only on one type of population. Many different QTLs mapped at the same position as the sdw1/denso locus may indicate a pleiotropy of this gene or a tight linkage between genes conditioning quantitative traits. To date, results of studies have not unequivocally proven either of these two phenomena. Results Both breeding and molecular mapping experiments were undertaken to examine 200 single seed descent (SSD) and 60 doubled haploid (DH) lines obtained from the Maresi (with a semi-dwarfing gene) and Pomo cross combination. They were evaluated for...
Tipo: Journal article
Palavras-chave: DH; Hordeum vulgare L; Quantitative traits; Semi-dwarfing gene; SSD; SSR markers.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000500005

Genetic diversity among native varieties and commercial cultivars of Solanum tuberosum ssp. tuberosum L. present in Chile
Provedor de dados: Electronic Journal of Biotechnology
Autores: Solano,Jaime; Mathias,Monica; Esnault,Florence; Brabant,Philippe.
Background: The object of this work was to determine the genetic and allelic diversity of Solanum species present in Chile, assessing allelic distribution among native varieties and commercial cultivars of Solanum tuberosum ssp. tuberosum L., using microsatellite markers. Results: A high level of allelic richness was found in the potatoes studied. The seven microsatellite markers used presented a total of 64 allelic variants among native varieties and commercial cultivars of Solanum tuberosum ssp. tuberosum. The SSR loci generated an average of 9.16 alleles/locus. The group with the highest PIC was that of native varieties collected in the Chiloe archipelago. The high PIC values found indicate that the native varieties from Chiloe have a low level of...
Tipo: Journal article
Palavras-chave: Dendrogram; Germplasm; SSR markers.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600008

Aspergillus kawachii produces an inulinase in cultures with yacon (Smallanthus sonchifolius) as substrate
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chesini,Mariana; Neila,Lorena Paola; de la Parra,Dante Fratebianchi; Rojas,Natalia Lorena; Contreras Esquivel,Juan Carlos; Cavalitto,Sebastian Fernando; Ghiringhelli,Pablo Daniel; Hours,Roque Alberto.
Background: Inulinases have been extracted and characterized from inulin-storing tissues; however, production of microbial inulinases have recently draw much attention as they offer several industrial advantages. Many microorganisms, including filamentous fungi, yeast and bacteria have been claimed as inulinase producers. These hydrolases are usually inducible and their exo-acting forms may hydrolyze fructose polymers (inulin) and oligosaccharides such as sucrose and raffinose. Fungal inulinase extracts are often produced as stable mixture of highly active fructanhydrolases. From a practical prospective, the best known inulinases to date are those produced by species of Penicillium, Aspergillus and Kluyveromyces. Results: The production of extracellular...
Tipo: Journal article
Palavras-chave: Acidophilic enzymes; Batch cultures; Inulin degradation; Submerged cultures.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300008

Production of extracellular alkaline protease by new halotolerant alkaliphilic Bacillus sp. NPST-AK15 isolated from hyper saline soda lakes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ibrahim,Abdelnasser S.S; Al-Salamah,Ali A; Elbadawi,Yahya B; El-Tayeb,Mohamed A; Ibrahim,Shebl Salah Shebl.
Background Alkaline proteases are among the most important classes of industrial hydrolytic enzymes. The industrial demand for alkaline proteases with favorable properties continues to enhance the search for new enzymes. The present study focused on isolation of new alkaline producing alkaliphilic bacteria from hyper saline soda lakes and optimization of the enzyme production. Results A new potent alkaline protease producing halotolerant alkaliphilic isolate NPST-AK15 was isolated from hyper saline soda lakes, which affiliated to Bacillus sp. based on 16S rRNA gene analysis. Organic nitrogen supported enzyme production showing maximum yield using yeast extract, and as a carbon source, fructose gave maximum protease production. NPST-AK15 can grow over a...
Tipo: Journal article
Palavras-chave: Alkaline protease; Alkalophiles; Bacillus sp; Fermentation; Optimization.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300015

Dynamic Cr(III) uptake by Macrocystis pyrifera and Undaria pinnatifida biomasses
Provedor de dados: Electronic Journal of Biotechnology
Autores: Plaza Cazón,Josefina; Viera,Marisa; Donati,Edgardo.
Background: The increased industrial activity has resulted in the discharge of large amount of pollutants including non-degradable metals into the environment. Chromium is produced in several industrial processes and it can be found in the environment in two stable oxidation states, Cr(VI) and Cr(III). Cr(VI) is more hazardous due to its carcinogenic and mutagenic effects on living organisms. Although much less toxic, Cr(III) can also exert genotoxic effects under prolonged or severe exposure. It can be separated from the solution by precipitation but biosorption using brown algae seems to be an effective and sustainable treatment technique owing to its cost-effectiveness and environmental friendly characteristics. Macrocystis pyrifera and Undaria...
Tipo: Journal article
Palavras-chave: Biosorption; Brown algae; Chromium; Heavy metals.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300006

Effects of substrates and reaction conditions on production of cyclodextrins using cyclodextrin glucanotransferase from newly isolated Bacillus agaradhaerens KSU-A11
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ibrahim,Abdelnasser S.S; El-Tayeb,Mohamed A; Elbadawi,Yahya B; Al-Salamah,Ali A.
The effects of reaction conditions on cyclodextrins (CDs) production by CGTase from newly isolated Bacillus agaradhaerens KSU-A11 is reported. Among six types of starch tested, potato starch gave highest starch conversion into CDs. In addition, CDs yield was about three fold higher when using gelatinized potato starch in comparison to raw starch. The total CDs production was increased with increasing pH, showing maximum starch conversion at pH 10. Furthermore, the proportion of &amp;#947;-CD was relatively higher under slightly acidic-neutral conditions than at alkaline pH with a maximum proportion of 35.6% at pH 7 compared to 7.6% at pH 10. Maximum starch conversion into CDs was seen at reaction temperature of 55ºC. Lower reaction temperature led to...
Tipo: Journal article
Palavras-chave: Bacillus agaradhaerens; Cyclodextrin glucanotransferase; Cyclodextrinc; Enzymatic reaction; Starch.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500004

Somatic embryogenesis and plant regeneration capacity in Argentinean maize (Zea mays L.) inbred lines
Provedor de dados: Electronic Journal of Biotechnology
Autores: González,Germán Andrés; Pacheco,María Gabriela; Oneto,Cecilia Décima; Etchart,Valeria J; Kandus,Mariana V; Salerno,Juan Carlos; Eyherabide,Guillermo; Presello,Daniel; Lewi,Dalia Marcela.
Somatic embryogenesis, which is still the method of choice for tissue culture, regeneration and transformation of maize, is largely considered highly genotype-dependent. The Hi II, a highly embryogenic genotype, has been extensively used in transformation protocols. However, this is not an inbred line; instead, it has a proportion of the undesirable A-188 background, and the progeny segregates for phenotypic characteristics and shows poor agronomic performance. In an effort to identify genotypes that combine a high somatic embryogenic response and good agronomic performance, we evaluated 48 advanced inbred lines developed at INTA. Callus development and somatic embryogenesis capacity were measured in 200 immature embryos per line. Embryogenic capacity [EC...
Tipo: Journal article
Palavras-chave: Callus; Inbred lines; Maize; Molecular markers; Regeneration; Somatic embryogenesis.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000100009

Active anti-acetylcholinesterase component of secondary metabolites produced by the endophytic fungi of Huperzia serrata
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Zhejian; Ma,Zhao; Wang,Lili; Tang,Chengchen; Hu,Zhibi; Chou,GuiXin; Li,Wankui.
Background An endophytic fungus lives within a healthy plant during certain stages of, or throughout, its life cycle. Endophytic fungi do not always cause plant disease, and they include fungi that yield different effects, including mutual benefit, and neutral and pathogenic effects. Endophytic fungi promote plant growth, improve the host plant's resistance to biotic and abiotic stresses, and can produce the same or similar biologically active substances as the host. Thus, endophytic fungal products have important implications in drug development. Result Among the numerous endophytic fungi, we identified two strains, L10Q37 and LQ2F02, that have anti-acetylcholinesterase activity, but the active compound was not huperzine A. The aim of this study was to...
Tipo: Journal article
Palavras-chave: Anti-acetylcholinesterase activity; Acetylcholinesterase inhibitor; Biological characteristics; Endophytic fungi.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600003

Experimental and bioinformatic approaches for analyzing and visualizing cyanobacterial nitrogen and hydrogen metabolism
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wünschiers,Röbbe; Axelsson,Rikard; Vellguth,Martin; Lindblad,Peter.
Many cyanobacteria are capable of utilizing light energy for nitrogen fixation. As a by-product of this nitrogenase mediated catalysis, hydrogen gas is produced. Several approaches to increase hydrogen production from cyanobacteria exist. Usually, these approaches are non-targeted. Here we exemplify how DNA-microarray based gene-expression analysis and bioinformatic visualization techniques can be used to analyze nitrogen and hydrogen metabolism from the filamentous, heterocyst forming cyanobacterium Nostoc PCC 7120. We analyzed the expression of 1249 genes from major metabolic categories under nitrogen fixing and non-nitrogen fixing growth. Of the selected genes, 494 show a more than 2-fold expression difference in the two conditions analyzed. Under...
Tipo: Journal article
Palavras-chave: Bioinformatics; Cyanobacteria; DNA-microarrays; Gene expression; Metabolic pathways; Nitrogen availability; Nitrogen fixation.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400008

Genetic and metabolic engineering
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yang,Yea-Tyng; Bennett,George N; San,Ka-Yiu.
Recent advances in molecular biology techniques, analytical methods and mathematical tools have led to a growing interest in using metabolic engineering to redirect metabolic fluxes for industrial and medical purposes. Metabolic engineering is referred to as the directed improvement of cellular properties through the modification of specific biochemical reactions or the introduction of new ones, with the use of recombinant DNA technology (&lt;A HREF="#56"&gt;Stephanopoulos, 1999&lt;/A&gt;). This multidisciplinary field draws principles from chemical engineering, biochemistry, molecular and cell biology, and computational sciences. The aim of this article is to give an overview of the various strategies and tools available for metabolic engineers and to...
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000300003

Use of molecular markers and major genes in the genetic improvement of livestock
Provedor de dados: Electronic Journal of Biotechnology
Autores: Montaldo,Hugo H.; Meza-Herrera,Cesar A.
Recent developments in molecular biology and statistics have opened the possibility of identifying and using genomic variation and major genes for the genetic improvement of livestock. Information concerning the basis of these techniques and their applications to the genetic improvement of animals is reviewed. Main marker molecular marker systems in animals (RFPL and microsatellites), genome maps, methods for detecting marker major gene linkages and use of marker assisted selection, genetic fingerprinting and mixture models based on segregation analysis are analyzed. The characteristics where the application of marker assisted selection can be more effective are those that are expressed late in the life of the animal, or controlled by a few pairs of genes....
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000200004

In vitro regeneration and genetic fidelity of Tigridia pavonia (L.f.) DC.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Piña-Escutia,José Luis; Vázquez-García,Luis Miguel; Arzate-Fernández,Amaury Martín.
Plants of Tigridia pavonia (L.f.) DC were regenerated from twin-scaling explants cultured on Murashige and Skoog and N6 basal medium. The highest formation of shoots per responding explant was obtained on N6 medium supplemented with 4.5 µM 2,4-dichlorophenoxy acetic acid in combination with 2.2 µM benzylaminopurine. Shoots rooted readily on N6 basal medium supplemented with 1 g l-1 activated charcoal and 2.6 µM naphtalenacetic acid. The rooted shoots achieved 100% survival. Inter Simple Sequence Repeat analysis was carried out to check for possible genetic alterations in plants obtained after two consecutive subcultures. The results revealed that the recovered plants did not exhibit any type of polymorphism.
Tipo: Journal article
Palavras-chave: Genetic integrity; Micropropagation; Oceloxóchitl.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100007

Expression and non-chromatographic purification of 1,3-propanediol oxidoreductase in Escherichia coli
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Wei; Ng,I-Son; Fang,Baishan; Zhang,Guangya.
The gene dhaT from Klebsiella pneumoniae encodes 1,3-propanediol oxidoreductase (PDOR). Thermally responsive elastin-like polypeptides (ELPs) was used as a fusion tag to purify the proteins (PDOR). The ELP gene was attached to dhaT and ligated into the pET-22b vector. Different NaCl concentrations were employed to decrease the transition temperature (Tt) which was diminished as salt concentration increased. The optimal final concentration of NaCl was 1 M and the corresponding Tt was 39.5ºC. Enzymatic assays were determined via every step for purification of fusion PDOR. PDOR showed good stability during the purification process, the specific activity in the first and second round of inverse transition cycling (ITC) was 276.1 ± 13.3 and 213.3 ± 10.8 U/mg,...
Tipo: Journal article
Palavras-chave: 1; 3-propanediol oxidoreductase elastin-like polypeptides Escherichia coli fusion protein non-chromatographic purification.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600010

Potential of giant reed (Arundo donax L.) for second generation ethanol production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lemons e Silva,Claudia Fernanda; Artigas Schirmer,Manoel; Nobuyuki Maeda,Roberto; Araújo Barcelos,Carolina; Pereira,Nei.
Background The production of second generation ethanol from lignocellulosic biomasses that have not had their potential fully explored as feedstock is of great importance. Arundo donax is one these biomasses. It is a promising grassy plant to be used as a renewable resource for the production of fuels and chemicals, because of its fast growth rate, ability to grow in different soil types and climatic conditions. The present study evaluated its use as feedstock for the production of second generation ethanol. Results Initially its chemical characterization was carried out, and a protocol for fractioning the biomass through diluted acid pretreatment followed by alkaline pretreatment was developed, providing a solid fraction which was undergone to enzymatic...
Tipo: Journal article
Palavras-chave: Acid and alkaline pretreatments; Alcohol fermentation; Cellulase; Enzymatic hydrolysis; Lignocellulose.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100003

New molecular biologist perspective and insight: DNA topoisomerases production by recombinant DNA technology for medical laboratory application and pharmaceutical industry
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chan,Mooi Kwai; Fadzil,Nur Adila; Chew,Ai Lan; Khoo,Boon Yin.
DNA topoisomerases are essential enzymes that control the topological state of DNA replication during mitosis. These enzymes are classified based on their mechanisms and physical properties. During mitosis, superhelical DNA must be unwound or relaxed by DNA topoisomerases prior to a decoding step by DNA processing enzymes, such as DNA polymerase and RNA polymerase. By blocking the reaction of resealing the breaks in the DNA ultimately can result in cellular death. Compounds that inhibit the catalytic function of these enzymes can serve as potential anticancer agents. DNA topoisomerases are found in nature and used as high quality and well-validated targets for the screening of potential anticancer agents. Our current work focuses on determining potential...
Tipo: Journal article
Palavras-chave: DNA topoisomerase; Medical laboratory application; Pharmaceutical industry; Recombinant DNA technology.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600018

Identification of SSR markers using soybean (Glycine max) ESTs from globular stage embryos
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Ai Qin; Zhao,Chuan Zhi; Wang,Xing Jun; Liu,Zhan Ji; Zhang,Li Feng; Song,Guo Qi; Yin,Juan; Li,Chang Sheng; Xia,Han; Bi,Yu Ping.
Microsatellites, or simple sequence repeats (SSRs), in expressed sequence tags (ESTs) provide an opportunity for low cost SSR development. We looked for EST-SSRs in 403,511 ESTs (generated by 454 sequencing and representing 70,654 contigs and 52,082 singletons) from soybean globular stage embryos. Among 122,736 unique ESTs, 3,729 contained one or more SSRs. In total, 3,989 SSRs were identified including 304 mono, 1,374 di, 2,208 tri, 70 tetra, 13 penta and 20 hexanucleotide SSRs. Thirty three EST-SSRs were selected for primer design and polymorphism analysis using twenty soybean cultivars and one wild-type soybean. Successful amplification was obtained using 21 of these primer pairs, 11 of which detected polymorphisms in these soybean cultivars. These...
Tipo: Journal article
Palavras-chave: 454 sequencing; EST; Glycine max; Polymorphism; SSR.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500006

Agrobacterium tumefaciens: a natural tool for plant transformation
Provedor de dados: Electronic Journal of Biotechnology
Autores: de la Riva,Gustavo A; González-Cabrera,Joel; Vázquez-Padrón,Roberto; Ayra-Pardo,Camilo.
Updated information of mechanisms for T-DNA transfer to plant cells by Agrobacterium tumefaciens is provided, focused on the role played by the different components of the virulence system. The general assessments for the establishment of efficient transformation protocols are discussed with an emphasis in the application of this methodology to monocotyledonous plants. Based on our own experience, we present the establishment of sugarcane transformation by A. tumefaciens as a model of application of this methodology to an important culture plant species, previously considered recalcitrant and inaccessible for this type of genetic manipulation.
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000300002

Novel antiviral activity of dialdehyde starch
Provedor de dados: Electronic Journal of Biotechnology
Autores: Song,Le; Cruz,Caroline; Farrah,Samuel R; Baney,Ronald H.
A significant effort worldwide is being directed toward development of novel biocides against drug-resistant bacterial and viruses because of the significant potential human infection risks in the general population. We report here the discovery of a strong antiviral biocide, dialdheyde starch (DAS). Antiviral tests were carried out against three non-envelop viruses, including two bacterial viruses MS2 and PRD1, and one human virus Poliovirus. Dialdehyde starch aqueous suspensions were effective biocides against these three test viruses in a 1 hr exposure test. The antiviral activity was significantly enhanced in a four-hour exposure test, with maximum seven orders of magnitude reductions against MS2 and PRD1, and four-order reduction against Poliovirus....
Tipo: Journal article
Palavras-chave: Antiviral; Biocide; Dialdehyde starch; Virus.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200013

Metal hyperaccumulation in plants: Biodiversity prospecting for phytoremediation technology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vara Prasad,Majeti Narasimha; de Oliveira Freitas,Helena Maria.
The importance of biodiversity (below and above ground) is increasingly considered for the cleanup of the metal contaminated and polluted ecosystems. This subject is emerging as a cutting edge area of research gaining commercial significance in the contemporary field of environmental biotechnology. Several microbes, including mycorrhizal and non-mycorrhizal fungi, agricultural and vegetable crops, ornamentals, and wild metal hyperaccumulating plants are being tested both in lab and field conditions for decontaminating the metalliferous substrates in the environment. As on todate about 400 plants that hyperaccumulate metals are reported. The families dominating these members are Asteraceae, Brassicaceae, Caryophyllaceae, Cyperaceae, Cunouniaceae, Fabaceae,...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300012

Antimicrobial effects of plant defence peptides expressed by bovine endothelial cells on intracellular pathogens
Provedor de dados: Electronic Journal of Biotechnology
Autores: Loeza-Ángeles,Heber; López-Meza,Joel E; Ochoa-Zarzosa,Alejandra.
Background: The actions of plant antimicrobial peptides (PAP) against intracellular pathogens are poorly known. It has been reported that wheat puroindolines show antibacterial activity against Staphylococcus epidermidis endocyted by macrophages. In this work, we evaluated the intracellular antimicrobial activity of PAP gamma-thionin and thionin Thi2.1 produced by bovine endothelial cells against intracellular Staphylococcus aureus and Candida albicans. We used three host-pathogen models: 1) bovine mammary epithelial cells (BMEC)-S. aureus, 2) bovine endothelial cells (BEC)-S. aureus and 3) BEC-C. albicans, and evaluated the effect of conditioned media from BEC producers of PAP (gamma-thionin and thionin Thi2.1). Results: In the first model, conditioned...
Tipo: Journal article
Palavras-chave: Antimicrobial peptides; Arabidopsis thaliana thionin; Capsicum chinense gamma-thionin; Candida albicans; Intracellular pathogens; Staphylococcus aureus.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500001

Comparison of whole-genome amplifications for microsatellite genotyping of Rotylenchulus reniformis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Arias,Renée S; Stetina,Salliana R; Scheffler,Brian E.
Currently, a large number of microsatellites are available for Rotylenchulus reniformis (reniform nematode); however, two barriers exist for genotyping samples from different geographical areas. The limited amount of nucleic acids obtained from single nematodes which would require their multiplication to obtain enough DNA for testing; and the strictly regulated transport of live samples and multiplication in greenhouse for being a plant pathogen. Whole-genome amplification (WGA) of samples consisting of one and five dead gravid females with their associated egg masses was successfully performed on disrupted tissue using three commercial kits. DNA yield after WGA ranged from 0.5 to 8 Âµg and was used to test 96 microsatellite markers we previously developed...
Tipo: Journal article
Palavras-chave: Genotyping; Reniform nematode; SSR; STR; WGA.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300014

Novel s-triazine-degrading bacteria isolated from agricultural soils of central Chile for herbicide bioremediation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hernández García,Marcela; Morgante,Verónica; Ávila Perez,Marcela; Villalobos Biaggini,Patricio; Miralles Noé,Pola; González Vergara,Myriam; Seeger Pfeiffer,Michael.
s-Triazine-degrading bacterial strains were isolated from long-term simazine-treated agricultural soils of central Chile. The number of culturable heterotrophic bacteria of these agricultural soils (7 x 10(6) CFU/g of dry soil) was not affected by simazine application on field. The simazine-degrading bacterial strains P51, P52 and C53 were isolated by enrichment in minimal medium using simazine as the sole nitrogen source. Resting cells of strains P51 and P52 degraded &gt;80% of simazine within 48 hrs, whereas strain C53 was able to remove &gt;60% of the herbicide. The atzA and atzD genes of the s-triazine upper and lower catabolic pathways were detected in strains P51 and C53, while only atzD gene was observed in strain P52. To compare the bacterial 16S...
Tipo: Journal article
Palavras-chave: Arthrobacter; Biodegradation; Bioremediation; Simazine; Stenotrophomonas; S-triazine.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000500005

Nutrient enrichment of cassava peels using a mixed culture of Saccharomyces cerevisae and Lactobacillus spp solid media fermentation techniques
Provedor de dados: Electronic Journal of Biotechnology
Autores: Oboh,Ganiyu.
Cassava pulp was fermented with pure strains of Saccharomyces cerevisae and two bacteria namely Lactobacillus delbruckii and Lactobacillus coryneformis for 3 days. The squeezed liquid from the fermented pulp was used to ferment cassava peels for 7 days. Analysis of the dried fermented peels revealed that there was a significant (P &lt; 0.05) increase in the protein content of the cassava peels fermented with squeezed liquid from the inoculated cassava pulp (21.5%) when compared with the unfermented cassava peel (8.2%). Moreover, the treatment equally brought about a significant (P &lt; 0.05) decrease in the cyanide (6.2 mg/kg) and phytate content (789.7 mg/100g) when compared with the unfermented cassava peels, which had 44.6 mg/kg cyanide and 1043.6...
Tipo: Journal article
Palavras-chave: Cassava peels; Cyanide; Fermentatio; Protein.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100007

Sucrose hydrolysis catalyzed by auto-immobilized invertase into intact cells of Cladosporium cladosporioides
Provedor de dados: Electronic Journal of Biotechnology
Autores: Santana de Almeida,Ana Cláudia; Costa de Araújo,Luciares; Mendes Costa,Andressa; Moraes de Abreu,César Augusto; Gomes de Andrade Lima,Maria Alice; Perez Fernandez Palha,Maria de Los Angeles.
The enzyme known as invertase (E.C. 3.2.1.26 - &amp;#946;-D-fructofuranosidase) catalyzes the sucrose hydrolysis producing an equimolar mixture of glucose and fructose named inverted sugar. The fungus Cladosporium cladosporioides has invertase as its constituent. Hence, its use as a natural immobilized support for the invertase produces interesting results for the enzyme. The present work has the objective of determining the optimum operational conditions of auto-immobilized invertase, as well as its kinetic parameters (K M and Vmax). A complete 2³ factorial planning was done for the evaluation of such parameters. Temperature, pH and agitation level were the studied variables. The hydrolysis percentage was the monitored result. Batch tests in optimum...
Tipo: Journal article
Palavras-chave: Cladosporium cladosporioides; Factorial planning; Invertase.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100009

Lactic acid production by a strain of Lactococcus lactis subs lactis isolated from sugar cane plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Serna Cock,Liliana; Rodríguez de Stouvenel,Aida.
A Lactococcus lactis subs lactis strain was selected from 20 lactic acid strains isolated from the leaves of sugar cane plants, variety CC 85-92. The effects of substrate concentration and pH control on lactic acid (LA) production, glucose conversion (GC) and yield (Yp/s) were investigated using this strain. In batch fermentation at 32&amp;ordm;C, with 60 gl-1 of glucose and a pH of 6.0, concentrations of up to 35 gl-1 of lactic acid were obtained. Maximum production and glucose conversion was achieved at low glucose concentrations. The strain shows great potential for lactic acid production from glucose, even without using pH control during fermentation (13.7 gl-1)
Tipo: Journal article
Palavras-chave: CC 85-92; Leaves of sugar cane; PH control; Substrate concentration.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100006

Genotypic variation in morphology and freezing resistance of Eucalyptus globulus seedlings subjected to drought hardening in nursery
Provedor de dados: Electronic Journal of Biotechnology
Autores: Coopman,Rafael E; Jara,Jorge C; Escobar,Rene; Corcuera,Luis J; Bravo,Leon A.
Eucalyptus globulus Labill is one of the most planted species in Chile, because of its fast growth and superior pulp qualities. Nevertheless, the incidence of drought and frost damage immediately after planting is frequent. The purpose of this work was to study the effect of drought hardening on frost resistance and on variations in morphological traits that may increase drought resistance at nursery phase in four genotypes of E. globulus Labill. Drought hardening treatments consisted in induced water stress by watering restriction, until pre-dawn stem xylem water potentials (&amp;#936;pd) reached -0.2, -1.8 and -2.6 MPa. Two water stress-rewatering cycles were applied during 54 days of hardening. Plant and root biomasses were affected by the interaction...
Tipo: Journal article
Palavras-chave: Biomass allocation; Cross hardening; Genotypic selection; Planting stock quality; Water stress.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100005

Globalisation and Learning
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sánchez Sorondo,Marcelo.
Tipo: Journal article
Palavras-chave: Globalisation; Education; Justice; Ethics; Synthesize knowledge.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100003

Sequence variability in p27 gene of Citrus Tristeza Virus (CTV) revealed by SSCP analysis
Provedor de dados: Electronic Journal of Biotechnology
Citrus tristeza closterovirus (CTV), is a phloem-limited virus transmitted by aphids in a semipersistent manner. The genome of CTV is composed of a ssRNA with two capsid proteins: CP, covering about 95% of the particle length, and a diverged coat protein (dCP), present only in one end of the particle, forming a rattlesnake structure. dCP is the product of p27 gene for which it is also postulated a function in the transmissibility by aphid vectors. Hybridization analysis showed a p27 gene region, which exhibits different patterns with two probes derived from two biological distinct CTV isolates. In an attempt to screen whether that gene region differs in mild and severe strains, six CTV isolates belonging to different biogroups were compared for variations...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000100005

Application of statistical experimental methods to optimize medium for exopolymer production by newly isolated Halobacterium sp. SM5
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lungmann,Patcharee; Choorit,Wanna; Prasertsan,Poonsuk.
The study investigated on medium optimization for production of exopolymer by a newly isolated bacterium, Halobacterium sp. SM5, using the mixture design and response surface method. The mixture experiment was designed by setting five parameters at the lowest and highest of concentrations: pseudo components design containing 0.15-0.25 glucose, 0.15-0.25 yeast extract, 0.35-0.45 MgSO4·7H2O, 0.1-0.2 vitamin casamino acid and 0.02-0.06 KCl. The results of the mixture design revealed that the effect of nutrients or elements on the exopolymer produced by the strain SM5 were in the order of MgSO4·7H2O &gt; yeast extract &gt; vitamin casamino acid &gt; KCl &gt; glucose, respectively. The suitable medium recipe for enhancement the exopolymer production was 7.43...
Tipo: Journal article
Palavras-chave: Exopolymer; Halophilic bacteria; Medium optimization; Mixture design; Response surface method.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100001

Cotton genetic diversity study by AFLP markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Murtaza,Naveed.
Amplified fragmentlength polymorphism (AFLP) markers have been used to ascertain the intensity of inherent diversity and relatedness in cotton (Gossypium spp.) plants. The effectiveness of this method to distinguish inter and intra specific difference in cotton could be handy in cultivar recognition and in marker assisted parental selection tool for plant breeders. Twenty cotton cultivars belonging to Gossypium hirsutum L., and G. arborium L. from the Pakistan and US origin were used for AFLP based genetic diversity estimates. The objective of this study was to assess the level of genetic variation among some cotton cultivars belonging to the old and new world species of cotton. Four EcoRI-MseI primer-pair combinations were used forthe AFLP analysis. The...
Tipo: Journal article
Palavras-chave: AFLP; Cluster analysis; Cotton; Genetic diversity; PCR.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400013

EDITORIAL
Provedor de dados: Electronic Journal of Biotechnology
Autores: Illanes,Andrés.
Tipo: Journal article
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300001

Callus induction and plant regeneration of the endemic Astragalus nezaketae in Turkey
Provedor de dados: Electronic Journal of Biotechnology
Autores: Erisen,Semiha; Yorgancilar,Mustafa; Atalay,Emine; Babaoglu,Mehmet; Duran,Ahmet.
A callus induction and plant regeneration protocol was developed from leaf and petiole explants of the endemic Astragalus nezaketae. Explants were cultured on Murashige and Skoog medium (MS) supplemented with different plant growth regulators (PGRs) [?-naphthaleneacetic acid (NAA), benzyladenine (BA), 2,4-dichlorophenoxyacetic acid (2,4-D), kinetin (Kin), thidiazuron (TDZ)]. The combinations and concentrations of PGRs were shown significant variations for the frequency of callus formation, appearence of callus and the potential of callus differentiation. NAA x BA have been found highly affective in callusing and plant regeneration. Other PGRs have not resulted in callus differentiation for shoot formation. The highest number of shoots (6/explants) was...
Tipo: Journal article
Palavras-chave: Astragalus; Callus; Organogenesis; Plant regeneration.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600013

Growth of Cunninghamella elegans UCP 542 and production of chitin and chitosan using yam bean medium
Provedor de dados: Electronic Journal of Biotechnology
Autores: Stamford,Thayza Christina Montenegro; Stamford,Tânia Lucia Montenegro; Stamford,Newton Pereira; Barros Neto,Benicio de; Campos-Takaki,Galba Maria de.
Microbiological processes were used for chitin and chitosan productions by Cunninghamella elegans (UCP 542) grown in a new economic culture medium. The assay was carried out to evaluate the growth of C. elegans using yam bean (Pachyrhizus erosus L. Urban) medium, in different times of growth (24, 48, 72 and 96 hrs), incubated at 28ºC in an orbital shaker at 150 rpm. The lyophilized biomass was determined by gravimetry. The polysaccharides were extracted by alkali-acid treatment, and characterized by infrared spectroscopy, titration and viscosity. C. elegans grown in the yam bean medium and produced higher yields of biomass (24.3 g/ mL) in 96 hrs. The high level was chitosan (66 mg/g), and chitin (440 mg/g) were produced at 48 and 72 hrs of growth,...
Tipo: Journal article
Palavras-chave: Biopolymers; Chitin; Chitosan.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100006

Yeast lipases: enzyme purification, biochemical properties and gene cloning
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vakhlu,Jyoti.
Lipases are placed only after proteases and carbohydrases in world enzyme market and share about 5% of enzyme market. They occur in plants, animals and microorganisms and are accordingly classified as plant, animal and microbial lipases. Wherever they exist, they function to catalyze hydrolysis of triglycerides to glycerol and fatty acid. Like carbohydrases and proteases, lipases of microbial origin enjoy greater industrial importance as they are more stable (compared to plant and animal lipases) and can be obtained in bulk at low cost. Majority of yeast lipases are extracelluar, monomericglycoproteins with molecular weight ranging between ~33 to ~65 kD. More than 50% reported lipases producing yeast, produce it in the forms of various isozymes. These...
Tipo: Journal article
Palavras-chave: Candida; Geotrichum; Lipase; Trichosporon; Yeast.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100010

PPAR&amp;#947;, FAS, HSL mRNA and protein expression during Tan sheep fat-tail development
Provedor de dados: Electronic Journal of Biotechnology
Autores: Xu,Xiaochun; Wei,Xuan; Yang,Yuxin; Niu,Wenzhi; Kou,Qifang; Wang,Xiaolong; Chen,Yulin.
Background The objective of this study was to investigate proliferator-activated receptor (PPAR&amp;#947;), fatty acid synthase (FAS) and hormone-sensitive lipase (HSL) mRNA and protein expression in fat tails of Tan sheep. Rams from different developmental stages (aged 3, 6, 9, 12, 15 and 18 months) were selected, and their tail measurements including length (L), width (W) and girth (G) were recorded. The mRNA and protein expressions of PPAR&amp;#947;, FAS and HSL were examined by quantitative real-time polymerase chain reaction (PCR) and Western blot. Results The tail measurements increased with age. We observed no significant differences (P &amp;gt; 0.05) of PPAR&amp;#947; mRNA expression between ages 9 and 15 months, and between 12 and 15 months; FAS...
Tipo: Journal article
Palavras-chave: Fat-tailed sheep; MRNA transcription; Protein expression; Transcription factor and enzyme genes.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200010

Elevating the expression level of biologically active recombinant human alpha 1-antitrypsin in Pichia pastoris
Provedor de dados: Electronic Journal of Biotechnology
Autores: Arjmand,Sareh; Lotfi,Abbas Sahebghadam; Shamsara,Mehdi; Mowla,Seyed Javad.
Background: Human alpha 1-antitrypsin (AAT) is a potent inhibitor of multiple serine proteases, and protects tissues against their harmful effects. Individuals with reduced or abnormal production of this inhibitor need intravenous administration of exogenous protein. In this study, we employed the methylotrophic (methanol utilizing) yeast Pichia pastoris (P. pastoris) as a preferential host for efficient production and secretion of recombinant AAT. Furthermore, we examined different strategies to maximize the yield of the secreted protein. Results: Our findings revealed that optimizing the codon usage of AAT gene for P. pastoris had positive effects on the level of secreted AAT under the control of inducible alcohol oxidase 1 (AOX1) and constitutive...
Tipo: Journal article
Palavras-chave: Human alpha 1-antitrypsin; Pichia pastoris; Recombinant proteins.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000100004

Genetic variability for waxy genes in Argentinean bread wheat germplasm
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vanzetti,Leonardo Sebastián; Pflüger,Laura Alicia; Rodríguez-Quijano,Marta; Carrillo,José Maria; Helguera,Marcelo.
Amylose and amylopectin are the two polysaccharides that constitute starch in bread wheat and the enzyme GBSSI (Granule-bound starch synthase I), also known as waxy protein, is responsible for amylose synthesis in storage tissues. Decrease of the amylose content in starch has been associated with the lack of waxy protein(s). In this work, different sets of PCR markers were used to characterize the genetic variability of waxy loci from 103 Argentinean bread wheat cultivars. For the Wx-A1 locus, Wx-A1a and a novel molecular allele designed Wx-A1g were detected. Wx-B1 locus showed three alleles (Wx-B1a, Wx-B1b, Wx-B1e), and Wx-D1 locus showed only the Wx-D1a allele. Novel single-locus allele specific markers for Wx-A1b, Wx-B1b and Wx-D1b null alleles were...
Tipo: Journal article
Palavras-chave: Characterization; Molecular markers; Triticum aestivum L.; Starch; Waxy genes; Wheat.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000100004

A simple and efficient method for extraction of Taq DNA polymerase
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chen,Sique; Zheng,Xiujuan; Cao,Hongrui; Jiang,Linghui; Liu,Fangqian; Sun,Xinli.
Background Thermostable DNA polymerase (Taq Pol ?) from Thermus aquaticus has been widely used in PCR, which was usually extracted with Pluthero's method. The method used ammonium sulfate to precipitate the enzyme, and it saved effort and money but not time. Moreover, we found that 30-40% activity of Taq Pol I was lost at the ammonium sulfate precipitation step, and the product contained a small amount of DNA. Results We provided a novel, simplified and low-cost method to purify the Taq Pol ? after overproduction of the enzyme in Escherichia coli, which used ethanol instead of ammonium sulfate to precipitate the enzyme. The precipitate can be directly dissolved in the storage buffer without dialysis. In addition, DNA and RNA contamination was removed with...
Tipo: Journal article
Palavras-chave: Ethanol precipitation; PCR; Purification; Taq DNA polymerase.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500005

Copolymerization of lignin with cresol catalysed by peroxidase in reversed micellar systems
Provedor de dados: Electronic Journal of Biotechnology
Autores: Liu,Junhong; Ye,Lin; Weiping,Yuan.
Peroxidase catalysed copolymerization of lignin with cresol in a reversed micellar system was performed successfully. The molecular weight of the copolymer was controlled by adjusting the surfactant concentration and a maximal mean molecular weight of 1890 kDa was obtained.
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000200004

Root induction in radiata pine using Agrobacterium rhizogenes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Mingshan; Leung,David W.M.
Root induction using Agrobacterium rhizogenes was conducted in hypocotyl explants, intact seedlings, de-rooted seedling cuttings and adventitious shoots of radiata pine (Pinus radiata D. Don). Use of two A. rhizogenes strains (A4T and LB9402), with or without application of IBA, can trigger root formation in different explants. Strain LBA9402 was more effective than A4T in increasing rooting percentage and root number. Addition of 4.4 uMIBA to the medium further enhanced rooting from the cultured hypocotyl segments inoculated with the two A. rhizogenes strains. Strain LBA9402+IBA induced in about 75% of the cultured hypocotyl segments to form roots. In contrast the controls failed to initiate roots on intact seedlings or cultured segments in presence or...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300010

Efficiency of RAPD, ISSR, AFLP and ISTR markers for the detection of polymorphisms and genetic relationships in camote de cerro (Dioscorea spp.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Velasco-Ramírez,Ana Paulina; Torres-Morán,Martha Isabel; Molina-Moret,Sandy; Sánchez-González,José de Jesús; Santacruz-Ruvalcaba,Fernando.
Background At present, species known as camote de cerro (Dioscorea spp.) are found only in the wilderness in Mexico, but their populations are extremely depleted because they are indiscriminately collected, it is urgent to evaluate the conservation status of these plants in order to design conservation genetics programs. In this study, genetic diversity parameters along with cluster analysis based on Jaccard's coefficient were estimated with the objective to assess the efficiency of Random Amplified Polymorphic DNA (RAPD), Inter Simple Sequence Repeat (ISSR), Amplified Fragment Length Polymorphism (AFLP) and Inverse Sequence Tagged Repeat (ISTR) molecular DNA markers in the Dioscorea genus. Results The polymorphic information contents were quite similar...
Tipo: Journal article
Palavras-chave: Dioscoreaceae; Genetic diversity; Molecular markers; Tuber.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000200002

Production of polyhidroxyalkanoates by Pseudomonas putida KT2442 harboring pSK2665 in wastewater from olive oil mills (alpechín)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ribera,Rafael Garcia; Monteoliva-Sanchez,Mercedes; Ramos-Cormenzana,Alberto.
The nutritionally versatile Pseudomonas putida has showed to grow in olive oil waste water called "alpechín", which is toxic for many other microorganisms. The transformation with the plasmid pSK2665, harboring Alcaligenes eutrophus genes needed for synthesis of poly (3-hidroxybutyric acid), allow Pseudomonas strain to grow in high concentration of the wastewaters "alpechín" accumulating biodegradable thermoplastic.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200010

Microsatellite markers in candidate genes for wood properties and its application in functional diversity assessment in Eucalyptus globulus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Acuña,Cintia V; Villalba,Pamela V; García,Martín; Pathauer,Pablo; Hopp,H. Esteban; Marcucci Poltri,Susana N.
Background: Functional genetic markers have important implications for genetic analysis by providing direct estimation of functional diversity. Although high throughput sequencing techniques for functional diversity analysis are being developed nowadays, the use of already well established variable markers present in candidate genes is still an interesting alternative for mapping purposes and functional diversity studies. SSR markers are routinely used in most plant and animal breeding programs for many species including Eucalyptus. SSR markers derived from candidate genes (SSR-CG) can be used effectively in co-segregation studies and marker-assisted diversity management. Results: In the present study, eight new non reported SSRs were identified in seven...
Tipo: Journal article
Palavras-chave: Functional markers; Genetic diversity; Lignin pathway; SSR; Wood density.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000200002

Effect of free ammonia nitrogen on the methanogenic activity of swine wastewater
Provedor de dados: Electronic Journal of Biotechnology
Autores: Belmonte,Marisol; Hsieh,Chia-Fang; Figueroa,Cindy; Campos,José Luis; Vidal,Gladys.
Swine wastewater is characterized by high organic matter content, solids, nitrogen (expressed as total ammonia and protein) and heavy metals. This work determines the methanogenic toxicity effect of free ammonia contained in swine wastewater comparing raw swine wastewater (RW) and the liquid fraction of swine wastewater (TW). The values of IC50 (50% of inhibition) obtained for methanogenic bacteria ranged between 56 and 84% for RW, meanwhile IC50 for TW was ranged between 84 and 94%. Such inhibitory effects can be related to the free ammonia nitrogen concentration (&gt; 40 mg NH3-N/L) contained in swine wastewater.
Tipo: Journal article
Palavras-chave: Free ammonia nitrogen; Methanogenic activity; Swine wastewater.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300002

Immobilization and stability studies of a lipase from thermophilic Bacillus sp: The effect of process parameters on immobilization of enzyme
Provedor de dados: Electronic Journal of Biotechnology
Autores: Nawani,Neerupma; Singh,Rajvinder; Kaur,Jagdeep.
A thermostable lipase was partially purified from the culture supernatant of a thermophilic Bacillus sp. The enzyme is optimally active at 60&amp;ordm;C and pH 8.0. The enzyme showed enhancement in activity in presence of benzene or hexane (30% v/v each). The activity (assayed by determining the release of pNP from pNP laurate) was stimulated up to 60% of these solvents in enzyme reaction mixture. The catalytic properties of this thermostable enzyme can be further improved via the use of different immobilization techniques and reaction conditions. Enzyme was immobilized on different solid supports and their enzyme activity and stability was compared. The enzyme was adsorbed on silica and HP-20 beads followed by cross-linking with gluteraldehyde on HP-20,...
Tipo: Journal article
Palavras-chave: Esterification; Immobilization; Lipase; Thermostability.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500011

Gill tissues of the mussel Mytilus edulis chilensis: A new source for antimicrobial peptides
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mercado,Luis; Schmitt,Paulina; Marshall,Sergio H; Arenas,Gloria.
Antimicrobial peptides are small-sized, cationic and amphipathic molecules able to neutralize pathogenic microorganisms. Their antimicrobial effects tie them to mechanisms of immune defense, which is why they have been normally purified from immune cells. We describe an apparently new group of antimicrobial peptides from gill tissues of the mussel Mytilus edulis chilensis. 20 specimens yielded 40 g of gills which produced 16 mg of an enriched fraction with antimicrobial activity as low as 0.045 &amp;micro;g/&amp;micro;l over reference strains. Considering the chemical nature of these molecules we used an acid extraction procedure followed by consecutive cationic exchange and hydrophobic interaction chromatography steps for peptide enrichment. The resulting...
Tipo: Journal article
Palavras-chave: Antimicrobial peptides; Biochemical characterization; Gill tissues; In vitro activity; Mussels.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300008

Field defects in progression to adenocarcinoma of the colon and esophagus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bernstein,Carol; Bernstein,Harris; Payne,Claire; Garewal,Harinder.
A field of defective tissue (field defect) appears to be an early stage in the progression to adenocarcinoma of both the colon and the esophagus. In both cases the field is comprised of cells characterized by resistance to induction of apoptosis, aberrant increased proliferation and genomic instability. Specific mutations and epimutations occur in both types of field. Also there is evidence for aberrant overexpression or underexpression of specific proteins. Most of these early molecular alterations appear to promote either enhanced apoptosis resistance, proliferation, or genomic instability. The molecular alterations that are present early are often, but not always, also present to an even greater degree in the cancer itself. Many of the important events...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000300001

Catalase enzyme in mitochondria of Saccharomyces cerevisiae
Provedor de dados: Electronic Journal of Biotechnology
Autores: Petrova,Ventsislava Yankova; Rasheva,Tanya Vassileva; Kujumdzieva,Anna V.
Catalase and superoxide dismutase activities have been explored in the yeast Saccharomyces cerevisiae during batchwise growth experiment. During the diauxic growth in YPD medium high Ys values were obtained (0.415 - 0.423) and correlation between the total activities of both enzymes has been found. A mitochondrial fraction from three type strains of Saccharomyces cerevisiae has been isolated. The purity of this fraction was proved through different enzyme assays: hexokinase, glucose-6-phosphate dehydrogenase, D-amino acid oxidase, isocitric lyase, succinate dehydrogenase. Then the catalase, peroxidase, Mn and Cu/Zn superoxide dismutase activities were evaluated in the mitochondrial fraction. Polyacrylamide gel electrophoresis separations allowed to...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100010

Oxygen mass transfer studies on batch cultivation of P. aeruginosa in a biocalorimeter
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sivaprakasam,Senthilkumar; Mahadevan,Surianarayanan; Gopalaraman,Swaminathan.
In the present work volumetric mass transfer coefficient (kLa) was investigated during batch cultivations of Pseudomonas aeruginosa on a nutrient media. The effects of process variables (viz. impeller speed, oxygen flow and geometry of impeller) on the volumetric mass transfer coefficient of oxygen, kLa, in a biocalorimeter (Bio-RC1) was investigated and reported in this research work. The experimental data have been analyzed employing MATLAB to obtain the influences of the process parameters on kLa. An attempt was made to correlate volumetric mass transfer coefficient with metabolic heat production rate at optimized process conditions. The correlation reported in this work would be useful to control and scale up of bioprocesses.
Tipo: Journal article
Palavras-chave: Biocalorimeter; Metabolic heat; P. aeruginosa; Scale-up; Volumetric mass transfer coefficient.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100008

Bioprospection of cellulolytic and lipolytic South Atlantic deep-sea bacteria
Provedor de dados: Electronic Journal of Biotechnology
Autores: Odisi,Estácio Jussie; Silvestrin,Marcela Bruschi; Takahashi,Rodrigo Yoji Uwamori; da Silva,Marcus Adonai Castro; Lima,André Oliveira de Souza.
Background: Cellulases and lipases have broad industrial application, which calls for an urgent exploration of microorganisms from extreme environments as valuable source of commercial enzyme. In this context, the present work describes the bioprospection and identification of deep-sea bacteria that produce cellulases and lipases, as well their optimal temperature of activity. Results: The first step of this study was the screening of cellulolytic and lipolytic deep-sea bacteria from sediment and water column, which was conducted with substrates linked with 4-Methylumbelliferyl. Among the 161 strains evaluated, 40 were cellulolytic, 23 were lipolytic and 5 exhibited both activities. Cellulolytic and lipolytic bacteria are more common in sediment than at...
Tipo: Journal article
Palavras-chave: Bacteria; Cellulases; Deep-sea; Lipases.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500018

Over-expression of CYP78A98, a cytochrome P450 gene from Jatropha curcas L., increases seed size of transgenic tobacco
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tian,Yinshuai; Zhang,Min; Hu,Xiaole; Wang,Linghui; Dai,Jiao; Xu,Ying; Chen,Fang.
Background: Jatropha curcas L. (further referred to as Jatropha), as a rapidly emerging biofuel crop, has attracted worldwide interest. However, Jatropha is still an undomesticated plant, the true potential of this shrub has not yet been fully realized. To explore the potential of Jatropha, breeding and domestication are needed. Seed size is one of the most important traits of seed yield and has been selected since the beginning of agriculture. Increasing the seed size is a main goal of Jatropha domestication for increasing the seed yield, but the genetic regulation of seed size in Jatropha has not been fully understood. Results: We cloned CYP78A98 gene from Jatropha,a homologue of CYP78A5 in Arabidopsis.Wefound that CYP78A98 was highly expressed in male...
Tipo: Journal article
Palavras-chave: Biodiesel; Breeding; CYP78A5; Jatropha.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000100003

Genetic diversity in two Italian almond collections
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rigoldi,Maria Pia; Rapposelli,Emma; De Giorgio,Donato; Resta,Paolo; Porceddu,Andrea.
Background Sweet-seeded domesticated almonds were brought to the Mediterranean Basin from central Asia about 4000 years ago. In Italy, most of the almonds produced are cultivated in the southern part of the country. Local populations of the tree in Sardinia are largely seed-derived and mostly self-incompatible, so have developed extensive genetic diversity. The need to protect biodiversity has prompted a revived interest in local genetic materials in almond. Two Italian collections have been established, one in Sardinia and the other in Apulia. These collections were the focus of the present evaluation of genetic diversity. Results Eleven SSRs (microsatellites) were used for fingerprinting. The Sardinian germplasm was highly polymorphic, revealing a mean...
Tipo: Journal article
Palavras-chave: Biodiversity; Genetic structure; Prunus amygdalus; SSR.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100008

Wild ornamental germplasm exploration and domestication based on biotechnological approaches: In vitro colchicine treatment to obtain a new cultivar of Scoparia montevidiensis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Escandón,Alejandro S; Miyajima,Ikuo; Alderete,Marisol; Hagiwara,Juan Carlos; Facciuto,Gabriela; Mata,Diego; Soto,Silvina M.
The genus Scoparia is native from Argentina. The diversity of colours and shape of their flowers bestows this genus a very interesting ornamental potential. The purpose of the present study is to explore the Scoparia species germplasm by means of in vitro polyploidization in order to improve their ornamental qualities. Accessions of S. montevidiensis var. montevidiensis, S. montevidiensis var. glandulifera, S. nudicaulis, S. hasleriana and S. dulcis were collected and maintained under greenhouse conditions. The Murashige-Skoog medium, supplemented with 0.25 mg/L BAP was used for the nodal segments multiplication of the five Scoparia species. Except for S. hasleriana, the multiplication rate of the other species ranged between 10 and 12 shoots per explant....
Tipo: Journal article
Palavras-chave: Chimera; Flow cytometry; Micropropagation; Ornamental plants; Tetraploid.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200010

Estimation of phylogenetic relationships of Phlomis species based on seed protein polymorphism
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yüzbasioglu,Ertugrul; Dadandi,Mehmet Yasar; Özcan,Servet.
In this study, phylogenetic relationships among 39 Phlomis taxa were investigated based on seed protein profiles produced by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). A total of 21 polypeptide bands were scored, of which, 19 were polymorphic among the taxa of the genus Phlomis. A distance matrix was generated from the similarity matrix which was computed by using Jaccard&amp;#8217;s similarity coefficients, based on polymorphic bands and then an UPGMA tree was established through cluster analysis performed on the distance matrix. Genetic distances ranged from 0.00 to 0.50 within subsection Dendrophlomis; from 0.00 to 0.625 within subsection Gymnophlomis and from 0.00 to 0.769 within subsection Oxyphlomis. The UPGMA tree formed...
Tipo: Journal article
Palavras-chave: Phlomis; Phlomoides; Phlomis taxa; SDS-PAGE; Seed proteins.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200002

Trametes versicolor growth and laccase induction with by-products of pulp and paper industry
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rebelo Barreto Xavier,Ana Maria; Mora Tavares,Ana Paula; Ferreira,Rita; Amado,Francisco.
The cultivation of Trametes versicolor for laccase production and cell growth were strongly dependent on experimental conditions namely physical and chemical parameters as well as nutrient availability and inducer stimulation. Biomass growth was compared for a rich medium and for a defined medium in two different temperatures. The best temperature was 28ºC and the maximum specific growth rates were µmax = 0.083 h-1 for the rich medium and µmax = 0.043 h-1 for the defined medium. It was clearly shown that laccase production is not associated with cell growth, indicating that this ligninolytic enzyme must be produced in the defined medium by a secondary metabolism. In order to obtain laccase induction, addition of solid lignin, lignosulphonates, veratryl...
Tipo: Journal article
Palavras-chave: Inducers; Laccase; Pulp and paper by-products; Trametes versicolor.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300012

Agrobacterium-mediated transient transformation of Mexican prickly poppy (Argemone mexicana L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Godoy-Hernández,Gregorio; Avilés-Berzunza,Elidé; Carrillo-Pech,Mildred; Vázquez-Flota,Felipe.
Shoot apex, leaf primordia, leaf sections and roots from Mexican prickly poppy seedlings, were inoculated with Agrobacterium tumefaciens harboring the binary vector pCAMBIA2301, which contained the &amp;beta;-glucuronidase (uid A) gene. Histochemical &amp;beta;-glucuronidase (GUS) assay in infected explants showed transient gus gene expression between 3 and 12 days after inoculation. To our knowledge, this is the first report of A. mexicana susceptibility to A. tumefaciens-mediated genetic transformation
Tipo: Journal article
Palavras-chave: Argemone mexicana &amp;beta; -glucuronidase benzylisoquinoline alkaloids genetic transformation neomycin phosphotransferase II.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100013

Management of the appropriate agricultural biotechnology for small producers: Bolivia case study
Provedor de dados: Electronic Journal of Biotechnology
Autores: Avila,Teresa; Izquierdo,Juan.
The Bolivia study is part of an ongoing multiple case study organized by the FAO's Regional Office for Latin America and the Caribbean as part of the activities of the Technical Cooperation Network on Agricultural Biotechnology (REDBIO/FAO). The basic information was obtained through a survey and/or direct interview to a significant number of experts from Bolivian institutions involving management, regulation, research, innovation, application and education of agricultural biotechnology. At national level, the most relevant applied agri-biotechnologies are presently in vitro plant culture, genomics, molecular genetics, assisted reproduction techniques in animals, and techniques supporting plant and animal disease diagnosis. They have been developed and...
Tipo: Journal article
Palavras-chave: Andean crops; Appropriate biotechnology; Biotechnology administration; Bolivia; Genetic resources; Policy; REDBIO/FAO; Regulations; Technical cooperation network on plant biotechnology.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100002

Characterization of residual oils for biodiesel production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Canesin,Edmilson Antonio; de Oliveira,Cláudio Celestino; Matsushita,Makoto; Felicidade Dias,Lucia; Reghiany Pedrão,Mayka; Evelazio de Souza,Nilson.
Background: Residual oils were characterized according to their physicochemical properties, i.e. acidity, iodine value, peroxide value and saponification number, to evaluate the degradation level and viability for biodiesel production. Results: The methyl esters of fatty acids (FAME) from samples of residual bovine, chicken and soybean oils were quantified by using four transesterification methods, using acidic and basic catalysis and, gas chromatography with flame ionization detector (GC-FID). Methods that used acidic catalysis at a lower temperature were the most efficient. Methyl biodiesel samples were synthesized by basic catalysis (KOH) for all quantified oils and the physicochemical properties of the biofuel were evaluated, i.e. viscosity, flash and...
Tipo: Journal article
Palavras-chave: Biodiesel properties; Gas chromatography; Infrared; Transesterification methods.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100007

Why are most Europeans opposed to GMOs?: Factors explaining rejection in France and Europe
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bonny,Sylvie.
A strong movement of opposition to GMOs developed in the late 1990s in many countries, especially in Europe, although these technologies were presented from the outset as highly promising and their advantages were often highlighted. How can this rejection be explained? The aim of this paper is to answer that question through the case of France, which is fairly representative in this respect of various European countries, even if the opposition movement is here particularly strong. One examines various factors, actors and processes that have led to such strong opposition to GMOs that at this stage their development in Europe has almost totally been halted. In the first part of the article we recall the results of several recent surveys, showing the level of...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000100008

Isolation of functional total RNA from Argemone mexicana tissues
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rubio-Piña,Jorge A; Vázquez-Flota,Felipe A.
RNA extraction from recalcitrant plant tissues is frequently complicated by the presence of secondary metabolites, polysaccharides and polyphenols. These compounds may co precipitate with RNA, often rendering it unsuitable for either cDNA synthesis or hybridization in northern blot analyses and therefore, interfering with the gene analysis expression in such tissues. We have developed an efficient RNA extraction method from A. mexicana tissues. The procedure includes the use of polyvinylpolypyrrolidone (PVPP), to remove secondary metabolites, proteins and polyphenols, and a two-step precipitation with LiCl, to eliminate polysaccharides, and thus increasing RNA yield. The quality of the resulting RNA was evaluated spectrophotometrically and by agarose gel...
Tipo: Journal article
Palavras-chave: Argemone mexicana; Plant tissues; RNA isolation; Secondary metabolites.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400015

Selection of reference genes for normalization of quantitative real-time PCR in cell cultures of Cyclamen persicum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hoenemann,Claudia; Hohe,Annette.
As a prerequisite for gene expression analyses in cell cultures of the ornamental crop Cyclamen persicum basic parameters for quantitative real-time polymerase chain reaction (qRT-PCR) have been established including the selection of reference genes using the software tools &amp;#8216;geNorm&amp;#8217; and &amp;#8216;NormFinder&amp;#8217;. Five potential reference genes have been tested (elongation factor tu (Ef-Tu), putative ABC transporter ATPase, putative conserved oligomeric Golgi (COG) complex component, V-ATPase G subunit 1 and Histone H3-K9 methyltransferase 4 (H3-K9-HMTase 4)). &amp;#8216;NormFinder&amp;#8217; as well as &amp;#8216;geNorm&amp;#8217; identified Ef-Tu to be the least stable reference gene while the ranking of the most stable genes...
Tipo: Journal article
Palavras-chave: Gene expression analysis; In vitro propagation; Primer design; Somatic embryogenesis.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100012

Biodegradation of agroindustrial wastes by Pleurotus spp for its use as ruminant feed
Provedor de dados: Electronic Journal of Biotechnology
Autores: Alborés,Silvana; Pianzzola,María Julia; Soubes,Matilde; Cerdeiras,María Pía.
The increasing expansion of agro-industrial activity has led to the accumulation of a large quantity of lignocellulosic residues all over the world. In particular, large quantities of rice straw (300.000 t) and citric bagasse (50.000 t) are annually produced in Uruguay. In this work we present the study of the bioconversion of these substrates with the edible mushroom Pleurotus spp so as to increase nutritional values and digestibility for its use as animal feed. The SSF process was optimized and the products after different periods of mushroom growth were evaluated. The microbial counts (cfu/g) for the inoculated substrates 44 days after incubation were 15 x 10(4), &lt; 10 and &lt; 10 for aerobic microorganisms, coliforms and E. coli, respectively. After...
Tipo: Journal article
Palavras-chave: Agroindustry; Basidiomycetes; Ruminant feed.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300008

The whole-cell immobilization of D-hydantoinase-engineered Escherichia coli for D-CpHPG biosynthesis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jin,Yuan-yuan; Li,Ya-dong; Sun,Wan; Fan,Shuai; Feng,Xiao-zhou; Wang,Kang-you; He,Wei-qing; Yang,Zhao-yong.
Background: D-Hydroxyphenylglycine is considered to be an important chiral molecular building-block of antibiotic reagents such as pesticides, and &amp;#946;-lactam antibiotics. The process of its production is catalyzed by D-hydantoinase and D-carbamoylase in a two-step enzyme reaction. How to enhance the catalytic potential of the two enzymes is valuable for industrial application. In this investigation, an Escherichia coli strain genetically engineered with D-hydantoinase was immobilized by calcium alginate with certain adjuncts to evaluate the optimal condition for the biosynthesis of D-carbamoyl-p-hydroxyphenylglycine (D-CpHPG), the compound further be converted to D-hydroxyphenylglycine (D-HPG) by carbamoylase. Results: The optimal medium to produce...
Tipo: Journal article
Palavras-chave: Calcium alginate; D-Carbamoyl-p-hydroxyphenylglycine; D-Hydantoinase; D-Hydroxyphenylglycine; Immobilization; Whole cell.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300004

Analysis of genetic diversity among Indian niger [Guizotia abyssinica (L. f.) Cass.] cultivars based on randomly amplified polymorphic DNA markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Nagella,Praveen; Hosakatte,Niranjana Murthy; Ravishankar,K.V.; Hahn,Eun-Joo; Paek,Kee-Yoeup.
Randomly amplified polymorphic DNA (RAPD) markers were used to estimate genetic diversity among 18 cultivars of niger from India. Total genomic DNA was extracted and subjected to RAPD analysis using 80 arbitrary 10-mer primers; 17 primers were selected, which yielded a total of 124 bands, 41.20% of them polymorphic. None of the primers produced unique banding pattern for each cultivar. RAPD data were used to calculate a Squared-Euclidean Distance matrix which revealed a minimum genetic distance between cultivars JNC-6 and N-48 and a maximum distance between IGP-76 and JN-30. Based on the distance matrix, a cluster analysis was done using a minimum variance algorithm. The dendrogram generated, based on Ward&amp;#8217;s method, grouped 18 niger cultivars...
Tipo: Journal article
Palavras-chave: Genetic diversity; Guizotia abyssinica; Molecular markers; RAPD.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100014

Construction of recombinant Bacillus subtilis strains for efficient pimelic acid synthesis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Wei-Wei; Yang,Ming-Ming; Li,Heng-xin; Wang,Dun.
As a precursor, pimelic acid plays an important role in biotin biosynthesis pathway of Bacillus subtilis. Fermentations supplemented with pimelic acid could improve the production of biotin, however, with a disadvantage-high cost. So it is necessary to improve the biosynthesis of pimelic acid via genetic engineering in B. subtilis. In this study, we constructed a recombinant B. subtilis strain for improving the synthesis of pimelic acid, in which a maltose-inducible Pglv promoter was inserted into the upstream of the cistron bioI-orf2-orf3 and, meanwhile, flanked by the tandem cistrons via a single crossover event. The copy number of the integrant was amplified by high-concentration resistance screen and increased to 4-5 copies. The production of pimelic...
Tipo: Journal article
Palavras-chave: Bacillus subtilis; Biosynthesis; Integration; Pglv promoter; Pimelic acid; Single crossover event.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600001

Analysis of the molecular basis of Xanthomonas axonopodis pv. citri pathogenesis in Citrus limon
Provedor de dados: Electronic Journal of Biotechnology
Autores: Siciliano,Florencia; Torres,Pablo; Sendín,Lorena; Bermejo,Carolina; Filippone,Paula; Vellice,Gabriel; Ramallo,Jackie; Castagnaro,Atilio; Vojnov,Adrian; Marano,María Rosa.
Xanthomonas axonopodis pathovar citri (Xac) causes bacterial citrus canker, a serious disease of most citrus species. Xanthomonas campestris pv. campestris (Xcc) is the causal agent of black rot disease in cruciferous plants. In Xcc, cell-cell signaling is mediated by diffusible signal factor (DSF). Synthesis of DSF depends on RpfB and RpfF. DSF perception and signal transduction have been suggested to involve a two-component system comprising RpfC and RpfG. It has been proposed that these proteins participate in a signal transduction system linking changes in the environment to the synthesis of DSF and the expression of virulence genes. Although the cluster of the rpf genes in Xac has synteny with the corresponding cluster in Xcc, two genes (rpfH and...
Tipo: Journal article
Palavras-chave: Canker; DSF; Extracellular polysaccharide; Quorum sensing.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300005

Immortalized human keratinocytes: A model system to study the efficacy of therapeutic drugs in response to the chemical warfare agent sulfur mustard (HD)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vazquez,Raymond; Nelson,Marian R; Guzman,Juanita J; Corun,Charlene M; Steinberg,Mark.
Cytokines have been established as biomarkers to detect exposure of cells to chemical warfare agents such as sulfur mustard (2,2'-dichlorodiethyl sulfide, HD). In this study cultured normal and SV40 immortalized human epidermal keratinocyte (NHEK/IHEK) cells were compared as potential model systems to measure the efficacy of therapeutic drugs against HD. Immortalized human epidermal keratinocytes resemble their primary cell counterparts but have the advantage of being carried through long-term culture. Immortalized cells also provide consistency and durability and are less costly than primary keratinocytes. Immunoassay studies were performed to examine the response of these two cell lines to HD. We found that both normal and immortalized NHEKs secreted the...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200006

Wheat biotechnology: A minireview
Provedor de dados: Electronic Journal of Biotechnology
Autores: Patnaik,Debasis; Khurana,Paramjit.
Due to the inherent difficulties associated with gene delivery into regenerable explants and recovery of plantlets with the introduced transgene, wheat was the last among cereals to be genetically transformed. This review attempts to summarize different efforts in the direction of achieving genetic transformation of wheat by various methods. Particle bombardment is the most widely employed procedure for the introduction of marker genes and also for the generation of transformed wheat with introduction of agronomically important genes for quality improvement, engineering of nuclear male sterility, transposon tagging, resistance to drought stress, resistance against fungal pathogens and insect resistance. The other methods of choice of gene delivery into...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200007

Comment on &amp;#8220;Equilibrium sorption isotherm studies of Cd(II), Pb(II) and Zn (II) ions detoxification from waste water using unmodified and EDTA-modified maize husk&amp;#8221;
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cavas,Levent.
The citing and using of correct version of mathematical equations are of great importance in the writing of a scientific paper. This paper presents the possible errors related to Dubinin-Radushkevich Equation in an article by Igwe and Abia (2007) which was published in Electronic Journal of Biotechnology, 10(4); 536-548.
Tipo: Journal article
Palavras-chave: Adsorption; Calculation errors; DR equation.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200001

Effects of temperature on the sorption of Pb2+ and Cd2+ from aqueous solution by Caladium bicolor (Wild Cocoyam) biomass
Provedor de dados: Electronic Journal of Biotechnology
Autores: Horsfall Jnr,Michael; Spiff,Ayebaemi I.
This report is based on the investigation of the effect of temperature on the removal of Pb2+ and Cd2+ in aqueous effluent using C. bicolor biomass in a batch sorption process. The result showed that the most suitable sorption temperature was 40ºC with maximum sorption capacities of 49.02 mg/g and 52.63 mg/g for Pb2+ and Cd2+ respectively. Various thermodynamic parameters, such as &amp;#916;Gº, &amp;#916;Hº, &amp;#916;Sº and Ea have been calculated. The data showed that the sorption process is spontaneous and exothermic in nature and that lower solution temperatures favours metal ion removal by the biomass. The findings of this investigation suggest that physical sorption plays a role in controlling the sorption rate. The sticking probability model was...
Tipo: Journal article
Palavras-chave: Biosorption; Cocoyam; Heavy metals removal; Temperature; Thermodynamics of sorption; Waste management.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200005

PCR-based sensitive detection of the edible fungus Boletus edulis from rDNA ITS sequences
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lian,Bin; Zang,Jin-ping; Hou,Wei-guo; Yuan,Sheng; Smith,Donald L.
Identification of commercially important fungi, such as the valuable edible fungus Boletus edulis can be difficult considering visual or metabolic approaches. Based on phylogenetic analysis of the rDNA ITS sequence, a pair of specific primers was designed for differentiating B. edulis from other mushrooms by PCR. PCR was performed with total DNA as a template at an annealing temperature between 56-60ºC. Positive amplicons were obtained from B. edulis with all DNA templates from fruit bodies and cultured mycelium, but not from other fungal species at an annealing temperature of 60ºC. The result indicated that B. edulis could be clearly distinguished from other fungi by PCR, and there were no misidentifications under the reaction conditions used. The primers...
Tipo: Journal article
Palavras-chave: Boletus edulis; Detection; Edible fungi; Internal transcribed spacer; PCR; Specific primers.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300011

Introduction of antifungal genes in sunflower via Agrobacterium
Provedor de dados: Electronic Journal of Biotechnology
Autores: Radonic,Laura Mabel; Zimmermann,Julián Marcos; Zavallo,Diego; López,Nilda; López Bilbao,Marisa.
There is evidence that overexpression of transgenes codifying antifungal proteins may confer protection to pathogen attack, and that this protection is increased due to the synergic effect of the expression of two or more genes. On the other hand it is well known that sunflower is a recalcitrant specie, highly difficult to be genetically transformed. In this context, the final aim of this project was to obtain sunflower plants expressing at least two antifungal genes, avoiding sequential transformation. The antifungal genes used encode for two enzymes that degrade the fungal wall (glucanase and chitinase), an osmotin and a ribosome inhibitor protein. Two types of transformation vectors were used: a more traditional system with a double cassette and a novel...
Tipo: Journal article
Palavras-chave: Antifungal genes; Double expression cassettes; Polyprotein cassettes; Sunflower; Transgenic plants.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000500008

Biochemical properties of an extracellular &amp;#946;-D-fructofuranosidase II produced by Aspergillus phoenicis under Solid-Sate Fermentation using soy bran as substrate
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rustiguel,Cynthia Barbosa; Oliveira,Arthur Henrique Cavalcanti de; Terenzi,Héctor Francisco; Jorge,João Atílio; Guimarães,Luis Henrique Souza.
The filamentous fungus A. phoenicis produced high levels of ?-D-fructofuranosidase (FFase) when grown for 72 hrs under Solid-State Fermentation (SSF), using soy bran moistened with tap water (1:0.5 w/v) as substrate/carbon source. Two isoforms (I and II) were obtained, and FFase II was purified 18-fold to apparent homogeneity with 14% recovery. The native molecular mass of the glycoprotein (12% of carbohydrate content) was 158.5 kDa with two subunits of 85 kDa estimated by SDS-PAGE. Optima of temperature and pH were 55Ã¯Â¿Â½C and 4.5. The enzyme was stable for more than 1 hr at 50Ã¯Â¿Â½C and was also stable in a pH range from 7.0 to 8.0. FFase II retained 80% of activity after storage at 4Ã¯Â¿Â½C by 200 hrs. Dichroism analysis showed the presence of random...
Tipo: Journal article
Palavras-chave: Agroindustrial substrate; Aspergillus; ?-D-fructofuranosidase; Solid state fermentation; Sucrose.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200002

Topological analysis of carbon flux during multi-stress adaptation in Halomonas sp. AAD12
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mangaoglu Yoruk,Hilal; Alpagu Sayar,Nihat.
Background Osmolytes with their effective stabilizing properties are accumulated as protectants not only against salinity but also against denaturing harsh environmental stresses such as freezing, drying, high temperatures, oxygen radicals and radiation. The present work seeks to understand how Halomonas sp. AAD12 cells redirect carbon flux specifically to replenish reactions for biomass and osmolyte synthesis under changing salinity and temperature. To accomplish this goal, a combined FBA-PCA approach has been utilized. Results Experimental data were collected to supply model constraints for FBA and for the verification of the model predictions, which were satisfactory. With restrictions on the various combinations of selected anaplerotic paths (reactions...
Tipo: Journal article
Palavras-chave: Flux balance analysis; Flux distribution; Halomonas sp. AAD12; Halophilic; Principle component analysis.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600015

Impact of simulated acid rain on soil microbial community function in Masson pine seedlings
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Lin; Chen,Zhan; Shang,He; Wang,Jing; Zhang,Peng-yan.
Background Accompanying its rapid economic development and population growth, China is the world's third largest acid rain region, following Europe and North America. The effects of acid rain on forest ecosystem were widely researched, including the growth, the nutrient of the leaf and soil, and so on. However, there are few reports about the effects of acid rain on the soil microbial diversity. This study investigated the effects of acid rain on soil microbial community function under potted Masson pine seedlings (Pinus massoniana Lamb). Results After 7 months of treatment with simulated acid rain, the low acid load treatment (pH 5.5) stimulated soil microbial activity, and increased soil microbial diversity and richness, while the higher levels of acid...
Tipo: Journal article
Palavras-chave: Biolog; Metabolic capability; Soil microbial activity; Soil microbial diversity and richness.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000500002

Biotechnology and Human Development in Developing Countries
Provedor de dados: Electronic Journal of Biotechnology
Autores: Doelle,Horst W.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300002

Analysis of Uruguayan weedy rice genetic diversity using AFLP molecular markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Federici,María Teresa; Vaughan,Duncan; Norihiko,Tomooka; Kaga,Akita; Xin,Wang Wang; Koji,Doi; Francis,Marta; Zorrilla,Gonzalo; Saldain,Nestor.
Weedy rice is a serious problem in Uruguayan rice fields since intensification of rice production started about 10 years ago. The genetic diversity of 26 weedy accessions of weedy rice and 6 Uruguayan cultivars were analyzed using AFLP (amplified fragment length polymorphisms) methodology. Abundant polymorphisms were found among samples tested. Using different methods of analysis three groups of samples were revealed. A relationship was found between three groups and morphological traits. One group had a black hull, purple apex and long awn (wild type traits) while another group had straw hull and apex, and short or no awn (domestication traits). The third group included the cultivars analyzed and some weedy rice samples. The weedy rice in this third group...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300008

Physiological, morphological, and mannanase production studies on Aspergillus niger uam-gs1 mutants
Provedor de dados: Electronic Journal of Biotechnology
Autores: De Nicolás-Santiago,Soledad; Regalado-González,Carlos; García-Almendárez,Blanca; Fernández,Francisco J; Téllez-Jurado,Alejandro; Huerta-Ochoa,Sergio.
Mutant strains from Aspergillus niger UAM-GS1 were produced by UV radiation to increase their hemicellulolytic and cellulolytic activity production. The mutant strains showing more enzymatic activity were those labelled GS1-S059 and GS1-S067. These strains also showed the largest relationship between diameter of hydrolysis zone and colony diameter. The mutant GS1-S067 showed a colony radial extension rate and a biomass growth rate g biomass/(cm² h), 1.17 times higher than that achieved by strain UAM-GS1. The high invasive capacity makes this mutant strain a promising alternative for its use in solid substrate fermentation (SSF). The morphological properties of the two mutant strains were evaluated by using scanning electron microscopy. The diameter of the...
Tipo: Journal article
Palavras-chave: Aspergillus niger; Mutation; Mannanase production.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100008

Protective effect of an antimicrobial peptide from Mytilus edulis chilensis expressed in Nicotiana tabacum L.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Arenas,Gloria; Marshall,Sergio H.; Espinoza,Valeria; Ramírez,Ingrid; Peña-Cortés,Hugo.
A "defensin-like" antibacterial peptide from Mytilus edulis chilensis, was sub-cloned into a binary vector for expression in plant tissues. The resulting new clone was electroporated into A. tumefaciens to transform tobacco plants. The presence of the construct in transgenic tobacco lines was demonstrated through RT-PCR, Northern and Western blots. Transformed positive plants were selected and grown for challenging. Tobacco leaves were infiltrated with Pseudomonassyringae pv. syringae and visual lesions determined at different times post-exposure. Of seven plants exposed, four gave variable protection up to seven days post-infection while one of them appears to be fully protected. These results suggest that defensin-like antimicrobial peptides from...
Tipo: Journal article
Palavras-chave: Antibacterial peptide; Disease resistance; In vivo expression; Nicotiana tabacum L.; Pseudomonassyringae pv. syringae; Transgenic tobacco plants.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200008

Genetic diversity analysis of traditional and improved cultivars of Pakistani rice (Oryza sativa L.) using RAPD markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rabbani,Malik Ashiq; Pervaiz,Zahida Hassan; Masood,Muhammad Shahid.
The molecular marker is a useful tool for assessing genetic variations and resolving cultivar identities. Information on genetic diversity and relationships among rice genotypes from Pakistan is currently very limited. The objective of this study was to evaluate the genetic polymorphisms and identities of 10 traditional, 28 improved and 2 Japanese cultivars of rice using the random amplified polymorphic DNA technique. Twenty-five decamer-primers could generate a total of 208 RAPD fragments, of which 186 or 89.4% were polymorphic. The number of amplification products produced by each primer varied from 4 to 16 with an average of 8.3 bands primer-1. The size of amplified fragments were ranged from 200 to 4000 bp. Pair-wise Nei and Li's similarity had...
Tipo: Journal article
Palavras-chave: Cultivar discrimination; Genetic variability; Oryza sativa; Pakistani rice; RAPDs.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300006

Characterization of cellulolytic activities of Bjerkandera adusta and Pycnoporus sanguineus on solid wheat straw medium
Provedor de dados: Electronic Journal of Biotechnology
Autores: Quiroz-Castañeda,Rosa E; Balcázar-López,Edgar; Dantán-González,Edgar; Martinez,Alfredo; Folch-Mallol,Jorge; Martínez Anaya,Claudia.
Cellulolytic properties of two white rot fungi, Bjerkandera adusta and Pycnoporus sanguineus, cultivated on wheat straw agar medium, were characterized and compared. Optimal growing parameters for maximum enzyme production for both fungi were wheat straw medium pH 5 and 28ºC. B. adusta showed, on the 6th day of culture, carboxymethylcellulose (CMC)ase activity levels 1.6 times higher than maximal P. sanguineus activity, achieved on the 8th day. B. adusta supernatants also displayed higher activity levels towards xylan (3.6-fold) compared to those of P. sanguineus. However, enzymes from P. sanguineus were more robust resisting one hour incubation at high temperatures (up to 80ºC), and exhibiting activity and stability in pH range from 2 to 8. Cellulolytic...
Tipo: Journal article
Palavras-chave: B. adusta; Cellulases; P. sanguineus; Wheat straw; Xylanases.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400005

Art, biotechnology and the culture of peace
Provedor de dados: Electronic Journal of Biotechnology
Autores: DaSilva,Edgar.
Biotechnology, in its voyage from ancient times into the expanding frontier areas of today's world of scientific research, has revealed itself as the gene of diplomacy and international cooperation in the relationships between nations (&lt;a href="#16"&gt;DaSilva, 2002&lt;/a&gt;). Economic and biotechnological considerations, strong elements in themselves, drive policy implementation that draws upon the support and sustenance of the public's logic and understanding of science obtained through the avenues of art and culture. More and more scientists are teaming up with artists to harness the world of microbes and biotechnology in the pursuit of one's natural well-being, of the conservation of environmental heritage, and of human comradeship and welfare. Art...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200007

PCR-based DGGE and FISH analysis of methanogens in an anaerobic closed digester tank for treating palm oil mill effluent
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tabatabaei,Meisam; Zakaria,Mohd Rafein; Rahim,Raha Abdul; Wright,André-Denis G.; Shirai,Yoshihito; Abdullah,Norhani; Sakai,Kenji; Ikeno,Shinya; Mori,Masatsugu; Kazunori,Nakamura; Sulaiman,Alawi; Hassan,Mohd Ali.
16S ribosomal RNA (rRNA)-targeted fluorescent in situ hybridization combined with polymerase chain reaction (PCR)-cloning, light microscopy using Gram stains, scanning electron microscopy and denatured gradient gel electrophoresis were used to reveal the distribution of methanogens within an anaerobic closed digester tank fed with palm oil mill effluent. For specific detection of methanogens, 16S rRNA-cloning analysis was conducted followed by restriction fragment length polymorphism (RFLP) for presumptive identification of methanogens. To cover the drawbacks of the PCR-cloning study, the organization of the microorganisms was visualized in the activated sludge sample by using fluorescent oligonucleotide probes specific to several different methanogens,...
Tipo: Journal article
Palavras-chave: Anaerobic digestion; DGGE; FISH; Methanogens; POME.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300012

Assessment of molecular recognition element for the quantification of human epidermal growth factor using surface plasmon resonance
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rosti,Ira Amira; Ramanan,Ramakrishnan Nagasundara; Ling,Tau Chuan; Ariff,Arbakariya B.
Background: A method for the selection of suitable molecular recognition element (MRE) for the quantification of human epidermal growth factor (hEGF) using surface plasmon resonance (SPR) is presented. Two types of hEGF antibody, monoclonal and polyclonal, were immobilized on the surface of chip and validated for its characteristics and performance in the quantification of hEGF. Validation of this analytical procedure was to demonstrate the stability and suitability of antibody for the quantification of target protein. Results: Specificity, accuracy and precision for all samples were within acceptable limit for both antibodies. The affinity and kinetic constant of antibodies-hEGF binding were evaluated using a 1:1 Langmuir interaction model. The model...
Tipo: Journal article
Palavras-chave: Antibody; BIAcore; Biosensors; Epidermal growth factor; Validation.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600015

Novel antimicrobial activity of a dichloromethane extract obtained from red seaweed Ceramium rubrum (Hudson) (Rhodophyta: Florideophyceae) against Yersinia ruckeri and Saprolegnia parasitica, agents that cause diseases in salmonids
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cortés,Yurima; Hormazábal,Emilio; Leal,Hellmuth; Urzúa,Alejandro; Mutis,Ana; Parra,Leonardo; Quiroz,Andrés.
Background Enteric red mouth disease and Saprolegniasis, which are caused by the bacteria Yersinia ruckeri and the oomycete Saprolegnia parasitica, respectively, are important illnesses that affect salmonid farming. Sanitary problems in farms are addressed by the prevention of disease outbreaks or by the treatment of diseases with chemicals. Environmental and governmental restrictions, toxicity and high treatment costs limit the use of drugs. Marine organisms, such as algae, sponges and corals, have developed an antimicrobial defense strategy based on the production of bioactive metabolites. Among these organisms, seaweeds offer a particularly rich source of potential new drugs. Hence, many pharmacologically active substances have been isolated from...
Tipo: Journal article
Palavras-chave: Antimicrobial activity; Bacteria; Fish pathogens; Lipophilic extract.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000300004

Identification of chilling-responsive transcripts in peanut (Arachis hypogaea L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tang,Yue Yi; Wang,Chuan Tang; Yang,Guan Pin; Feng,Tong; Gao,Hua Yuan; Wang,Xiu Zhen; Chi,Xiao Yuan; Xu,Ya Long; Wu,Qi; Chen,Dian Xu.
To isolate differentially expressed peanut genes responsive to chilling, a suppression subtractive hybridization (SSH) cDNA library was constructed for a chilling tolerant peanut cultivar A4 with mRNAs extracted from the seeds imbibed at 2ºC and 15ºC, respectively, for 24 hrs. A total of 466 cDNA clones were sequenced, from which 193 unique transcripts (73 contigs and 120 singlets) were assembled. Of these unique transcripts, 132 (68.4%) were significantly similar to the sequences in GenBank non-redundant (nr) protein database, which belonged to diverse functional categories including metabolism, signal transduction, stress response, cell defense and transcriptional regulation. The remaining 61 (31.6%) showed no similarity to either hypothetical or known...
Tipo: Journal article
Palavras-chave: Chilling response; Peanut; Real-time quantitative PCR; Suppression subtractive hybridization.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500005

Ranking agro-technical methods and environmental parameters in the biodegradation of petroleum-contaminated soils in Nigeria
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kogbara,Reginald B.
A combination of experimental cells consisting of some agro-technical methods aimed at accelerating the biodegradation of petroleum contaminated soils were evaluated in order to ascertain the relevance of these methods and the relative attention due necessary soil environmental parameters. The methods of treatment involved the variation of tilling, watering and nutrient application, plus biopile and phytoremediation treatments. In the experiments described, petroleum contamination of soils was simulated under field conditions, the remedial treatments were then utilized for clean up. Analysis of soil parameters after a six-week study period showed an increase in total heterotrophic bacteria (THB) counts across all the treatments, with THB counts increasing...
Tipo: Journal article
Palavras-chave: Bioremediation methods; Performance index; Phytoremediation; Total hydrocarbon content.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100011

Biotechnology Issues for Developing Economies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Johnson,D. Gale.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100002

Production, purification and characterization of recombinant human antithrombin III by Saccharomyces cerevisiae
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mallu,Maheswara Reddy; Vemula,Sandeep; Ronda,Srinivasa Reddy.
Background: Antithrombin III (ATIII) is a protein that inhibits abnormal blood clots (or coagulation) by breaking down thrombin and factor Xa. ATIII helps to keep a healthy balance between hemorrhage and coagulation. The present work demonstrated the production, purification and characterization of recombinant human antithrombin (rhAT) from yeast Saccharomyces cerevisiae BY4741 was demonstrated. After expression of rhAT by S. cerevisiae, the biomass and rhAT concentration were analyzed through fed-batch fermentation process. Results: In fed-batch fermentation, the biomass (maximum cell dry weight of 11.2 g/L) and rhAT concentration (312 mg/L) of the expressed rhAT were achieved at 84 h of cultivation time. The maximum cell lysis efficiency (99.89%) was...
Tipo: Journal article
Palavras-chave: Biological activity; Cell lysis; Cross flow filtration; Fed-batch fermentation; Purification; Secondary structure.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400012

Continuous gluconic acid production by Aureobasidium pullulans with and without biomass retention
Provedor de dados: Electronic Journal of Biotechnology
Autores: Anastassiadis,Savas; Rehm,Hans-Jürgen.
New alternative processes for the continuous production of gluconic acid by Aureobasidium pullulans, using biomass retention by cell immobilization or cross over filtration, are described in the present work. 315 g/l gluconic acid was continuously produced in chemostat cultures at 21 hrs residence time without any biomass retention. 260 g/l gluconic acid was produced in fluidized bed reactor at 21 hrs residence time. The support carrier was overgrown resulting in limitations of oxygen transfer towards the inner layers of immobilized biomass. 375 g/l gluconic acid was produced under continuous cultivation at 22 hrs of residence time with a formation rate for the generic product of 17 g/(l x h) and a specific gluconic acid productivity of only 0.74 g/(g x...
Tipo: Journal article
Palavras-chave: Biomass immobilization; Continuous fermentation; Cross over filtration; Gluconic acid fermentation; Reaction technique; Residence time.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500004

Occurrence of the rust resistance gene Lr37 from Aegilops ventricosa in Argentine cultivars of wheat
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bulos,Mariano; Echarte,Mariel; Sala,Carlos.
Leaf rust of wheat (Triticum aestivum L.) caused by the fungus Puccinia triticina (formerly P. recondita f. sp. tritici), is one of the most important foliar diseases of this crop. Lr37 rust resistance gene, which confers resistance in wheat against leaf rust, was introgressed into cultivated wheat from Aegilops ventricosa Tausch. Rust races with virulence to Lr37 have been identified in different countries, but it still provides resistance to a wide range of races and is useful in combination with other resistance genes. There are no reports about the presence, frequency and origin of Lr37 in Argentinean wheat cultivars. In this work, we analyzed 88 registered Argentinean wheat cultivars developed by different breeding companies and institutions during...
Tipo: Journal article
Palavras-chave: Diversity; Marker assisted selection; Puccinia triticina; Triticum aestivum; Translocation.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500014

The molecular characterization of a cyclophilin A from Chinese mitten crab Eriocheir sinensis and the antifungal activity of its recombinant protein
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Mengqiang; Zhang,Daoxiang; Wang,Lingling; Gai,Yunchao; Zhou,Zhi; Zhang,Huan; Song,Linsheng.
Background: Cyclophilin A (CypA), a receptor for the immunosuppressive agent cyclosporin A (CsA), is a cis-trans peptidyl-prolyl isomerase (PPIase) which accelerates the cis-trans isomerization of prolyl-peptide bonds and interacts with a variety of proteins to regulate their activities. Results: The full-length cDNA of crab Eriocheir sinensis CypA (EsCypA) was cloned by EST and RACE technique. The complete sequence of EsCypA cDNA contained a 5' untranslated region (UTR) of 50 bp, a 3&amp;#146; UTR of 233 bp with a polyA tail, and an open reading frame (ORF) of 495 bp encoding a polypeptide of 164 amino acids with the predicted molecular weight of 17.36 kDa. The deduced amino acid sequence of EsCypA contained two highly conserved signature sequences of...
Tipo: Journal article
Palavras-chave: Antifungal activity; Cyclophilin A; Eriocheir sinensis; Immune response; PPIase activity.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000200002

Evaluation of computer methods for biomarker discovery on computational grids
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tonini,Gustavo; Siqueira,Frank.
Background: Discovering biomarkers is a fundamental step to understand and deal with genetic diseases. Methods using classic Computer Science algorithms have been adapted in order to support processing large biological data sets, aiming to find useful information to understand causing conditions of diseases such as cancer. Results: This paper describes some promising biomarker discovery methods based on several grid architectures. Each technique has some features that make it more suitable for a particular grid architecture. This matching depends on the parallelizing capabilities of the method and the resource availability in each processing/storage node. Conclusion: The study described in this paper analyzed the performance of biomarker discovery methods...
Tipo: Journal article
Palavras-chave: Feature selection; Genetics; Parallel computing; Pattern detection; Performance.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500013

Investigation of cultivation conditions for capsular polysaccharide production by Streptococcus pneumoniae serotype 14
Provedor de dados: Electronic Journal of Biotechnology
Autores: Moura Leal,Maria de Lourdes; da Silva Gomes Pereira,Denise; Jessouroun,Ellen; Peixoto Gimenes Couto,Maria Antonieta; Pereira Jr,Nei.
Streptococcus pneumoniae (pneumococcus) is among the most significant causes of bacterial disease in humans. Capsular polysaccharide (CPS) production is essential for pneumococcal virulence. Pneumococcal CPS has been widely used as vaccine antigen. This study is focused on the influence of culture conditions of Streptococcus pneumoniae serotype 14 as for developing an industrial method for polysaccharide production. The pH proved to be a highly important variable in batchwise culture. Using the pH control all glucose added was consumed resulting in a four-fold increase in polysaccharide productivity relative to cultivation without pH control. S. pneumoniae is a lactic acid bacterium, so named for its primary metabolic byproduct (lactate), which has an...
Tipo: Journal article
Palavras-chave: Polysaccharide capsular; Vaccine; Streptococcus pneumoniae.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500006

Construction of a molecular identification profile of new varieties of Nierembergia linariaefolia by anchored microsatellites
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pérez de la Torre,Mariana C.; Escandón,Alejandro S.
The objective of the present work was to establish the molecular identification profile for six new varieties of Nierembergia linariaefolia to incorporate the fingerprint, as complementary information to the standard registration data. Total DNA was extracted from young leaves following the protocol of the cetyltrimethylammonium bromide. Anchored microsatellites were used as molecular markers. The amplification reactions were carried out with seven primers. A total of 251 loci were detected, 98% of them were polymorphic. The average of polymorphic loci was 35 loci per primer and, 41 loci per genotype. Six out of the seven primers used discriminated all the individuals involved in the present study; consequently, it was possible to generate the molecular...
Tipo: Journal article
Palavras-chave: ISSR; Ornamentals; Varietal identification.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300014

Asn336 is involved in the substrate affinity of glycine oxidase from Bacillus cereus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wu,Gaobing; Zhan,Tao; Guo,Yiming; Kumar,Ashok; Liu,Ziduo.
Background: Glycine oxidase (GO), a type of D-amino acid oxidase, is of biotechnological interest for its potential in several fields. In our previous study, we have characterized a new glycine oxidase (BceGO) from Bacillus cereus HYC-7. Here, a variant of N336K with increased the affinity against all the tested substrate was obtained by screening a random mutant library of BceGO. It is observed that the residue N336 is invariable between its homogeneous enzymes. This work was aimed to explore the role of the residue N336 in glycine oxidase by site-directed mutagenesis, kinetic assay, structure modeling and substrate docking. Results: The results showed that the affinity of N336H, N336K and N336R increased gradually toward all the substrates, with increase...
Tipo: Journal article
Palavras-chave: Bacillus cereus; Error-prone PCR; Glycine oxidase; Site-directed mutagenesis; Substrate affinity.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400004

Overproduction of clavulanic acid by extractive fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lopes Costa,Cecília Ladeira; Colli Badino,Alberto.
Background Clavulanic acid is an important beta-lactamase inhibitor produced as a secondary metabolite by the actinomycete Streptomyces clavuligerus. Clavulanic acid is chemically unstable; therefore, it is degraded during bacterial cultivation. In this work, the adsorbents clinoptilolite, activated carbon, calcined hydrotalcite, and Amberlite IRA 400 anionic exchange resin were studied in terms of their ability to adsorb clavulanic acid during extractive fermentation, in order to prevent product degradation and avoid product concentrations reaching inhibitory levels. Adsorption assays were used to investigate the effect of pH, and the decrease in the clavulanic acid concentration in the culture broth was measured for each adsorbent. Results IRA 400 was...
Tipo: Journal article
Palavras-chave: Adsorption; Clavulanic acid; Extractive fermentation; Integrated processing; Product inhibition.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300003

Overexpression of the pineapple fruit bromelain gene (BAA) in transgenic Chinese cabbage (Brassica rapa) results in enhanced resistance to bacterial soft rot
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jung,Yu-Jin; Choi,Chang-Sun; Park,Jin-Heui; Kang,Hee-Wan; Choi,Je-Eul; Nou,Ill-Sup; Lee,Soon Youl; Kang,Kwon-Kyoo.
Bromelain is a crude protein extract obtained from pineapple stems, which comprises a variety of proteolytic enzymes. It exhibits potential therapeutic activities against trauma, inflammation, autoimmune diseases and malignant disorders. In this study, we cloned BAA1 (the gene encoding fruit bromelain) into a plant expression vector that was then used to transform Brassica rapa and overexpress BAA1 under the control of the cauliflower mosaic virus (CaMV) 35S promoter. We demonstrate that constitutive overexpression of BAA1 in B. rapa confers enhanced resistance to the soft rot pathogen Pectobacterium carotovorum ssp. carotovorum. These results suggest that it could be utilized for protecting plants from attack by bacterial pathogens
Tipo: Journal article
Palavras-chave: Brassica rapa; Fruit bromelain; Soft rot resistance; Transgenic plant.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100007

Biodegradation of a blended starch/natural rubber foam biopolymer and rubber gloves by Streptomyces coelicolor CH13
Provedor de dados: Electronic Journal of Biotechnology
Autores: Watcharakul,Sirimaporn; Umsakul,Kamontam; Hodgson,Brian; Chumeka,Wannapa; Tanrattanakul,Varaporn.
Background: The growing problem of environmental pollution caused by synthetic plastics has led to the search for alternative materials such as biodegradable plastics. Of the biopolymers presently under development, starch/natural rubber is one promising alternative. Several species of bacteria and fungi are capable of degrading natural rubber and many can degrade starch. Results: Streptomyces coelicolor CH13 was isolated from soil according to its ability to produce translucent halos on a mineral salts medium, MSM, supplemented with natural rubber and to degrade starch. Scanning electron microscope studies showed that it colonized the surfaces of strips of a new starch/natural rubber biopolymer and rubber gloves and caused degradation by forming holes,...
Tipo: Journal article
Palavras-chave: Biodegradation; Biopolymer; Natural rubber; Starch; Streptomyces coelicolor.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000100008

A most effective method for selecting a broad range of short and medium-chain-length polyhidroxyalcanoate producing microorganisms
Provedor de dados: Electronic Journal of Biotechnology
Autores: Revelo Romo,Dolly Margot; Grosso,María Victoria; Moreno Solano,Nubia Carmenza; Montoya Castaño,Dolly.
A molecular approach was used for selecting polyhydroxyalcanoate (PHA)-accumulating potential Gram-negative bacteria from different genera by colony polymerase chain reaction (PCR). Three degenerate primers were designed for amplifying a fragment from PHA synthase gene (phaC) (Class I), phaC1 and phaC2 (Class II) genes for detecting PHA-producing bacteria. Thirty-four out of 55 bacterial strains from the old collection selected using Sudan black B staining were phaC+. PCR was used for directly selecting 35 new collection bacterial strains; these strains were phaC+ and their ability to produce PHA was confirmed by Sudan black B staining. Four specific primers were designed on genes of Class II PHA biosynthesis operon. These primers were used for evaluating...
Tipo: Journal article
Palavras-chave: 16S rDNA; Colony PCR; Degenerate primers; PHA synthase; Polyhydroxyalcanoate; Seminested PCR.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300002

Effect of temperature and initial pH on biohydrogen production from palm oil mill effluent: long-term evaluation and microbial community analysis
Provedor de dados: Electronic Journal of Biotechnology
Autores: O-Thong,Sompong; Mamimin,Chonticha; Prasertsan,Poonsuk.
Anaerobic sludge from palm oil mill effluent (POME) treatment plant was used as a source of inocula for the conversion of POME into hydrogen. Optimization of temperature and initial pH for biohydrogen production from POME was investigated by response surface methodology. Temperature of 60ºC and initial pHof 5.5 was optimized for anaerobic microflora which gave a maximum hydrogen production of 4820 ml H2/l-POME corresponding to hydrogen yield of 243 ml H2/g-sugar. Total sugar consumption and chemical oxygen demand (COD) removal efficiency were 98.7% and 46%, respectively. Long-term hydrogen production in continuous reactor at HRT of 2 days, 1 day and 12 hrs were 4850 ± 90, 4660 ± 99 and 2590 ± 120 ml H2/l-POME, respectively. Phylogenetic analysis of the...
Tipo: Journal article
Palavras-chave: Biohydrogen; Long-term evaluation; Palm oil mill effluent; Response surface methodology; Thermophilic condition.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500009

Visualization of avian influenza virus infected cells using self-assembling fragments of green fluorescent protein
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kanehira,Katsushi; Uchida,Yuko; Saito,Takehiko.
Background: Avian influenza viruses (AIVs) are influenza A viruses which are isolated from domestic and wild birds. AIVs that include highly pathogenic avian influenza viruses (HPAIVs) are a major concern to the poultry industry because they cause outbreaks in poultry with extraordinarily high lethality. In addition, AIVs threaten human health by occasional zoonotic infection of humans from birds. Tools to visualize AIV-infected cells would facilitate the development of diagnostic tests and preventative methods to reduce the spread of AIVs. In this study, a self-assembling split-green fluorescent protein (split-GFP) system, combined with influenza virus reverse genetics was used to construct a visualization method for influenza virus-infected cells....
Tipo: Journal article
Palavras-chave: Avian influenza virus; Reverse genetics; Split-GFP.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000100010

Tilapia chromosomal growth hormone gene expression accelerates growth in transgenic zebrafish (Danio rerio)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Morales,Reynold; Herrera,María Teresa; Arenal,Amílcar; Cruz,Asterio; Hernández,Oscar; Pimentel,Rafael; Guillén,Isabel; Martínez,Rebeca; Estrada,Mario P.
Gene transfer is economically important and model fish species has produced a great impact in modern biology and biotechnology. Transgenic zebrafish (Danio rerio) were generated through the co-injection of a GFP-expressing plasmid and an "all fish" transgene composed by the carp beta-actin promoter and the chromosomal tilapia (Oreochromis hornorum) growth hormone gene. The GFP expression was a good indicator of stable transformation and allowed for high efficiency selection of transgenic fish. Transgenic F1 zebrafish grew 20% faster than full sibling non-transgenic controls.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200004

Modeling of glutamic acid production by Lactobacillus plantarum MNZ
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zareian,Mohsen; Ebrahimpour,Afshin; Mohamed,Abdul Karim Sabo; Saari,Nazamid.
Background: L-glutamic acid, the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism acts as a precursor of &amp;#947;-amino butyric acid (GABA). In the present study, culture condition for enhanced glutamic acid production by Lactobacillus plantarum MNZ was optimized and the influence of such conditions on GABA production was evaluated. Results: Results indicated that glutamic acid increased up to 3-fold (3.35) under the following condition: pH 4.5, temperature 37ºC, 12% (w/v) glucose and 0.7% (w/v) ammonium nitrate; whilst GABA production was enhanced up to 10-fold under the following condition: pH 4.5, temperature 37ºC, 6% (w/v) glucose and 0.7% (w/v) ammonium nitrate. Conclusions: This is the first report for...
Tipo: Journal article
Palavras-chave: &amp;#947; -amino butyric acid functional foods lactic acid bacteria medium optimization response surface methodology.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400012

Comparative study for the kinetics of extracellular xylanases from Trichoderma harzianum and Chaetomium thermophilum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ahmed,Sibtain; Imdad,Syeda Sana; Jamil,Amer.
Xylanases assume special importance in the paper and pulp industry as they replace toxic chemicals such as chlorine and chlorine dioxide for developing eco-friendly processes. This study evaluated xylanases produced by two fungi, the mesophilic fungus Trichoderma harzianum and a thermophilic fungus Chaetomium thermophilum. Among the polymeric substrates studied for xylanase production by both the fungi, birch wood xylan was found to be the best inducer of xylanases. Xylanases induction was subject to glucose repression. Partially purified xylanases preparation from T. harzianum and C. thermophilum exhibited optimal activities at pH 5 and 6 and at 60ºC and 70ºC, respectively. The apparent Km and Vmax values for the partially purified xylanase from T....
Tipo: Journal article
Palavras-chave: C. thermophilum; Kinetics; T. harzianum; Xylanase.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000300003

3-D modeling and molecular dynamics simulation of interleukin-22 from the So-iny mullet, Liza haematocheila
Provedor de dados: Electronic Journal of Biotechnology
Autores: Qi,Zhitao; Shi,Rongwei; Li,Suyang; Zang,Xiayan; Wang,Zisheng.
Background: Interleukin-22 (IL-22) plays an important role in the regulation of immune responses. However, little is known about its function or structure in fish. Results: The IL-22 gene was first cloned from So-iny mullet (Liza haematocheila), one of commercially important fish species in China. Then, 3-D structure model of the mullet IL-22 was constructed by comparative modeling method using human IL-22 (1M4R) as template, and a 5 ns molecular dynamics (MD) was studied. The open reading frame (ORF) of mullet IL-22 cDNA was 555 bp, encoding 184 amino acids. The mullet IL-22 shared higher identities with the other fish IL-22 homologs and possessed a conserved IL-10 signature motif at its C-terminal. The mullet IL-22 model possessed six conserved helix...
Tipo: Journal article
Palavras-chave: Comparative modeling; Interleukin-22; Liza haematocheila; Molecular dynamics.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400003

Production of an extracellular keratinase from Chryseobacterium sp. growing on raw feathers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Brandelli,Adriano; Riffel,Alessandro.
The strain Chryseobacterium sp. kr6 shown to be useful for biotechnological purposes such as hydrolysis of poultry feathers and de-hairing of bovine pelts. The effect of temperature, initial pH and media composition on protease production by this keratinolytic strain was studied. The enzyme was produced between 25 and 37ºC, with maximum activity and yield at 30ºC. When protease production was tested in media with different initial pH, maximum activity was observed when cultivation was carried out at 30ºC and initial pH ranging from 6.0 to 8.0. Higher activity was observed when feathers or feather meal were used as growth substrates, followed by soybean meal. The addition of carbohydrates or surfactants to feather broth resulted in decrease in keratinolytic...
Tipo: Journal article
Palavras-chave: Bacteria; Enzyme; Keratin; Protease.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100007

Construction and application of a built-in dual luciferase reporter for microRNA functional analysis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bi,Yanzhen; Zheng,Xinmin; Shao,Changwei; Pan,Wen; Jiang,Li; Ouyang,Huiwu.
Background: As key gene regulators, microRNAs post-transcriptionally modulate gene expression via binding to partially complementary sequence in the 3? UTR of target mRNA. An accurate, rapid and quantitative tool for sensing and validation of miRNA targets is of crucial significance to decipher the functional implications of miRNAs in cellular pathways. Results: Taking advantage of an improved restriction-free cloning method, we engineered a novel built-in dual luciferase reporter plasmid where Firefly and Renilla luciferase genes were assembled in a single plasmid named ?pFila?. This design eliminates the transfection of a separate control plasmid and thus minimizes the time and labor required for miRNA-target sensing assays. pFila consistently produces...
Tipo: Journal article
Palavras-chave: Biosensor; Luciferase; Ligase-independent; MiRNA; Target.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200011

Biotechnology and the developing world
Provedor de dados: Electronic Journal of Biotechnology
Autores: DaSilva,Edgar J.; Baydoun,Elias; Badran,Adnan.
The life sciences offer opportunities for revolutionizing human welfare activities. Enriched by inputs from genomic research, biotechnology is a major force for development in all countries. Entwined with culture and socio-ethical values, biotechnology contributes to solving problems like food and water insecurity that impede national development and threaten peace in the developing world. The lack of facilities and professional skills in biotechnology limits R &amp;amp; D initiatives in the developing and the least developed countries (LDCs); and, restricts their full participation in take-off activities in national and self-reliant regional ventures in sustainable development. The practice of biotechnology different in many developing countries is...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100013

Technology Exchange
Provedor de dados: Electronic Journal of Biotechnology
Autores: Douthwaite,Boru; Ortiz,Rodomiro.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200002

Isolation and characterization of drought-responsive genes from peanut roots by suppression subtractive hybridization
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ding,Hong; Zhang,Zhi Meng; Qin,Fei Fei; Dai,Liang Xiang; Li,Chun Juan; Ci,Dun Wei; Song,Wen Wu.
Background Peanut (Arachis hypogaea L.) is an important economic and oilseed crop. Long-term rainless conditions and seasonal droughts can limit peanut yields and were conducive to preharvest aflatoxin contamination. To elucidate the molecular mechanisms by which peanut responds and adapts to water limited conditions, we isolated and characterized several drought-induced genes from peanut roots using a suppression subtractive hybridization (SSH) technique. Results RNA was extracted from peanut roots subjected to a water stress treatment (45% field capacity) and from control plants (75% field capacity), and used to generate an SSH cDNA library. A total of 111 non-redundant sequences were obtained, with 80 unique transcripts showing homology to known genes...
Tipo: Journal article
Palavras-chave: Drought-related genes; Drought stress; GO and KEGG analyses; Real-time reverse transcription-PCR.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600008

Optimization of &amp;#946;-carotene production by a newly isolated Serratia marcescens strain
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Bohua; Lin,Liping; Lu,Lei; Chen,Weiping.
&amp;#946;-carotene is a commonly used food colorant. In this work, a novel &amp;#946;-carotene producing strain, Serratia marcescens RB3, was isolated and identified by physiological and biochemical tests, as well as 16S rDNA sequence analysis. The production of &amp;#946;-carotene by S. marcescens RB3 was identified through HPLC analysis. The cultivation conditions for &amp;#946;-carotene production by S. marcescens RB3 were optimized as 2.0% lactose, 2.0% peptone, 0.3% beef extract, 1.0% NaCl supplemented with 0.05% Fe2+, pH 6.0 and 30ºC. Under the optimal conditions, the yield of &amp;#946;-carotene achieved 2.45 µg/mL.
Tipo: Journal article
Palavras-chave: &amp;#946; -carotene optimization pigment Serratia marcescens.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600003

Characterization of the acetohydroxyacid synthase multigene family in the tetraploide plant Chenopodium quinoa
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mestanza,Camilo; Riegel,Ricardo; Silva,Herman; Vásquez,Santiago C.
Background Currently, the technology called Clearfield® is used in the development of crops resistant to herbicides that inhibit the enzyme acetohydroxy acid synthase (AHAS, EC 2.2.1.6). AHAS is the first enzyme of the biosynthetic pathway that produces the branched-chain of the essential amino acids valine, leucine, and isoleucine. Therefore, multiple copies of the AHAS gene might be of interest for breeding programs targeting herbicide resistance. In this work, the characterization of the AHAS gene was accomplished for the Chenopodium quinoa Regalona-Baer cultivar. Cloning, sequencing, and Southern blotting were conducted to determine the number of gene copies. Results The presence of multiple copies of the AHAS gene as has been shown previously in...
Tipo: Journal article
Palavras-chave: Acetohydroxyacid synthase; Acetolactate synthase; Chenopodium quinoa; Homeologous pairing; Gene duplication.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600002

A rapid method for an offline glycerol determination during microbial fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kuhn,Jennifer; Müller,Hagen; Salzig,Denise; Czermak,Peter.
Background The purpose of this work was to find a rapid method for glycerol detection during microbial fermentations. The method requirements were, first, to avoid sample pretreatment, and second, to measure glycerol precisely especially out of fermentation broth. Results This was achieved by combining two reaction principles - the Malaprade reaction and the Hantzsch reaction. In the Malaprade reaction, glycerol is converted into formaldehyde. This forms a dye in the Hantzsch reaction after which adsorption is than detected. The subsequent assay was investigated with two different fermentation media, a chemically undefined and a chemically defined media, used for Pichia pastoris fermentation. In both media, as well as in real fermentation samples, glycerol...
Tipo: Journal article
Palavras-chave: Glycerol determination; Fermentation broth; Hantzsch reaction; Malaprade reaction.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300017

Synthesis of silver nanoparticles using a biosurfactant produced in low-cost medium as stabilizing agent
Provedor de dados: Electronic Journal of Biotechnology
Autores: Farias,Charles B.B.; Ferreira Silva,Aline; Diniz Rufino,Raquel; Moura Luna,Juliana; Gomes Souza,José Edson; Sarubbo,Leonie Asfora.
Background A biosurfactant produced by Pseudomonas aeruginosa cultivated in a low-cost medium formulated with 2.5% vegetable oil refinery residue and 2.5% corn steep liquor and distilled water was employed to stabilize silver nanoparticles in the liquid phase. The particles were initially synthesized using NaBH4 as reducing agent in biosurfactant reverse micelles and were extracted from the micellar solution to disperse in heptane. Results A silver particle size in the range of 1.13 nm was observed. The UV-vis absorption spectra proposed that silver nanoparticles could be formed in the reverse micelles and relatively stabilized for at least 3 months without passivator addition. The Transmission Electron Microscope (TEM) shows that the silver nanoparticles...
Tipo: Journal article
Palavras-chave: Microbial surfactant; Nanoscale materials; Pseudomonas aeruginosa.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000300003

Natural selection in common bean microsatellite alleles and identification of QTLs for grain yield
Provedor de dados: Electronic Journal of Biotechnology
Autores: Leite,Monik Evelin; Santos,João Bosco dos; Carneiro,Flávia Fernandes; Couto,Karla Rodrigues.
Natural selection acts to select better adapted individuals or alleles in segregating population and help plant breeding. The objective of this work was to verify the effect of natural selection on microsatellite alleles as indicators of better adaptation and identification of quantitative trait loci (QTLs) for grain yield. This study evaluated 107 progenies from the F8 and 107 from the F24 generation derived from crossing Carioca MG and ESAL 686 lines, carried out by the bulk method, and evaluated in three different seasons: winter 2001; rainy 2001 and dry 2002. It was utilized 22 polymorphic markers and the natural selection acted in all of them. The frequency of the alleles of the parent Carioca MG, the most adapted, was increased in all of the 22 loci...
Tipo: Journal article
Palavras-chave: Bulk method; Fitness coefficient; Phaseolus vulgaris; SSR markers.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100005

Specific nutrient supplementation of defined serum-free medium for the improvement of CHO cells growth and t-PA production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Altamirano,Claudia; Illanes,Andrés; Canessa,Rossana; Becerra,Silvana.
Recombinant CHO TF70R cells are able to grow and produce t-PA on serum-free medium BIOPRO1 (BioWhitaker Europe, Belgium). The purpose of the present study was to determine the effect of medium supplementation with vitamins, lipids, and specific amino acids on cell growth, t-PA production and biological functionality. Among vitamins, only biotin, folic acid, cobalamine and benzoic acid were required for improving growth and t-PA production. Lipid supplement allowed a significant increase cell concentration and t-PA specific activity and concentration, though its specific production rate decreased slightly. Medium supplementation with proline, serine and asparagine had also positive effects on cell growth. Besides, the addition of asparagine (even in the...
Tipo: Journal article
Palavras-chave: Amino acid; Cholesterol; Vitamins.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100009

Biodegradation of two commercial herbicides (Gramoxone and Matancha) by the bacteria Pseudomonas putida
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kopytko,Maria; Chalela,Graciela; Zauscher,Fernando.
The purpose of this project was to evaluate the biodegradation of two commercial herbicides (Gramoxone and Matancha) by the bacteria Pseudomonas putida. Gramoxone’s active ingredient is Paraquat (1,1’-dimethyl-4,4’-bipyridylium) and Matancha’s is 2,4-D (2,4-dichlorophenoxiacetic acid). To carry out the biodegradation experiments, a factorial design 2³ was executed, where the independent variables were: herbicide concentration, nutrient concentration and the use or no use of activated charcoal (AC) in the same experiment with bacteria. Duplicate experiments were performed for a period of three days using 500 ml bioreactors. The best results obtained when no AC was used were: 47,29% degradation for Gramoxone (by UV/VIS) and 68.72% for Matancha (by HPLC). The...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200013

Lipopolyamine-mediated transfection of reporter plasmids into a fish cell line
Provedor de dados: Electronic Journal of Biotechnology
Autores: Villalobos,Patricio; Rojas,M. Verónica; Conejeros,Pablo; Marshall,Sergio H.
Conditions have been optimised to transfect the fish cell line CHSE-214 to measure expression, maintenance and putative chromosomal integration of the reporter gene LUC, spliced into two versions of an expression vector. The first is pCMVL, and the second p103, a novel pCMVL-derived plasmid to which a highly conserved tandem repeat from the salmon genome was added in an inverted configuration flanking the LUC gene to promote its chromosomal integration. A minimal ratio of one to one, lipopolyamine carrier to plasmid DNA, was enough to efficiently transfect the cell line to follow the fate of target DNAs up to five cell passages. In this time-span we demonstrated the maintenance of the foreign DNA in the cells, the concomitant expression of the reporter...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000200005

Ethics and Transgenic Crops: a Review
Provedor de dados: Electronic Journal of Biotechnology
Autores: Robinson,Jonathan.
This article represents a review of some of the ethical dilemmas that have arisen as a result of the development and deployment of transgenic crop plants. The potential for transgenic crops to alleviate human hunger and the possible effects on human health are discussed. Risks and benefits to the environment resulting from genetic engineering of crops for resistance to biotic and abiotic stresses are considered, in addition to effects on biodiversity. The socio-economic impacts and distribution of benefits from transgenic technologies are reviewed. Fundamental issues of man’s relationship with nature and the environment, and theological matters are also addressed. An almost unprecedented amount of discussion has been stimulated on the merits and demerits...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000200003

Growth responses of Betula pendula ecotypes to red and far-red light
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tsegay,Berhanu A.; Lund,Leidulf; Nilsen,Jarle; Olsen,Jorunn E.; Molmann,Jorgen M.; Ernsten,Arild; Juntttila,Olavi.
The effect of Red light (R), Far-red light (FR) and R/FR combinations on shoot growth of latitudinal ecotypes of B. pendula was studied using special diodes that emit monochromatic lights. When a 12 hrs PAR (110 &amp;micro;mol m-2 s-1) was extended with R, FR or R/FR ratios, lower intensities of monochromatic lights could not prevent growth cessation. At 25 &amp;micro;mol m-2 s-1, FR compared to R enhanced stem elongation in all ecotypes. This was due to the inhibitive effect of R on internode elongation. When day-length was extended by R/FR at various ratios, there was continuous shoot elongation, but was found to be declining with increasing ratios. The more the R, the shorter were the internodes of each plant. B. pendula ecotypes produced branches when...
Tipo: Journal article
Palavras-chave: Diode; Ecotype; Monochromatic; Photomorphogenesis; Phytochrome; Photosynthetically active radiation; PAR.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100005

Scientific research and training in biotechnology in Latin America and the Caribbean: the UNU/BIOLAC experience
Provedor de dados: Electronic Journal of Biotechnology
Autores: Daza,Camilo.
It is well known that the number of researchers in Biotechnology in Latin America and the Caribbean is too small to cope with the needs of research and to successfully confront the number of short and long-term problems. The United Nations University created its Biotechnology Program for Latin America and the Caribbean, UNU/BIOLAC, and the results of the efforts aiming to the promotion of a shared sense of direction within the region´s scientific community are presented and discussed herein.
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000200005

The challenges of introducing a new biofungicide to the market: A case study
Provedor de dados: Electronic Journal of Biotechnology
Autores: Galindo,Enrique; Serrano-Carreón,Leobardo; Gutiérrez,Carlos Roberto; Allende,Raúl; Balderas,Karina; Patiño,Martín; Trejo,Mario; Wong,Miguel Angel; Rayo,Emma; Isauro,Darío; Jurado,Carlos.
Background: Scientific literature contains many reports documenting the isolation and antagonist-testing of microorganisms with the potential for biological control in agriculture, however, very few have addressed all aspects involved in the long process that occurs before a potential strain, found and tested in laboratory, can reach commercialization. Results: After a multi-institutional and multi-disciplinary effort to develop a biological control agent with remarkable technical characteristics and performance, the fungicide Fungifree AB® was recently introduced in Mexican market. This product that has no chemical residues and is environmentally friendly which can be used by mango, avocado, papaya and citrus fruits (and other crops in the short term)...
Tipo: Journal article
Palavras-chave: Biofungicides; Fungicides; Fungifree AB®; Process biotechnology.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300005

On the fermentative behavior of auxotrophic strains of Saccharomyces cerevisiae
Provedor de dados: Electronic Journal of Biotechnology
Autores: Paciello,Lucia; Zueco,Jesus; Landi,Carmine.
Background The selection of new yeast strains could lead to improvements in bioethanol production. Here, we have studied the fermentative capacity of different auxotrophic mutants of Saccharomyces cerevisiae, which are routinely used as hosts for the production of heterologous proteins. It has recently been found that these strains exhibit physiological alterations and peculiar sensitivities with respect to the parental prototrophic strains from which they derive. In this work the performance of auxotrophic S. cerevisiae CEN.PK strains was compared to the corresponding prototrophic strain, to S. cerevisiae T5bV, a strain isolated from grape must and to another auxotrophic strain, S. cerevisiae BY4741. Results The results indicate that the fermentative...
Tipo: Journal article
Palavras-chave: Auxotrophic yeast; CEN.PK strains; Ethanol yields; Fermentative capacity; Fermentative metabolism.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000500009

Single embryoid body formation in a multi-well plate
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ezekiel,Uthayashanker R; Muthuchamy,Mariappan; Ryerse,Jan S; Heuertz,Rita M.
Embryoid bodies (EB) formed from murine embryonic stem (ES) cells recapitulate many aspects of a developing embryo. Of specific importance, synchronous differentiation of EB recapitulates organ-specific development and is achieved in culture by formation of uniformly sized EB. The method described here demonstrates a simple and cost-effective way of generating EB from murine ES cells. Single EB are formed in a multi-well plate format and large numbers of EB are generated using a 96-well multi-well plate. Uniform single-sized EB formed in the multi-well are an ideal system for screening compounds and determining differentiation effects. Since EB contain all three germ layers, they are appropriate for studying small molecule effects on differentiation of ES...
Tipo: Journal article
Palavras-chave: Differentiation; EB; ES; Murine embryonic stem cell.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200015

Antimicrobial peptides: A natural alternative to chemical antibiotics and a potential for applied biotechnology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Marshall,Sergio H.; Arenas,Gloria.
A large group of low molecular weight natural compounds that exhibit antimicrobial activity has been isolated from animals and plants during the past two decades. Among them, cationic peptides are the most widespread. Interestingly, the variety and diversity of these peptides seem to be much wider than suspected. In fact, novel classes of peptides with varying chemical propertiescontinue to be isolated from different vertebrate and invertebrate species, as well as from bacteria. To the early characterized peptides, mostly cationic in nature, anionic peptides, aromatic dipeptides, processed forms of oxygen-binding proteins and processed forms of natural structural and functional proteins can now be added, just to name a few. In spite of the astonishing...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300011

Improvement of nitrate and nitrite reduction rates prediction
Provedor de dados: Electronic Journal of Biotechnology
Autores: Estuardo,Carolina; Martí,M. Cristina; Huiliñir,César; Aspé Lillo,Estrella; Roeckel von Bennewitz,Marlene.
Reported models of denitrification rates integrate in an unique parameter the pH-dependent inhibition by HNO2 and the pH effect on the bacterial metabolic activity; furthermore, they do not quantify separately the pH effect on the nitrate and on the nitrite reduction rates. The goal of this work was to quantify both effects on the kinetics of nitrate and nitrite reduction to improve the models&amp;#8217; predictive value. Assays were performed at a pH range of 6.5-9.0 in batch reactors at 37ºC with an activated sludge. At the studied pH range and at below the HNO2 inhibitory concentration (0.004 mg L-1), the maximum nitrate reduction rate diminished 23% and 50% by decreasing or increasing, respectively, one pH unit from 8.0. The maximum nitrite reduction...
Tipo: Journal article
Palavras-chave: Denitrification kinetics; Nitrate reduction; Nitrite reduction; PH.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300008

Recombinant expression of marine shrimp lysozyme in Escherichia coli
Provedor de dados: Electronic Journal of Biotechnology
Autores: de-la-Re-Vega,Enrique; García-Orozco,Karina D; Calderón-Arredondo,Sergio A; Romo-Figueroa,María Gabriela; Islas-Osuna,María A.; Yepiz-Plascencia,Gloria M.; Sotelo-Mundo,Rogerio R.
Shrimp Lysozyme (Lyz) is a key component of the antibacterial response as part of the innate defense in Crustacea; however, it has not been possible to purify this protein because of the very low amount present in the shrimp blood cells (hemocytes). In an effort to produce enough protein to study its function and biochemical properties we have overexpressed Lysozyme from marine shrimp (Penaeus vannamei) in E. coli. A bacterial protein expression system based on the T7 polymerase promoter was used. Although Lyz was produced as insoluble protein in inclusion bodies, its refolding led to an active protein with a yield of ~10%. Details of the protein recombinant expression techniques applied to this shrimp protein are presented
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300012

Profiling carbohydrate composition, biohydrogen capacity, and disease resistance in potato
Provedor de dados: Electronic Journal of Biotechnology
Autores: Diez-de-Medina Roldán,Sergio; Silva,Herman; Jeblick,Wolfgang; Nowik,Isabella; Modigell,Michael; Neuhaus,H. Ekkehard; Conrath,Uwe.
Background: Potato (Solanum tuberosum) is one of the most important sources of carbohydrates in human diet. Because of its high carbohydrate levels it recently has also received attention in biohydrogen production. To exploit the natural variation of potato with respect to resistance to major diseases, carbohydrate levels and composition, and capacity for biohydrogen production we analyzed tubers of native, improved, and genetically modified potatoes, and two other tuberous species for their glucose, fructose, sucrose, and starch content. Results: High-starch potato varieties were evaluated for their potential for Caldicellulosiruptor saccharolyticus-mediated biohydrogen production with Desirée and Rosita varieties delivering the highest biohydrogen...
Tipo: Journal article
Palavras-chave: Biohydrogen; Caldicellulosiruptor saccharolyticus; Carbohydrates; Natural variation; Phytophthora infestans; Potato.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600002

An increasing of the efficiency of microbiological synthesis of 1,3-propanediol from crude glycerol by the concentration of biomass
Provedor de dados: Electronic Journal of Biotechnology
Autores: Szymanowska-Powalowska,Daria; Leja,Katarzyna.
Background 1,3-Propanodiol (1,3-PD), is used in the production of polytrimethylene terephthalate (PTT), an aromatic polyester that exhibits high elastic recoveries. It is also employed as a supplement with low solidification properties, a solvent and a lubricant in the formof propylene glycol. 1,3-PD is effectively synthesized by a microbiological way from crude glycerol. The main problem of this technology is using a high concentration of glycerol, which is a limiting factor for bacteria cells growth (especially in batch fermentation). Results In this work, the influence of different glycerol concentration in batch fermentation on Clostridium butyricum DSP1 metabolism was investigated. The biomass was concentrated for two times with the use of membrane...
Tipo: Journal article
Palavras-chave: C. butyricum; HSP protein; Microfiltration.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000200003

Two LTR retrotransposon elements within the abscisic acid gene cluster in Botrytis cinerea B05.10, but not in SAS56
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhao,Ming; Zhou,Jin yan; Tan,You jiu; Song,Wei wei; Li,Zhi dong; Tan,Hong.
The plant hormone abscisic acid has huge economic potential and can be applied in agriculture and forestry for it is considered to be involved in plant resistance to stresses such as cold, heat, salinity, drought, pathogens and wounding. Now overproducing strains of Botrytis cinerea are used for biotechnological production of abscisic acid. An LTR retrotransposon, Boty-aba, and a solo LTR were identified by in silico genomic sequence analysis, and both were detected within the abscisic acid gene cluster in B. cinerea B05.10, but not in B. cinerea SAS56. Boty-aba contains a pair of LTRs and two internal genes. The LTRs and the first gene have features characteristic of Ty3/gypsy LTR retrotransposons. The second gene is a novel gene, named brtn, which...
Tipo: Journal article
Palavras-chave: Botrytis cinerea; Genomic sequence analysis; In silico; LTR retrotransposon.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000100007

Identification of Saccharomyces cerevisiae strains for alcoholic fermentation by discriminant factorial analysis on electronic nose signals
Provedor de dados: Electronic Journal of Biotechnology
Autores: Calderon-Santoyo,Montserrat; Chalier,Pascale; Chevalier-Lucia,Dominique; Ghommidh,Charles; Ragazzo-Sanchez,Juan Arturo.
An electronic nose (E-nose) coupled to gas chromatography was tested to monitor alcoholic fermentation by Saccharomyces cerevisiae ICV-K1 and Saccharomyces cerevisiae T306, two strains well-known for their use in oenology. The biomass and ethanol concentrations and conductance changes were measured during cultivations and allowed to observe the standard growth phases for both yeast strains. The two strains were characterized by a very similar tendency in biomass or ethanol production during the fermentation. E-nose was able to establish a kinetic of the production of aroma compounds production and which was then easy to associate with the fermentation phases. Principal Component Analysis (PCA) showed that the data collected by E-nose during the...
Tipo: Journal article
Palavras-chave: Alcoholic fermentation; Discrimination; Electronic nose; Gas sensor; Yeasts.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400008

Isolation of high quality DNA: a protocol combining &amp;#8220;rennet&amp;#8221; and glass milk
Provedor de dados: Electronic Journal of Biotechnology
Autores: Valter de Oliveira,Luiz Felipe; Wallau,Gabriel da Luz; Silva Loreto,Elgion Lucio.
High quality DNA is essential for many molecular biology techniques. However, the reagents used for that purpose usually are expensive and/or cause a high environmental impact. Here, we describe two alternative protocols that use inexpensive reagents and are not hazardous to the environment. The first protocol utilizes the enzyme chymosin, normally used as &amp;#8220;rennet&amp;#8221; in cheese production and which is easily obtained on the commercial market. The second protocol uses &amp;#8220;rennet DNA extraction protocol&amp;#8221; combined with the DNA binding capacity of glass powder (glass milk), which can easily be &amp;#8220;home made&amp;#8221;. The first protocol is used when a high yield of DNA is needed, whereas the second protocol is used for...
Tipo: Journal article
Palavras-chave: Chymosin; DNA extraction; Glass milk; Rennet; Rennin; Silica.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200011

Bioinformatics: an essential tool for Biotechnology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Grau,Oscar.
Tipo: Journal article
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100001

Analysis and sequencing of h6hmRNA, last enzyme in the tropane alkaloids pathway from anthers and hairy root cultures of Brugmansia candida (Solanaceae)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cardillo,Alejandra B.; Giulietti,Ana M.; Marconi,Patricia L.
Brugmansia candida (Solanaceae) is a native tree distributed across South-American and produces the pharmacologically- important group of tropane alkaloids including scopolamine. This biocompound is synthesised from hyoscyamine by action of Hyoscyamine 6-&amp;beta; hydroxylase (H6H, EC 1.14.11.11) at the end of the tropane alkaloid pathway. Here are reported the tissue and organ-specific expression of h6hmRNA by RT-PCR analyses and the isolation, cloning and sequencing of the cDNA obtained from B. candida anthers and hairy root transformed cultures. Bioinformatic analysis of the nucleotide sequence revealed an uninterrupted ORF of 1038 bp and the predicted aminoacid sequence could be 344 aminoacid long. A database search showed that this sequence has high...
Tipo: Journal article
Palavras-chave: H6H; Hairy roots; Hyoscyamine; Scopolamine; Sequence analysis; Transformation.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300004

A quantitative PCR approach for determining the ribosomal DNA copy number in the genome of Agave tequila Weber
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rubio-Piña,Jorge; Quiroz-Moreno,Adriana; Sánchez-Teyer,L. Felipe.
Background: Agave tequilana has a great economic importance in Mexico in order to produce alcoholic beverages and bioenergy. However, in this species the structure and organization of the rDNAs in the genome are limited, and it represents an obstacle both in their genetic research and improvement as well. rDNA copy number variations per eukaryotic genome have been considered as a source of genetic rearrangements. In this study, the copy number of 18S and 5S rDNAs in the A. tequilana genome was estimated, and an absolute quantitative qPCR assay and genome size was used. In addition, an association between the rDNAs copy number and physical mapping was performed to confirm our results. Results: The analysis were successfully applied to determine copy number...
Tipo: Journal article
Palavras-chave: Agave tequilana; Copy number; Fluorescent in situ hybridization; Ribosomal DNA; Quantitative PCR.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400002

PCR assembly of synthetic human erythropoietin gene
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bustami,Yazmin; Yahya,Ahmad Ramli Mohd; Muhammad,Tengku Sifzizul Tengku; Shu-Chien,Alexander Chong; Abdullah,Amirul Al-Ashraf; Noor,Mohd Azizan Mohd; Arip,Yahya Mat.
Human erythropoietin (huEPO) is a glycoprotein with important physiological functions, such as erythropoiesis, angiogenesis, and wound healing. A therapeutic protein, huEPO is commonly used to treat patients suffering from renal and non-renal anemia. Recombinant human erythropoietin (rhuEPO) and endogenous huEPO are similar with respect to their biological and chemical properties. In this study, we describe the construction of synthetic huEPO gene to produce rhuEPO. The synthetic huEPO gene was constructed by overlapping oligonucleotides assembly and amplified by polymerase chain reaction (PCR). Twenty oligonucleotide sets, covering the huEPO gene sequence and two newly introduced restriction enzyme sites, were pulled together and amplified using Pfu DNA...
Tipo: Journal article
Palavras-chave: Cloning; Erythropoietin; Oligonucleotide assembly.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300011

Batch and fixed-bed column biosorption of manganese ion by Sargassum filipendula
Provedor de dados: Electronic Journal of Biotechnology
Autores: Henriques,Cristiane Assumpção; da Costa,Antonio Carlos Augusto; dos Reis,Marcelo Martins; Costa,André Luiz Hemerly; Luna,Aderval Severino.
This paper presents experimental data of the biosorption of manganese onto Sargassum filipendula in both batch and fixed-bed column systems. Batch equilibrium data were used for nonlinear fittings of the Langmuir and Freundlich isotherms. A mathematical model based on mass balances in the fluid and in the sorbent was applied to represent the experimental fixed-bed column data. The utilization of isotherm parameters from the batch experiments in the breakthrough model implied a significant mismatch in relation to the laboratory data. Alternatively, additional fixed-bed column data provided new parameters for the isotherm evaluation, and the corresponding simulated profile of the breakthrough curve reached better agreement to the experimental results.
Tipo: Journal article
Palavras-chave: Biosorption; Breakthrough curve; Equilibrium isotherm; Manganese; Metal removal.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500008

Postdoctoral Training in South America: Opportunities in Chile
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sobrado,Pablo.
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300016

Xylitol production and furfural consumption by a wild type Geotrichum sp.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Silveira Rocha Matos,Ítalo Thiago; do Carmo,Edson Júnior; Nogueira de Assunção,Enedina; Alves de Almeida,Richardson; Makarem Soares,Verena; Astolfi Filho,Spartaco.
Background: Xylitol is a five carbons polyol with promising medical applications. It can be obtained from chemical D-xylose reduction or by microbial fermentation of Sugarcane Bagasse Hemicellulosic Hydrolysate. For this last process, some microbial inhibitors, as furfural, constitute severe bottleneck. In this case, the use of strains able to produce xylitol simultaneously to furfural neutralization is an interesting alternative. A wild-type strain of Geotrichum sp. was detected with this ability, and its performance in xylitol production and furfural consumption was evaluated. Furthermore, were analyzed its degradation products. Results: Geotrichum sp. produced xylitol from D-xylose fermentation with a yield of 0.44 g-g-1. Furfural was fully consumed in...
Tipo: Journal article
Palavras-chave: Detoxification Sugarcane bagasse hemicellulosic hydrolysate Xylitol; D-Xylose reduction D-Xylose fermentation Microbial fermentation Furfural Sugarcane bagasse Hemicellulosic hydrolysate.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600003

Effect of laundry detergent formulation on the performance of alkaline phytoproteases
Provedor de dados: Electronic Journal of Biotechnology
Autores: Barberis,Sonia; Quiroga,Evelina; Barcia,Cristina; Liggieri,Constanza.
Background: Proteases constitute the largest product segment in the global industrial enzymes market; they are used in food, pharmaceutical, leather, textile, wood and detergent industries. Alkaline proteases improve the cleaning efficiency of detergents and represent one of the most successful applications of modern industrial biotechnology. The aim of this work was to study the performance of two alkaline phytoproteases, araujiain (Araujia hortorum Fourn.) and asclepain (Asclepias curassavica L.), for their potential application as additive in laundry detergent formulations. Results: The effect of pure non-ionic and ionic surfactants on proteolytic activity of araujiain and asclepain was analyzed measuring the remaining activity after 1 hr of incubation...
Tipo: Journal article
Palavras-chave: Asclepain; Araujiain; Detergents formulations; Alkaline plant proteases.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300003

Recovery of lead and cadmium ions from metal-loaded biomass of wild cocoyam (Caladium bicolor) using acidic, basic and neutral eluent solutions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Horsfall Jnr,Michael; Ogban,Fred E.; Akporhonor,Eyetemi E.
The effects of acidic, basic and neutral reagents on the recovery of Pb2+ and Cd2+ from metal-loaded biomass of wild cocoyam (C. bicolor) were investigated by eluting the biomass in five successive cycles using 0.01 M HCl, 0.1 M HCl, 0.01 M NaOH, 0.1 M NaOH and distilled water at different contact times. The data showed that the ease of metal ion recovery from metal -loaded biomass by the eluent solutions is of the order 0.01 M HCl &gt; 0.1 M HCl &gt; 0.01 M NaOH &gt; 0.1 M NaOH &gt; distilled water. Over 94% Pb2+ and 74% Cd2+ of the initially adsorbed metals were recovered by 0.01 M HCl, while &lt; 20% of both metals was recovered by basic reagent. Distilled water recovered less than 9% of both metal ions from the biomass. Macroscopic changes were also...
Tipo: Journal article
Palavras-chave: Cocoyam; Desorption; Heavy metals removal; Metal recovery; Water treatment.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200009

Methane hydrates in the Chilean continental margin
Provedor de dados: Electronic Journal of Biotechnology
Autores: Morales G.,Esteban.
In the coming years the worldwide energetic resources based on hydrocarbons will diminish, and methane hydrates can become an alternative source, given its huge deposits. Chile does not have great amounts of energetic resources; however, during the cruise C-2901 on board the R/V CONRAD in 1998, seismic profiles that took place in the Chilean continental margin between 35º and 45ºS show the presence of methane hydrates through BSR analysis. The following parameters for the hydrate layer can be assumed: Thickness = 100 m, Longitude E-W = 20 km, Latitude N-S = 1000 km, hydrate concentration in the sediments = 10%, and 160 m³ of gas per m³ of hydrate. With these figures, the volume of estimated gas is 3.2 x 10(13) m³.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000200002

Microbial Diversity and Ecosystem Functions - the Unmined Riches
Provedor de dados: Electronic Journal of Biotechnology
Autores: Weinbauer,Markus G.; Wenderoth,Dirk F.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100003

Immobilization of cyclodextrin glucanotransferase on aminopropyl-functionalized silica-coated superparamagnetic nanoparticles
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ibrahim,Abdelnasser S.S.; Al-Salamah,Ali A; El-Toni,Ahmed Mohamed; El-Tayeb,Mohamed A; Elbadawi,Yahya B.
Background: Cyclodextrin glycosyltransferase (CGTase) from Amphibacillus sp. NPST-10 was successfully covalently immobilized on aminopropyl-functionalized silica coated superparamagnetic nanoparticles; and the properties of immobilized enzyme were investigated. The synthesis process included preparing of core magnetic magnetite (Fe3O4) nanoparticles using solvothermal synthesis; followed by coating of Fe3O4 nanoparticles with dense amino-functionalized silica (NH2-SiO2) layer using in situ functionalization method. The structure of synthesized Fe3O4@NH2-SiO2 nanoparticles was characterized using TEM, XRD, and FT-IR analysis. Fe3O4@NH2-SiO2 nanoparticles were further activated by gluteraaldehyde as bifunctional cross linker, and the activated nanoparticles...
Tipo: Journal article
Palavras-chave: Amphibacillus sp. NPST-10; Cyclodextrin glucanotransferase; Immobilization; Magnetic nanoparticle; Silica.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600010

Building Biotechnology: Starting, Managing, and Understanding Biotechnology Companies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Marshall,Sergio.
Tipo: Journal article
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100002

Bioconversion of cassava starch by-product into Bacillus and related bacteria polyhydroxyalkanoates
Provedor de dados: Electronic Journal of Biotechnology
Autores: Krueger,Cristhiane L; Radetski,Claudemir M; Bendia,Amanda G; Oliveira,Ida M; Castro-Silva,Marcus A; Rambo,Carlos R; Antonio,Regina V; Lima,André O.S.
Background: Unlike petroleum-based synthetic plastics, biodegradable biopolymer generation from industrial residue is a key strategy to reduce costs in the production process, as well as in the waste management, since efficient industrial wastewater treatment could be costly. In this context, the present work describes the prospection and use of bacterial strains capable to bioconvert cassava starch by-product into biodegradable polyhydroxyalkanoates (PHAs). Results: The first step of this study was the bacterial competence screening which was conducted with 72 strains covering 21 Bacillus and related species. The microorganism growth in a medium with a starch substrate was measured by an innovative MTT assay, while the ability of the bacteria to secrete...
Tipo: Journal article
Palavras-chave: Bacillus megaterium; Biodegradable plastics; Biopolymer; MTT assay; Starch substrates.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000300008

The inhibitory effect of biofilms produced by wild bacterial isolates to the larval settlement of the fouling ascidia Ciona intestinalis and Pyura praeputialis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zapata,Manuel; Silva,Fernando; Luza,Yery; Wilkens,Marcela; Riquelme,Carlos.
Marine biofouling is a present and potentially increasing future problem at molluscan culture centres. The problem is highly variable, exists on different scales, and its negative impact on cultured organisms and related economic losses at these centres has not been significantly controlled. One approach to fouling control has been the incorporation of natural substances into anti-fouling paints which inhibit the settlement of common fouling organisms. The main objective of the present study was the isolation of naturally occurring substances from marine bacteria which were inhibitory to the settlement of Ciona intestinalis and Pyura praeputialis, two tunicate species causing serious fouling problems in scallop culture systems in Chile. Numerous bacterial...
Tipo: Journal article
Palavras-chave: Antifouling extracts; Ascidian bioassays; Bacterial biofilms; Ciona intestinalis; Marine biofouling; Natural antifoulants; Pyura praeputialis.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100014

Endogenous GUS-like activity in Capsicum chinense Jacq
Provedor de dados: Electronic Journal of Biotechnology
Autores: Solís-Ramos,Laura Yesenia; González-Estrada,Tomas; Andrade-Torres,Antonio; Godoy-Hernández,Gregorio; Castaño de la Serna,Enrique.
The gene uidA, codes for &amp;#946;-glucuronidase, which is one of the reporters more frequently utilized in transgenic plants. However, this can only be use if the selected organism does not present endogenous GUS-like activity. In tissues of C. chinense we found a GUS-like activity showing different levels of intensity. Histochemical screening showed that endogenous GUS-like activity decreased, or reduced significantly, in almost all tissues with exception of stament, when phosphate buffer was adjusted to pH 8. Subsequently, C. chinense zygotic embryo explants were transient transformed with Agrobacterium tumefaciens LBA4404 (pCAMBIA2301) and plantlets regenerated were histochemically stained in phosphate buffer pH 8. Observations of incubated tissues of...
Tipo: Journal article
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400002

Comparative esterification of phenylpropanoids versus hydrophenylpropanoids acids catalyzed by lipase in organic solvent media
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cassani,Julia; Luna,Héctor; Navarro,Arturo; Castillo,Edmundo.
The esterification of phenylpropanoid and hydrophenylpropanoid acids, catalyzed by candida antarctica lipase B (CAL-B), with several alcohols has demonstrated that the substitution pattern on the aromatic ring has a very significant influence on the reactivity of the carboxyl group due, mainly, to electronic effects, when compared to the unsaturated acids with the hydrogenated acids. It is also clear that in the saturated acids there still remain some unclear effects related to the aromatic substituents.
Tipo: Journal article
Palavras-chave: CAL-B; Electronic effects; Esterification; Lipase; Phenylpropanoid acids.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400004

Degradation of citronellol, citronellal and citronellyl acetate by Pseudomonas mendocina IBPse 105
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tozoni,Daniela; Zacaria,Jucimar; Vanderlinde,Regina; Delamare,Ana Paula Longaray; Echeverrigaray,Sergio.
The purpose of this work was to stud the biodegradation of citronellol, citronellal and citronellyl acetate by a soil Pseudomonas mendocina strain (IBPse 105) isolated from a Cymbopogon windelandi field. This strain efficiently used citronellol, citronellal, citronellyl acetate and myrcene as sole source of carbon, but was not able to grow on other 15 monoterpenoids evaluated. Gas chromatography-mass spectrometry (GC-MS) analysis of metabolites accumulation during P. medocina IBPse 105 growth on citronellol showed that this strain uses the citronellol catabolic pathway described for other species of the genus. IBPse 105 degradation of citronellyl acetate initiates by its hydrolysis to citronellol. The mini-Tn5 insertion in mutant IBPse 105-303, impaired in...
Tipo: Journal article
Palavras-chave: Biodegradation; Citronellol catabolism; Monoterpenes degradation; P. mendocina.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000200002

Spirulina platensis growth estimation by pH determination at different cultivations conditions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pelizer,Lúcia Helena; Carvalho,J.C.M.; Sato,Sunao; de Oliveira Moraes,Iracema.
Spirulina platensis is a cyanobacterium that has a high protein content and therefore, a high nutritional value. It can be cultivated either in a liquid or in a solid culture. When cultivated in aqueous culture the cell growth can be determined by following the optical density. On the other hand, when produced by solid cultivation the growth can be determined only indirectly, such as, through determination of the protein content of the fermenting solids. In this work the possibility of estimating cell growth by pH determination was verified. From the results it was concluded that pH and protein production (solid or surface culture) or cell content (liquid culture) correlate well, therefore pH determination seems to be a good method to determine cell growth.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300009

Improvement of SCP production and BOD removal of whey with mixed yeast culture
Provedor de dados: Electronic Journal of Biotechnology
Autores: Moeini,Hassan; Nahvi,Iraj; Tavassoli,Manoochehr.
This research emphasizes on single cell protein (SCP) production and Biochemical Oxygen Demand (BOD) removal from whey with mixed yeast culture. For this purpose, 11 yeast strains were isolated from dairy products (M1-M11) and the strains were identified by morphological and physiological properties. These yeast strains were tested for their ability to reduce the BOD and to produce SCP from whey. Among these strains, K. lactis (M2) had the most SCP production from whey with the yield of 11.79 g/l. Ammonium sulphate as nitrogen source had an increasing effect on biomass yield. The mixed culture of the isolated yeast strains with Saccharomyces cerevisiae was used in order to increase the biomass yield and BOD removal. The highest biomass yield (22.38 g/l)...
Tipo: Journal article
Palavras-chave: Beta-galactosidase; BOD; Candida versatilis; Kluyveromyces lactis; Kluyveromyces marxianus; Mixed culture; SCP; Whey.
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300006

Simple method to prepare DNA templates from a slice of peanut cotyledonary tissue for Polymerase Chain Reaction
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yu,Shu Tao; Wang,Chuan Tang; Yu,Shan Lin; Wang,Xiu Zhen; Tang,Yue Yi; Chen,Dian Xu; Zhang,Jian Cheng.
An efficient DNA extraction method was developed for peanut seed, where only 3-5 mg cotyledonary tissue was enough for more than 50 PCR reactions with a reaction volume of 15 &amp;#956;l. Both low copy number and high copy number DNA sequences were successfully amplified. Processing one seed sample only took about half an hour. Sampling had no significant effects on germination and development. The DNA extraction method makes it possible to identify transformants and conduct molecular marker studies prior to sowing, and thus may greatly hasten research progress.
Tipo: Journal article
Palavras-chave: Cotyledonary tissue; DNA extraction; Groundnut; PCR; Peanut.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400012

Selection of polyvalent bacteriophages infecting Salmonella entérica serovar Choleraesuis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Parra,Bárbara; Robeson,James.
Background: Ideally, bacteriophages of pathogenic bacterial hosts should be polyvalent to be able to replicate in an alternative nonpathogenic bacterium. Thus, accidental infection by the original host can be avoided when bacteriophage lysates are used in biocontrol protocols. Results: From 15 wastewater samples, collected at different sites in the V Region in Chile, we selected three bacteriophages (FC, FP, and FQ) capable of productively infecting Salmonella enterica serovar Choleraesuis. By transmission electron microscopy (TEM) observation, the bacteriophages were found to belong to the order Caudoviridae. Molecular analyses indicated that FC, FP, and FQ contained double-stranded DNA genomes, of sizes similar to bacteriophage P22, and distinct...
Tipo: Journal article
Palavras-chave: Bacteriophage; Polyvalent; Salmonella enterica serovar Choleraesuis.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300011

Transfer and expression of the genes of Bacillus branched chain alpha-oxo acid decarboxylase in Lycopersicun esculentum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang-Pruski,Gefu; Szalay,Aladar A.
Engineering of higher plants for increased cold tolerance requires a chemical modification of membrane fluidity in both organelles and cytoplasm of plant cells. A small number of microorganisms use branched chain fatty acids as their membrane constituents to maintain membrane fluidity, instead of unsaturated fatty acids. One of the key enzymes facilitating synthesis of branched chain fatty acids in Bacillus subtilis 168s is the branched chain alpha-oxo acid decarboxylase. To examine the role of branched chain fatty acids in plants and the potential for low temperature tolerance, the A and B genes encoding the alpha and beta polypeptides, respectively, of the branched chain alpha-oxo acid decarboxylase were introduced into the genome of tomato plants. The...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200009

Glucose and other hexoses transporters in marine invertebrates: A mini review
Provedor de dados: Electronic Journal of Biotechnology
Autores: Martínez-Quintana,José Alfredo; Yepiz-Plascencia,Gloria.
Glucose and related hexoses are very important metabolic substrates. Their most important function is to provide quick fuel for most organisms in all three kingdoms because they are the first substrate for energy production in the form of ATP through glycolysis and the subsequent metabolic pathways. In this paper we review the current information about how glucose and related hexoses are transported across biological membranes to carry out their function either as a metabolic molecule or as energy store in marine invertebrate organisms. In these animals, there are two sugar transport systems that are mediated by the sodium/solute symporter family proteins (SGLT) and the major facilitative super-family proteins (GLUT). The most studied sugar transporters in...
Tipo: Journal article
Palavras-chave: Facilitative; GLUT; SGLT; Sodium-dependent; Transport.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500016

A predicted structure of the cytochrome c oxidase from Burkholderia pseudomallei
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mohd. Raih,Mohd. Firdaus; Sailan,Ahmad Tarmidi; Zamrod,Zulkeflie; Embi,Mohd. Noor; Mohamed,Rahmah.
Cytochrome c oxidase, the terminal enzyme of the respiratory chains of mitochondria and aerobic bacteria, catalyzes electron transfer from cytochrome c to molecular oxygen. The enzyme belongs to the haem-copper-containing oxidases superfamily. A recombinant plasmid carrying a 2.0 kb insert from a Burkholderia pseudomallei genomic library was subjected to automated DNA sequencing utilizing a primer walking strategy. Analysis of the 2002 bp insert revealed a 1536 bp open reading frame predicted to encode a putative cytochrome c oxidase. Further analysis using sequence alignments and tertiary structure analysis tools demonstrated that the hypothetical B. pseudomallei cytochrome c oxidase is similar to cytochrome c oxidases from other organisms such as Thermus...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000100005

RAPD analysis of seized marijuana (Cannabis sativa L.) in Turkey
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pinarkara,Emine; Kayis,Seyit A; Hakki,Erdogan E; Sag,Ayla.
Cannabis sativa L. is a multiple-use plant. However, its cultivation is strictly controlled due to its psychoactive nature and usage in producing drugs such as marijuana, and hashish. In this study, psychoactive type Cannabis samples, which were seized from 29 different locations of Turkey, were used. Interests were to identify the genetic relatedness of the seized samples and to partition molecular variance between and within populations. Randomly Amplified Polymorphic DNAs were employed for analysis based on single plant material and bulked samples of them. Data were analysed via cluster and principal coordinate analyses (PCoA). Analysis of molecular variance (AMOVA) was performed to obtain variations between and within populations. Cannabis accessions...
Tipo: Journal article
Palavras-chave: AMOVA; Cluster analysis; Individualization of seized marijuana; Principle coordinate analysis; Randomly amplified polymorphic DNA; UPGMA.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000100005

Agronomic and molecular analyses for the characterisation of accessions in Tunisian olive germplasm collections
Provedor de dados: Electronic Journal of Biotechnology
Autores: Taamalli,Wael; Geuna,Filippo; Banfi,Riccardo; Bassi,Daniele; Daoud,Douja; Zarrouk,Mokhtar.
In this study, a total of 14 agronomic traits, five AFLP primer combinations and ten SSR loci were used to describe and to classify a group of Tunisian olive genotypes into groups based on molecular profiles and agronomic traits. The analysis of variance of the agronomical data revealed significant differences among accessions for all measured traits. The mean phenotypic dissimilarity (0.34 with a range of 0.08-0.6) was low in comparison to dissimilarity calculated using AFLP (0.50 with a range of 0.16-0.70) and SSR markers (0.76 with a range 0.35-0.94). The correlation between the agronomical dissimilarity matrix and the matrices of genetic dissimilarity based on SSR and AFLP markers was very weak: 0.156 (p = 0.05) and 0.185 (p = 0.05), respectively. The...
Tipo: Journal article
Palavras-chave: Agronomic traits; AFLP; Olea europaea; SSR.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500002

Sheep 7SK promoter for short hairpin RNA expression
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ni,Wei; Hu,Shengwei; Hazi,Wureli; Wang,Yuanzhi; Qiao,Jun; Yan,Ren; Chen,Chuangfu.
Background: Gene silencing mediated by small interfering RNA (siRNA) has become a powerful biological tool for the regulation of gene expression. For the synthesis of siRNA by vector-based expression systems, several mammalian small nuclear RNA (snRNA) promoters have been cloned and shown different transcriptional efficiencies. Results: In this study, we identified a sheep 7SK snRNA (s7SK) promoter based on the highly conserved polymerase III promoter elements. Promoter activity was measured by promoter-driven shRNA expression to suppress expression of an exogenous reporter gene and endogenous sheep gene. Conclusions: The knock down assay demonstrated that the s7SK induced more stronger inhibition effect than human U6 and H1 promoters. The use of this...
Tipo: Journal article
Palavras-chave: 7SK promoter; RNAi; Sheep; ShRNA.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000200010

Scavenging of nickel and chromium toxicity in Aulosira fertilissima by immobilization:: Effect on nitrogen assimilating enzymes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Banerjee,Meenakshi; Mishra,Shanoo; Chatterjee,Jhuma.
The ubiquity of heavy metals in the biosphere results in the introduction of high amounts of toxic metals into the food chain from various sources. In the present study, one of the strongest nitrogen fixing cyanobacterium of the rice fields, Aulosira fertilissima, was subjected to nickel and chromium stress and the ameliorating effect of immobilization was investigated. Cell immobilization could protect the organism&amp;rsquo;s growth against the toxicity of both heavy metals at LC50 as compared to lethal concentrations. The nitrate reductase activity in free cells treated with the metals was substantially inhibited but immobilized cells treated with 0.1 ppm nickel was not affected by the metal treatment. Cell immobilization also resulted in a significant...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300013

Peroxidase production from hairy root cultures of red beet (Beta vulgaris)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rudrappa,Thimmaraju; Neelwarne,Bhagyalakshmi; Kumar,Vinod; Lakshmanan,Venkatachalam; Venkataramareddy,Sreedhar Reddampalli; Aswathanarayana,Ravishankar Gokare.
The genetically transformed roots of red beet have been shown, for the first time, to produce very high levels of peroxidase (POD; EC 1.11.1.7) accounting for 1.21 x 10(6) Units L-1. Of the ten clones established using different strains of Agrobacterium rhizogenes, one was that from the strain LMG-150, three each from A 2/83, A 20/83 and A4. All the clones showed true integration of T-DNA when tested by PCR and Southern hybridization methods. Each clone differed significantly from the others in growth, hormone dependency and POD production where LMG-150 produced highest biomass (140 g FW L-1) as well as POD (ranging from 8000-9000 U g-1 FW and 1.18 x 10(6) U L-1 with a specific activity of 600 U mg-1 protein) on hormone-free medium, both in shake-flask as...
Tipo: Journal article
Palavras-chave: Agrobacterium rhizogenes; Auxins; Elicitation; T-DNA; Thermostability; Transformation.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200008

Effect of cytokinin types, concentrations and their interactions on in vitro shoot regeneration of Chlorophytum borivilianum Sant. &amp;amp; Fernandez
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ashraf,Mehdi Farshad; Aziz,Maheran Abd; Kemat,Nurashikin; Ismail,Ismanizan.
Background Chlorophytum borivilianum is a rare medicinal plant originally distributed throughout the forest of India. The tubers of C. borivilianum are used as an aphrodisiac and impotence supplement. The propagation of C. borivilianum is possible through seeds and tubers, but conventional methods may take several months. Hence in vitro technique of shoot regeneration could be an efficient alternative means of propagating the species. Latest study reported microtuberization of C. borivilianum but there is no sufficient study on a rapid method for shoot multiplication and elongation. Results Young shoot buds of C. borivilianum were cultured on MS medium containing 6-benzylaminopurine (BAP) and Kinetin (Kn), both at 0, 8.88, 17.8 and 26.6 µM, either...
Tipo: Journal article
Palavras-chave: Chlorophytum borivilianum; Cytokinin interaction; Shoot multiplication.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600004

Decline of genetic variability in a captive population of Pacific white shrimp Penaeus (Litopenaeus) vannamei using microsatellite and pedigree information
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vela Avitúa,Sergio; Montaldo,Hugo H; Márquez Valdelamar,Laura; Campos Montes,Gabriel R; Castillo Juárez,Héctor.
Background: The objective of this study was to estimate the decline of genetic variability and the changes in effective population size in three shrimp populations. One was a wild population collected at several points in the Mexican Pacific Ocean. The other two populations were different generations (7 and 9) from a captive population selected for growth and survival. Microsatellite markers and pedigree were both used to assess genetic variability and effective population size. Results: Using 26 loci, both captive populations showed a decline in the expected heterozygosity (20%) and allelic diversity indices (48 to 91%) compared to the wild population (P &lt; 0.05). The studied captive populations did not differ significantly from each other regarding...
Tipo: Journal article
Palavras-chave: Effective population size; Genetic diversity; Heterozygosity; Microsatellites; Selection; Shrimp.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400009

Compilation of an informative microsatellite set for genetic characterisation of East African finger millet (Eleusine coracana)
Provedor de dados: Electronic Journal of Biotechnology
Autores: De Villiers,Santie M; Michael,Vincent N; Manyasa,Eric O; Saiyiorri,Annis N; Deshpande,Santosh.
Background Genetic diversity of finger millet (Eleusine coracana), a nutritious neglected staple cereal in Africa and South Asia is largely uncharacterized. This study analysed 82 published SSR markers for finger millet across 10 diverse accessions to compile an informative set for genetic characterisation. Extensive optimization compared single samples with bulked leaf or bulked DNA samples for capturing within accession genetic diversity. The markers were evaluated to determine (1) how efficiently they amplified target loci during high-throughput genotyping with a generic PCR protocol, (2) ease of scoring PCR products and (3) polymorphism and ability to discern genetic diversity within the tested finger millet germplasm. Results Across 88 samples, the 52...
Tipo: Journal article
Palavras-chave: Diversity analysis; SSR markers; Genotyping.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200003

Metabolic engineering: Use of system-level approaches and application to fuel production in Escherichia coli
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gonzalez,Ramon.
Metabolic engineering was formally defined more than two decades ago (Bailey, 1991) and it is now an established discipline. Metabolic engineering is generally defined as the directed improvement of product formation or cellular properties through the modification of specific biochemical reactions or the introduction of new ones with the use of recombinant DNA technology (Bailey, 1991; Stephanopoulos et al. 1998). Therefore, the analysis and engineering/synthesis of metabolic pathways is of central importance to metabolic engineering. The analytical part uses a number of experimental and modeling techniques for the systematic study of cellular responses (in terms of RNA, protein and metabolite levels, metabolic fluxes, etc.) to genetic and environmental...
Tipo: Journal article
Palavras-chave: Biofuels; Escherichia coli; Metabolic engineering; Systems biology.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300017

Whey upgrading by enzyme biocatalysis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Illanes,Andrés.
Whey is a co-product of processes for the production of cheese and casein that retains most of the lactose content in milk. World production of whey is estimated around 200 million tons per year with an increase rate of about 2%/per year. Milk production is seasonal, so surplus whey is unavoidable. Traditionally, whey producers have considered it as a nuisance and strategies of whey handling have been mostly oriented to their more convenient disposal. This vision has been steadily evolving because of the upgrading potential of whey major components (lactose and whey proteins), but also because of more stringent regulations of waste disposal. Only the big cheese manufacturing companies are in the position of implementing technologies for their recovery and...
Tipo: Journal article
Palavras-chave: Beta-galactosidase; Enzyme catalysis; Lactose; Oligosaccharides; Prebiotics; Whey.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600009

AgNO3: a potential regulator of ethylene activity and plant growth modulator
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kumar,Vinod; Parvatam,Giridhar; Ravishankar,Gokare Aswathanarayana.
The aim of this review is to critically analyze the role of silver nitrate (AgNO3) in modulating plant growth and development. In recent years, basic studies on ethylene regulation opened new vistas for applied research in the area of micro-propagation, somatic embryogenesis, in vitro flowering, growth promotion, fruit ripening, and sex expression. Silver nitrate has proved to be a very potent inhibitor of ethylene action and is widely used in plant tissue culture. Few properties of silver nitrate such as easy availability, solubility in water, specificity and stability make it very useful for various applications in exploiting plant growth regulation and morphogenesis in vivo and in vitro. Silver ion mediated responses seem to be involved in polyamines,...
Tipo: Journal article
Palavras-chave: Calcium; Ethylene; Morphogenesis; Polyamines; Silver nitrate; Somatic embryogenesis.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200008

A fast and simple assay to quantify bacterial leukotoxin activity
Provedor de dados: Electronic Journal of Biotechnology
Autores: Oppermann,Tobias; Schwarz,Stefan; Busse,Nadine; Czermak,Peter.
Background: Mannheimia haemolytica is the primary bacterial pathogen in causing bovine respiratory disease with tremendous annual losses in the cattle industry. The leukotoxin from M. haemolytica is the predominant virulence factor. Several leukotoxin activity assays are available but not standardized regarding sample preparation and cell line. Furthermore, these assays suffer from a high standard error, a prolonged time consumption and often complex sample pretreatments, which is important from the bioprocess engineering point of view. Results: Within this study, an activity assay based on the continuous cell line BL3.1 combined with a commercial available adenosine triphosphate viability assay kit was established. The leukotoxin activity was found to be...
Tipo: Journal article
Palavras-chave: ATP assay; Bacterial pathogen; Bovine respiratory disease; Cattle industry; Critical parameters; Lipopolysaccharides; Mannheimia haemolytica; Microbial biotechnology; Polymyxin B; Quantification; Virulence.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600006

Micropropagation of Lilium ledebourii (Baker) Boiss as affected by plant growth regulator, sucrose concentration, harvesting season and cold treatments
Provedor de dados: Electronic Journal of Biotechnology
Autores: Azadi,Pejman; Khosh-Khui,Morteza.
A protocol for the micropropagation in different harvesting time of Lilium ledebourii (Baker) Boiss, an endangered rare species endemic to Iran has been developed. In vitro scale culture of this species, using bulbs from three harvesting seasons (spring, summer and winter), was attempted. Among the various treatments tested, the Murashige and Skoog (MS) medium supplemented with 0.1 mg l-1 naphthaleneacetic acid (NAA) + 0.1 mg l-1 benzyladenin (BA) and 6% sucrose in all harvesting seasons proved to be superior to others. The best results for fresh weight of bulblets, rooting parameters and the survival rate after transplantation to greenhouse were obtained from early winter-harvested bulbs. Summer-harvested bulbs had the highest number of bulblets per...
Tipo: Journal article
Palavras-chave: Bulblet; Cold treatment; Conservation; Harvesting season; Lilium ledebourii; Tissue culture.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400011

Taking a lead in applied mining biotechnology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Badilla-Ohlbaum,Ricardo.
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200001

The exopolysaccharides biosynthesis by Candida yeast depends on carbon sources
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gientka,Iwona; Bzducha-Wróbel,Anna; Stasiak-Rózañska,Lidia; Agnieszka Bednarska,Aleksandra; Blazejak,Stanislaw.
Background: The exopolysaccharides (EPS) produced by yeast exhibit physico-chemical and rheological properties, which are useful in the production of food and in the cosmetic and pharmaceutical industries as well. The effect was investigated of selected carbon sources on the biosynthesis of EPS by Candida famata and Candida guilliermondii strains originally isolated from kefirs. Results: The biomass yields were dependent on carbon source (sucrose, maltose, lactose, glycerol, sorbitol) and ranged from 4.13 to 7.15 g/L. The highest biomass yield was reported for C. guilliermondii after cultivation on maltose. The maximum specific productivity of EPS during cultivation on maltose was 0.505 and 0.321 for C. guilliermondii and C. famata, respectively. The...
Tipo: Journal article
Palavras-chave: Candida; Exopolysaccharides biosynthesis; EPS; Maltose.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400005

The potential use of anoxygenic phototrophic bacteria for treating latex rubber sheet wastewater
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kantachote,Duangporn; Torpee,Salwa; Umsakul,Kamontam.
A total of 92 isolates of the purple non sulphur photosynthetic bacteria (PNSB) were isolated from 23 samples of wastewater obtained from rubber sheet manufacturing processes from various places of southern, Thailand. The isolate DK6 had the best potential for use in wastewater treatment as it can out-compete indigenous strains of PNSB when grown with them under conditions of microaerobic-light conditions. The isolate DK6 was identified as being most closely allied to Rhodopseudomonas blastica. The optimal pH and temperature for cell growth were between 6.5-7.5 and 30&amp;ordm;C, respectively. Optimum growth of DK6 was obtained after supplementing the wastewater from a latex rubber sheet processing plant with 0.50% (NH4)2SO4 and 1 mg/L nicotinic acid under...
Tipo: Journal article
Palavras-chave: Biochemical oxygen demand(BOD); Chemical oxygen demand(COD); Purple non sulphur photosynthetic bacteria (PNSB); Rubber sheet wastewater; Single cell protein (SCP).
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300012

Detection of single nucleotide polymorphisms in the conserved ESTs regions of Gossypium arboreum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Shaheen,Tayyaba; Zafar,Yusuf; Mehboob-ur-Rahman,.
Exploring genetic variation in Gossypium arboreum L. germplasm is useful as it contains many important genes conferring resistance to different stresses. In limited earlier studies, low level of genetic diversity was found by using conventional DNA marker systems which may impede future genome mapping studies. In the present investigation, we explored the extent of Single Nucleotide Polymorphisms (SNP) among 30 conserved regions of Expressed Sequence Tags (EST) of low copy genes between two genotypes of G. arboreum. A total of 27 SNPs including 21 substitutions and 6 Insertions and deletions (Indels) in 7804 bp were found between these genotypes with a frequency of one SNP per 371 bp and one Indel after every 1300 bp. Out of these SNPs, 52% were...
Tipo: Journal article
Palavras-chave: Conserved regions; Gossypium arboretum; SNPs.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500003

Oligomerization of Cry9Aa in solution without receptor binding, is not related with insecticidal activity
Provedor de dados: Electronic Journal of Biotechnology
Autores: Fang,Longfa; Wang,Bo; Zhou,Zishan; Yang,Sujuan; Shu,Changlong; Song,Fuping; Bravo,Alejandra; Soberón,Mario; Zhang,Jie.
Background: Bacillus thuringiensis Cry toxins bind with different insect midgut proteins leading to toxin oligomerization, membrane insertion and pore formation. However, different Cry toxins had been shown to readily form high molecular weight oligomers or aggregates in solution in the absence of receptor interaction. The role of Cry oligomers formed in solution remains uncertain. The Cry9A proteins show high toxicity against different Lepidoptera, and no-cross resistance with Cry1A. Results: Cry9Aa655 protein formed oligomers easily in solution mediated by disulfide bonds, according to SDS-PAGE analysis under non-reducing and reducing conditions. However, oligomerization is not observed if Cry9Aa655 is activated with trypsin, suggesting that cysteine...
Tipo: Journal article
Palavras-chave: Cry9Aa655; Disulfide bonds; Oligomerization; Insecticidal activity.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300006

Characterization of the genetic structure of mango ginger (Curcuma amada Roxb.) from Myanmar in farm and genebank collection by the neutral and functional genomic markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jatoi,Shakeel Ahmad; Kikuchi,Akira; Ahmad,Dawood; Watanabe,Kazuo N.
A preliminary characterization was undertaken to describe genetic structure of mango ginger (Curcuma amada) acquired from farmers and ex situ genebank in Myanmar using neutral (rice SSR based RAPDs) and functional genomic (P450 based analog) markers. The high polymorphism (&gt; 91%) depicted has displayed existence of genetic variability in the germplasm investigated. Large number of source-specific alleles (neutral-markers = 78, functional-markers = 63) was amplified which revealed that neutral regions of the mango ginger were more variable compared with the functional regions. The major fraction of the molecular variance (neutral-markers = 85%, functional-markers = 93%) was explained within germplasm acquisition sources and this tendency was also...
Tipo: Journal article
Palavras-chave: Curcuma amada; Genetic diversity; Mango-ginger; Myanmar; On-farm.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600004

The Colours of Biotechnology: Science, Development and Humankind
Provedor de dados: Electronic Journal of Biotechnology
Autores: DaSilva,Edgar J.
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300001

Phylogenetic relationships among species of the subsection Dendrophlomis Bentham
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yuzbasioglu,Ertugrul; Dadandi,Mehmet Yasar.
This study used randomly amplified polymorphic DNA markers to determine genetic relationships among species of the subsection Dendrophlomis. Twenty accessions of the eleven Phlomis taxa were evaluated to determine genetic variability using fourteen ten mer primers selected from a 125 random oligonucleotide set. These 14 selected primers generated 85 RAPD bands that ranged in size from 200 to 1200 base pairs. Of the total bands, 88% (75) were polymorphic among the samples. Genetic distances among accessions were computed to produce a dendrogram based on UPGMA. Genetic distances ranged from 0.133 (between P. amanica and P. monocephala) to 0.494 (between P. chimerae and P. lunariifolia). The UPGMA tree based on distances has two major groups. The first...
Tipo: Journal article
Palavras-chave: Genetic diversity; Genetic relationships; Genetic variation; Phlomis species; RAPDs.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400012

Identification of unknown genetically modified material admixed in conventional cotton seed and development of an event-specific detection method
Provedor de dados: Electronic Journal of Biotechnology
Autores: Akritidis,Paschalis; Pasentsis,Konstantinos; Tsaftaris,Athanasios S; Mylona,Photini V; Polidoros,Alexios N.
Entering the second decade of commercialization of biotech crops, the global area cultivated with transgenic plants constantly expands and national legislations in many countries, particularly in the European Union, require identification and labeling of genetically modified material in food and feed. We describe here a procedure for characterizing transgenic material of unknown origin present in conventional seed lots using a genome walking strategy for isolation and characterization of the junction between the inserted transgene construct and the host plant genomic DNA. The procedure was applied to transgenic cotton detected as adventitious or technically unavoidable presence in a conventional commercial cultivar. The structure of the isolated region...
Tipo: Journal article
Palavras-chave: Event specific detection; Genetically modified cotton; Genome walking; GMO detection; Mon1445.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200010

Induction of the expression of defence genes in Carica papaya fruit by methyl jasmonate and low temperature treatments
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rivera-Domínguez,Marisela; Astorga-Cienfuegos,Karen Rosalinda; Tiznado-Hernández,Martin Ernesto; González-Aguilar,Gustavo Adolfo.
The defence mechanisms that are activated by methyl jasmonate (MJ) in fruits are not well understood. In this work, we studied the expression of defence genes in papaya fruit that are induced by the exposure to MJ and/or low temperatures. The papaya fruits &amp;#145;Maradol&amp;#146; were randomly divided into two groups: one group was the untreated control and the other was treated with 10-4 M of MJ. Half of the fruits from each of the two groups were stored after treatment for 5 days at 5ºC and 2 days at 20ºC. We studied the expression levels of the pdf1.1 and pdf1.2 genes by amplification from expression libraries created from the pulp and skin tissues of the papaya fruit. As a reference, the mRNA level of the 18s ribosomal gene was used. In the skin...
Tipo: Journal article
Palavras-chave: Cold treatment; Defence proteins; Genetic expression; Jasmonic acid methyl ester; Papaya fruit.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500006

Peptide synthesis: chemical or enzymatic
Provedor de dados: Electronic Journal of Biotechnology
Autores: Guzmán,Fanny; Barberis,Sonia; Illanes,Andrés.
Peptides are molecules of paramount importance in the fields of health care and nutrition. Several technologies for their production are now available, among which chemical and enzymatic synthesis are especially relevant. The present review pretends to establish a non-biased appreciation of the advantages, potentials, drawbacks and limitations of both technologies. Chemical synthesis is thoroughly reviewed and their potentials and limitations assessed, focusing on the different strategies and challenges for large-scale synthesis. Then, the enzymatic synthesis of peptides with proteolytic enzymes is reviewed considering medium, biocatalyst and substrate engineering, and recent advances and challenges in the field are analyzed. Even though chemical synthesis...
Tipo: Journal article
Palavras-chave: Enzymatic synthesis; Peptides; Proteases; Solid-phase synthesis.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200012

Potential use of Lactobacillus casei TISTR 1500 for the bioconversion from palmyra sap and oil palm sap to lactic acid
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chooklin,Supasit; Kaewsichan,Lupong; Kaewsrichan,Jasadee.
Lactic acid is a product that finds several applications in food, cosmetic, pharmaceutical and chemical industries. The main objective of this work is to evaluate potential use of the sap from palmyra (Borassus flabellifer Linn.) and oil palm (Elaeis guineensis) as substrate for lactic acid production by Lactobacillus casei TISTR 1500. The effects of acid hydrolysis, pH control and nutrient supplement of palmyra sap and oil palm sap on fermentation performance were investigated. It was found that lactic acid fermentation using palmyra sap was not significantly affected by either acid hydrolysis or pH control. The addition of MRS increased biomass and product yield. The final lactic acid concentration, dry cell weight and productivity were increased by...
Tipo: Journal article
Palavras-chave: Fermentation; Lactic acid; Lactobacillus casei TISTR 1500; Oil palm sap; Palmyra sap.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500010

Genetic diversity analysis of Bemisia tabaci populations in Pakistan using RAPD markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hameed,Saima; Hameed,Shahid; Sadia,Munazza; Malik,Salman A.
Background: The Bemisia tabaci is one of the most devastating pests of agricultural crops and ornamental plants worldwide. The genetic diversity and biotype status of the Bemisia tabaci in Pakistan was assessed by using random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). A total 80 samples of B. tabaci collected from 14 districts of the Punjab province and 7 districts of the Sindh province were included. Results: All 10 primers screened in this study generated 151 scorable amplification products, of which 117 or 77% were polymorphic. Pairwise Nei and Li’s similarity had ranged from 0.25 to 0.88 among all individuals analyzed. Based on Nei and Li’s similarity coefficients Bemisia populations were grouped into 3 main clusters and clearly...
Tipo: Journal article
Palavras-chave: Asia II 1; Genetic diversity; UPGMA; Whitefly.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600006

Production and stability studies of the bioemulsifier obtained from a new strain of Candida glabrata UCP 1002
Provedor de dados: Electronic Journal of Biotechnology
Autores: Asfora Sarubbo,Leonie; Moura de Luna,Juliana; de Campos-Takaki,Galba Maria.
Evaluation of both tenso-active and emulsifying activities indicated that a biosurfactant was produced by the newly isolated and promising strain Candida glabrata isolated from mangrove sediments. The extracellular water-soluble emulsifying agent was isolated and identified as a heteropolymer. The maximum of bioemulsifier production was observed when the strain was grown on soluble and insoluble substrates cotton seed oil plus glucose, reaching values of 10.0 g/l after 144 hrs at 200 rpm. The cell-free culture broth containing the examined agent lowered the surface tension of the medium to 31 mN/m. Stable and compact emulsions with emulsifying activity of 75% of cotton seed oil were detected. The emulsification capacity remained practically unaltered...
Tipo: Journal article
Palavras-chave: Biosurfactant; Candida; Emulsifier; Fermentation; Glucose; Vegetal oil.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400008

Assessment of toxicity of a biosurfactant from Candida sphaerica UCP 0995 cultivated with industrial residues in a bioreactor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bezerra de Souza Sobrinho,Humberto; de Luna,Juliana Moura; Rufino,Raquel Diniz; Figueiredo Porto,Ana Lúcia; Sarubbo,Leonie Asfora.
Background: The aim of the present study was to propose a low-cost method for the production of a biosurfactant by the yeast Candida sphaerica and assess its toxicity and phytotoxicity. The medium was formulated with distilled water supplemented with residue from a soy oil refinery (5%) and corn steep liquor (2.5%) as substrates. These two products were the sources of carbon and nitrogen as well as mineral elements to encourage the growth of the microorganism and production of a biosurfactant. Results: The isolated biosurfactant yield was 6.364 g/l. The biosurfactant exhibited an excellent ability to reduce surface tension (26 mN/m) and demonstrated no toxicity against seeds of Brassica oleracea, Chicoria intybus and Solanum gilo or the micro crustacean...
Tipo: Journal article
Palavras-chave: Biosurfactant; Bioreactor; Candida sphaerica; Industrial residues; Toxicity.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400004

The potential use of lipases in the production of fatty acid derivatives for the food and nutraceutical industries
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ferreira-Dias,Suzana; Sandoval,Georgina; Plou,Francisco; Valero,Francisco.
The potential of lipases (E.C.3.1.1.3.) as biocatalysts for the production of fatty acid derivatives for the food and nutraceutical industries, such as flavouring esters, fatty acid esters of antioxidants and structured lipids, is enormous, mainly due to their high regio- and stereo-selectivities, in addition to the other well-known advantages of enzymatic processes. The replacement of chemical catalysts by lipases presents great benefits in terms of the nutritional properties of the obtained products and environmental care. The reactions performed for the production of these compounds, as well as the best operation conditions, the biocatalysts used, reactor types and operation mode, are addressed in this review.
Tipo: Journal article
Palavras-chave: Fatty acids derivatives; Lipases; Nutraceutical industries.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300012

Biocontrol of root and crown rot in tomatoes under greenhouse conditions using Trichoderma harzianum and Paenibacillus lentimorbus: Additional effect of solarization
Provedor de dados: Electronic Journal of Biotechnology
Autores: Montealegre,Jaime R; Herrera,Rodrigo; Velásquez,Juan Carlos; Silva,Polyana; Besoaín,Ximena; Pérez,Luz María.
Trichoderma harzianum 650 (Th650) and Paenebacillus lentimorbus 629 (Pl629) selected earlier for their ability to control Rhizoctonia solani, Fusarium solani and F. oxysporum in vitro, were applied alone or combined with solarization (summer assay) and/or with methyl bromide (MeBr) (summer and winter assays) to a soil with a high inoculum level, for the control of tomato root rot caused by the complex F. oxysporum f. sp. lycopersici - Pyrenochaeta lycopersici - Rhizoctonia solani. Evaluations were also performed independently for root damage caused by P. lycopersici, and also for R. solani in the summer assay. MeBr decreased tomato root damage caused by the complex from 88.7% to 21.2% and from 78.4% to 35.7% in the summer and in the winter assay,...
Tipo: Journal article
Palavras-chave: Fusarium oxysporum; Lycopersicon esculentum; Pyrenochaeta lycopersici; Rhizoctonia solani; Solarization.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300004

Biotechnology, bioethics and the poor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bhardwaj,Minakshi.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300004

Biosorption of heavy metals by Talaromyces helicus: a trained fungus for copper and biphenyl detoxification
Provedor de dados: Electronic Journal of Biotechnology
Autores: Romero,M. Cristina; Reinoso,Enso H.; Urrutia,M. Inés; Moreno Kiernan,Alejandro.
At present, it is common to observe environments with organic and inorganic pollution, defined as co-contamination. Most industrial and urban effluents releases both pollutant types, leading to a complex environmental problem, as the biota must be tolerant to both xenobiotics. T. helicus, an efficient strain to degrade biphenyl, was trained with high copper levels, and became co tolerant to cobalt, lead and cadmium when was cultured in their presence. The copper adaptation was the result of physiological mechanisms, and the activated biochemical processes conferred resistance to Cu2+ as well as to other heavy metals. Furthermore, the Cu2+ adaptation of the mycelium was also transferred to the spores, that removed twice as much copper from solution than...
Tipo: Journal article
Palavras-chave: Biodegradation; Biphenyl; Cocontaminated sites; Cotolerance; Metal sorption; Talaromyces helicus.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300009

Kinetic study on inducibility of polygalacturonases from Aspergillus flavipes FP-500
Provedor de dados: Electronic Journal of Biotechnology
Autores: Martínez-Trujillo,Aurora; Aranda,Juan S; Aguilar-Osorio,Guillermo.
The aim of this work was to describe growth dynamics, substrate depletion and polygalacturonases production by Aspergillus flavipes FP-500 in batch cultures by means of unstructured models. The microorganism was cultivated on several mono- di- and poly- saccharides, and then the culture development modeled with Monod and Leudeking-Piret equations. The kinetic parameters related to the models (µmax, &amp;#947;x/s, &amp;#945; and &amp;#946;) were obtained by minimizing the quadratic residuals function with a simplex algorithm. An accurate description of experimental data was attained with the proposed models. Besides, modeling provided significant kinetic information on microbial degradation of complex substrates, such as the correlation between specific...
Tipo: Journal article
Palavras-chave: Constitutive enzymes; Inducible enzymes; Initial pH; Kinetic modeling; Pectinases.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400008

Optimization of polyethylenimine-mediated transient transfection using response surface methodology design
Provedor de dados: Electronic Journal of Biotechnology
Autores: Fang,Qiangyi; Shen,Bingqian.
Response surface methodology was undertaken to optimize the polyethylenimine-mediated transient transfection of suspension cultured HEK 293-F cells. A total of 15 combinations were designed according to Box-Behnken design to identify the effects of DNA concentration, polyethylenimine concentration and incubation time on transient transfection efficiency. The highest integral optic density of green fluorescent protein presenting r-protein yield was accessed using a DNA concentration of 1.75 µg/mL, a polyethylenimine concentration of 10.5 µg/mL, and an incubation time of 11.8 min. Analysis of variance demonstrated that the experimental values fit well with a quadratic model. The RSM-optimized transient transfection resulted in greater production of human...
Tipo: Journal article
Palavras-chave: Bioreactor; Human tissue kallikrein; Transient gene expression.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500010

Optimisation of the solids suspension conditions in a continuous stirred tank reactor for the biooxidation of refractory gold concentrates
Provedor de dados: Electronic Journal of Biotechnology
Autores: González,Ramón; Gentina,Juan C.; Acevedo,Fernando.
The large-scale biooxidation of gold concentrates is usually carried on in continuous stirred tank reactors (CSTR). Attaining homogeneous slurries is a difficult task, as solids tend to stratify in the tank. The objective of this work was to determine the optimal conditions of agitation in a CSTR so to obtain the best solids suspension. The experiments were performed in a 5 litre glass tank operated with 3 litres of 6% w/v slurry. The impellers (pitched blade turbine or marine propeller) were placed at heights of 6.7 to 13.4 cm from the bottom and operated at 370 to 1040 rpm, with specific aeration rates of 0.3 to 3.7 vvm. A statistical experimental design was used which allowed the derivation of a model representing response surfaces of the exit and mean...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300008

Assessment of genetic diversity and relationships among Osmanthus fragrans cultivars using AFLP markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yuan,Wang Jun; Han,Yuan Ji; Dong,Mei Fang; Shang,Fu De.
This study was conducted to reveal genetic diversity among 100 Osmanthus fragrans cultivars using amplified fragment length polymorphism (AFLP) markers. Eight AFLP primer combinations produced a total of 443 polymorphic fragments with an average of 64 per primer combination. The percentage of polymorphic bands (86.81%), the resolving power (Rp) (32.71) and the PIC values (0.331) showed the efficiency of used primer combinations. The revealed AFLP makers were effective in distinguishing all the cultivars considered. Cluster analysis were performed to assess patterns of diversity among cultivars and showed the abundant genetic diversity. The overall distribution pattern of molecular variation suggested that 93.33% of the total genetic variance was within the...
Tipo: Journal article
Palavras-chave: AFLP marker; Cluster analysis; Genetic diversity; Osmanthus fragrans.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100002

User-friendly optimization approach of fed-batch fermentation conditions for the production of iturin A using artificial neural networks and support vector machine
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chen,Fudi; Li,Hao; Xu,Zhihan; Hou,Shixia; Yang,Dazuo.
Background In the field of microbial fermentation technology, how to optimize the fermentation conditions is of great crucial for practical applications. Here, we use artificial neural networks (ANNs) and support vector machine (SVM) to offer a series of effective optimization methods for the production of iturin A. The concentration levels of asparagine (Asn), glutamic acid (Glu) and proline (Pro) (mg/L) were set as independent variables, while the iturin A titer (U/mL) was set as dependent variable. General regression neural network (GRNN), multilayer feed-forward neural networks (MLFNs) and the SVM were developed. Comparisons were made among different ANNs and the SVM. Results The GRNN has the lowest RMS error (457.88) and the shortest training time (1...
Tipo: Journal article
Palavras-chave: Artificial neural network; Fed-batch fermentation; General regression neural network; Iturin A; Support vector machine.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400003

Assessment of Grenada’s capacity to implement the Biosafety Protocol
Provedor de dados: Electronic Journal of Biotechnology
Autores: De Vere Pitt,James; Roberts,Dianne.
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200002

Evaluation of two bioadsorbents for removing paracetamol from aqueous media
Provedor de dados: Electronic Journal of Biotechnology
Autores: Flores Nardy Ribeiro,Araceli Verónica; Belisário,Marciela; Moretto Galazzi,Rodrigo; Cazoni Balthazar,Daniele; Godoi Pereira,Madson de; Nardy Ribeiro,Joselito.
The frequent contamination of water resources with drugs comprises one the most important environmental problems. In order to avoid serious disturbances for aquatic life, efficient and economically viable procedures should be developed for removing common pollutants, as paracetamol. From these considerations, the present work evaluated the efficiency of sugar cane bagasse (SCB) and vegetable sponge (VS), two natural adsorbents commonly found in Brazil, for retaining paracetamol molecules dispersed in aqueous solutions. Thus, systems composed of glass columns and peristaltic pumps were optimized and, for pH, the best value was 7.0. After optimisation, adsorption isotherms were built and it was possible to calculate the MAC F values for SCB (120.5 µg/g) and...
Tipo: Journal article
Palavras-chave: Adsorption; Bioadsorbent; Paracetamol; Water.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600007

Novel technique for microbial production of 3,4-Dihydroxy Phenyl L-alanine by a mutant strain of Aspergillus oryzae
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ali,Sikander; ul-Haq,Ikram; Qadeer,M.A.
L-DOPA is a useful drug for Parkinson’s disease. This investigation deals with the biosynthesis of L-DOPA by parental (GCB-6) and mutant (UV-7) strains of Aspergillus oryzae. There was a marked difference between the mycelial morphology and pellet type of the parental and UV-irradiated mutant cultures. The mutant strain of Aspergillus oryzae UV-6 showed pellet-like mycelial morphology and improved tyrosinase activity. Mould mycelium was used for biochemical conversion of L-tyrosine to L-DOPA since tyrosinase is an intracellular enzyme. The mutant was found to give 3.72 folds higher production of L-DOPA than the parental strain. The comparison of kinetic parameters was also done which showed greater ability of the mutant to yield L-DOPA (i.e. Yp/x 32.73...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200006

NaCl effects in Zea mays L. x Tripsacum dactyloides (L.) L. hybrid calli and plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pesqueira,Julieta; García,Maria Dina; Staltari,Sebastian; Molina,Maria del Carmen.
High salt concentrations in soils negatively affect maize growth. Techniques such as remote hybridization and in vitro selection have been extensively used to accelerate breeding processes. In order to determine the usefulness of Tripsacum to improve salt tolerance in maize, the effects of NaCl, in vitro and in vivo, were evaluated in an intergeneric hybrid (MT) obtained from crossing Zea mays with Tripsacum dactyloides. Organogenic calli, induced from immature MT hybrid embryos, were exposed to different NaCl concentrations and the survival and regeneration percentages were calculated. Plants of the MT hybrid, obtained from the organogenic calli, were exposed to NaCl concentrations considered harmful for maize. The shoot dry weights of plants exposed to...
Tipo: Journal article
Palavras-chave: Intergeneric hybrid; Plant regeneration; Organogenesis; Salinity tolerance.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300022

DNA from tissues of young mice is optimal for genotyping
Provedor de dados: Electronic Journal of Biotechnology
Autores: Picazo,María G; García-Olmo,Dolores C.
Background Genotyping of mice is a common procedure in animal facilities. The aim of this study was to compare the quantity and quality of DNA extracted from samples obtained from young mice (YM; 10 d old) and adult mice (AM; 12 weeks old). We collected samples from the tail and ear of YM and AM. We also sampled blood, check cells (via buccal swabs), hair and fecal pellets of AM, and biopsied distal phalanx of YM. We isolated DNA using commercial kits and determined concentrations and purity by spectrophotometry. The integrity of DNA was evaluated by agarose-gel electrophoresis and polymerase chain reaction (PCR). Results DNA in all samples was amplified successfully but the intensities of bands after electrophoresis was heterogeneous. In general, tissues...
Tipo: Journal article
Palavras-chave: DNA extraction; Genotyping; Mouse.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000200004

A new variety of Bacopa monnieri obtained by in vitro polyploidization
Provedor de dados: Electronic Journal of Biotechnology
Autores: Salvio Escandón,Alejandro; Hagiwara,Juan Carlos; Alderete,Liliana Marisol.
The commercial value of Bacopa monnieri, a widespread herbaceous plant in Argentina, can be substantially improved increasing its flower size by chromosome doubling with colchicine. MS supplemented with 0.25 mg/L of 6-benzylaminopurine proved to be an appropriate medium for the in vitro multiplication of nodal segments of B. monnieri. Polyploidization was achieved submerging nodal segments during 24 or 48 hrs in colchicine solution 0.001 and 0.01% P/V, in 1% DMSO. Segments submerged in water and in DMSO 1% aqueous solution were used as controls. DNA contents from recovered plants was measured and characterized and their phenotype described. Two tetraploid plants originated from independent events were detected. These plants showed significant differences...
Tipo: Journal article
Palavras-chave: Colchicine; Flow cytometry; Ornamental plants; Scrophulariaceae; Tetraploid.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300002

Prolyl endopeptidase - Optimization of medium and culture conditions for enhanced production by Lactobacillus acidophilus
Provedor de dados: Electronic Journal of Biotechnology
Autores: Brzozowski,Bartosz; Lewandowska,Malgorzata.
Background Lactic acid bacteria are able to reduce the immunoreactivity of proteins of cereal grains during wheat dough fermentation or may be a source of proteolytic preparations added during bread making. The key enzyme in prolamin degradation is prolyl endopeptidase. This study was aimed at optimizing the composition of a culture medium and culture conditions that would enhance the synthesis of intracellular prolyl endopeptidase (PEP) by Lactobacillus acidophilus 5e2. Results The application of Plackett-Burman screening plans enabled demonstrating that the concentration of a nitrogen source in the culture and the initial pH value of the culture medium were significant for PEP synthesis. Further optimization conducted with the method of central composite...
Tipo: Journal article
Palavras-chave: Central composite design; Plackett-Burman design; Response surface methodology.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000500003

Analysis of genetic diversity and differentiation of sheep populations in Jordan
Provedor de dados: Electronic Journal of Biotechnology
Autores: Al-Atiyat,Raed Mahmoud; Salameh,Naser M; Tabbaa,Mohammad J.
Background Genetic diversity of sheep in Jordan was investigated using microsatellite markers (MS). Six ovine and bovine MS located on chromosomes 2 and 6 of sheep genome were genotyped on 294 individual from ten geographical regions. Results The number of alleles per locus (A), the expected heterozygosity (He) and observed heterozygosity (Ho) were measured. Overall A, He and Ho were 12.67, 0.820 and 0.684, respectively. On the other hand, genetic distances undoubtedly revealed the expected degree of differentiation among the studied populations. The finding showed closeness of three populations from south (Maan, Showbak and Tafeilah) to each other. Populations from the middle regions of Jordan (Karak, Madaba, Amman, AzZarqa and Mafraq) were found to be in...
Tipo: Journal article
Palavras-chave: Awassi sheep; DNA microsatellite; Genetic diversity and differentiation.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000400005

Plant-antivenom: Database of anti-venom medicinal plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Amui,Saulo França; Puga,Renato David; Soares,Andreimar Martins; Giuliatti,Silvana.
Plant-antivenom is a computational Websystem about medicinal plants with anti-venom properties. The system consists of a database of these plants, including scientific publications on this subject and amino acid sequences of active principles from venomous animals. The system relates these data allowing their integration through different search applications. For the development of the system, the first surveys were conducted in scientific literature, allowing the creation of a publication database in a library for reading and user interaction. Then, classes of categories were created, allowing the use of tags and the organization of content. This database on medicinal plants has information such as family, species, isolated compounds, activity, inhibited...
Tipo: Journal article
Palavras-chave: Animal venoms; Natural plant inhibitors; Web system.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100006

Isolation of high-quality RNA from Platycladus orientalis and other Cupressaceae plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chang,Ermei; Zhao,Yuxin; Wei,Qianchun; Shi,Shengqing; Jiang,Zeping.
Platycladus orientalis has a lifespan of several thousand years in China, making it a good plant in which to study aging at the molecular level, but this requires sufficient quantities of high-quality P. orientalis RNA. However, no appropriate methods have been reported for total RNA isolation from P. orientalis leaves. The TRIzol method did not extract RNA, while cetyltrimethylammonium bromide, sodium dodecyl sulfate-phenol, and plant RNAout kit (Tianz, Inc., China) protocols resulted in low yields of poor quality RNA. Isolating total RNA using the Spectrum™ Plant Total RNA Kit (Sigma-Aldrich, St. Louis, MO, USA) resulted in a high-quality product but a low yield. However, the two-step removal of polyphenols and polysaccharides in the improved plant...
Tipo: Journal article
Palavras-chave: Cupressaceae plants; Polysaccharides; Polyphenols; Total RNA isolation; Two-step removal of polyphenols and polysaccharides.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500004

Inhibition of shrimp pathogenic vibrios by extracellular compounds from a proteolytic bacterium Pseudomonas sp. W3
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rattanachuay,Pattamarat; Kantachote,Duangporn; Tantirungkij,Manee; Nitoda,Teruhiko; Kanzaki,Hiroshi.
Pseudomonas sp. W3, a bacterium known to produce an extracellular alkaline protease, secreted secondary metabolites that inhibited pathogenic bacteria responsible for shrimp luminous vibriosis disease. Antivibrio compounds in the culture supernatant or culture filtrates (0.45 µm and 0.22 µm) of the isolate W3 were tested using an agar well diffusion method on a number of pathogenic vibrios. Vibrio harveyi PSU 2015 a pathogenic isolate was the most sensitive strain. The effectiveness of preparations from the isolate W3 against V. harveyi PSU 2015, and V. cholerae PSSCMI 0062 was in the order of culture supernatant &gt; 0.45 µm culture filtrate &gt; 0.22 µm culture filtrate. These extracellular antivibrio compounds also lysed both dead and living cells of V....
Tipo: Journal article
Palavras-chave: Bacteriolytic enzymes; Bioactive compounds; Pseudomonas sp. W3; Shrimp pathogenic bacteria; Vibrio spp.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100008

Using Bcl-xL anti-apoptotic protein for altering target cell apoptosis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Iz,Sultan Gülçe; Çalimlioglu,Beste; Gürhan,Saime Ismet Deliloglu.
Background: Altering target cell apoptosis is one of the challenging ideas of biotechnological applications. There are several applications of over expressing Bcl-xL anti-apoptotic protein from recombinant protein production to DNA vaccination strategies. The aim of the present study is to evaluate the anti-apoptotic efficacy of Bcl-xL expressing dual promoter plasmid system as a candidate to be used for recombinant protein production and DNA vaccination approaches. For this purpose, Bcl-xL anti-apoptotic protein gene was inserted in a dual expressing vector system in frame with EGFP (enhanced green fluorescence protein) after IRES (internal ribosomal site). The plasmid has a multiple cloning site after CMV (cytomegalovirus promoter) left empty to be...
Tipo: Journal article
Palavras-chave: Animal cell biotechnology; Apoptosis; Bcl-xL anti-apoptotic protein.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500002

Construction of a eukaryotic expression vector for pEGFP-FST and its biological activity in duck myoblasts
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Xinxin; Wang,Jiwen; Liu,Hehe; Wang,Haohan; Sun,Lingli; Yang,Chao; Li,Liang; Zheng,Yi.
Background Follistatin (FST), a secreted glycoprotein, is intrinsically linked to muscle hypertrophy. To explore the function of duck FST in myoblast proliferation and differentiation, the pEGFP-FST eukaryotic expression vector was constructed and identified. The biological activities of this vector were analyzed by transfecting pEGFP-FST into cultured duck myoblasts using Lipofectamine™ 2000 and subsequently determining the mRNA expression profiles of FST and myostatin (MSTN). Results The duck pEGFP-FST vector was successfully constructed and was confirmed to have high liposome-mediated transfection efficiency in duck myoblasts. Additionally, myoblasts transfected with pEGFP-FST had a higher biological activity. Significantly, the overexpression of FST in...
Tipo: Journal article
Palavras-chave: Follistatin; Muscle hypertrophy; Overexpression; Transfection efficiency.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000500006

Protein interactions in enzymatic processes in textiles
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tzanov,Tzanko; Andreaus,Jürgen; Guebitz,Georg; Cavaco-Paulo,Artur.
Enzymes are the catalysts of all reactions in living systems. These reactions are catalysed in the active sites of globular proteins. The proteins are composed by amino acids with a variety of side chains ranging from non-polar aliphatic and aromatic to acidic, basic and neutral polar. This fact allows to a globular 3D protein to create in the active site all ranges of microenvironments for catalysis. Major advances in microbial technology and genetics allow recently the broad range of enzymatic applications in the industry. Enzymatic processes have been increasingly incorporated in textiles over the last years. Cotton, wool, flax or starches are natural materials used in textiles that can be processed with enzymes. Enzymes have been used for desizing,...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300013

Normalization of elevated liver enzymes due to V-1 Immunitor therapy
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jirathitikal,Vichai; Metadilogkul,Orapun; Bourinbaiar,Aldar S.
V-1 Immunitor (V1) is an oral AIDS vaccine currently being used as a therapeutic modality by HIV-positive patients. Upon interim analysis of phase I safety trial it has been discovered that patients who had elevated liver enzymes aspartate (AST/SGOT) and alanine (ALT/SGPT) aminotransferases have experienced the reduction of enzyme levels back to normal. Two other hepatitis markers alkaline phosphatase and bilirubin have also decreased. V1’s effect may be hepatitis-specific since liver enzymes in normal patients treated with V1 have not changed and three patients who were Hepatitis B antigen positive at baseline became negative after therapy. The results suggest that V1 supplementation reduces hepatic damage caused by hepatitis viral infection.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000100010

Over-expression of Mycobacterium neoaurum 3-ketosteroid-&amp;#8710;1-dehydrogenase in Corynebacterium crenatum for efficient bioconversion of 4-androstene-3,17-dione to androst-1,4-diene-3,17-dione
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhang,Xian; Wu,Dan; Yang,Taowei; Xu,Meijuan; Rao,Zhiming.
Background: 3-Ketosteroid-&amp;#8710;¹-dehydrogenase (KSDD), a flavoprotein enzyme, catalyzes the bioconversion of 4-androstene-3,17-dione (AD) to androst-1,4-diene-3,17-dione (ADD). To date, there has been no report about characterization of KSDD from Mycobacterium neoaurum strains, which were usually employed to produce AD or ADD by fermentation. Results: In this work, Corynebacterium crenatum was chosen asa new host for heterologous expression of KSDD from M. neoaurum JC-12 after codon optimization of the KSDD gene. SDS-PAGE and western blotting results indicated that the recombinant C. crenatum harboring the optimized ksdd (ksdd n) gene showed significantly improved ability to express KSDD. The expression level of KSDD was about 1.6-fold increased C....
Tipo: Journal article
Palavras-chave: Androst-1; 4-diene-3; 17-dione Bioconversion Codon optimization Flavoprotein enzyme Heterologous expression Mycobacterium neoaurum Overexpression Recombinant Corynebacterium Sterol catabolism Whole-cell catalyst.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600013

Influence of initial pH of the growing medium on the activity, production and genes expression profiles of laccase of Pleurotus ostreatus in submerged fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Díaz,Rubén; Téllez-Téllez,Maura; Sánchez,Carmen; Bibbins-Martínez,Martha D; Díaz-Godínez,Gerardo; Soriano-Santos,Jorge.
Background: Enzymatic activity and laccase isoenzymes number of Pleurotus ostreatus grown in different pH values of the growing medium in submerged fermentation and incubated in buffer solutions of different initial pH values were determined. The expression profiles of five laccase genes (Lacc1, Lacc4, Lacc6, Lacc9 and Lacc10) in these cultures were also studied. Results: The highest laccases activity was obtained in cultures grown at initial pH of 4.5 and the lowest in cultures grown at initial pH of 8.5. Isoenzyme profiles were different in all the cases. Lacc1, Lacc4, Lacc6 and Lacc10 were expressed in all the cultures. Conclusions: The initial pH of the growing medium is an important factor for regulating the expression of laccase genes, having an...
Tipo: Journal article
Palavras-chave: Laccases; Pleurotus ostreatus; Submerged fermentation; Zymogram.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400006

Production of &amp;#946;-glucosidase on solid-state fermentation by Lichtheimia ramosa in agroindustrial residues: Characterization and catalytic properties of the enzymatic extract
Provedor de dados: Electronic Journal of Biotechnology
Autores: Garcia,Nayara Fernanda Lisboa; Santos,Flávia Regina da Silva; Gonçalves,Fabiano Avelino; Paz,Marcelo Fossa da; Fonseca,Gustavo Graciano; Leite,Rodrigo Simões Ribeiro.
Background &amp;#946;-Glucosidases catalyze the hydrolysis of cellobiose and cellodextrins, releasing glucose as the main product. This enzyme is used in the food, pharmaceutical, and biofuel industries. The aim of this work is to improve the &amp;#946;-glucosidase production by the fungus Lichtheimia ramosa by solid-state fermentation (SSF) using various agroindustrial residues and to evaluate the catalytic properties of this enzyme. Results A high production of &amp;#946;-glucosidase, about 274 U/g of dry substrate (or 27.4 U/mL), was obtained by cultivating the fungus on wheat bran with 65% of initial substrate moisture, at 96 h of incubation at 35°C. The enzymatic extract also exhibited carboxymethylcellulase (CMCase), xylanase, and...
Tipo: Journal article
Palavras-chave: Cellobiase; Cellulases and hemicellulases; Industrial enzymes; Microbial enzymes.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400010

Simultaneous environmental manipulations in semi-perfusion cultures of CHO cells producing rh-tPA
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vergara,Mauricio; Becerra,Silvana; Díaz-Barrera,Alvaro; Berrios,Julio; Altamirano,Claudia.
We evaluated the combined effect of decreasing the temperature to a mild hypothermia range (34 and 31ºC) and switching to a slowly metabolizable carbon source (glucose substituted by galactose) on the growth and production of a recombinant human tissue plasminogen activator (rh-tPA) by Chinese hamster ovary cells in batch and semi-perfusion cultures. In batch cultures using glucose as a carbon source, decreasing the temperature caused a reduction in cell growth and an increase in specific productivity of rh-tPA of 32% at 34ºC and 55% at 31ºC, compared to cultures at 37ºC. Similar behaviour was observed in cultures at 34ºC using galactose as a carbon source. Nonetheless, at 31ºC, the specific productivity of rh-tPA strongly decreased (about 58%) compared to...
Tipo: Journal article
Palavras-chave: CHO cells; Galactose; Glutamate; Low temperature; Perfusion culture; Rh-tPA.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600002

Molecular characterization and transcriptome profiling of expansin genes isolated from Calotropis procera fibers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cheema,Hafiza Masooma Naseer; Bashir,Aftab; Khatoon,Asia; Iqbal,Nadia; Zafar,Yusuf; Malik,Kauser A.
The Calotropis procera seed fibers provide an excellent model system to study the genes involved in fiber elongation, fineness and strength. Expansins constitute one of the important gene families involved in plant cell expansion and other cell wall modification processes. Four homologs of Expansin A gene i.e. CpEXPA1, CpEXPA2, CpEXPA3 and CpEXPA4 were isolated from the cDNA library obtained from fast growing Calotropis procera fibers. These homologs represented typical Expansin A family. Each of them had two conserved domains including GH45 like domain and the putative polysaccharide binding domain. The deduced amino acid sequences of the homologs indicated three conserved motifs: i) eight cysteine residues at N-terminus, ii) four tryptophan residues at...
Tipo: Journal article
Palavras-chave: Calotropis procera; CDNA library; Cotton fibers; EXPANSIN A; Signal peptide; Transcriptome profiling.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600010

Transient gene expression in secondary somatic embryos from coffee tissues electroporated with the genes gus and bar
Provedor de dados: Electronic Journal of Biotechnology
Autores: Da Silva,Rafael Fernandez; Menéndez-Yuffá,Andrea.
Different electroporation conditions were evaluated, toward the goal of transformation of Coffea arabica cv. Catimor. The tissues assayed were: embryogenic calli, leaf sections from in vitro plants, and somatic embryos in globular and torpedo stage obtained from cell suspensions. The effect of 1 or 24-hour pretreatment with an enzymatic solution (2% cellulase, 1% macerozyme) and electric field strength (375, 625, 875 V/cm) was evaluated. In all the experiments the tissues were incubated in ASP buffer (potassium aspartate) during three hours, and then one hour with plasmid DNA (pCambia3201, containing gus and bar genes) at room temperature. The electroporation was performed at a capacitance of 900 &amp;#956;F. The effect of the parameters evaluated was...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000100006

Inhibitor tolerance and flocculation of a yeast strain suitable for second generation bioethanol production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Westman,Johan O; Taherzadeh,Mohammad J; Franzén,Carl Johan.
Background: Robust second generation bioethanol processes require microorganisms able to ferment inhibitory lignocellullosic hydrolysates. In this study, the inhibitor tolerance and flocculation characteristics of Saccharomyces cerevisiae CCUG53310 were evaluated in comparison with S. cerevisiae CBS8066. Results: The flocculating strain CCUG53310 could rapidly ferment all hexoses in dilute acid spruce hydrolysate, while CBS8066 was strongly inhibited in this medium. In synthetic inhibitory media, CCUG53310 was more tolerant to carboxylic acids and furan aldehydes, but more sensitive than CBS8066 to phenolic compounds. Despite the higher tolerance, the increase in expression of the YAP1, ATR1 and FLR1 genes, known to confer resistance to...
Tipo: Journal article
Palavras-chave: Biofuel; Furfural; Lignocellulose; Phenolic inhibitors; Saccharomyces cerevisiae.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000300005

Enhancement with inducers of lacasse production by some strains and application of enzyme to dechlorination of 2,4,5-trichlorophenol
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gedikli,Serap; Aytar,Pinar; Ünal,Arzu; Yamaç,Mustafa; Çabuk,Ahmet; Kolankaya,Nazif.
Lacasse is one of the extracellular enzymes excreted from white and brown rot fungi, which is involved in ligninolysis. In the present study, the effects of the addition of lacasse inducers to the medium on enhancement of enzyme production under conditions of submerged fermentation were researched. At first, a culture medium was selected suitable for lacasse production. To increase the production of lacasse using different inducers and to examine the ability of dechlorination, this article focuses on screen lacasse activity of 21 basidiomycetes isolates grown in five culture media. All inducers evaluated influenced lacasse activity positively except for gallic acid, mannitol, and malt extract for studied isolates. Our findings showed that lacasse activity...
Tipo: Journal article
Palavras-chave: 2; 4; 5-trichlorophenol basidiomycetes dechlorination inducer lacasse.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600006

Microbial-induced remediation of Zn2+ pollution based on the capture and utilization of carbon dioxide
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhan,Qiwei; Qian,Chunxiang.
Background: Microbial-induced remediation of Zn2+ pollution based on the capture and utilization of carbon dioxide was investigated. In this study, carbon dioxide was absorbed and transformed into carbonate ions under the enzymatic action of Paenibacillus mucilaginosus, which was being utilized to mineralize Zn2+. Results: The compositional and morphological properties of the precipitations were studied using Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The thermal properties of the precipitates were investigated by thermogravimetric-differential scanning calorimetry (TG-DSC). The FTIR results confirmed that the functional groups of the...
Tipo: Journal article
Palavras-chave: Carbon dioxide; Microbial-induced; Mineralization; Paenibacillus mucilaginosus; Remediation.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000100005

mRNA transcription and protein expression of PPAR&amp;#947;, FAS, and HSL in different parts of the carcass between fat-tailed and thin-tailed sheep
Provedor de dados: Electronic Journal of Biotechnology
Autores: Xu,Xiaochun; Wei,Xuan; Yang,Yuxin; Niu,Wenzhi; Kou,Qifang; Wang,Xiaolong; Chen,Yulin.
Background The objective of this study was to compare the level differences of mRNA transcription and protein expression of PPAR&amp;#947;, FAS and HSL in different parts of the carcass in different tail-type sheep. Six Tan sheep and six Shaanbei fine-wool sheep aged 9 months were slaughtered and samples were collected from the tail adipose, subcutaneous adipose, and longissimus dorsi muscle. The levels of mRNA transcription and protein expression of the target genes in these tissues were determined by real-time quantitative PCR and western blot analyses. Results The results showed that PPAR&amp;#947;, FAS, and HSL were expressed with spatial differences in tail adipose, subcutaneous adipose and longissimus dorsi muscle of Tan sheep and Shaanbei fine-wool...
Tipo: Journal article
Palavras-chave: Genes; Difference; Tissues; Ovis.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300012

Diversity of bacterial communities in acid mine drainage from the Shen-bu copper mine, Gansu province, China
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yang,Yu; Shi,Wuyang; Wan,Minxi; Zhang,Yanfei; Zou,Lihong; Huang,Jufang; Qiu,Guanzhou; Liu,Xueduan.
This study presents bacterial population analyses of microbial communities inhabiting three sites of acid mine drainage (AMD) in the Shen-bu copper mine, Gansu Province, China. These sites were located next to acid-leached chalcopyrite slagheaps that had been abandoned since 1995. The pH values of these samples with high concentrations of metals ranged from 2.0 to 3.5. Amplified ribosomal DNA restriction analysis (ARDRA) was used to characterize the bacterial population by amplifying the 16S rRNA gene of microorganisms. A total of 39 operational taxonomic units (OTUs) were obtained from the three samples and sequenced from 384 clones. Sequence data and phylogenetic analyses showed that two dominant clones (JYC-1B, JYC-1D) in sample JYC-1 represented 69.5%...
Tipo: Journal article
Palavras-chave: Acid mine drainage; Amplified ribosomal DNA restriction analysis; Microbial communities.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100001

Production of antibody fragment (Fab) throughout Escherichia coli fed-batch fermentation process: Changes in titre, location and form of product
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jalalirad,Reza.
Background: Recombinant proteins, including antibodies and antibody fragments, often contain disulfide bond bridges that are necessary for their folding, stability and function. Production of disulfide-bond-containing proteins in the periplasm of Escherichia coli has been very useful, due to unique characteristics of the periplasm, for obtaining fully active and correctly folded products and for alleviating downstream processing. Results: In this study, fed-batch cultivation of Escherichia coli (E. coli) for production of Fab D1.3, which is an anti-hen egg white lysozyme (HEWL) antibody fragment was carried out at 37ºC, and the bacterial cells were induced by adding 0.1 mM IPTG to the culture medium. Fermentor was sampled over the course of fermentation;...
Tipo: Journal article
Palavras-chave: Antibody fragment; Cell disruption; Escherichia coli; Fed-batch fermentation; Periplasmic expression; Recombinant protein.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300009

Management of appropriate agricultural biotechnology for small producers: case study - Ecuador
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wendt,Jan; Izquierdo,Juan.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000100002

Use of Aspergillus niger in the bioleaching of colemanite for the production of boric acid
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bayat,Oktay; Arslan,Volkan; Bayat,Belgin.
Colemanite is one of the most important underground riches of Turkey, having approximately 60% of the world boron deposits, and it has a large portion in the deposits. In this study, chemical leaching and biological leaching methods were used for production of boric acid from colemanite (2CaO Â· 3B3O3 Â· 5H2O) (Emet-KÃ¼tahya, Turkey). Oxalic acid concentration, temperature, stirring time and solid-to-liquid ratio were taken as parameters in the chemical leaching process. It was found that the dissolution rate increases with increasing oxalic acid concentration and temperature but it decreases at higher solid-to-liquid ratios in the chemical leaching process. Using optimum conditions (d100 = 0.075 mm; 5% solids by weight; 0.55 M oxalic acid; 80 Â± 2ÂºC...
Tipo: Journal article
Palavras-chave: Aspergillus niger; Bioleaching; Boric acid; Chemical leaching; Colemanite; Oxalic acid.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300007

Rooting in Km selective media as efficient in vitro selection method for sunflower genetic transformation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Radonic,Laura Mabel; Zimmermann,Julián Marcos; Zavallo,Diego; López,Nilda; López Bilbao,Marisa.
Despite of numerous publications in sunflower genetic transformation, there is no efficient or reproducible protocol with low number of escapes. The latter would indicate that the selection method is not effective. In this work we used Km as selective agent, Agrobacterium tumefaciens EHA105 strain and a vector with the nptII gene under the nos promoter and uidA gene under 35S promoter. The response of agroinfected (A) and control (C) explants during the in vitro culture was studied and in both cases in presence or absence of Km in order to assign a differential morphologic response between transformed and non-transformed plants. The characteristics analyzed were: height, colour/aspect of the plantlets, in vitro rooting and in vitro bud-flower development....
Tipo: Journal article
Palavras-chave: Genetic transformation; Kanamycin; Selection; Sunflower.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300027

Isolation and characterization of hydrocarbon producing green alga Botryococcus braunii from Indian freshwater bodies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Dayananda,Chandrappa; Sarada,Ravi; Kumar,Vinod; Ravishankar,Gokare Aswathanarayana.
Samples of green colonial unicellular microalga Botryococcus braunii were collected from Bear Shola Falls at Kodaikanal (latitude 10.31 N and longitude 77.32 E), Tamil Nadu, India. Specimens were isolated, cultured and examined for its hydrocarbon content, morphological features and DNA structural resemblance with the known strain to confirm its identity. Inter simple sequence repeats (ISSR) finger printing revealed strong genetic similarity among the authentic strain (B. braunii N-836) and the Indian isolated strain (B. braunii CFTRI- Bb1) from Kodaikanal. The type of hydrocarbons produced by the Kodaikanal isolates were analyzed and identified as saturated hydrocarbons in the range of C21 to C33 by GCMS. Tetracosane and octacosane were found as the major...
Tipo: Journal article
Palavras-chave: Biomass; Carbon dioxide; Carotenoids; Fatty acids; Inter simple sequence repeats; Saturated hydrocarbons.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100008

Isolation and analysis of differentially expressed genes from peanut in response to challenge with Ralstonia solanacearum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ding,Yu Fei; Wang,Chuan Tang; Tang,Yue Yi; Wang,Xiu Zhen; Wu,Qi; Hu,Dong Qing; Yu,Hong Tao; Zhang,Jian Cheng; Cui,Feng Gao; Song,Guo Sheng; Gao,Hua Yuan; Yu,Shan Lin.
Background: Bacterial wilt caused by Ralstonia solanacearum is the most devastating disease in peanut. Planting resistant peanut cultivars is deemed as the sole economically viable means for effective control of the disease. To understand the molecular mechanism underlying resistance and facilitate breeding process, differences in gene expression between seeds of Rihua 1 (a Virginia type peanut variety resistant to bacterial wilt) inoculated with the bacterial pathogen suspension (10(9) cfu ml-1) and seeds of the same cultivar treated with water (control), were studied using the GenefishingTM technology. Results: A total of 25 differentially expressed genes were isolated. Expression of genes encoding cyclophilin and ADP-ribosylation factor, respectively,...
Tipo: Journal article
Palavras-chave: Arachis hypogaea; ARF; Cyclophilin; Differentially expressed genes; Genefishing; Ralstonia solanacearum.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500001

Immobilization and stabilization of papain on chelating sepharose: a metal chelate regenerable carrier
Provedor de dados: Electronic Journal of Biotechnology
Autores: Afaq,Sarah; Iqbal,Jawaid.
A method for immobilization of papain has been selected based on the interaction between its histidine, cysteine and tryptophan residues with the immobilized metal ion (IMI) carrier for maximum binding on a small volume of the carrier. The immobilized papain retained high activity has improved thermal stability and the carrier could be recovered from the spent bound enzyme, to be reused. Reimmobilization of papain on the regenerated matrix was equally effective with the retention of maximum enzyme activity.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300006

Biotechnology Issues in Africa
Provedor de dados: Electronic Journal of Biotechnology
Autores: Egwang,Thomas G.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300005

Isolation by PCR-based methods of a plant antifungal polygalacturonase-inhibiting protein gene
Provedor de dados: Electronic Journal of Biotechnology
A polygalacturonase-inhibiting protein (pgip) gene from Malus domestica cv Granny Smith apple fruit was cloned by degenerate oligo-primed polymerase chain reaction (PCR) and Inverse PCR. An alignment of the pear and bean PGIP sequences was used to design degenerate PCR primers in highly conserved regions. Degenerate PCR allowed the amplification of a 351bp internal fragment of the pgip gene, termed ipgip. The DNA sequence of ipgip was used to design Inverse PCR primers. A Southern blot of apple genomic DNA probed with the ipgip fragment was used to identify restriction enzyme sites for Inverse PCR. Inverse PCR enabled cloning of the remainder of the gene, from which a composite pgip gene sequence was constructed. A new set of PCR primers were designed to...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000300004

Normalized embryoid cDNA library of oil palm (Elaeis guineensis)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chan,Pek-Lan; Ma,Lay-Sun; Low,Eng-Ti L; Shariff,Elyana M; Ooi,Leslie Cheng-Li; Cheah,Suan-Choo; Singh,Rajinder.
A normalized embryoid cDNA library (EON) was constructed based on reassociation kinetics reaction. Results from dot blot hybridization and sequencing of EON cDNA clones clearly indicated that the normalization process reduced the frequency of high abundance transcripts and increased the frequency of low abundance gene transcripts. A total of 553 non-redundant expressed sequence tags (ESTs) were identified, 325 of these were not observed in the standard oil palm cDNA libraries sequenced previously. A total of 10 EON cDNA clones were chosen for expression profiling across samples from different stages of the tissue culture process. Two of the genes exhibited promising expression patterns for predicting the embryogenic potential in callus. Some of these genes...
Tipo: Journal article
Palavras-chave: Auxin; Expressed sequence tags; Gene expression; Low abundance genes; Tissue culture.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100010

Cloning and analysis of a NBS-LRR disease resistance gene candidate PnAG1 from peanut (Arachis hypogaea L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Shan,Shi-hua; Zhang,Ting-ting; Li,Chun-juan; Yang,Chen; Yan,Cai-xia; Wan,Shu-bo.
Background: Based on the conserved sequences of a known NBS resistance gene, a pair of degenerate primers was designed to amplify the NBS-LRR resistance gene from peanut using PCR and RACE methods. Results: Analyzing the amino acid sequence by BLAST on NCBI, which was deduced from the 1088bp-long gene named PnAG1-2, showed that it had a certain homology with some resistance proteins, among which Arachis cardenasii resistance protein gene had the highest homology (66%). Relative quantification PCR analysis indicated that PnAG1-2 gene expresses more in J11 (an A. flavus-resistant variety) than in JH1012 (an A. flavus-susceptible variety) when the harvest time was coming. Conclusions: In this study, the NBS-LRR resistance sequence was successfully cloned from...
Tipo: Journal article
Palavras-chave: Bioinformatics; NBS-LRR; Peanut; Real-time fluorescence quantitative PCR.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600006

Extending shelf life of fresh minced camel meat at ambient temperature by Lactobacillus dlbrueckii subsp. delbrueckii
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kalalou,Ichraq; Faid,Mohamed; Touhami Ahami,Ahmed.
Studies were conducted to stabilize minced meat by fermentation using mixed lactic acid bacteria cultures isolated from natural fermented foodstuffs and selected for their antimicrobial activity against some hazardous microorganisms. Fresh meat of camel purchased from the slaughterhouse of Rabat (Morocco) was minced separately with a meat mincer and supplied with 5% glucose, then inoculated with lactic acid bacteria. Microbiological analyses were carried out to determine standard plate count (SPC), staphylococci, coliforms, enterococci, and lactic acid bacteria. All analyses were determined after 1, 2, 3, 4 and 7 days during the storage. Results showed that a low pH of 4.0-4.2 can be achieved (within 3 days at 22&amp;ordm;C), with a drastic reduction in...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300005

Protein engineering of delta-endotoxins of Bacillus thuringiensis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Saraswathy,Nachimuthu; Kumar,Polumetla Ananda.
Bacillus thuringiensis (Bt) is a valuable environment-friendly biopesticide, which occupies 90% of the world biopesticide market. Its insecticidal properties are attributed to the presence of &lt;FONT FACE=Symbol&gt;d-&lt;/FONT&gt;endotoxins which are synthesized during the sporulation phase of the bacterium. &lt;FONT FACE=Symbol&gt;d-&lt;/FONT&gt;endotoxin or crystal toxin is a multi-domain protein molecule comprising of three distinct domains. Domain I is made of seven alpha-helices, domain II comprises three antiparallel beta sheets, which are folded into loops and domain III is made of a beta sandwich of two antiparallel beta strands. Molecular studies on the structure and functional properties of different &lt;FONT...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200009

Effect of the production or use of mixtures of bakers’ or brewers’ yeast extracts on their ability to promote growth of lactobacilli and pediococci
Provedor de dados: Electronic Journal of Biotechnology
Autores: Champagne,Claude P; Gaudreau,Hélène; Conway,John.
Three brewers’ and three bakers’ yeast extracts (YE) were obtained from five commercial suppliers. They were added to microbiological media and their growth-promoting properties were examined using four lactic cultures (Lactobacillus casei EQ28 and EQ85, Lactobacillus acidophilus EQ57, Pediococcus acidilactici MA18/5-M). Bakers’ YE have a higher total nitrogen content than brewers’ YE, but there was not always a correlation between the nitrogen content and growth. A systematic preference for bakers’ YE over brewers’ YE was only encountered with Lb. casei EQ85, but the other lactic cultures had variable reactions to the source of YE. With Lb. casei EQ85 and Pc. acidilactici 17/5M, mixing of the two sources of YE gave progressively higher growth as a...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300004

Electrogeneration of hydrogen peroxide applied to the peroxide-mediated oxidation of (R)-limonene in organic media
Provedor de dados: Electronic Journal of Biotechnology
Autores: La Rotta Hernández,Camilo Enrique; Werberich,Diogo Simon; Mattos,Marcio Contrucci Saraiva de; D'Elia,Eliane.
Horse radish peroxidase (HRP) from Armoracia rusticana catalyses the oxidation of (R)-limonene into the oxidized derivatives carveol and carvone. This study compares the direct addition (DA) of hydrogen peroxide with its continuous electrogeneration (EG) during the enzymatic oxidation of (R)-limonene. Reaction mixtures containing HRP, (R)-limonene as substrate, and hydrogen peroxide, added directly or electrogenerated, in 100 mM sodium-potassium phosphate buffer pH 7.0, at 25ºC were studied. Two electrochemical systems for the hydrogen peroxide electrogeneration were evaluated, both containing as auxiliary electrode (AE) a platinum wire and saturated calomel electrode (SCE) as reference. Reticulated vitreous carbon foam (RVCF) and an electrolytic copper...
Tipo: Journal article
Palavras-chave: Armoracia rusticana; Bioelectrochemistry; Carveol; Carvone; Horse-radish peroxidase; Hydrogen peroxide electrogeneration; (R)-limonene.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400006

A molecular marker approach using intron flanking EST-PCR to map candidate genes in peach (Prunus persica)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Diez-de-Medina,Sergio; Silva,Herman.
In Peach (Prunus persica) several physiological changes, such as woolliness, triggered by chilling injury are involved in major production losses due to cold storage of the fruits during shipping. Additionally, the low level of polymorphisms among peach varieties is an important limitation in the search for new molecular markers that could be associated with economically important traits. Therefore, a functional approach was employed to associate candidate genes with an informative marker in peach. The data was obtained from the results of an in silico analysis of four different cold peach treatments. Thirty two candidate genes were selected that were aligned against Arabidopsis thaliana genomic sequences to design intron-flanking EST-PCR markers. These...
Tipo: Journal article
Palavras-chave: Bin mapping; Molecular markers; Prunus; Rosaceae.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500007

Identification of microsatellites linked to Lr47
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vanzetti,Leonardo Sebastián; Brevis,Juan Carlos; Dubcovsky,Jorge; Helguera,Marcelo.
Leaf rust resistance gene Lr47 is located within a interstitial segment of Triticum speltoides Taush. 7S chromosome translocated to the short arm of chromosome 7A of bread wheat. This gene is resistant against currently predominant races of leaf rust from Argentina. The objectives of this study were to identify microsatellites linked to this source of resistance as a potential tool to introgress this source of resistance. Isogenic lines with and without Lr47 developed from 10 cultivars/breeding lines as well as 10 microsatellites previously mapped in 7AS chromosome were used in this study. Microsatellite gwm 60 was the only marker that co-segregated completely linked to Lr47. These data indicate that gwm 60 could be a valuable marker to introgress Lr47 in...
Tipo: Journal article
Palavras-chave: Gwm 60; Leaf rust; Marker assisted selection; Puccinia triticina Ericks.; Triticum aestivum.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300018

Teaching of Biotechnology in the Biochemistry Course
Provedor de dados: Electronic Journal of Biotechnology
Autores: de Oliveira Marques Serralheiro,Maria Luisa Mourato; Ponces Freire,Ana Maria.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300004

Simultaneous effects of pH and substrate concentration on hydrogen production by acidogenic fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cubillos,Genoveva; Arrué,Ramon; Jeison,David; Chamy,Rolando; Tapia,Estela; Rodríguez,Jorge; Ruiz-Filippi,Gonzalo.
The present research examined the effects of initial substrate concentration and pH on the yield and productivity of hydrogen production by acidogenic fermentation. Assays were carried out at three different initial pH levels (5.5, 6.5 and 7.5) and three initial substrate concentrations (3, 5 and 10 g COD/L). Glucose was used as carbon source and the experiments were conducted at 37°C in batch tests, after a thermal pretreatment to eliminate methanogenic microorganisms. Conversions of glucose into hydrogen were between 16.75 and 27.25% of theoretical maximum, and high values of hydrogen productivity were obtained. An optimum value for the yield of glucose between initial pH of 6.3 and 3.7 g COD/L and productivity of the 5.95 H2/gVSS h and initial pH of 6.7...
Tipo: Journal article
Palavras-chave: Acidogenic; Gompertz modified; Heat treatment; Hydrogen; Surface response.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100011

Biosorption of heavy metals from waste water using Pseudomonas sp.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hussein,Hany; Ibrahim,Soha Farag; Kandeel,Kamal; Moawad,Hassan.
Biosorption experiments for Cr(VI), Cu(II), Cd(II) and Ni(II) were investigated in this study using nonliving biomass of different Pseudomonas species. The applicability of the Langmuir and Freundlich models for the different biosorbent was tested. The coefficient of determination (R²) of both models were mostly greater than 0.9. In case of Ni(II) and Cu(II), their coefficients were found to be close to one. This indicates that both models adequately describe the experimental data of the biosorption of these metals. The maximum adsorption capacity was found to be the highest for Ni followed by Cd(II), Cu(II) and Cr(VI). Whereas the Freundlich constant k in case of Cd(II) was found to be greater than the other metals. Maximum Cr(VI) removal reached around...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000100006

Heterologous expression of staphylococcal enterotoxin B (seb) gene for antibody production
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vrat Kamboj,Dev; Nema,Vijay; Kumar Pandey,Arun; Kumar Goel,Ajay; Singh,Lokendra.
Staphylococcal food poisoning (SFP) is caused by the members of superantigen family called staphylococcal enterotoxins (SEs). About 20 different types of SEs are produced by Staphylococcus aureus out of which type A (SEA), B (SEB), C (SEC) and D (SED) are commonly implicated in SFP. Among these, SEB is the most potent toxin and has also gained the status of biological warfare (BW) agent. Therefore, detection of SEB is of utmost importance. Any immunological detection system for SEB requires specific and sensitive antibodies which inturn depends on the purity of the SEB. In the present investigation, seb gene of S. aureus was cloned and expressed in E. coli along with biotin as fusion partner to facilitate the purification process. The yield of purified...
Tipo: Journal article
Palavras-chave: Affinity purification; Biotin fusion; ELISA; Gene cloning; SEB; Western blot.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500010

Induction of in vitro roots cultures of Thypha latifolia and Scirpus americanus and study of their capacity to remove heavy metals
Provedor de dados: Electronic Journal of Biotechnology
Autores: Santos-Díaz,María del Socorro; Barrón-Cruz,María del Carmen; Alfaro-De la Torre,María Catalina.
We have established the conditions to obtain in vitro root cultures of Thypha latifolia and Scirpus americanus and have investigated their capacity to remove Pb(II), Mn(II) and Cr(III) from the culture medium. The best conditions for the in vitro culture growth were: an inoculum of 0.2 g of T. latifolia roots and 0.05 g of S. americanus roots (fresh weight), Murashige-Skoog medium and 2 mg L-1of indolacetic acid. The T. latifolia and S. americanus root cultures were cultivated onto media containing Cr (15 µg L-1), Pb (60 µg L-1) or Mn (1.8 mg L-1). Both species were able to remove Pb and Cr near to 100% and 71-100% of Mn from the medium solution during the 6-8 days of experimentation. According to metal concentrations removed from the medium containing the...
Tipo: Journal article
Palavras-chave: Heavy metals; In vitro root cultures; Phytoremediation; Scirpus americanus; Thypha latifolia.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300009

A simple method for isolation of genomic DNA from fresh and dry leaves of Terminalia arjuna (Roxb.) Wight and Arnot
Provedor de dados: Electronic Journal of Biotechnology
Autores: Deshmukh,Vishal P; Thakare,Prashant V; Chaudhari,Uddhav S; Gawande,Prashant A.
Current protocols for isolation of genomic DNA from Terminalia arjuna have their own limitations due to the presence of high content of gummy polysaccharides and polyphenols. DNA isolated by these protocols is contaminated with a yellowish, sticky and viscous matrix. In our modified DNA isolation method polysaccharides and polyphenols are removed prior to the precipitation of the DNA. Then the genomic DNA was precipitated using isopropanol. This protocol yielded a high molecular weight DNA isolated from fresh as well as dry leaves of T. arjuna, which was free from contamination and colour. Isolated DNA can be used for restriction digestion and PCR amplification. The main objective of the present protocol is to provide a simple method of isolation of DNA,...
Tipo: Journal article
Palavras-chave: Ayurveda; DNA extraction; Medicinal plant; Terminalia species.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300014

Isolation of total RNA from tissues rich in polyphenols and polysaccharides of mangrove plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rubio-Piña,Jorge A; Zapata-Pérez,Omar.
RNA extraction from mangrove tissues can be difficult due to the presence of polyphenolic and polysaccharide compounds upon cell disruption. Besides, a successful RNA isolation from mangrove tissues sometimes can be strain and species specific. Two different methods were used to extract RNA from tissues (stems, leaves and roots) of black mangrove (Avicennia germinans) and white mangrove (Laguncularia racemosa), collected from the mangrove area at Progreso, Yucatan, Mexico. An optimized and modified total RNA isolation method was developed for these recalcitrant species. The protocol is based on the CTAB method including &amp;#946;-mercaptoethanol and PVPP with sequential Phenol/Chloroform/isoamyl alcohol extractions to remove protein, and polyphenols,...
Tipo: Journal article
Palavras-chave: Mangrove; Plant tissues; Polysaccharides; RNA isolation.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500011

New strains obtained after UV treatment and protoplast fusion of native Trichoderma harzianum: their biocontrol activity on Pyrenochaeta lycopersici
Provedor de dados: Electronic Journal of Biotechnology
Autores: Besoain,Ximena A; Pérez,Luz María; Araya,Antonio; Lefever,Llacolén; Sanguinetti,; Montealegre,Jaime R.
The obtainment of 30 new strains from native Trichoderma harzianum after UV light irradiation (UV-A and UV-C), and of 82 strains resulted from protoplast fusion were accomplished. The new strains, initially selected for their growing rate under low temperature and high pH conditions, as well as for their innocuousness on tomato plants, were tested for in vitro inhibition of Pyrenochaeta lycopersici in dual cultures and due to secretion of volatile and diffusible metabolites. All the UV-A and UV-C selected candidate mutants were innocuous to tomato plants, but none of them showed improvement in their biocontrol activity on P. lycopersici. Th12A20.1 increased 1.3 and 1.9 fold the total fresh weight of Fortaleza tomato plants when compared to its parental...
Tipo: Journal article
Palavras-chave: Corky root; Mutagenesis; Tomato diseases; Trichoderma; Volatile and diffusible metabolites.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400013

PLANT BIOTECHNOLOGY IN THE 21ST CENTURY: THE CHALLENGES AHEAD
Provedor de dados: Electronic Journal of Biotechnology
Autores: Altman,Arie.
In a world where population growth is outstripping food supply agricultural -and especially plant-biotechnology, needs to be swiftly implemented in all walks of life. Achievements today in plant biotechnology have already surpassed all previous expectations, and the future is even more promising. The full realisation of the agricultural biotechnology revolution depends on both continued successful and innovative research and development activities and on a favourable regulatory climate and public acceptance. Biotechnology should be fully integrated with classical physiology and breeding: (1) as an aid to classical breeding, (2) for generation of engineered organisms, (3) for integration of microorganisms into agricultural production systems. Biotechnology...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000200001

Genomics and proteomics offers new hopes towards a personalized approach to lung cancer prevention and treatment
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gil,Lionel; Adonis,Marta.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000300002

Culturable fungi associated with urban stone surfaces in Mexico City
Provedor de dados: Electronic Journal of Biotechnology
Autores: Páramo-Aguilera,Leandro; Ortega-Morales,Benjamín Otto; Narváez-Zapata,José Alberto.
Background: Urban surface stones in Mexico City are exposed to a temperate climate and a range of atmospheric conditions ranging from mildly impacted to heavily polluted areas. In this study, we focused on the characterization of the cultivable fungal component of selected biological patinas in the surrounding area of Chapultepec castle, a historic monument in Mexico City. Thirty four representative fungal isolates selected based on distinctive differential macroscopic characteristics out of a total of 300 fungi, were characterized using morphological and molecular approaches. Results: This identification strategy based on the combination of phenotypic- and molecular-based methodologies allowed us to discriminate the fungal community in some cases down to...
Tipo: Journal article
Palavras-chave: Aeroterrestrial habitat; Fungi; Stone surfaces; Urban buildings.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000400004

Effect of inactivation and reactivation conditions on activity recovery of enzyme catalysts
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wilson,Lorena; Illanes,Andrés; Romero,Oscar.
Enzymes are labile catalysts with reduced half-life time that can be however improved by immobilization and, furthermore, already inactivated catalyst can be recovered totally or partially, therefore allowing the large scale application of enzymes as process catalysts. In recent years a few studies about reactivation of enzyme catalysts have been published as a strategy to prolong the catalyst lifetime. Reported results are very good, making this strategy an interesting tool to be applied to industrial process. These studies have been focused in the evaluation of different variables that may have a positive impact both in the rate and level of activity recovery, being then critical variables for conducting the reactivation process at productive scale. The...
Tipo: Journal article
Palavras-chave: CLEAs; Enzyme immobilization; Enzyme reactivation; Glyoxyl agarose; Inactivation; Organic cosolvents; Unfolding - refolding.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300015

Identification of a minimal microsatellite marker panel for the fingerprinting of peach and nectarine cultivars
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rojas,Gabriela; Méndez,Marco A; Muñoz,Carlos; Lemus,Gamalier; Hinrichsen,Patricio.
The genetic characterization of 117 peach and nectarine cultivars (Prunus persica (L.) Batsch) using microsatellite (SSR) markers is presented. Analyzed genotypes include the complete list of cultivars under intellectual property (IP) protection in Chile. One hundred and two out of the 117 cultivars under study could be identified using only 7 SSRs. Other 5 cultivars were differentiated using 3 additional markers, but 5 pairs of genotypes were not differentiable. The average expected heterozygosity for the set of markers was 0.55, ranging from 0.28 in BPPCT-008 to 0.81 in CPPCT-022, with an F value of 0.37. A Neighbor-Joining dendrogram showed that, with few exceptions, peaches and nectarines clustered separately. These results are the basis for the...
Tipo: Journal article
Palavras-chave: Cultivar identification; Fingerprinting; Prunus persica; Simple sequence repeats; SSR.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000500004

Salinity effects on protein content, lipid peroxidation, pigments, and proline in Paulownia imperialis (Siebold &amp;amp; Zuccarini) and Paulownia fortunei (Seemann &amp;amp; Hemsley) grown in vitro
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ayala-Astorga,Gloria Irma; Alcaraz-Meléndez,Lilia.
We evaluated the effects of saline stress on soluble proteins, lipid peroxidation (TBAR), chlorophyll a, chlorophyll b, &amp;#946;-carotene, violaxanthin, and proline in Paulownia imperialis and Paulownia fortunei plants grown in vitro. When the propagated plants reached a determined size, they were transferred aseptically to WPM culture medium containing different sodium chloride concentrations (0, 20, 40, 60, 80, and 160 mM) and were sampled at 15 and 30 days. Proline content was determined at 30 days after transfer only. Protein concentration significantly decreased with the highest salt levels in P. imperialis compared to controls in which no sodium chloride was added. In both P. imperialis and P. fortunei, lipid peroxidation significantly increased at...
Tipo: Journal article
Palavras-chave: Paulownia fortunei; Paulownia imperialis; Pigments; Proline; Proteins; Salinity; TBARS; Tissue culture.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500013

Modification of the activity of an alpha-amylase from Bacillus licheniformis by several surfactants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bravo Rodríguez,Vicente; Jurado Alameda,Encarnación; Martínez Gallegos,Juan Francisco; Reyes Requena,Antonia; García López,Ana Isabel; Sampaio Cabral,Joaquim Manuel; Fernandes,Pedro; Pina da Fonseca,Luis Joaquim.
The influence of different commercial surfactants on the enzymatic activity of a commercial alpha-amylase from Bacillus licheniformis (Termamyl 300 L) has been studied. As non-ionic surfactants, alkyl polyglycosides (Glucopon® 215, Glucopon® 600 and Glucopon® 650) were studied, as were fatty alcohol ethoxylates (Findet 1214N/23 and Findet 10/15), and nonyl phenol ethoxylate (Findet 9Q/21.5NF). Also, an anionic surfactant, linear alkyl benzene sulfonate (LAS) was assayed. In general, none of the non-ionic surfactants studied, except Findet 10/15, vary substantially the enzymatic activity. Findet 10/15 has the strongest hydrophobic character and reduces the enzymatic activity more significantly the greater its concentration. Regarding LAS, this surfactant...
Tipo: Journal article
Palavras-chave: Alpha-amylase; Alkyl polyglycosides; Enzymatic activity; Fatty alcohol ethoxylates; Linear alkyl benzene sulfonate; Nonyl phenol ethoxylate.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500012

Controlling proteolytic degradation of the methionine enriched MB-1Trp protein
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sasseville,Maxime; St-Louis,Catherine; Khoudi,Habib; Beauregard,Marc.
Protein design is currently used for the creation of new proteins with desirable traits, which include a superior nutritional value. One of the challenges of protein design in this area is to achieve the production of stable native-like proteins that resist the proteolytic pressure of the organism used for its production (the bioreactor). We report here the identification of a specific peptide bond sensitive to E. coli proteolysis in the designer protein MB-1Trp. In an attempt to reduce proteolysis, we have created a MB-1TrpHis gene library in which the two amino acids surrounding the peptide bond, N44 and L45, were randomized using degenerated oligonucleotides. The initial characterization of MB-1TrpHis N44E/L45V and MB-1TrpHis N44E/L45M, 2 variants of...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300004

Membrane damage of bacteria by silanols treatment
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kim,Yun-mi; Farrah,Samuel; Baney,Ronald H.
Antimicrobial action of silanols, a new class of antimicrobials, was investigated by transmission electron microscopy and fluorescent dye studies. Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa and Gram-positive bacteria, Staphylococcus aureus and Enterococcus faecalis were treated by silanols at concentration of less than 0.2 wt% for one hour. Membrane damage of the bacteria by the silanol treatment was clearly observed by transmission electron microscopy. Separation of the cytoplasmic membrane from the outer membrane for E. coli and disorganized cytoplasmic membrane of the Gram-positive bacteria were observed when compared to the control. Fluorescent dyes, green-fluorescent nucleic acid stain (Syto 9) and the red-fluorescent nucleic...
Tipo: Journal article
Palavras-chave: Antimicrobials; Hydrophobicity; Organosilicon compounds.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200009

Enhancement of biodegradation potential of catechol 1,2-dioxygenase through its immobilization in calcium alginate gel
Provedor de dados: Electronic Journal of Biotechnology
Autores: Guzik,Urszula; Hupert-Kocurek,Katarzyna; Marchlewicz,Ariel; Wojcieszynska,Danuta.
Background In biodegradation processes free enzymes often undergo deactivation. Thus, it is very important to obtain highly stable enzymes by different methods. Immobilization allows for successful stabilization of many multimeric enzymes by increasing the rigidity of the enzyme structure. This study aimed to evaluate some environmental factors that affect catechol 1,2-dioxygenase from Stenotrophomonas maltophilia KB2 immobilized in alginate hydrogel. The goal of the present work was to improve the functional stability of the enzyme by increasing its structural rigidity. Results Immobilization yield and expressed activity were 100% and 56%, respectively. Under the same storage conditions, the activity of the immobilized enzyme was still observed on the...
Tipo: Journal article
Palavras-chave: Arenes; Entrapment; Intradiol dioxygenase; Stenotrophomonas.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000200005

Xylanase and &amp;#946;-xylosidase from Penicillium janczewskii: Purification, characterization and hydrolysis of substrates
Provedor de dados: Electronic Journal of Biotechnology
Autores: Fanchini Terrasan,César Rafael; Guisan,José Manuel; Cano Carmona,Eleonora.
Background: Xylanases and &amp;#946;-D-xylosidases are the most important enzymes responsible for the degradation of xylan, the second main constituent of plant cell walls. Results: In this study, the main extracellular xylanase (XYL I) and p-xylosidase (BXYL I) from the fungus Penicillium janczewskii were purified, characterized and applied for the hydrolysis of different substrates. Their molecular weights under denaturing and non-denaturing conditions were, respectively, 30.4 and 23.6 kDa for XYL I, and 100 and 200 kDa for BXYL I, indicating that the latter is homodimeric. XYL I is highly glycosylated (78%) with optimal activity in pH 6.0 at 65°C, while BXYL I presented lower sugar content (10.5%) and optimal activity in pH 5.0 at 75°C. The half-lives...
Tipo: Journal article
Palavras-chave: Xylanolytic enzymes; Enzyme characterization; Enzyme purification; Xylan hydrolysis; Xylooligosaccharides hydrolysis.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500006

Mitotic aberrations in coffee (Coffea arabica cv. 'Catimor') leaf explants and their derived embryogenic calli
Provedor de dados: Electronic Journal of Biotechnology
Autores: Menéndez-Yuffá,Andrea; Fernandez Da Silva,Rafael; Rios,Liliana; Xena de Enrech,Nereida.
Dividing cells of leaves used as sources of explants from coffee plants (Coffea arabica cv. 'Catimor') and those of their derived calli were analyzed for mitotic aberrations. The studied tissues were prepared by squashing and stained with carbolfuchsin. A total of 1551 leaf and 4568 callus cells were surveyed. The majority (79 %) of leaf and calli (75 %) cells showed normal mitosis, however, cells with mitotic abnormalities were also found in both tissues. These included: polyploids, aneuploids, sticky chromosomes, double prophases and lagging chromosomes. Additionally, interphase cells with micronuclei or binucleated were also observed. The frequencies of these abnormalities were statistically different in calli and leaves. Calli showed a few other...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000200008

Preservation of endangered Tunisian grapevine cultivars using embryogenic cultures
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bouamama,Badra; Jardak,Rahma; Salem,Asma Ben; Ghorbel,Abdelwahed; Mliki,Ahmed.
The preservation of embryogenic lines derived from several endangered local grapevine cultivars was studied. Embryogenic calluses were obtained from immature anthers of eight cultivars, sampled on both fruity-cuttings and field grown vines. Anthers at the 'separated flower' stage, derived from fruity-cuttings, resulted in an increased induction of somatic embryogenesis, compared to those derived from the field. Pro-embryogenic calluses were induced on Chée and Pool (1987) basal medium, supplemented with 9 µM of 2,4-dichlorophenoxyacetic acid (2,4-D) and 11.35 µM of thidiazuron (TDZ) under dark conditions. Different anther zones (filament, abaxial, adaxial, lateral zones and entire anthers) were involved in somatic embryogenesis induction. The percentages...
Tipo: Journal article
Palavras-chave: Forced anthers; Long-term maintenance; Somatic embryos; Vitis vinifera.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200006

Thermostable lipase from a newly isolated Staphylococcus xylosus strain; process optimization and characterization using RSM and ANN
Provedor de dados: Electronic Journal of Biotechnology
Autores: Khoramnia,Anahita; Lai,Oi Ming; Ebrahimpour,Afshin; Tanduba,Carynn Josue; Voon,Tan Siow; Mukhlis,Suriati.
Normal feed forward back-propagation artificial neural network (ANN) and cubic backward elimination response surface methodology (RSM) were used to build a predictive model of the combined effects and optimization of culture parameters for the lipase production of a newly isolated Staphylococcus xylosus. The results demonstrated a high predictive accuracy of artificial neural network compared to response surface methodology. The optimum operating condition obtained from the ANN model was found to be at 30ºC incubation temperature, pH 7.5, 60 hrs incubation period, 1.8% inoculum size and 60 rpm agitation. The lipase production increased 3.5 fold for optimal medium. The produced enzyme was characterized biochemically and this is the first report about a...
Tipo: Journal article
Palavras-chave: Artificial neural network; Characterization; Lipase; Optimization; Response surface methodology; Staphylococcus xylosus.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500015

Isolation of a UDP-glucose: Flavonoid 5-O-glucosyltransferase gene and expression analysis of anthocyanin biosynthetic genes in herbaceous peony (Paeonia lactiflora Pall.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhao,Da Qiu; Han,Chen Xia; Ge,Jin Tao; Tao,Jun.
Herbaceous peony (Paeonia lactiflora Pall.) is an excellent material for studying the formation of flower colour because of its abundant colour. The full-length cDNA of a UDP-glucose: Flavonoid 5-O-glucosyltransferase gene (UF5GT) containing 1629 bp nucleotides was obtained from P. lactiflora. The expression patterns of nine related anthocyanin biosynthetic genes (PlPSY, PlCHS, PlCHI, PlF3H, PlF3'H, PlDFR, PlANS, PlUF3GT and PlUF5GT) in diurnal variation petals showed that their expression peaks were basically at 15:00 and the expression patterns were consistent with the trend of sampling conditions except individual gene. And the highest expression levels were in PlCHS, PlDFR and PlUF3GT, which could be the candidates to regulate P. lactiflora flower...
Tipo: Journal article
Palavras-chave: Anthocyanin; Expression; Glucosyltransferase; Herbaceous peony.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600009

Identification of leaf rust resistance genes in selected Argentinean bread wheat cultivars by gene postulation and molecular markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vanzetti,Leonardo Sebastián; Campos,Pablo; Demichelis,Melina; Lombardo,Lucio Andres; Aurelia,Paola Romina; Vaschetto,Luis María; Bainotti,Carlos Tomás; Helguera,Marcelo.
Leaf rust, caused by Puccinia triticina Eriks. is a common and widespread disease of bread wheat (Triticum aestivum L.), in Argentina. Host resistance is the most economical, effective and ecologically sustainable method of controlling the disease. Gene postulation helps to determine leaf rust resistance genes (Lr genes) that may be present in a large group of wheat germplasm. Additionally presence of Lr genes can be determined using associated molecular markers. The objective of this study was to identify Lr genes that condition leaf rust resistance in 66 wheat cultivars from Argentina. Twenty four differential lines with individual known leaf rust resistance genes were tested with 17 different pathotypes of leaf rust collected from Argentina. Leaf rust...
Tipo: Journal article
Palavras-chave: Genetic control of pathogens; Molecular markers; Plant breeding.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300009

Influence of various fermentation variables on exo-glucanase production in Cellulomonas flavigena
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rajoka,Muhammad Ibrahim.
The influence of carbon and nitrogen sources on the production of exo-glucanase was investigated. The enzyme production was variable according to the carbon or nitrogen source used. Levels of beta-cellobiohydrolase (CBH) were minimal in the presence of even low concentrations of glucose. Enzyme production was stimulated by other carbohydrates and thus is subject to carbon source control by easily metabolizable sugars. In Dubos medium, on cellobiose, the cellobiohydrolase titres were 2-to 110-fold higher with cells growing on monomeric sugars and 2.7 times higher than cells growing on other disaccharides. alpha-Cellulose was the most effective inducer of beta-cellobiohydrlase and filter paperase (FPase) activities, followed by kallar grass straw....
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000300007

Comparing the expression of human DNA topoisomerase I in KM71H and X33 strains of Pichia pastoris
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ping,Ruo; Sin Teoh,Leong; Kwai Chan,Mooi; Miswan,Noorizan; Yin Khoo,Boon.
Background: Human is an essential cellular enzyme that is found in all human cells. As this enzyme is upregulated in cancer cells exceedingly, it is used as a target for cancer chemotherapeutic drug development. As such, producing the in-house enzyme for the purpose to speed up the search for more cost-effective and target specific hTopoI inhibitors is warranted. This study aims to compare the optimised conditions for the expression of hTopoI in KM71H (MutS) and X33 (Mut+) strains of Pichia pastoris. P. pastoris transfected with an hTopoI recombinant vector was used for the optimization of a higher level of hTopoI expression. Results: In the process, fed-batch cultivation parameters that influence the expression of hTopoI, such as culture temperature,...
Tipo: Journal article
Palavras-chave: Cell density; Pichia pastoris; Total protein concentration; Recombinant protein expression.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300001

Knowledge about and acceptance of genetically modified organisms among pre-service teachers: a comparative study of Turkey and Slovenia
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sorgo,Andrej; Ambrozic-Dolinsek,Jana; Usak,Muhammet; Özel,Murat.
Genetically modified organisms cannot be regarded as merely a topic for academic debate, since these have serious implications as a research field and for production based on genetic engineering. Public debates rarely base their arguments on elements rooted in scientific arguments and knowledge but are heavily loaded with emotions, opinions and informal reasoning. This study aimed to investigate the knowledge and acceptance of genetically modified organisms among prospective teachers in Slovenia and Turkey. Knowledge of genetic modification was measured with a two-tier instrument. The level of acceptance of genetic modification was measured with a 17-item instrument. Findings revealed that knowledge of genetics and biotechnology barely influenced the...
Tipo: Journal article
Palavras-chave: Biotechnology; Genetic engineering; Genetic modifications; Teaching.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400005

Application of rice (Oryza sativa L.) suspension culture in studying senescence in vitro (II).: Changes in DNA integrity
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ramin,Hosseini; Mulligan,Bernard J.
Changes in the DNA content and organisation of senescing rice cell cultures (Taipei 309) were studied, using PCR and Southern blot analyses. A mitochondrial gene (coxII), a plastid gene (psaA) and a nuclear DNA maker (RG64) were analysed. The amplification of mitochondrial (mt), plastid and nuclear DNA produced the expected fragments, indicating that there were still some intact organelles and nuclei in the senescing rice cells. However, in plastid and nuclear DNA, changes in the number and size of the PCR products were observed. Southern blot analysis revealed that mt and nuclear DNA contents declined, but plastid DNA content remained relatively the same throughout the senescence.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100012

Application of rice (Oryza sativa L.) suspension culture in studying senescence in vitro (I).: Single strand preferring nuclease activity
Provedor de dados: Electronic Journal of Biotechnology
Autores: Hosseini,Ramin; Mulligan,Bernard J.
Single Strand-Preferring Nucleases (SSPNs) have been implicated in the triggering and progress of cell death pathways, including senescence in higher plants, though the biological roles of such enzymes are still obscure. In the present study, heterotrophic cell suspension cultures of Oryza sativa L. (rice) cv Taipei 309 were used to investigate changes in Single Strand-Preferring Nuclease activity associated with cell death in vitro. An acid nuclease activity (pH 5.5) was found which was strongly stimulated in the presence of 10 mM Zn2+ and inhibited by 10 mM EDTA and EGTA. An increase in SSPN activity was concomitant with a loss of cell viability, total protein and the onset of stationary phase of growth in the cell cultures. Using DNA-SDS-PAGE two major...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100011

A novel pH-stable, endoglucanase (JqCel5A) isolated from a salt-lake microorganism, Jonesia quinghaiensis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lin,Ling; Liu,Xiaozhou; Zhou,Yating; Guan,Linyan; Jiajia,He; Huang,Weiqian.
Background: Endoglucanase, one of three type cellulases, can randomly cleave internal p-1,4-linkages in cellulose polymers. Thus, it could be applied in agricultural and industrial processes. Results: A novel endoglucanase gene (JqCel5A) was cloned from Jonesia quinghaiensis and functionally expressed in Escherichia coli Rosetta (DE3). It contained 1722 bp and encoded a 573-residue polypeptide consisting of a catalytic domain of glycoside hydrolase family 5 (GH5) and a type 2 carbohydrate-binding module (CBM2), together with a predicted molecular mass of 61.79 kD. The purified JqCel5A displayed maximum activity at 55°C and pH 7.0, with 21.7 U/mg, 26.19 U/mg and 4.81 U/mg towards the substrate carboxymethyl cellulose, barley glucan and filter paper,...
Tipo: Journal article
Palavras-chave: Protein modeling Site-directed mutagenesis Cellulases Recombinant endoglucanase gene Catalytic domain ofglycoside hydrolase Carbohydrate-binding module High pH stability Tolerance to deleterious chemicals; Tolerance to heavy metals Tolerance to detergents.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600009

Rapamycin pre-treatment abrogates Tumour Necrosis Factor-&amp;#945; down-regulatory effects on LXR-Î± and PXR mRNA expression via inhibition of c-Jun N-terminal kinase 1 activation in HepG2 cells
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ng,Di-Lin; Tie,Shin-Wei; Ong,Pei-Chin; Lim,Wyi-Sian; Tengku-Muhammad,Tengku-Sifzizul; Choo,Quok-Cheong; Chew,Choy-Hoong.
The Liver X Receptor (LXR) and Pregnane X Receptor (PXR) are members of the nuclear receptor superfamily. Previously, they have been classified as important regulators of lipid homeostasis. However, recent studies have shown that they may be implicated in anti-inflammatory responses as well. This study shows that Tumour Necrosis Factor-Î± (TNF-Î±) treatment reduces both LXR-Î± and PXR mRNA expression. However, pre-treatment with rapamycin, an mTOR inhibitor, followed by TNF-Î± stimulation, significantly induces LXR-Î± and PXR mRNA expression to ~17- and ~2-fold, respectively. This suggests that mTORC1, a multi-molecular complex of which mTOR is a member, may act as a negative regulator that inhibits the induction of LXR-Î± and PXR as anti-inflammatory...
Tipo: Journal article
Palavras-chave: Akt; C-Jun; Homeostasis; Inflammation; MKK7; Transcription factor.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300008

Application of bacterial and yeast biosurfactants for enhanced removal and biodegradation of motor oil from contaminated sand
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chaprão,Marcos J; Ferreira,Isabela N.S; Correa,Priscilla F; Rufino,Raquel D; Luna,Juliana M; Silva,Elias J; Sarubbo,Leonie A.
Background This study investigated the potential application of two biosurfactants for enhanced removal capability and biodegradation of motor oil contaminated sand under laboratory conditions. The biosurfactants were produced by the yeast Candida sphaerica and by the bacterium Bacillus sp. cultivated in low-cost substrates. The ability of removing motor oil from soil by the two biosurfactants was identified and compared with that of the synthetic surfactants Tween 80 and Triton X-100. Results Both crude and isolated biosurfactants showed excellent effectiveness on motor oil removal from contaminated sand under kinetic conditions (70-90%), while the synthetic surfactants removed between 55 and 80% of the oil. A contact time of 5-10 min under agitation...
Tipo: Journal article
Palavras-chave: Bacillus sp; Bioremediation; Candida sphaerica; Petroleum; Sand-packed column.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600014

Biocatalytic oxidative kinetic resolution of (±)-4-(chlorophenyl)phenylmethanol by Nocardia corallina B-276
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ramírez,Mario A.; Pérez,Herminia I.; Manjarrez,Norberto; Solís,Aida; Luna,Héctor; Cassani,Julia.
Chiral diarylmethanols are versatile building blocks for the preparation of biologically active substances, but they are difficult to obtain in enantiopure form. We used Nocardia corallina B-276 for the oxidative kinetic resolution of (±)-4-(chlorophenyl)phenylmethanol, 1. Two experimental methods were used: 1) Suspension of cells in a phosphate buffer solution and 2) Cells in the culture media, in a 3-L bioreactor. After 36 hrs using the first method, the ketone/alcohol ratio was 56/44 and the unoxidized alcohol had an enantiomeric ratio of 93/7, predominating the R-alcohol.
Tipo: Journal article
Palavras-chave: 4-chlorobenzophenone; Biocatalysis; Microbial oxidation; Resolution.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000400002

Development of Biotechnology in South Africa
Provedor de dados: Electronic Journal of Biotechnology
Autores: Burton,Stephanie G.; Cowan,Don A.
Biotechnology in South Africa stands at a cross-roads. As a country with huge natural resources, equally huge social problems, and in a state of positive transition to full multi-cultural development, SA faces the complex task of effectively exploiting its science, technology and resource base for the benefit of its society. The potential of Biotechnology for social and economic development has only recently been a focal point. There are signs, at all levels from central administration to individual tertiary institutions, that the first decade of the 21st century may be the point where Biotechnology ‘comes of age’ in South Africa.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000100004

Non-destructive in vitro selection of microspore-derived embryos with the fertility restorer gene for CMS Ogu-INRA in winter oilseed rape (Brassica napus L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Havlí&amp;#269;ková,Lenka; Klíma,Miroslav; P&amp;#345;ibylová,Marie; Hilgert-Delgado,Alois Antonín; Ku&amp;#269;era,Vratislav; &amp;#268;urn,Vladislav.
Background Microspore embryogenesis and cytoplasmic male sterility system (CMS) are two approaches widely exploited in Brassica napus breeding for production of homozygous doubled haploid (DH) lines and F1 hybrids respectively. Cytoplasmic male sterility system (CMS) is one of the most important pollination systems for hybrid seed production and utilisation of doubled haploid system to quickly prepare fully homozygous fertility restorer lines for CMS Ogu-INRA is very beneficial. Generally, only a small part of microspore-derived embryos is used for plant regeneration, without any knowledge about their properties. Therefore, the possibility of early detection of desirable genotypes bearing a single dominant nuclear fertility restorer (Rfo) gene, can double...
Tipo: Journal article
Palavras-chave: Cytoplasmic male sterility; Microspore embryogenesis; Ogura CMS; Oilseed rape; Rfo gene.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100011

A rapid and cheap protocol for preparation of PCR templates in peanut
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Chuan Tang; Wang,Xiu Zhen; Tang,Yue Yi; Zhang,Jian Cheng; Yu,Shan Lin; Xu,Jian Zhi; Bao,Zhen Min.
This paper describes a simple, low cost and reliable DNA template preparation protocol for polymerase chain reaction (PCR) using immature leaves from peanut seeds or leaves from field-grown plants. The technique may find wide utility in studies involving PCR-based molecular markers, rapid screening for transformants and gene cloning.
Tipo: Journal article
Palavras-chave: DNA extraction; Groundnut; PCR; Peanut.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200009

Cytokinin preconditioning enhances multiple shoot regeneration in Pongamia pinnata (L.) Pierre - a potential, non-edible tree seed oil source for biodiesel
Provedor de dados: Electronic Journal of Biotechnology
Autores: Belide,Srinivas; Sajjalaguddam,Ramgopal Rao; Paladugu,Anitha.
An efficient, highly reproducible protocol for multiple shoot induction and plant regeneration of Pongamia pinnata has been successfully developed using cotyledonary node explants. This study also demonstrates that preconditioning of explant stimulates production of multiple shoots from cotyledonary nodes of P. pinnata. The highest direct shoot regeneration (90%) with an average of 18.4 ï¿½ 3.1 shoots/explant were obtained when cotyledonary node explants were excised from seedlings germinated on Murashige and Skoog (MS) media supplemented with benzyladenine (BA) 1 mg l-1, and subsequently cultured on MS media with 1 mgl-1 thidiazuron (TDZ). Scanning electron microscope observations of cotyledonary node (CN) explants excised from pre-conditioned and normal...
Tipo: Journal article
Palavras-chave: Benzyladenine; Cotyledonary node; Multiple shoot induction; Scanning electron microscopy; Thidiazuron.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600003

Utilization of coconut oil mill waste as a substrate for optimized lipase production, oil biodegradation and enzyme purification studies in Staphylococcus pasteuri
Provedor de dados: Electronic Journal of Biotechnology
Autores: P,Kanmani; K,Kumaresan; J,Aravind.
Background Oil and grease laden wastewaters pose hindrance to the treatment units and further threaten the receiving water bodies. Lipase-producing microbial strains are increasingly being exploited for the remediation of such effluents. Results When bacterial strains isolated from oil mill effluent were screened for their lipolytic activity, two isolates, COM-4A and COM-6B showed significant extracellular lipase activity. They were identified to be Staphylococcus pasteuri and Bacillus subtilis, respectively. S. pasteuri COM-4A was cultivated in nutrient media based on coconut oil mill waste (CMW), in which it showed good growth at concentrations up to 20 g/L. While growing in such media, it was capable of producing lipase and other important extracellular...
Tipo: Journal article
Palavras-chave: Bioremediation; Fat and oil contaminants; Ion exchange chromatography; Lipase characterization; Response surface methodology.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100005

Viability in protoplasts and cell suspensions of Coffea arabica cv. Catimor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Fernandez-Da Silva,Rafael; Menéndez-Yuffá,Andrea.
Two methods were evaluated in order to assess the viability of protoplasts and cell suspensions of Coffea arabica cv. Catimor used in a protocol of transformation by electroporation. One method consisted of staining with 1 % Evans blue and the other staining with 1% 3-[4,5-dimethyltiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT). When Evans blue was applied to viable cells and protoplasts they either did not stain or acquired a faint blue colour. However, it was difficult to distinguish the non-viable cells in the wide spectrum of clear blue tonalities. In contrast, with the MTT assay only the viable cells and protoplasts reduced this salt to the red coloured formazan; viable and non-viable cells were distinguished more clearly with MTT than with Evans...
Tipo: Journal article
Palavras-chave: Cell suspensions; Cell viability; Coffee; Evans blue; MTT; Protoplasts.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500016

Efficiency of RAPD and ISSR markers system in accessing genetic variation of rice bean (Vigna umbellata) landraces
Provedor de dados: Electronic Journal of Biotechnology
Autores: Muthusamy,Saraladevi; Kanagarajan,Selvaraju; Ponnusamy,Shanmugasundaram.
Vigna umbellata (Thunb.) Ohwi and Ohashi commonly known as rice bean or climbing mountain bean is under-exploited tropical legume. Genetic variation between 10 landraces of rice bean was evaluated using random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) markers. Among these markers, RAPD primers generated 987 amplification products of which 719 were polymorphic and ISSR markers produced 479 amplification products, out of which 296 were polymorphic. RAPD fingerprinting detected more polymorphic loci (70.30%) than the ISSR fingerprinting (61.79%). Mean PIC (polymorphism information content) for each of these marker systems (0.243 for RAPD and 0.203 for ISSR) suggested that both the marker systems were equally effective in...
Tipo: Journal article
Palavras-chave: Genetic diversity; ISSRs; Landraces; Rice bean; RAPDs; Vigna umbellata.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300004

Biosorption kinetics of a direct azo dye Sirius Blue K-CFN by Trametes versicolor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Erden,Emre; Kaymaz,Yasin; Pazarlioglu,Nurdan Kasikara.
In this study, lyophilized Trametes versicolor biomass is used as a sorbent for biosorption of a textile dye, Sirius Blue K-CFN, from an aqueous solution. The batch sorption was studied with respect to dye concentration, adsorbent dose and equilibrium time. The effect of pH and temperature on dye uptake was also investigated and kinetic parameters were determined. Optimal initial pH (3.0), equilibrium time (2 hrs), initial dye concentration ( 100 mg l-1) and biomass concentration (1.2 mg l-1) were determined at 26ï¿½C. The maximum biosorption capacity (q max) of Sirius Blue K-CFN dye on lyophilized T. versicolor biomass is 62.62 mg/g. The kinetic and isotherm studies indicated that the biosorption process obeys to a pseudo-second order model and Langmuir...
Tipo: Journal article
Palavras-chave: Biosorbent; Biosorption; Direct dye; Kinetics; Sirius Blue K-CFN; Trametes versicolor.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200003

Predicting regulatory elements in repetitive sequences using transcription factor binding sites
Provedor de dados: Electronic Journal of Biotechnology
Autores: Horng,Jorng-Tzong; Cho,Wen-Fu.
Repeat sequences are the most abundant ones in the extragenic region of genomes. Biologists have already found a large number of regulatory elements in this region. These elements may profoundly impact the chromatin structure formation in nucleus and also contain important clues in genetic evolution and phylogenic study. This study attempts to mine rules on how combinations of individual binding sites are distributed repeat sequences. The association rules mined would facilitate efforts to identify gene classes regulated by similar mechanisms and accurately predict regulatory elements. Herein, the combinations of transcription factor binding sites in the repeat sequences are obtained and, then, data mining techniques are applied to mine the association...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000300004

Assessment of microalgae and nitrifiers activity in a consortium in a continuous operation and the effect of oxygen depletion
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vargas,Gustavo; Donoso-Bravo,Andrés; Vergara,Christian; Ruiz-Filippi,Gonzalo.
Background: Industrial wastewaters with a high content of nitrogen are a relevant environmental problem. Currently, treatments to remove nitrogen are not efficient, so is necessary to develop alternative methods. The objective of this study is to investigate a consortium of microalgae - nitrifying, that due to the symbiosis between them could be an interesting alternative. Results: In this study, it was possible to obtain a consortium of nitrifying bacteria (NB) and microalgae (MA) capable of operating with low requirements of dissolved oxygen, using aerobic sludge from wastewater treatment plants. During the operation, this consortium presents removal percentages above 98% of ammonia, even at concentrations of DO of 0.5 mg O2 L-1. It is estimated that the...
Tipo: Journal article
Palavras-chave: Ammonium; Consortium nitrifying-microalgae; Oxygen; Respirometry.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500007

A strategy to identify genomic expression at single-cell level or a small number of cells
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Biaoru.
Recent advances in functional genomics allow us to estimate the expression of several thousands of genes in the mammalian genome. Techniques such as microarrays, expressed tag sequencing (EST), serial analysis of gene expression (SAGE), subtractive cloning and differential display (DD), and two-dimensional electrophoresis gel have been extensively used to screen and analyze parallel gene expression. Some pathological processes, for example, tumorigenesis and solid tumour growth, in which the former is derived from a single-cell and the latter has a mixed-cell problem, present new challenges to the limit of these functional genomic techniques. To fully understand the functions of cells in tumorigenesis or in heterogeneous solid tumour masses, it is...
Tipo: Journal article
Palavras-chave: Genome; Genomic expression; Genomic expression analysis at single cell; Single cell.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100011

Amplification of genome-integrated BeYDV replicons by transient expression of Rep in Arabidopsis thaliana
Provedor de dados: Electronic Journal of Biotechnology
Autores: Moon,Yong-Sun; Hefferon,Kathleen L.
Bean yellow dwarf geminivirus (BeYDV) has been used as a potential vector to improve foreign gene expression, specifically, to achieve higher yields of vaccine proteins in plants. Previously, we have shown that when the BeYDV replication initiator protein Rep was provided in trans, replication and gene expression of GUS were enhanced enormously from a BeYDV expression vector in a transient assay system. In this paper, transgenic lines of Arabidopsis (cv. Columbia) were generated harboring the BeYDV cis-acting elements required for replication. Constructs encoding BeYDV Rep or intronless Rep open reading frames (ORFs) were transiently introduced into transgenic plants via Agrobacterium-mediated infiltration in order to examine the relative levels of...
Tipo: Journal article
Palavras-chave: Agrobacterium-mediated expression; BeYDV-based vector; Gene amplification; GUS expression; Rep expression; Transgenic Arabidopsis.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400001

Antimicrobial and molecular interaction studies on derivatives of curcumin against Streptococcus pneumoniae which caused pneumonia
Provedor de dados: Electronic Journal of Biotechnology
Autores: Li,Liang-Mei; Li,Jun; Zhang,Xiu-Ying.
Background: The antimicrobial properties and molecular interaction analysis of curcumin and its derivatives against three different strains of Streptococcus pneumoniae (Penicillin-susceptible, Penicillin-intermediate and Penicillin-resistant) are studied. Results: These properties were analyzed based on the measurement of the inhibition zone, minimum inhibitory concentration (MIC), and rate of kill revealed that curcumin monoglucoside, curcumin diglucoside and curcumin possessed strong antimicrobial properties even on the Penicillin-resistant strains. Additionally, the molecular docking simulation analyses against Penicillin Binding Protein of S. pneumoniae also confirm that these compounds docked at the active site of the enzyme. Further, the molecular...
Tipo: Journal article
Palavras-chave: Antimicrobial; Curcumin; MIC; Molecular docking; Penicillin-resistant.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000100002

Identification of phase relative genes in tetrasporophytes and female gametophytes of Gracilaria/Gracilariopsis lemaneiformis (Gracilariales, Rhodophyta)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ren,Xueying; Zhang,Xuecheng; Sui,Zhenghong.
Genes differentially expressed between tetrasporophytes and female gametophytes of Gracilaria/Gracilariopsis lemaneiformis were isolated by suppression subtractive hybridization (SSH) and screened by dot-blot macro-arrays. Different expression profiles of selected clones based on the results of dot-blot macro-arrays were verified using virtual Northern blots. Totally, 14 phase relative cDNAs had been isolated and sequence identified. Among them, seven cDNAs were respectively homologous to crucial metabolic enzymes, Rab GTPase, RP42 homolog, and two hypothetical proteins, while the rest did not have significant hits in the databases examined. The results of virtual Northern blots revealed that 11 cDNAs were differentially expressed between the two samples,...
Tipo: Journal article
Palavras-chave: Female gametophyte; Gracilaria/Gracilariopsis lemaneiformis; Suppression subtractive hybridization; Tetrasporophyte; Virtual Northern blot.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200006

A legume genomics resource: The Chickpea Root Expressed Sequence Tag Database
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jayashree,B; Buhariwalla,Hutokshi K; Shinde,Sanjeev; Crouch,Jonathan H.
Chickpea, a lesser-studied grain legume, is being investigated due to its taxonomic proximity with the model legume genome Medicago truncatula and its ability to endure and grow in relatively low soil water contents making it a model legume crop for the study of agronomic response to drought stress. Public databases currently contain very few sequences from chickpea associated with expression in root tissues. However, root traits are likely to be one of the most important components of drought tolerance in chickpea. Thus, we have generated a set of over 2800 chickpea expressed sequence tags (ESTs) from a library constructed after subtractive suppressive hybridization (SSH) of root tissue from two closely related chickpea genotypes possessing different...
Tipo: Journal article
Palavras-chave: Cloning; Data mining; Drought avoidance; Drought tolerance; EST database; Root traits; Stress.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200002

Polymorphism of three milk protein genes in Mexican Jersey cattle
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zepeda-Batista,José Luis; Alarcón-Zúñiga,Baldomero; Ruíz-Flores,Agustín; Núñez-Domínguez,Rafael; Ramírez-Valverde,Rodolfo.
The objective was to estimate the allelic and genotypic frequencies, genetic diversity and polymorphic information content for the &amp;#946;-casein, &amp;#954;-casein and &amp;#946;-lactoglobulin genes. Blood and frozen semen samples were collected from 453 Jersey individuals registered by the Mexican Jersey Cattle Association. Twenty eight breed specific SNP primers for whole genes were used. The B allele of &amp;#954;-casein had higher frequency (0.69) than the A (0.26) and E (0.05). For &amp;#946;-lactoglobulin, the highest frequency was for B (0.72), followed by A and C alleles (0.26 and 0.02, respectively). The &amp;#946;-casein allele with the highest frequency was A² (0.71), followed by A¹ (0.19), A³ (0.05), B (0.04) and C (0.01). The average...
Tipo: Journal article
Palavras-chave: &amp;#946; -Casein &amp;#946; -Lactoglobulin Genetic diversity &amp;#954; -Casein.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100001

Enhanced production of dimethyl phthalate-degrading strain Bacillus sp. QD14 by optimizing fermentation medium
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mo,Jixian; Wang,Zhigang; Xu,Weihui; Li,Shanshan; Yu,Zhidan.
Background Integrated statistical experimental designs were applied to optimize the medium constituents for the production of a dimethyl phthalate (DMP)-degrading strain Bacillus sp. QD14 in shake-flask cultures. A Plackett-Burman design (PBD) was applied to screen for significant factors, followed by the Steepest Ascent Method (SAM) to find the nearest region of maximum response. A Box-Behnken design (BBD) of the Response Surface Methodology (RSM) was conducted to optimize the final levels of the medium components. Results After the regression equation and response surface contour plots were analyzed, the concentrations of glucose, corn meal and NaCl were found to significantly influence the biomass of DMP-degrading bacteria. A combination of 22.88 g/L of...
Tipo: Journal article
Palavras-chave: Bacillus; Box-Behnken design; Dimethyl phthalate; Medium optimization; Plackett-Burman design.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300016

Studies on statistical optimization of sulforaphane production from broccoli seed
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wu,Yuanfeng; Mao,Jianwei; Mei,Lehe; Liu,Shiwang.
Background: Natural sulforaphane (SF) has been of increasing interest for nutraceutical and pharmaceutical industries due to its anti-cancer effect. The main objective of the present work was to optimize the production of SF from broccoli seed using response surface methodology. Results: Three major factors (hydrolysis time, water volume and ethyl acetate volume) were screened out through Plackett-Burman (PB) factorial design. The methods of steepest ascent combined with central composite design (CCD) were employed for optimization of the SF production process. The optimal extraction conditions for SF production were a hydrolysis time of 13 min, a hydrolysis volume/weight ratio of 2.9:1 (v/g) and an extraction volume/weight ratio of 17.5:1 (v/g). The...
Tipo: Journal article
Palavras-chave: Broccoli seed; Central composite design; Plackett-Burman design; Production; Sulforaphane.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600001

Isolation of simple sequence repeats from groundnut
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tang Wang,Chuan; Dao Yang,Xin; Xu Chen,Dian; Lin Yu,Shan; Zhen Liu,Guang; Yi Tang,Yue; Zhi Xu,Jian.
SSRs have proved to be the most powerful tool for variety identification in groundnut of similar origin, and have much potential in genetic and breeding studies. To facilitate SSR discovery in groundnut, we proposed a highly simplified SSR isolation protocol based on multiple enzyme digestion/ligation, mixed biotin-labeled probes and streptavidin coated magnetic beads hybridization capture strategy. Of the 272 colonies randomly picked for sequencing, 119 were found to have unique SSR inserts
Tipo: Journal article
Palavras-chave: Groundnut; Isolation; Simple sequence repeat.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300015

Effect of isomalto-oligosaccharide and gentio-oligosaccharide on the growth and fatty acid profile of Lactobacillus plantarum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Soto,Carmen.
Background: Lactobacillus sp. are probiotic microorganisms, and some of them are able to produce conjugated linoleic acid (CLA) via the bio-hydrogenation of linoleic acid (LA). Both CLA and LA are polyunsaturated fatty acids commonly used in the prevention and control of cardiovascular disease, high cholesterol, and cancer, among other ailments. The carbon source is one variable that can affect the growth and characteristics of these bacteria. Molecules called prebiotics are known to benefit human health by stimulating the growth and activity of probiotic bacteria present in the intestinal microflora. The aim of this study was to evaluate how different oligosaccharides affect the growth and fatty acid profile of Lactobacillus plantarum (NRRL - B4496). L....
Tipo: Journal article
Palavras-chave: CLA; Fatty acid profile; Lactobacillus plantarum; Oligosaccharides.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400008

SSR genetic diversity assessment of popular pigeonpea varieties in Malawi reveals unique fingerprints
Provedor de dados: Electronic Journal of Biotechnology
Autores: Njung'e,Vincent; Deshpande,Santosh; Siambi,Moses; Jones,Richard; Silim,Said; De Villiers,Santie.
Background: Pigeonpea (Cajanus cajan (L.) Millsp.) is a drought tolerant legume of the Fabaceae family and the only cultivated species in the genus Cajanus. It is mainly cultivated in the semi-arid tropics of Asia and Oceania, Africa and America. In Malawi, it is grown as a source of food and income and for soil improvement in intercropping systems. However, varietal contamination due to natural outcrossing causes significant quality reduction and yield losses. In this study, 48 polymorphic SSR markers were used to assess the diversity among all pigeonpea varieties cultivated in Malawi to determine if a genetic fingerprint could be identified to distinguish the popular varieties. Results: A total of 212 alleles were observed with an average of 5.58 alleles...
Tipo: Journal article
Palavras-chave: Genetic variation; Genotyping; Microsatellites; Seed purity.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300008

Production of phenolic metabolites by Deschampsia antarctica shoots using UV-B treatments during cultivation in a photobioreactor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sequeida,Álvaro; Tapia,Eduardo; Ortega,Marcelo; Zamora,Pablo; Castro,Álvaro; Montes,Christian; Zúñiga,Gustavo E; Prieto,Humberto.
Deschampsia antarctica (DA), the only species in the Gramineae family endemic to the Antarctic territory, is characterized by a combination of high levels of free endogenous phenylpropanoid compounds under normal in situ and in vitro growth conditions. In this article, we describe the design and use of a specific temporary immersion photobioreactor to produce both increased DA biomass and secondary metabolite accumulation by UV-B elicitation during cultivation. Three min-long immersions in an induction medium applied every 4 hrs at 14ºC ± 1 and 20/4 hrs light/darkness photoperiod increased DA biomass production over previous in vitro reports. Biomass duplication was obtained at day 10.7 of culturing, and maximum total phenolics and antioxidant activity...
Tipo: Journal article
Palavras-chave: Deschampsia antarctica; Phenolic compounds; Temporary immersion bioreactor; UV-B elicitation.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000400008

Biotechnology and Development: A balance between IPR protection and benefit-sharing
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wendt,Jan; Izquierdo,Juan.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300001

Genetic diversity and population structure analysis of strawberry (Fragaria x ananassa Duch.) using SSR markers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yoon,Min-Young; Moe,Kyaw Thu; Kim,Dae-Young; Rho,Il-Rae; Kim,Su; Kim,Ki-Taek; Won,Mi-Kyoung; Chung,Jong-Wook; Park,Yong-Jin.
In total, 18 simple sequence repeat (SSR) markers were used to analyze the genetic diversity and population structure of 59 accessions of cultivated strawberry (Fragaria x ananassa Duch.) from Korea, Germany, United States, United Kingdom, and Japan. In total, 101 alleles were detected with an average of 5.6 per locus and 21 specific alleles were identified. Notably, one genotype (Blonoli from Germany) possessed a maximum of 10 different unique alleles specific to each genotype. The gene diversity varied from 0.027 (EMPaEKO1B) to 0.791 (CFACT110), with an average value of 0.509. PIC values ranged from 0.026 to 0.762 (average 0.454). A model-based structure analysis revealed the presence of two populations. The accessions that were clearly assigned to a...
Tipo: Journal article
Palavras-chave: Genetic diversity; Population structure; SSR markers; Strawberry.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000200006

Biosorption of hexavalent chromium using tamarind (Tamarindus indica) fruit shell-a comparative study
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rao Popuri,Srinivasa; Jammala,Ajithapriya; Naga Suresh Reddy,Kachireddy Venkata; Abburi,Krishnaiah.
The adsorption of chromium (VI) ions from aqueous solutions has been investigated on crude tamarind fruit shell, HCl treated and Oxalic acid treated shells at room temperatures. The biosorbents are characterized by FT-IR, EDXRF and porosimetry. The biosorption experiments are conducted through batch system. The influence of different experimental parameters such as pH, effect of initial metal ion concentration and effect of dosage of adsorbent on biosorption are evaluated. The adsorption followed first order kinetics. The data are fitted well to Langmuir and Freundlich isotherm models. A comparison is drawn on the extent of biosorption between untreated and treated forms of the tamarind shells. Due to their outstanding adsorption capacities, tamarind...
Tipo: Journal article
Palavras-chave: Biosorption; Chromium (VI); Pre-treatment; Tamarindus indica fruit shell.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300003

Multiple gene knock-down by a single lentiviral vector expressing an array of short hairpin RNAs
Provedor de dados: Electronic Journal of Biotechnology
Autores: Stove,Veronique; Smits,Kaatje; Naessens,Evelien; Plum,Jean; Verhasselt,Bruno.
RNA interference (RNAi), mediated by short double-stranded RNAs, is a powerful mechanism for posttranscriptional gene silencing. Sustained expression of short hairpin RNA (shRNA) can be accomplished in mammalian cells by viral delivery systems. Using lentiviral constructs, stable gene silencing is established both in dividing and non-dividing cells. Targeting one single gene can lead to the development of escape mutants or may be insufficient to silence redundant pathways. Therefore, simultaneous targeting of multiple genes may be necessary. We have generated a lentiviral vector-based system for expression of multiple shRNAs from a single viral vector, which also encodes an EGFP reporter protein. We show that knock-down of each single gene from multiple...
Tipo: Journal article
Palavras-chave: EGFP; Lentiviral gene transfer; Multiple knock-down; RNAi; Rho GTPases; ShRNA.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500013

Latin American Genome Initiative, the Creation of a Network and Web Based Resource to Aid and Nurture Genome Biology in Developing Countries
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ramírez,Jose Luis; González,Alicia; Cantú,José María; Chavez-Crooker,Pamela; Leiva,Juan Carlos; Blamey,Jenny M.; Cortes,Hernan; Holmes,David.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300002

Viability of probiotic bacteria and some chemical and sensory characteristics in cornelian cherry juice during cold storage
Provedor de dados: Electronic Journal of Biotechnology
Autores: Nematollahia,Amene; Sohrabvandi,Sara; Mortazavian,Amir Mohammad; Jazaeri,Sahar.
Background: Increased popularity of vegetarianism, lactose intolerance, and the high cholesterol content in dairy products, are all factors that have recently increased the demand for nondairy probiotic products. The objective of this study is to evaluate the effect of refrigeration on the viability of probiotics and asses some of the chemical and sensory characteristics in cornelian cherry juice. Results: The Iranian native probiotic strain (L. casei T4) showed greater viability compared to industrial types (viable count of 8.67 log cfu/mL versus &lt;6.0 log cfu/mL at d 28). However, this most tolerant Iranian strain, could not withstand the conditions of 'Natural juice' at pH 2.6 for more than 7 d. Following a pH adjusted treatment (to pH ~3.5), the...
Tipo: Journal article
Palavras-chave: Antioxidant activity; Anthocyanin; Cornelian cherry; Phenolic compounds; Probiotic; Viability.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300005

Sorption kinetics of Pb2+ and Cu2+ ions from aqueous solution by Nipah palm (Nypa fruticans Wurmb) shoot biomass
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wankasi,Donbebe; Horsfall Jnr,Michael; Ibuteme Spiff,Ayabaemi.
The sorption kinetics of Pb2+ and Cu2+ ions in aqueous solution by unmodified and mercaptoacetic acid modified biomass of Nypa fruticans shoot has been investigated. The equilibrium sorption capacity of Pb2+ and Cu2+ was determined from the Langmuir equation and found to be 15.59 mg/g and 21.85 mg/g for unmodified biomass and 52.86 mg/g and 66.71 mg/g for modified biomass at 30&amp;ordm;C. The time dependent studies showed relatively rapid sorption of 5 - 10 min to reach equilibrium for both metal ions. A batch sorption model, based on the assumption of the pseudo-second-order mechanism, was applied to predict the rate constants (g mg-1 min-1), which were found to be 3.59 x 10-4 (Pb2+) and 1.85 x 10-4 (Cu2+) and 2.82 x 10-2 (Pb2+) and 3.67 x 10-2 (Cu2+) on...
Tipo: Journal article
Palavras-chave: Adsorption; Heavy metal binding; Nipah palm.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500015

Lipase production and growth modeling of a novel thermophilic bacterium: Aneurinibacillus thermoaerophilus strain AFNA
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ebrahimpour,Afshin; Rahman,Raja Noor Zaliha Raja Abd; Kamarudin,Nor Hafizah Ahmad; Basri,Mahiran; Salleh,Abu Bakar.
Aneurinibacillus thermoaerophilus strain AFNA as a novel isolated extracellular thermostable organic solvent tolerant lipase producing bacterium was employed in the present study. The lipase production of strain AFNA and its correlation with bacterial growth was studied via a modeling assessment by response surface methodology (RSM) and artificial neural network (ANN) techniques. The best achieved models were multilayer full feed forward incremental back propagation network and modified cubic response surface model (mRSM) using backward elimination. The highest lipase specific activity (13.1 Umg-1) and bacterial growth (OD600 = 3.0) were obtained at technically similar: growth temperature (53 and 53ºC), inoculum size (2.6 and 3.0%), agitation rate (118 and...
Tipo: Journal article
Palavras-chave: Artificial neural network; Modified response surface methodology; Thermostable; Organic solvent tolerant.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400006

Cultivation of Trichosporon mycotoxinivorans in sugarcane bagasse hemicellulosic hydrolyzate
Provedor de dados: Electronic Journal of Biotechnology
Autores: Matos,Ítalo Thiago Silveira Rocha; Cassa-Barbosa,Luciana Araújo; Neto,Pedro Queiroz Costa; Filho,Spartaco Astolfi.
Background: The yeast strain IB09 was isolated from the gut of Calosoma sp. (Carabidae, Coleoptera, Insecta) that were collected in the central Amazon rainforest. First, tolerance of the strain to ethanol and heat was tested. Then, IB09 was cultivated in a medium using sugarcane bagasse hemicellulosic hydrolyzate as a carbon source, and cell growth (OD600), specific growth rate (µMAX, h-1), biomass yield (Y B, g.g-1) and relative sugar consumption (RSC, %) were evaluated. Taxonomic identification was determined by sequencing the ITS1 region of IB09 and comparing it to sequences obtained from the GenBank database (NCBI). Results: IB09 showed both ethanol tolerance and thermotolerance. Relative sugar consumption indicated that IB09 was able to perform...
Tipo: Journal article
Palavras-chave: Amazon strain; Biomass production; Biotechnological potential; Saccharification.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000100002

The role of Mn++ ions for high and consistent yield of citric acid in recycling fed-batch bioreactor system and its novelty on kinetic basis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ali,Sikander; ul-Haq,Ikram; Iqbal,Javed.
The present investigation deals with a novel technique for high and consistent yield of citric acid in a fed-batch bioreactor of 9-L working volume. Five different potent cultures of Aspergillus niger were evaluated for citrate production using clarified cane-molasses as basal substrate. Among the cultures, NG GCB101 (developed by UV/chemical mutation in our labs) gave maximum production of citric acid i.e., 87.98 g/l after 6 days of mycelial inoculation. The values of kinetic parameters such as substrate consumption and product formation rates revealed the hyperproducibility of citric acid by selected Aspergillus niger NG GCB101 (LSD = 0.456, HS). The addition of MnSO4 to the culture medium promoted the formation of small rounded fluffy pellets (1.55 mm²,...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200005

Insecticidal effects of plant extracts on immature whitefly Bemisia tabaci Genn. (Hemiptera: Aleyroideae)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cruz-Estrada,Angel; Gamboa-Angulo,Marcela; Borges-Argáez,Rocío; Ruiz-Sánchez,Esaú.
Background: The whitefly (Bemisia tabaci Genn.) is a widely distributed and highly harmful plant pest species. The management of B. tabaci has been typically carried out by chemical pesticides. In the last decade however, there has been an increasing interest in natural products, particularly those of plant origin, to control this pest species. In the present work, aqueous and ethanolic extracts of native plants from the flora of the Yucatán peninsula (Acalypha gaumeri, Annona squamosa, Carlowrightia myriantha, Petiveria alliaceae and Trichilia arborea) and the introduced plant Azadirachta indica were collected and evaluated for insecticidal activity against eggs and nymphs Bemisia tabaci. Results: Most of the aqueous and ethanolic extracts showed high...
Tipo: Journal article
Palavras-chave: Annona squamosa; Bemisia tabaci; Botanical insecticides; Plant extracts; Petiveria alliaceae.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000100006

Molecular cloning and expression analysis of 12-oxophytodienoate reductase cDNA by wounding in Solanum tuberosum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Díaz,Mauricio; Polanco,Victor; Ramírez,Ingrid; Peña-Cortés,Hugo.
Jasmonic acid (JA) and 12-oxophytodienoic acid (OPDA) are signal molecules involved in the stress and defense responses in plants. A full-length cDNA clon of OPR3 encoding 12-oxophytodienoate reductase 3, key enzyme involved in the biosynthesis of JA from linolenic acid was obtained from a Solanum tuberosum cDNA library. Sequence analysis showed that OPR3 encoded a polypeptide of 400 amino acids with a predicted molecular mass of 43.9 kDa and pI of 7.72. The deduced amino acid sequence of OPR3 showed high similarities to other 12-oxophytodienoate reductases. A peroxisomal signal sequence indicates OPR3 probable location in peroxisome. Levels of OPR3 mRNA accumulated in potato leaves reaching maximum levels within 1 hr of mechanical wounding. Elevated...
Tipo: Journal article
Palavras-chave: 12-oxophytodienoate reductase; Jasmonic acid; OPDA; Solanum tuberosum; Stress; Wounding.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000100010

Isolation and characterization of the tissue and development-specific potato snakin-1 promoter inducible by temperature and wounding
Provedor de dados: Electronic Journal of Biotechnology
Autores: Almasia,Natalia I; Narhirñak,Vanesa; Hopp,H. Esteban; Vazquez-Rovere,Cecilia.
Snakin-1 (StSN1) is a broad-spectrum antimicrobial peptide isolated from Solanum tuberosum. Homologous proteins have been identified in a wide range of species but there is no apparent consensus in the roles they play. A 1394 bp fragment of the 5&amp;#8217;upstream region of StSN1 gene, designated PStSN1, was isolated from the potato genome and sequenced. Bioinformatics analyses revealed a total of 55 potential regulatory motifs related to tissue-specificity, stress, defence and hormone responsiveness, among others. PStSN1 spatial and temporal activity was studied in transgenic Arabidopsis plants expressing a reporter gene under this promoter control (PStSN1::GUS). Histochemical staining revealed PStSN1::GUS expression in the root vasculature, cotyledons,...
Tipo: Journal article
Palavras-chave: Antimicrobial peptide; Inducible promoter; Potato; Snakin/GASA.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500008

Expression of bacterial genes in transgenic tobacco: methods, applications and future prospects
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jube,Sandro; Borthakur,Dulal.
Tobacco is the most commonly used plant for expression of transgenes from a variety of organisms, because it is easily grown and transformed, it provides abundant amounts of fresh tissue and has a well-established cell culture system. Many bacterial proteins involved in the synthesis of commercial products are currently engineered for production in tobacco. Bacterial enzymes synthesized in tobacco can enhance protection against abiotic stresses and diseases, and provide a system to test applied strategies such as phytoremediation. Examples of bacterial gene expression in tobacco include production of antigen proteins from several human bacterial pathogens as vaccines, bacterial proteins for enhancing resistance against insects, pathogens and herbicides,...
Tipo: Journal article
Palavras-chave: Biotechnology; Environmental stress; Insect/pathogen/herbicide resistance; Phytoremediation; Transgenics; Vaccine production.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300013

Supercritical fluid CO2 extraction of essential oil from Marchantia convoluta: global yields and extract chemical composition
Provedor de dados: Electronic Journal of Biotechnology
Autores: Xiao,Jian Bo; Chen,Jing Wen; Xu,Ming.
The essential oil of Marchantia convoluta was obtained by supercritical (carbon dioxide) extraction using methanol as a modifier. Global yields were determined according to the orthogonal design. The effects of different parameters, such as pressure, temperature, modifier volume and extraction time, on the supercritical fluid extraction (SFE) of essential oil from M. convoluta were investigated. Maximum global yields were obtained using the following conditions: extraction temperature, 35ºC; dynamic time, 35 min; pressure, 15 Mpa and modifier volume, 40 mL. The essential oil extract was analyzed by capillary gas chromatography with mass spectrometric detector (GC-MS). The compounds were identified according to their retention indices and mass spectra (EI,...
Tipo: Journal article
Palavras-chave: GC-MS; Supercritical fluid extraction; Yields.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100013

Rapid automated selection of mammalian cell line secreting high level of humanized monoclonal antibody using Clone Pix FL system and the correlation between exterior median intensity and antibody productivity
Provedor de dados: Electronic Journal of Biotechnology
Autores: Dharshanan,Suba; Chong,Heilly; Hung,Cheah Swee; Zamrod,Zulkeflie; Kamal,Nazlee.
The selection of high-producing mammalian cell lines is a crucial step in process development for the production of biopharmaceuticals. Previously, cloning by limiting dilution method was used to isolate monoclonal NS0 cells secreting high levels of humanized-C2 monoclonal antibodies. However limiting dilution method is time consuming, has low probability of monoclonality and is significantly limited by the number of clones that can be feasibly screened. In order to minimize the duration and to increase the probability of obtaining high-producing clones with high monoclonality, an automated colony picker, Clone Pix FL system was used to replace limiting dilution method. We were able to screen 1 x 10(5) clones secreting humanized monoclonal antibodies and...
Tipo: Journal article
Palavras-chave: Cancer immunotherapy; High producer cell line; High-throughput selection; NS0 cells; Semi-solid media.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200008

Oxygen and temperature effect on continuous citric acid secretion in Candida oleophila
Provedor de dados: Electronic Journal of Biotechnology
Autores: Anastassiadis,Savas; Rehm,Hans-Jürgen.
The influence of air saturation and temperature on continuous citric acid secretion was studied in chemostat cultures of Candida oleophila ATCC 20177 (var.). Simultaneous measurements of intra- and extracellular concentration of glucose, citric and isocitric acid confirmed the involvement of a specific active transport system in citrate secretion, favouring citric acid over isocitrate. An optimum air oxygen saturation of 20% and temperature of 30-31&amp;ordm;C were determined for the continuous citric acid secretion. The highest values of citric acid concentration (98 g/L), citrate to isocitrate ratio (33.3:1), volumetric citric productivity (1.8 g/(L x h)), and specific citric acid productivity (0.1 g/(g x h)), were reached at 20% air saturation at a...
Tipo: Journal article
Palavras-chave: Candida oleophila; Citric acid; Citric acid secretion.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400010

Measuring b-Galactosidase activity at pH 6 with a differential pH sensor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Acevedo,Cristian; Stach,Matthias H; Amtmann,Anette; Young,Manuel E; Reyes,Juan G; Huebner,Holger; Buchholz,Rainer.
The b-Galactosidase activity at pH 6 is used as a cellular marker to identify senescent cell cultures. The classic method to identify this enzymatic activity is using cytochemical staining with X-Gal after 16 hrs. In this work, a differential pH sensor was used to measure b-Galactosidase activity at pH 6. The measurement is easy and only takes 3 min.
Tipo: Journal article
Palavras-chave: B-Galactosidase; Delta milli pH; Differential pH.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200012

Isolation and regeneration of transiently transformed protoplasts from gametophytic blades of the marine red alga Porphyra yezoensis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Takahashi,Megumu; Uji,Toshiki; Saga,Naotsune; Mikami,Koji.
Despite the recent progress of transient gene expression systems in a red alga Porphyra yezoensis by particle bombardment, a stable transformation system has yet to establish in any marine red macrophytes. One of the reasons of the difficulty in genetic transformation in red algae is the lack of systems to select and isolate transformed cells from gametophytic blades. Thus, toward the establishment of the stable transformation system in P. yezoensis, we have developed a procedure by which transiently transformed gametophytic cells were prepared from particle bombarded-gametophytic blade as regeneratable protoplasts. Using mixture of marine bacterial enzymes, yield of protoplasts was high as reported elsewhere; however, these protoplasts did not develop. In...
Tipo: Journal article
Palavras-chave: Allantoin; Protoplast; P. yezoensis; Regeneration; Transient gene expression.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000200008

Isolation and study of a ubiquitously expressed tomato pectin methylesterase regulatory region
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tiznado-Hernández,Martín-Ernesto; Gaffe,Joel; Handa,Avtar K.
Pectin methylesterase (PME) is an enzyme located in the plant cell wall of higher plants whose physiological role is largely unknown. We had isolated a PME gene from a tomato genomic library, including 2.59 kb of 5´ flanking region and the coding region. Both coding and promoter region were sequenced and computer analyzed. Tobacco transgenic plants were created harboring constructs in which 2.596 Kb, 1.306 Kb and 0.267 Kb sizes of the promoter were driving the expression of &amp;#946;-Glucuronidase gene (GUS). GUS activity was studied by histochemical and fluorometric assays. Two introns of 106 and 1039 bp were found in the coding region and phylogenetic analysis placed this PME gene closer to genes from Citrus sinensis and Arabidopsis thaliana than tomato...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000100004

Expression analysis of vasa in Asian paddle crab (Charybdis japónica) exposed to Bisphenol A
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chen,Jianhua; Wang,Cuihua; Gao,Huan; Yan,Binlun.
Background: Bisphenol A (BPA) is an endocrine-disrupting chemical (EDC) with a weak estrogen-like activity in fish that is found ubiquitously in aquatic environments. However, there has been little study about BPA on the endocrine disrupting effects of crab. In the present study, cDNA of vasa was cloned and characterized in the Charybdis japonica. Histological structures of testis and expression patterns of vasa gene in the testis of C. japonica after treatment with BPA were investigated. Results: The cDNA of vasa is composed of 3051 bp with a 2166 bp open reading frame encoding 721 AA. The deduced amino acid sequence contained eight conserved domains of the DEAD-box protein family. The tissue distribution showed that vasa mRNA was specifically expressed...
Tipo: Journal article
Palavras-chave: Aquatic environments; BPA; DEAD-box; Endocrine disrupting; Expression analysis; Expression patterns; Histological observation; Vasa; Vasa cDNA; Vasa gene; Vasa mRNA.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600008

Biohydrogen production by Thermoanaerobacterium thermosaccharolyticum KKU-ED1: Culture conditions optimization using mixed xylose/arabinose as substrate
Provedor de dados: Electronic Journal of Biotechnology
Autores: Saripan,Arunsri Fangkum; Reungsang,Alissara.
Background: Biological hydrogen production by microorganisms can be divided into two main categories i.e. photosynthetic organisms that produce hydrogen using light as energy source and anaerobic bacteria that produce hydrogen via dark fermentation. Dark fermentative hydrogen production by anaerobic bacteria has the advantages of a higher HPR without illumination and of the capability to convert various kinds of substrate. Results: Thermophilic hydrogen producer was isolated from elephant dung and identified as Thermoanaerobacterium thermosaccharolyticum KKU-ED1 by 16S rRNA gene analysis, which was further used to produce hydrogen from mixed pentose sugar i.e., xylose/arabinose. The optimum conditions for hydrogen production from mixed xylose/arabinose by...
Tipo: Journal article
Palavras-chave: Arabinose; Biohydrogen; Elephant dung; Hydrolysate; Thermophilic; Xylose.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000100001

Comment on 'An evaluation of copper biosorption by a brown seaweed under optimized conditions' by Antunes, W.M., Luna, A.S., Henriques, C.A. and da Costa, A.C.A.
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ho,Yuh-Shan.
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200011

Heterologous expression, purification and refolding of an anti-listerial peptide produced by Pediococcus acidilactici K7
Provedor de dados: Electronic Journal of Biotechnology
Autores: Halami,Prakash M; Chandrashekar,Arun.
The fusion protein, 6XHis-Xpress-PedA was constructed and expressed in Escherichia coli BL21 (DE3). The presence of a 12.8 kDa recombinant protein, localized in inclusion bodies (IBs) at high concentration, was confirmed by SDS-PAGE analysis and by western blotting using anti-His antibody. The rec-pediocin was purified by Nickel-nitrilotriacetic acid beads and refolded using 5 mM of &amp;#946;-mercaptoethanol along with 1 M glycine. Results indicated that the refolded rec-pediocin had an early elution profile in the RP-HPLC when compared to the unfolded protein and it exhibited biological activity against Listeria monocytogenes V7 which was approximately 25 times less active compared to native counterpart. The final yield of purified rec-pediocin was 3...
Tipo: Journal article
Palavras-chave: Fusion protein; Inclusion bodies; In vitro refolding; Pediocin PA-1; Pediococcus acidilactici; RP-HPLC.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000400009

The effect of three plant bioregulators on pollen germination, pollen tube growth and fruit set in almond [Prunus dulcis (Mill.) D.A. Webb] cvs. Non Pareil and Carmel
Provedor de dados: Electronic Journal of Biotechnology
Autores: Maita,Segundo; Sotomayor,Carlos.
Background In commercial almond [Prunus dulcis (Mill.) D.A. Webb] orchards in Chile, the percentage of fruit set is low and commonly reaches 5–30%. As almond trees bloom during a cool period and also suffer from self-incompatibility, any factor that can improve pollination, pollen germination and pollen tube growth or extend the effective pollination period, such as the application of plant bioregulators (PBRs), should be beneficial for fruit production. Results Three plant bioregulators (PBRs): brassinolide (BL), gibberellic acid (GA3) and kinetin (KN) were evaluated for pollen germination and pollen tube growth in vitro, as well as for fruit set in almond cultivars Non Pareil and Carmel, in central Chile, during the 2013 and 2014 seasons. For pollen...
Tipo: Journal article
Palavras-chave: Fruit set; Plant bioregulators; Pollen germination; Pollen tube growth; Prunus dulcis.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500010

Determination of fructan exohydrolase activity in the crude extracts of plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Krivorotova,Tatjana; Sereikaite,Jolanta.
Background The roots of chicory and the tubers of Jerusalem artichoke are used for the production of inulin. However, a quality of tubers and roots, i.e. the content of inulin, monosaccarides and disaccharides, depends on the activity of enzymes implicated in the metabolism of inulin. The knowledge on the changes of activities of inulin synthesizing and degrading enzymes is limited during plant sprouting, growth and dormancy. It happens due to complicated measurements of the product of enzymatic reaction in the presence of crude plant extract. Fructan exohydrolase (&amp;#946;-d-fructan fructohydrolase, FEH, EC 3.2.1.80) is an enzyme responsible for the hydrolysis of fructans in plants. For fructose as the reaction product measurement, a high-performance...
Tipo: Journal article
Palavras-chave: 3; 5-Dinitrosalicylic acid Copper(II)-neocuproine Enzymatic method Fructose determination.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000600012

Aerobic removal of stigmasterol contained in kraft mill effluents
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chamorro,Soledad; Xavier,Claudia Regina; Hernández,Victor; Becerra,José; Vidal,Gladys.
Kraft mill effluent, due to its organic matter content and acute toxicity, must be treated. A primary treatment followed by a secondary treatment is the most common system. Aerated lagoon is also considered an effective biological treatment, although this technology has some drawbacks related with operation parameters and land extension space. Moreover, the recovery efficiency for micropollutants contained in kraft mill effluent is questioned due to the anoxic zone in the system. The goal of this work is to evaluate the performance of the aerated lagoon to remove stigmasterol contained in kraft mill effluents. Kraft mill effluent was treated by an aerated lagoon (AL), which was operated with three different stigmasterol load rates (SLR = 0.2, 0.6 and 1.1...
Tipo: Journal article
Palavras-chave: Aerated lagoon; Kraft mill effluent; Stigmasterol.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200001

The relationship among knowledge of, attitudes toward and acceptance of genetically modified organisms (GMOs) among Slovenian teachers
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sorgo,Andrej; Ambrozis-Dolinsek,Jana.
The objective of this study was to investigate knowledge about, opinions on and attitudes toward and finally readiness to accept genetically modified organisms (GMO) among Slovenian teachers. On average, they have higher levels of knowledge in classical genetics, and poor levels of knowledge about modern issues in biotechnology, and their attitudes toward GMOs are not extreme. They make decisions based on the acceptability of a particular GMO and not on GMOs in general, following two patterns: genetic modifications (GM) microorganisms and plants are more acceptable than animals, and GMOs are more acceptable if they can not be used directly for consumption and produce something recognized as useful. The relationship among knowledge of, attitudes towards and...
Tipo: Journal article
Palavras-chave: Acceptance; Attitudes; Biotechnology; Education; Genetically modified organisms; Knowledge.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400001

Production of cold-adapted cellulase by Verticillium sp. isolated from Antarctic soils
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Nengfei; Zang,Jiaye; Ming,Kaili; Liu,Yu; Wu,Zuohao; Ding,Hui.
Background: Cellulose can be converted to ethanol by simultaneous saccharification and fermentation (SSF). The difference between the optimal temperature of cellulase and microbial fermentation, however, has been identified as the critical problem with SSF. In this study, one fungal strain (AnsX1) with high cellulase activity at low temperature was isolated from Antarctic soils and identified as Verticillium sp. by morphological and molecular analyses. Results: The biochemical properties of crude AnsX1 cellulase samples were studied by filter paper cellulase assay. The maximum cellulase activity was achieved at low temperature in an acidic environment with addition of metal ions. Furthermore, AnsX1 cellulase demonstrated 54-63% enzymatic activity at...
Tipo: Journal article
Palavras-chave: Antarctic soil; Cellulose; Filter paper cellulase assay; Psychrotrophic fungi; Verticillium sp.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400010

Human sulfatase transiently and functionally active expressed in E. coli K12
Provedor de dados: Electronic Journal of Biotechnology
Autores: Poutou-Piñales,Raúl A; Vanegas Niño,Adriana; Landázuri,Patricia; Sáenz,Homero; Lareo,Leonardo; Echeverri Peña,Olga Yaneth; Barrera Avellaneda,Luis A.
The recombinant human iduronate 2-sulfate sulfatase (hrIDS) was transiently and functionally active expressed in E. coli K12. The enzyme activity (crude extract) at 100 ml and 400 ml oscillated between 0.25 and 10.58 nmol h-1 mg-1. The wide Western-blot peptide profile suggest that hrIDS is proteolitically processed “randomly” which agrees with the ultrafiltration assay in which the hrIDS activity was found in all fractions (&lt;30kDa, 30-100kDa and &gt;100kDa). No glycation sites were found by computer analysis of the hIDS sequence; discarding the possibility of marks for glycation and proteolytic processing.
Tipo: Journal article
Palavras-chave: E. coli; Glycation; Human sulfatase; Transient expression.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300005

In vitro biocontrol activity of Trichoderma harzianum on Alternaria alternata in the presence of growth regulators
Provedor de dados: Electronic Journal of Biotechnology
Autores: Roco,Angela; Pérez,Luz María.
The in vitro biocontrol ability of Trichoderma harzianum on the phytopathogen Alternaria alternata improved in the presence of the growth regulators gibberellic acid (GA3), or indolacetic acid (IAA) or benzylaminopurine (BAP) or foliar nutrient at concentrations similar or higher than those used at the field level. These plant hormones decreased the secretion of endopolygalacturonase (endo-PG) of A. alternata by approximately 20%, did not modify endochitinase (endo-CH) secretion of T. harzianum and did not alter germination of conidia or mycelia growth of any of these fungi. The presence of T. harzianum decreased endo-PGase secretion of A. alternata by about 50%. This inhibitory effect was independent of the presence of growth regulators. The level of...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200006

Biosorption of chromium(III) by Sargassum sp. biomass
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sala Cossich,Eneida; Granhen Tavares,Célia Regina; Kakuta Ravagnani,Teresa Massako.
Chromium is present in different types of industrial effluents, being responsible for environmental pollution. Traditionally, the chromium removal is made by chemical precipitation. However, this method is not completely feasible to reduce the chromium concentration to levels as low as required by environmental legislation. Biosorption is a process in which solids of natural origin are employed for binding heavy metals. It is a promising alternative method to treat industrial effluents, mainly because of its low cost and high metal binding capacity. In this work the chromium biosorption process by Sargassum sp. seaweed biomass is studied. Sargassum sp. seaweed, which is abundant in the Brazilian coast, has been utilized with and without milling. The work...
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200008

Attitudes towards genomic: Research in four Latin American countries
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rodríguez Yunta,Eduardo; Valdebenito Herrera,Carolina; Misseroni,Adelio; Fernández Milla,Lautaro; Outomuro,Delia; Schiattino Lemus,Irene; Ferrer Lues,Marcela; Lolas Stepke,Fernando.
The present reflection refers to data obtained about the social representations of genomic research and its applications through interviews with legislators and lawyers, biomedical researchers and civilians and the review of scientific and legal literature in four Latin American countries: Argentine, Chile, Mexico and Peru. Several issues are addressed: little access to prevention and therapeutic methods, lack of equity in health benefits, commercialization of gene sequences through patents which leads to commercial exploitation of underdeveloped countries, the possibility of physical or psychological damage or genetic discrimination, the possibility of genetic modifications or abortion for eugenic reasons, the necessity of safeguarding confidentiality,...
Tipo: Journal article
Palavras-chave: Cloning; Genome; Social representations; Transgenic.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300003

Differences in the fly-load of Haematobia irritans (Diptera: Muscidae) on cattle is modified by endophyte infection of pastures
Provedor de dados: Electronic Journal of Biotechnology
Autores: Parra,Leonardo; Rojas,Claudio; Catrileo,Adrian; Galdames,Rafael; Mutis,Ana; Birkett,Michael A; Quiroz,Andrés.
Background: The horn fly, Haematobia irritans, is an obligate bloodsucking ectoparasite of pastured cattle and is a major pest of livestock production in North and South America and Europe. In this study, we investigated the potential to use cattle pastures, infected with non-toxic, "friendly" fungal-endophyte-infected (E+) tall fescue, Festuca arundinacea Schreb., as a strategy for reducing horn fly loads in cattle, and to evaluate the possible bioinsecticide effect on horn fly larvae. Results: When cattle grazed in E+ tall fescue, a decrease in fly-load was observed, compared with other pastures (endophyte-free (E-) pastures). The infestation of horn fly load decreased according to an increase in the percentage of endophyte present in the different...
Tipo: Journal article
Palavras-chave: Endophyte-infected tall fescue; Fly-load; Horn fly; Pasture.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500007

Improved calibration of a solid substrate fermentation model
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sacher,Johannes; Saa,Pedro; Cárcamo,Martín; López,Javiera; Gelmi,Claudio A; Pérez-Correa,Ricardo.
Background: Calibration of dynamic models in biotechnology is challenging. Kinetic models are usually complex and differential equations are highly coupled involving a large number of parameters. In addition, available measurements are scarce and infrequent, and some key variables are often non-measurable. Therefore, effective optimization and statistical analysis methods are crucial to achieve meaningful results. In this research, we apply a metaheuristic scatter search algorithm to calibrate a solid substrate cultivation model. Results: Even though scatter search has shown to be effective for calibrating difficult nonlinear models, we show here that a posteriori analysis can significantly improve the accuracy and reliability of the estimation....
Tipo: Journal article
Palavras-chave: Gibberella fujikuroi; Gibberellic acid; Global optimization; Metaheuristics; Nonlinear dynamic models; Parameter estimation; Solid substrate cultivation.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500007

Critical role of plant biotechnology for the genetic improvement of food crops: perspectives for the next millennium
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ortiz,Rodomiro.
This article reviews some of the highlights of modern plant biotechnology and discusses the potential applications of biotechnology in the betterment of farming systems in the next millennium. Plant biotechnology will facilitate the farming of crops with multiple durable resistance to pests and diseases, particularly in the absence of pesticides. Likewise, transgenes or marker-assisted selection may assist in the development of high yielding crops, which will be needed to feed the world and save land for the conservation of plant biodiversity in natural habitats. Hence, crops should be engineered to meet the demands and needs of consumers. The genetic base of crop production can be preserved and widen by an integration of biotechnology tools in...
Tipo: Journal article
Ano: 1998
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581998000300005

Statistical optimization of thermo-alkali stable xylanase production from Bacillus tequilensis strain ARMATI
Provedor de dados: Electronic Journal of Biotechnology
Autores: Khusro,Ameer; Kannan Kaliyan,Barathi; Abdullah Al-Dhabi,Naif; Valan Arasu,Mariadhas; Agastian,Paul.
Background: Xylanase from bacteria finds use in prebleaching process and bioconversion of lignocelluloses into feedstocks. The xylanolytic enzyme brings about the hydrolysis of complex biomolecules into simple monomer units. This study aims to optimize the cellulase-free xylanase production and cell biomass of Bacillus tequilensis strain ARMATI using response surface methodology (RSM). Results: Statistical screening of medium constituents and the physical factors affecting xylanase and biomass yield of the isolate were optimized by RSM using central composite design at N = 30, namely 30 experimental runs with 4 independent variables. The central composite design showed 3.7 fold and 1.5 fold increased xylanase production and biomass yield of the isolate...
Tipo: Journal article
Palavras-chave: Bacillus tequilensis; Biomass; Central composite design; RSM; Xylanase.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000400003

Marine Biotechnology Opportunities for Latin America
Provedor de dados: Electronic Journal of Biotechnology
Autores: Halvorson,Harlyn O.; Chavez-Crooker,Pamela; Diaz,Paula; Quezada,Fernando.
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200003

Continuous citric acid secretion by a high specific pH dependent active transport system in yeast Candida oleophila ATCC 20177
Provedor de dados: Electronic Journal of Biotechnology
Autores: Anastassiadis,Savas; Rehm,Hans-Jürgen.
The pH influence on continuous citric acid secretion was investigated in Candida oleophila ATCC 20177 (var.) under NH4+ limiting state steady conditions, using glucose. Highest citric acid concentration of 57.8 g/l, citrate/isocitrate ratio of 15.6, space-time yield of 0.96 g/(l x hr) and biomass specific productivity of 0.041 g/(g x hr) were obtained at pH 5 and 60 hrs residence time. Only 22.8 g/l (39.4%) and a ratio of 9.9 were achieved at pH 6 pH and 12.4 g/l (21.5%) and a ratio of 3.7 at pH 3. Under non producing conditions, in excess of nitrogen, biomass concentration increased at raising pH. An iron concentration of 200 ppm was determined in biomass of C. oleophila at pH 5, compared with only 26 ppm found at pH 3 (factor 7.7). Intra- and...
Tipo: Journal article
Palavras-chave: Active citrate export; Citric acid fermentation; Energy consuming citric acid secretion; Specific active transport system.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200004

One-step, codominant detection of imidazolinone resistance mutations in weedy rice (Oryza sativa L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rosas,Juan E; Bonnecarrère,Victoria; Pérez de Vida,Fernando.
Background Weedy rice (Oryza sativa L.) is a noxious form of cultivated rice (O. sativa L.) associated with intensive rice production and dry seeding. A cost-efficient strategy to control this weed is the Clearfield rice production system, which combines imidazolinone herbicides with mutant imidazolinone-resistant rice varieties. However, imidazolinone resistance mutations can be introgressed in weedy rice populations by natural outcrossing, reducing the life span of the Clearfield technology. Timely and accurate detection of imidazolinone resistance mutations in weedy rice may contribute to avoiding the multiplication and dispersion of resistant weeds and to protect the Clearfield system. Thus, highly sensitive and specific methods with high throughput...
Tipo: Journal article
Palavras-chave: Clearfield rice; DNA-based resistance diagnosis; Herbicide resistance; KASP; Red rice; SNP.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000200007

Biodegradation of natural phenolic compounds as single and mixed substrates by Fusarium flocciferum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Mendonça,Elsa; Martins,Aida; Anselmo,Ana Maria.
The mycelium of Fusarium flocciferum was assayed for its ability to degrade aromatic compounds, namely, gallic, protocatechuic, vanillic, syringic, caffeic, and ferulic acids and syringic aldehyde, commonly found in agro-industrial wastes. The biodegradation assays were performed in liquid medium with the phenolic compounds as single substrates and as a synthetic mixture containing the seven aromatic compounds. The results with single substrates indicated that in 24 hrs of incubation the fungus was able to reduce the phenolic concentration from 200 mg/l to below detection limits, except for syringic acid, being the lowest degradation rates found for this acid and its aldehyde. The biodegradation experiments with the mixture of phenolic compounds showed...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000100005

Micro-scale surface-patterning influences biofilm formation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kappell,Guimel M; Grover,James P; Chrzanowski,Thomas H.
The formation of biofilms on indwelling/implanted medical devices is a common problem. One of the approaches used to prevent biofilm formation on medical devices is to inhibit bacterial attachment by modification of the synthetic polymers used to fabricate the device. In this work, we assessed how micro-scale features (patterns) imprinted onto the surface of silicone elastomer similar to that used for medical applications influenced biofilm formation by Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa. Patterns were transferred from a multi-patterned oxidized silicon-wafer master-template to silicone elastomer. Features consisted of bars, squares, and circles each extending 0.51 µm above the surface. Feature sizes ranged...
Tipo: Journal article
Palavras-chave: Indwelling medical devices; Infections; Surface attachment.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300010

The effect of protective ingredients on the survival of immobilized cells of Streptococcus thermophilus to air and freeze-drying
Provedor de dados: Electronic Journal of Biotechnology
Autores: Champagne,Claude P.; Gardner,Nancy J.
Streptococcus thermophilus cultures were grown either on trehalose or lactose, immobilized in alginate beads, dipped in various protective solutions and dried by either convection air-drying (CAD) or freeze-drying (FD). Immobilized cultures dipped in the 0.1% peptone solution did not show good survival to CAD or FD, as mortality was over 99%. There was no significant difference in mortality levels, in both methods of drying, when lactose or trehalose were used as protective ingredients. The highest survival levels (50 to 98%) were with a whey-sucrose protective medium, but this was potentially related to a higher pH and solids of the solution. Mortality levels were higher in FD than CAD, and this did not appear to be related to the fact that FD cultures...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300009

Production of recombinant enzymes of wide use for research
Provedor de dados: Electronic Journal of Biotechnology
Autores: Manzur,María J.; Muñoz,Rosana V.; Lucero,Adrián A.; Juri Ayub,Maximiliano; Alvarez,Sergio E.; Ciuffo,Gladys M.
For biotechnological purposes, protein expression refers to the directed synthesis of large amounts of desired proteins. The aim of the present work was to produce reverse transcriptase Moloney murine Leukaemia Virus retro-transcriptase and Taq DNA polymerase, as bioactive products. In the present paper, we report the preparation of recombinant enzymes, expressed in E. coli strains. The enzymes produced exhibited quite good activity, compared with commercial enzymes, allowing us to replace the last ones for several lab applications. We are reporting changes and modifications to standard protocols described. The standard protocols were modified, i.e. for the purification step of Taq, a temperature dependent procedure was designed. The enzymes produced were...
Tipo: Journal article
Palavras-chave: Bioactivity; Protein expression; Purification; Recombinant enzymes.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300023

Comparison of shape analysis methods for Guinardia citricarpa ascospore characterization
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pazoti,Mário Augusto; Garcia,Rogério Eduardo; Cruz Pessoa,José Dalton; Martinez Bruno,Odemir.
Among the diseases affecting the commercial citrus production, the citrus black spot (CBS) is considered to cause substantial losses. The analyses of particles in suspension in the orchards and collected into a disc have been applied as a preventive action trying to identify the presence of fungus spores before symptom appearance. In this paper, we show the results of several shape analysis methods applied to the fungus, the first step to the aimed computer aided vision system, capable to assist the identification process. Experiments and comparative results among the methods are presented in this paper, showing that better results were obtained applying the curvature method
Tipo: Journal article
Palavras-chave: Computer vision; Curvature; Pattern recognition; Shape analysis; Shape signature and projection.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000300006

Lead biosorption onto waste beer yeast by-product: a means to decontaminate effluent generated from battery manufacturing industry
Provedor de dados: Electronic Journal of Biotechnology
Autores: Parvathi,Krishnakumar; Nagendran,Ramachandramurthy; Nareshkumar,Radhakrishnan.
This paper projects the potential of waste beer yeast Saccharomyces cerevisiae in biosorbing lead from battery manufacturing industrial effluent. Experiments were carried out as a function of pH, biosorbent concentration, lead concentration and agitation speed. Specific lead uptake of 2.34 mg/g was recorded and the data gave good fits for Freundlich and Langmuir models with Kf and Qmax values of 0.5149 and 55.71 mg/g. The roles played by amines, carboxylic acids, phosphates, sulfhydryl group and lipids in lead biosorption were studied. Electrostatic attraction may be the mechanism of biosorption. The extent of contribution of the functional groups and lipids to lead biosorption was in the order: carboxylic acids &gt; lipids &gt; amines &gt; phosphates....
Tipo: Journal article
Palavras-chave: Biosorption; Electrostatic attraction; Freundlich; Langmuir; Functional group; Lead; Yeast.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100009

Plumbagin production by root cultures of Plumbago rosea
Provedor de dados: Electronic Journal of Biotechnology
Autores: Panichayupakaranant,Pharkphoom; Tewtrakul,Supinya.
Root cultures of Plumbago rosea Linn. were established from young leaf explants on solid Gamborg's B5 (B5) medium supplemented with the combination of &lt;FONT FACE=Symbol&gt;á&lt;/FONT&gt;-naphthalene acetic acid (NAA) and kinetin in the concentration ranges of 0.5-2.0 mg/l and 0.1-0.5 mg/l, respectively. The production of plumbagin, determined by TLC-densitometry was higher [0.016 ± 0.0030% dry weight (DW)] in cultured roots obtained from B5 medium supplemented with 1.0 mg/l NAA and 0.1 mg/l kinetin. Plant selection increased the plumbagin production to 0.129 ± 0.0139% DW, while variation of sucrose and nitrogen (as (NH4)2SO4) concentration in B5 media slightly increase the plumbagin synthesis to 0.023 ± 0.0017 and 0.020 ± 0.0015% DW, respectively.
Tipo: Journal article
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000300006

Optimization of Bacillus subtilis cell growth effecting jiean-peptide production in fed batch fermentation using central composite design
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhong,Juan; Zhang,Xiaoyong; Ren,Yanli; Yang,Jie; Tan,Hong; Zhou,Jinyan.
Background Optimization of nutrient feeding was developed to improve the growth of Bacillus subtilis in fed batch fermentation to increase the production of jiean-peptide (JAA). A central composite design (CCD) was used to obtain a model describing the relationship between glucose, total nitrogen, and the maximum cell dry weight in the culture broth with fed batch fermentation in a 5 L fermentor. Results The results were analyzed using response surface methodology (RSM), and the optimized values of glucose and total nitrogen concentration were 30.70 g/L and 1.68 g/L in the culture, respectively. The highest cell dry weight was improved to 77.50 g/L in fed batch fermentation, which is 280% higher than the batch fermentation concentration (20.37 g/L). This...
Tipo: Journal article
Palavras-chave: Bacillus subtilis ZK8; Iturin A; Response surface methodology.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000300005

Buffering action of acetate on hydrogen production by Ethanoligenens harbinense B49
Provedor de dados: Electronic Journal of Biotechnology
Autores: Xu,Ji-Fei; Mi,Yuan-Ting; Ren,Nan-Qi.
The buffering effect of acetate on hydrogen production during glucose fermentation by Ethanoligenens harbinense B49 was investigated compared to phosphate, a widely used fermentative hydrogen production buffer. Specific concentrations of sodium acetate or phosphate were added to batch cultures, and the effects on hydrogen production were comparatively analyzed using a modified Gompertz model. Adding 50 mM acetate or phosphate suppressed the hydrogen production peak and slightly extended the lag phase. However, the overall hydrogen yields were 113.5 and 108.5 mmol/L, respectively, and the final pH was effectively controlled. Acetate buffered against hydrogen production more effectively than did phosphate, promoting cell growth and preventing decreased pH....
Tipo: Journal article
Palavras-chave: Acetate; Biohydrogen; Buffering action; Ethanoligenens harbinense phosphate.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500002

Statistical optimization for tannase production by Aspergillus tubingensis in solid-state fermentation using tea stalks
Provedor de dados: Electronic Journal of Biotechnology
Autores: Xiao,Anfeng; Huang,Yufeng; Ni,Hui; Cai,Huinong; Yang,Qiuming.
Background A sequential statistical strategy was used to optimize tannase production from Aspergillus tubingensis using tea stalks by solid-state fermentation. Results First, using a Plackett-Burman design, inoculum size and incubation time (among seven tested variables) were identified as the most significant factors for tannase yield. The effects of significant variables were further evaluated through a single steepest ascent experiment and central composite design with response surface analysis. Under optimal conditions, the experimental value of 84.24 units per gram of dry substrate (U/gds) closely matched the predicted value of 87.26 U/gds. Conclusions The result of the statistical approach was 2.09 times higher than the basal medium (40.22 U/gds)....
Tipo: Journal article
Palavras-chave: Aspergillus tubingensis; Process optimization; Response surface methodology; Tea stalks; Tannase fermentation.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300001

Arbuscular mycorrhiza-like biotechnological potential of Piriformospora indica, which promotes the growth of Adhatoda vasica Nees
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rai,Mahendra; Varma,Ajit.
We report the growth promoting potential of Piriformospora indica, which is a newly discovered arbuscular mycorrhiza-like fungus. It is a facultative symbiont and unlike arbuscular mycorrhizal fungi, it can be cultured in vitro. Adhatoda vasica is a medicinal plant. Rapid proliferation of roots was recorded in A. vasica withan important root colonization estimated to 95% after 6 months. P. indica improved growth of A. vasica. This association forms a new host-symbiont combination
Tipo: Journal article
Palavras-chave: Adhatoda vasica; Arbuscular mycorrhiza-like; Biotechnological potential; Growth promotion; Piriformospora indica.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000100013

The lift pool method for isolation of cDNA clones from lambda phage libraries
Provedor de dados: Electronic Journal of Biotechnology
Autores: LeBlanc-Straceski,Janine; Sobrado,Pablo; Betz,Sharon; Zerfas,Julie; Morgan,Karen.
A PCR based strategy was developed to screen a Xenopus oocyte &amp;lambda;gt10 cDNA library. The PCR-based lift pool (LP) method follows the same two tiered strategy as conventional screening of phage libraries by filter hybridization. Two rounds of plating, one at high density to detect the clone, and one at low density to purify the clone to homogeneity, are performed. In the first round, lysates from high density plates, termed plate pools (PP), serve as template for PCR. In the second round, phage particles adhering to plaque lifts of low density plates are washed off nitrocellulose filters to create LPs, which are used as template for PCR. The integrity of the plaques on the low-density plates is preserved. Once a positive LP has been identified,...
Tipo: Journal article
Palavras-chave: CDNA; Lambda; Non-radioactive; PCR; Plaque; Screening.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000400012

Effect of malate on docosahexaenoic acid production from Schizochytrium sp. B4D1
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhanga,Yong; Min,Qingsong; Xu,Jian; Zhang,Ke; Chen,Shulin; Wang,Haijun; Li,Demao.
Background: Malate involves in the citrate/malate and transhydrogenase cycles to provide precursors for docosahexaenoic acid (DHA) synthesis. The optimal strategy was investigated for increasing DHA production in Schizochytrium species during fermentation. Results: DHA production increased by 47% and reached 5.51 g/L when 4 g malate/L was added during the rapid lipid accumulation stage in shake-flasks culture. Inducing effects of malate was further investigated through the analysis of three kinetic parameters, including specificcell growth rate(&amp;#956;), specific glucose consumption rate (qGlu)and DHA formation rate (qDHA). DHA concentration was enhanced through a novel fed-batch strategy to a maximum value of 30.7 g/L, giving a yield of 0.103 g DHA/g...
Tipo: Journal article
Palavras-chave: DHA; Malate; NADPH; Schizochytrium sp.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000100009

Fast and reliable calibration of solid substrate fermentation kinetic models using advanced non-linear programming techniques
Provedor de dados: Electronic Journal of Biotechnology
Autores: Araya,M. Macarena; Arrieta,Juan J; Pérez-Correa,J. Ricardo; Biegler,Lorenz T; Jorquera,Héctor.
Calibration of mechanistic kinetic models describing microorganism growth and secondary metabolite production on solid substrates is difficult due to model complexity given the sheer number of parameters needing to be estimated and violation of standard conditions of numerical regularity. We show how advanced non-linear programming techniques can be applied to achieve fast and reliable calibration of a complex kinetic model describing growth of Gibberella fujikuroi and production of gibberellic acid on an inert solid support in glass columns. Experimental culture data was obtained under different temperature and water activity conditions. Model differential equations were discretized using orthogonal collocations on finite elements while model calibration...
Tipo: Journal article
Palavras-chave: Dynamic models; Gibberellic acid; Nonlinear models; Parameter estimation; Secondary metabolites; Solid substrate cultivation.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000100005

Gene expression of specific enological traits in wine fermentation
Provedor de dados: Electronic Journal of Biotechnology
Autores: Martínez,Claudio; García,Verónica; González,David; Jara,Matías; Aguilera,Matías; Ganga,Maria Angélica.
Background: Wine fermentation is a dynamic process and yeast has a precise genic regulation system that allow them to coordinate the gene transcription levels. However, the fermentation stage at which there is a great variation in the genic expression associated to a particular enological trait is often unknown and there are no simple experimental approaches to define it. Results: To identify the most adequate stage in which to evaluate the expression of the genes associated to specific enological traits we identified three stages of fermentation using the industrial strain EC1118. These stages, called early (0-16.4 hrs), middle (16.4-88.7 hrs) and late (88.7 hrs onwards), were characterized according to changes in the speed of CO2 production. The greatest...
Tipo: Journal article
Palavras-chave: Enological traits; Gene expression; Saccharomyces cerevisiae; Wine fermentation; Wine yeast.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400013

Isolation and characterization of a novel (S)-canadine synthase gene from Coptis chinensis
Provedor de dados: Electronic Journal of Biotechnology
Autores: He,Yang; Hou,Pei; Fan,Gang; Li,Dongmei; Peng,Cheng.
Background Berberine acts primarily as an important active ingredient in Coptis chinensis and has been traditionally applied in clinical treatment. Nevertheless, little information has been released about C. chinensis, as far as functional genes and biosynthetic pathway of berberine are concerned. Here, we isolated a novel (S)-canadine synthase gene (designated as CAS-1) from C. chinensis by using RT-PCR and RACE techniques. Results Bioinformatics analysis showed that the cDNA is 1942 bp in length with a complete open reading frame (ORF) of 1476 bp, and the ORF encodes a polypeptide of 491 amino acids with a calculated molecular mass of 55.29 kDa and a pI value of 8.92. Real-time quantitative PCR analysis showed that CcCAS-1 was constitutively expressed in...
Tipo: Journal article
Palavras-chave: Berberine biosynthesis; Coptis chinensis; Expression pattern.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000500009

RestrictionDigest: A powerful Perl module for simulating genomic restriction digests
Provedor de dados: Electronic Journal of Biotechnology
Autores: Wang,Jinpeng; Li,Li; Qi,Haigang; Du,Xuedi; Zhang,Guofan.
Background: Reduced-representation sequencing technology is widely used in genotyping for its economical and efficient features. A popular way to construct the reduced-representation sequencing libraries is to digest the genomic DNA with restriction enzymes. A key factor of this method is to determine the restriction enzyme(s). But there are few computer programs which can evaluate the usability of restriction enzymes in reduced-representation sequencing. SimRAD is an R package which can simulate the digestion of DNA sequence by restriction enzymes and return enzyme loci number as well as fragment number. But for linkage mapping analysis, enzyme loci distribution is also an important factor to evaluate the enzyme. For phylogenetic studies, comparison of...
Tipo: Journal article
Palavras-chave: Genotyping; Reduced-representation libraries; Reduced-representation sequencing.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000300003

Convenient genotyping of nine bovine K-casein variants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pacheco Contreras,Víctor I; Lourenco Jaramillo,Diana L; Parra Bracamonte,Gaspar M; Martínez González,Juan C; Sifuentes Rincón,Ana M.
K-casein gene polymorphisms are of major importance in the dairy industry due to their association with different quality and productive traits (i.e., milk protein). Several methods for genotyping this gene have been proposed; however, none are focused on the simultaneous discrimination of nine K-casein variants. A strategy based on PCR-RFLP was designed to characterize nine K-casein variants (A, B, C, E, F², G, H, I and J) and used to genotype three cattle populations: Gyrholando (3/8 Gyr x 5/8 Holstein), Charolais and Carora. The B variant was the most frequent in the Charolais and Carora breeds, with allelic frequencies of 0.60 and 0.59, respectively. In the Gyrholando breed, four variants were found, with the A variant being the most frequent and E and...
Tipo: Journal article
Palavras-chave: Milk proteins; Milk quality; Protein genes.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400012

Enhancement of ligninolytic enzyme activities in a Trametes maxima-Paecilomyces carneus co-culture: Key factors revealed after screening using a Plackett-Burman experimental design
Provedor de dados: Electronic Journal of Biotechnology
Autores: Chan Cupul,Wilberth; Heredia Abarca,Gabriela; Martínez Carrera,Daniel; Rodríguez Vázquez,Refugio.
Background In the industrial biotechnology, ligninolytic enzymes are produced by single fungal strains. Experimental evidence suggests that co-culture of ligninolytic fungi and filamentous microfungi results in an increase laccase activity. In this topic, only the ascomycete Trichoderma spp. has been studied broadly. However, fungal ligninolytic-filamentous microfungi biodiversity interaction in nature is abundant and poorly studied. The enhancement of laccase and manganese peroxidase (MnP) activities of Trametes maxima as a function of time inoculation of Paecilomyces carneus and under several culture conditions using Plackett-Burman experimental design (PBED) were investigated. Results The highest increases of laccase (12,382.5 U/mg protein) and MnP...
Tipo: Journal article
Palavras-chave: Enzyme activity enhance; Fungal interaction; Paecilomyces carneus; Time inoculation; White-rot fungi.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000300002

Accommodating the difference in students' prior knowledge of cell growth kinetics
Provedor de dados: Electronic Journal of Biotechnology
Autores: Seters,Janneke van; Ossevoort,Miriam; Goedhart,Martin; Tramper,Johannes.
This paper describes the development and benefits of an adaptive digital module on cell growth to tackle the problem of educating a heterogeneous group of students at the beginning of an undergraduate course on process engineering. Aim of the digital module is to provide students with the minimal level of knowledge on cell growth kinetics they need to comprehend the content knowledge of the subsequent lectures and pass the exam. The module was organised to offer the subject matter in a differentiated manner, so that students could follow different learning paths. Two student groups were investigated, one consisting of students who had received their prior education abroad and one of students that had not. Exam scores, questionnaires, and logged user data...
Tipo: Journal article
Palavras-chave: Adaptive digital learning material; Bioreactor design; Biotechnology; Education; Intelligent tutoring system; Intelligent Web-based educational system.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200001

Influence of medium constituents on the biosynthesis of cephalosporin-C
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kumar Nigam,Vinod; Verma,Ruchi; Kumar,Abhishek; Kundu,Subir; Ghosh,Purnendu.
Acremonium chrysogenum NCIM 1069 was used for the biosynthesis of cephalosporin-C (CPC) in batch mode of cultivation. The effect of different medium constituents for better yield of CPC was thoroughly investigated. From the results of the fermentation, it was found that ammonium sulphate as inorganic nitrogen source and methionine at the concentration of 0.4% are most suitable for higher yield of antibiotic. The variation in the C/N ratio on the biosynthesis of CPC showed that a C/N ratio of 8.0 is most suitable for maximum production of CPC
Tipo: Journal article
Palavras-chave: Acremonium chrysogenum; Batch fermentation; Cephalosporin-C; Methionine; Stirred tank bioreactor.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200007

Ethylene treatment improves diosgenin accumulation in in vitro cultures of Dioscorea zingiberensis via up-regulation of CAS and HMGR gene expression
Provedor de dados: Electronic Journal of Biotechnology
Autores: Diarra,Sabake T; He,Ji; Wang,Jianbo; Li,Jiaru.
Background: The perennial medicinal herb Dioscorea zingiberensis is a very important plant used for steroid drug manufacturing for its high level of diosgenin in rhizome. Although the stimulation of diosgenin accumulation by ethylene has been reported in a few of plant species, its regulation is not yet characterized at the molecular level, the underlying molecular mechanism remains elusive. Results: In this study, the effects of ethylene on diosgenin biosynthesis in in vitro cultures of D. zingiberensis were described. The results showed that, in samples treated with ethylene at concentration E3 (10(4) dilution of 40% ethephon), the diosgenin biosynthesis was significantly promoted in comparison with the control samples. Treatment with high concentrations...
Tipo: Journal article
Palavras-chave: Diosgenin; Dioscorea zingiberensis; Ethylene; Gene expression.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500006

Heat identification by 17&amp;#946;-estradiol and progesterone quantification in individual raw milk samples by enzyme immunoassay
Provedor de dados: Electronic Journal of Biotechnology
Autores: Domènech,Anna; Pich,Sara; Arís,Anna; Plasencia,Carmen; Bach,Alex; Serrano,Alicia.
Background: There is a substantial decline in first-service-pregnancy-rate in dairy cows. In this regard, future prospects are to measure milk hormones on-farm and progesterone levels in milk are not enough to precise ovulation unless connected to other data. The objectives of this study were to investigate whether 17&amp;#946;-estradiol could be measured from individual cow milk samples using a commercially available non-radiolabelled enzyme immunoassay kit (EIA) with no previously reported milk application, and whether those detections could precisely illustrate 17&amp;#946;-estradiol pre-ovulation peak in spite of its limited concentration and short manifestation in milk. Results: Milk sample treatments for progesterone and 17&amp;#946;-estradiol EIA...
Tipo: Journal article
Palavras-chave: Cattle; Estrous; Heat; Hormone; Insemination.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000400010

Identification of drought-responsive transcripts in peanut (Arachis hypogaea L.)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jain,Ashok K.; Basha,Sheikh Mehboob; Holbrook,C. Corley.
We have used a reverse transcriptase polymerase chain reaction procedure (differential display) to identify cDNAs corresponding to transcripts affected by water stress in peanuts (Arachis hypogaea L.). Using this method, we have identified several mRNA transcripts that are up- or down-regulated following water stress. With 21 primer combinations, a total of 1235 differential display products were observed in irrigated samples, compared to 950 differential display products in stressed samples. These products demonstrated qualitative and quantitative differences in the gene expression. The differentially expressed transcripts were collectively named PTRD (Peanut Transcripts Responsive to Drought). We have identified a total of 43 PTRD, which were...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200005

Biodegradation kinetics of o-cresol by Pseudomonas putida DSM 548 (pJP4) and o-cresol removal in a batch-recirculation bioreactor system
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kaymaz,Yasin; Babaoglu,Anil; Pazarlioglu,Nurdan Kasikara.
The biodegradation kinetics of o-cresol was examined by acclimatized P. putida DSM 548 (pJP4) in batch experiments at varying initial o-cresol concentrations (from 50 to 500 mg/L). The kinetic parameters of o-cresol aerobic biodegradation were estimated by using the Haldane substrate inhibition equation. The biodegradation kinetics of o-cresol was investigated. In batch culture reactors, the Maximum specific growth rate (&amp;#956;max), Monod constant (Ks) and the inhibition constant (Ki) were established as 0.519 h-1, 223.84 mg/L and 130.883 mg/L, respectively. o-cresol biodegradation in a batch-recirculation bioreactor system by immobilized P. putida was also studied. The recycled packed bed reactor system, which was composed of Ca-alginate beads and...
Tipo: Journal article
Palavras-chave: Biodegradation; Cell immobilization; O-cresol; Pseudomonas putida; Substrate inhibition kinetics.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000100003

Infectious pancreatic necrosis virus (IPNV) enumeration through epifluorescence microscopy: technical aspects
Provedor de dados: Electronic Journal of Biotechnology
Autores: Pavlov,Maria Soledad; Eissler,Yoanna; Espinoza,Juan Carlos; Garland,David E; Kuznar,Juan.
A method for counting Infectious pancreatic necrosis virus (IPNV) through epifluorescence microscopy was analyzed in detail. Image processing and statistic considerations are included. The particle size of viruses was compared in different experimental conditions such as the staining of the virus with SYBR-Green I or with antibodies for specific fluorescence labeling of viral proteins. The type of surface used as mounting support was assayed as well. The results indicated that the most suitable method involves the mounting of the viral-containing suspension on a membrane filter followed by the staining with a monoclonal antibody specific for a viral protein combined with a FITC (fluorescein isothiocyanate)-conjugated secondary antibody.
Tipo: Journal article
Palavras-chave: Digital image analysis; Fluorescence microscope methods; Immunofluorescence; Infectious pancreatic necrosis virus (IPNV); SYBR-Green I.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000100011

Managing agricultural biotechnology in Colombia
Provedor de dados: Electronic Journal of Biotechnology
Autores: Schuler,Ingrid; Orozco,Luis Antonio.
The international scenario for biotechnology shows a rapid tendency at industrialized countries in the increase of publications, patents, enterprises and novel solutions for the industry, the environment, health and agriculture. Nevertheless, Colombia has an important delay in relation to the international scientific development and the capacity to generate wealth and services for its productive systems. This delay has been one of the concerns of the country's policy during the last years, and more precisely since 2002, when for the first time biotechnology was included in a National Development Plan as one of the mechanisms for competitiveness and the use of biodiversity and genetic resources. This paper is the result of a survey conducted in 2005 aimed...
Tipo: Journal article
Palavras-chave: Agricultural biotechnology; Indicators; Legislation; Policies; Public perception.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300001

Production of natural and rare pentoses using microorganisms and their enzymes
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ahmed,Zakaria.
Biochemical methods, usually microbial or enzymatic, are suitable for the production of unnatural or rare monosaccharides. D-Arabitol was produced from D-glucose by fermentation with Candida famata R28. D-xylulose can also be produced from D-arabitol using Acetobacter aceti IFO 3281 and D-lyxose was produced enzymatically from D-xylulose using L-ribose isomerase (L-RI). Ribitol was oxidized to L-ribulose by microbial bioconversion with Acetobacter aceti IFO 3281; L-ribulose was epimerized to L-xylulose by the enzyme D-tagatose 3-epimerase and L-lyxose was produced by isomerization of L-RI. L-ribose and L-arabinose were prepared biochemically from ribitol by oxidation using Acetobacter aceti IFO 3281 and isomerization using L-RI and L-arabinose isomerase...
Tipo: Journal article
Ano: 2001
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200008

Funding of human stem cell research by the United States
Provedor de dados: Electronic Journal of Biotechnology
Autores: Jones,Phillip B.C.
During the fall of 1998, three research groups announced that they had devised methods for obtaining human embryonic stem cells. Human stem cells are characterized by the ability to form many cell types, and the scientific community anticipates that the cells should be useful for the treatment of a wide variety of diseases. The dilemma is that human stem cell methodology can require, at least to some extent, research with human fetal tissue or research involving human embryos. Those opposed to federal funding of the former are concerned that the studies would support the "legitimacy" of abortion, while the latter is seen as prohibited under current law. The National Bioethics Advisory Committee has suggested that the federal government should fund both...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000100003

Development of transformation vectors for the production of potentially high oleate transgenic oil palm
Provedor de dados: Electronic Journal of Biotechnology
Autores: Masani,Mat Yunus Abdul; Parveez,Ghulam Kadir Ahmad.
The main target of Malaysian Palm Oil Board (MPOB) genetic engineering programme is to produce high oleate transgenic palms. The availability of effective transformation vector is one of the pre-requisites for genetic manipulation of oil palm through recombinant DNA technology. Here, we describe the construction of a series of transformation vectors that have a maize ubiquitin promoter (UbiPro)-driven bar gene for selection of transformants on herbicide (Basta or Bialaphos), and mesocarp-specific promoter (MSP1) for expression of the transgenes [antisense palmitoyl-ACP-thioesterase (PAT) and sense &amp;#946;-ketoacyl-ACP-synthase II (KASII) and sense &amp;#916;9-stearoyl-ACP-desaturase (SAD)] potentially responsible for high oleate content in oil palm...
Tipo: Journal article
Palavras-chave: Oleate; Transformation vectors; Transgenic oil palm.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300003

Clonal diversity and antimicrobial resistance of Enterococcus faecalis isolated from endodontic infections
Provedor de dados: Electronic Journal of Biotechnology
Autores: Suliman Al-Badah,Abdulhakim; S.S. Ibrahim,Abdelnasser; Al-Salamah,Ali A; Ibrahim,Shebl Salah S.
Background Enterococcus faecalis is considered to be one of most prevalent species in the oral cavity, particularly in endodontic infections. The aim of the present study was to investigate the prevalence of E. faecalis in dental root canals, clonal diversity by restriction fragment length polymorphism (RFLP) and randomly amplified polymorphic DNA (RAPD-PCR) analysis, and the antibiotic susceptibility of E. faecalis isolates. Results Among the bacterial strains isolated from dental root canal specimens (n = 82), E. faecalis was determined to have the highest prevalence followed by Streptococcus viridians, Leuconostoc mesenteroides, Staphylococcus aureus, Streptococcus mitis, and Pediococcus pentosaceus. Cluster analysis of RAPD-PCR and RFLP patterns of the...
Tipo: Journal article
Palavras-chave: Antimicrobial susceptibility; Endodontic infection; Enterococcus faecalis; Genotype; RAPD; RFLP.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300006

Guava Psidium guajava seed flour and dry Aspergillus niger mycelium as nitrogen sources for the production of biomass and antimicrobial compounds produced by Weissella confusa
Provedor de dados: Electronic Journal of Biotechnology
Autores: Serna-Cock,Liliana; Mera-Ayala,José Daniel; Angulo-López,Jorge Eduardo.
Background: The fermentation substrate efficiency of glucose supplemented with guava seed flour (GGSF) or glucose supplemented with dry Aspergillus niger mycelium (GANM) was evaluated during the production of biomass and antimicrobial compounds by the lactic acid bacteria Weissella confusa. Results: The fermentation substrate efficiency was measured by comparing the biomass formation, substrate consumption, substrate conversion, antimicrobial activity and product yield. The antimicrobial activity was measured against a commercial Staphylococcus aureus strain. The results were compared against fermentations performed in a commercial substrate (CS), the MRS (Man-Rogosa-Sharpe) substrate. The fermentations were performed discontinuously for 4 hrs at 100 rpm...
Tipo: Journal article
Palavras-chave: Agroindustrial residue; Bacteriocin; Biomass; Inhibition.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600017

Application of bioleaching to copper mining in Chile
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gentina,Juan Carlos; Acevedo,Fernando.
Background: Bioleaching of minerals is a process that allows the treatment of insoluble sulphides and insoluble oxides via hydrometallurgy, as opposed to the more traditional technology of pyrometallurgy. Bioleaching presents several technological, environmental and economic advantages as compared with pyrometallurgy, as well as some limitations. Results: In this work a general panorama of copper mining and biomining, the influence of the most relevant operating variables and their present and future situation in Chile are presented and discussed. Conclusions: Today, Chile plays an important role in the development and commercial application of bioleaching to copper ores. This background information allows predicting a brilliant future for this technology...
Tipo: Journal article
Palavras-chave: Dumps; Heap leaching; Hydrometallurgy; Leaching microorganisms; Pyrometallurgy.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000300016

Influences of phenolic compounds on citric acid productivity by Aspergillus niger in stirred fermentor
Provedor de dados: Electronic Journal of Biotechnology
Autores: Çevrml,Bekir Stk; Karipta,Ergin; Yaar,Ahmet; Ytolu,Mustafa.
Influences of phenol, ?-naphtol and ?-naphtol, which are toxic chemicals, on citric acid biosynthesis and biomass in the artificial culture setting of Aspergillus niger using batch fermenter are examined in the most favorable fermentation conditions, and a model is proposed. Addition of certain concentrations of phenol, ?-naphtol and ?-naphtol to the culture increases the citric acid production. According to this model, maximum citric acid concentration is 48.3 g L-1 in a culture that does not contain any toxic chemicals, whereas the maximum concentrations obtained in cultures containing 25 mg L-1 phenol, 25 mg L-1 alpha-naphtol and 15 mg L-1 beta-naphtol are 62.5 g L-1, 78.1 g L-1 and 86.0 g L-1, respectively. Moreover, addition of toxic chemicals to the...
Tipo: Journal article
Palavras-chave: A. niger; Citric acid; Fermenter; Toxic chemicals (phenols).
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000600008

Diffusional restrictions in glyoxyl-agarose immobilized penicillin G acylase of different particle size and protein loading
Provedor de dados: Electronic Journal of Biotechnology
Autores: Illanes,Andrés; González,José Miguel; Gómez,José Manuel; Valencia,Pedro; Wilson,Lorena.
Particle size and enzyme protein loading are design parameters of enzyme immobilization affecting biocatalyst performance that can be varied within broad margins. Their effect on mass transfer limitations at different bulk penicillin G concentrations has been studied with glyoxyl agarose immobilized penicillin G acylase biocatalysts of average particle size of 5·10-5m and 10·10-4m at protein loadings from 15 to 130 mg/g gel. Internal diffusional restrictions were evaluated for such biocatalysts: Thiele modulus varied from 1.17 for the small particles at the lower protein load to 5.84 for the large particles at the higher protein load. Effectiveness factors at different bulk substrate concentrations were determined for all biocatalysts, values ranging from...
Tipo: Journal article
Palavras-chave: Diffusional restrictions; Enzyme kinetics; Immobilized enzyme; Penicillin G acylase; Penicillin hydrolysis.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000100002

Assessment of somaclonal variation in somatic embryo-derived plants of yacon [Smallanthus sonchifolius (Poepp. and Endl.) H. Robinson] using inter simple sequence repeat analysis and flow cytometry
Provedor de dados: Electronic Journal of Biotechnology
Autores: Viehmannova,Iva; Bortlova,Zuzana; Vitamvas,Jan; Cepkova,Petra Hlasna; Eliasova,Katerina; Svobodova,Eva; Travnickova,Martina.
Background Yacon (Smallanthus sonchifolius) is a root crop native to the Andean region. Low sexual reproductive capacity is a major constraint facing the genetic breeding of this crop. Biotechnological techniques offer alternative ways to widen genetic variability. We investigated somaclonal variation in regenerants of yacon derived from in vitro somatic embryogenesis using simple sequence repeat (ISSR) analysis and flow cytometry. Results Twenty tested ISSR primers provided a total of 7848 bands in 60 in vitro regenerants and control plant. The number of bands for each primer varied from 3 to 10, and an average of 6.95 bands was obtained per ISSR primer. Eight primers were polymorphic and generated 10 polymorphic bands with 7.19% mean polymorphism. ISSR...
Tipo: Journal article
Palavras-chave: DNA polymorphism; Molecular markers; Ploidy level; Proembryogenic callus.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000200008

Morphological and chemical diversity in the Type IV glandular trichomes of Solananeae (S. sisymbrifolium and N. glauca) as germplasm resources for agricultural and food uses
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cesio,Verónica; Dutra,Carmelo; Moyna,Patrick; Heinzen,Horacio.
Morphological variation in type IV trichomes in Ss and Ng was studied through SEM. The differences can be related to chemical differences in the excreted sugar esters. Ng trichomes exude two fractions, one of glucose tri-esters and the other one of sucrose tetra-esters, in a 3:7 ratio. The main acid found forming these esthers, is 3-methylvalerianic acid, in consonance to those secreted by other Solanaceae. Esters from Ss are novel structures, which can also be separated into three fractions, two of arabinoxylans, and the other one of arabinose, all glycosilated with &amp;beta;-hydroxipalmitic acid and sterified with the C12-C16 acids. All five fractions have antifungic activity at &amp;#956;g/cm² concentrations, both against common and mycotoxigenic...
Tipo: Journal article
Palavras-chave: Antifungic activity; Interespecies variability; Mycotoxins; Sugar esters.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300021

Characterization of extracellular cellulose-degrading enzymes from Bacillus thuringiensis strains
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lin,Ling; Kan,Xianzhao; Yan,Hao; Wang,Danni.
The gram-positive spore-forming bacteria, Bacillus thuringiensis (Bt) strains produced novel cellulases which could liberate glucose from soluble cellulose, carboxymethyl cellulose (CMC), and insoluble crystalline cellulose. The maximal cellulase activities were obtained after 60 hrs incubation at 28ºC in a LB broth medium with 1% CMC. Maximum CMCase activities were got at 40ºC and pH 4.0, respectively, and more than 50% of its maximal activity was retained at 40-60ºC for 1 hr, while approximately 40% of its maximal activity was also retained after incubating at 70ºC for 1 hr. Most metal ions and reagents such as Ca2+, Mg2+, Cd2+, Pb2+, Zn2+, Cu2+, EDTA, and SDS inhibited the enzyme activities, but K+ and Mn2+ activated the activities. The enzymes from...
Tipo: Journal article
Palavras-chave: Bacillus thuringiensis; Cellulase; Cellulose-degrading; Characterization.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000300002

Effect of temperature on the anaerobic digestion of palm oil mill effluent
Provedor de dados: Electronic Journal of Biotechnology
Autores: Choorit,Wanna; Wisarnwan,Pornpan.
Two continuous stirred tank reactors (CSTRs) each fed with palm oil mill effluent (POME), operated at 37ºC and 55ºC, respectively, were investigated for their performance under varies organic loading rates (OLRs). The 37ºC reactor operated successfully at a maximum OLR of 12.25 g[COD]/L/day and a hydraulic retention time (HRT) of 7 days. The 55ºC reactor operated successfully at the higher loading rate of 17.01 g[COD]/L/day and had a HRT of 5 days. The 37ºC reactor achieved a 71.10% reduction of chemical oxygen demand (COD), a biogas production rate of 3.73 L of gas/L[reactor]/day containing 71.04% methane, whereas the 55ºC reactor achieved a 70.32% reduction of COD, a biogas production rate of 4.66 L of gas/L[reactor]/day containing 69.53% methane. An OLR...
Tipo: Journal article
Palavras-chave: Hydraulic retention times; Mesophilic reactor; Methane; Organic loading rate; Temperature variations; Thermophilic reactor; Volatile fatty acids.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000300005

Characterization and evaluation of coconut aroma produced by Trichoderma viride EMCC-107 in solid state fermentation on sugarcane bagasse
Provedor de dados: Electronic Journal of Biotechnology
Autores: Fadel,Hoda Hanem Mohamed; Mahmoud,Manal Gomaa; Asker,Mohsen Mohamed Selim; Lotfy,Shereen Nazeh.
Background Sugarcane bagasse was shown to be an adequate substrate for the growth and aroma production by Trichoderma species. In the present work the ability of Trichoderma viride EMCC-107 to produce high yield of coconut aroma in solid state fermentation (SSF) by using sugarcane bagasse as solid substrate was evaluated. The produced aroma was characterized. Results Total carbohydrates comprised the highest content (43.9% w/w) compared with the other constituents in sugarcane bagasse. The sensory and gas chromatography-mass spectrometric (GC-MS) analysis revealed that the highest odor intensity and maximum yield of volatiles were perceived at the 5th d of induction period. The unsaturated lactone, 6-pentyl-&amp;#945;-pyrone (6-PP), was the major...
Tipo: Journal article
Palavras-chave: 6-Pentyl-&amp;#945; -pyrone Gas chromatography-mass spectrometry Industrial waste.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000100002

Transformation of Monascus purpureus to hygromycin B resistance with cosmid pMOcosX reduces fertility
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lakrod,Kamolnan; Chaisrisook,Chulee; Skinner,Daniel Z.
Albino strain KB20M1 of Monascus purpureus was genetically transformed to hygromycin B resistance with cosmid pMOcosX, using biolistic bombardment. Conidia and mycelial fragments were used as the recipient material and rupture disk strengths of 6.2 and 9.3 MPa each yielded a transformed isolate from five bombardments. Southern analysis suggested a single copy of the cosmid had integrated into each of the transformants. Both of the independent transformants formed cleistothecia but ascospore formation was greatly reduced or absent, suggesting the integration and expression of the genes carried on pMOcosX interfered with fertilization and/or ascospore formation in this homothallic fungus.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000200007

Evaluation of the uniformity and stability of T-DNA integration and gene expression in transgenic apple plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Flachowsky,Henryk; Riedel,Marko; Reim,Stefanie; Hanke,Magda-Viola.
The generation of transgenic apple plants relies on the molecular analysis of transgene integration and expression based on polymerase chain reaction (PCR) analysis, blotting techniques and enzymatic assays on vitro leaves of putative transgenic regenerates. In order to assess the uniformity and the stability of transfer DNA (T-DNA) integration and gene expression, we studied 26 transgenic apple lines carrying the attacin E gene from Hyalophora cecropia, the &amp;#946;-glucuronidase gene, and the nptII gene. Plants were evaluated using standard molecular techniques, such as PCR, Southern blot, reverse transcription PCR (RT-PCR) and Enzyme Linked Immunosorbent Assay (ELISA), and propagated in vitro on non-selective antibiotic-free media for four years to...
Tipo: Journal article
Palavras-chave: Agrobacterium tumefaciens; Apple; Chimeric tissue; Gene silencing; Malus domestica; T-DNA leakage.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100003

New biotechnological applications of coconuts
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bustamante,José O.
Coconut is a major crop of many poor nations. The present paper shows with inexpensive fluorescence microscopy of the enhanced green fluorescent protein (EGFP), that coconut water has the capability of synthesizing proteins from recombinant DNA vectors. After only 4 hrs of 100 pM application of the EGFP plasmid (pEGFP), a strong fluorescent signal was detected with an off-the-shelf, low-tech CCD webcam. Since natural coconut water is sterile, this heat-stable delivery system may be a good option for the dissemination of food supplements and pharmaceuticals in poor nations. As expensive substances could be expressed in coconut water, through bioreactor technology or micropropagation, the concepts presented here may prove invaluable to the economic and...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000100002

A practical approach to the understanding and teaching of RNA silencing in plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Bazzini,Ariel A; Mongelli,Vanesa C; Hopp,H. Esteban; del Vas,Mariana; Asurmendi,Sebastián.
Gene silencing, also called RNA interference (RNAi) is a specific mechanism of RNA degradation involved in gene regulation, development and defense in eukaryotic organisms. It became an important subject in the teaching programs of molecular biology, genetics and biotechnology courses in the last years. The aim of this work is to provide simple and inexpensive assays to understand and teach gene silencing using plants as model systems. The use of transient and permanent transgenic plants for expressing reporter genes, like those derived from jellyfish green fluorescent protein (gfp) encoding gene, provides a nice, colorful and conclusive image of gene silencing. Three experimental approaches to evidence RNA silencing are depicted. In the first approach...
Tipo: Journal article
Palavras-chave: Gene silencing; GFP; HC-Pro; PDS; Protocols; PTGS; Teaching; Transgenic; Transient expression; TRV; VIGS.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582007000200002

L (+) lactic acid fermentation and its product polymerization
Provedor de dados: Electronic Journal of Biotechnology
Autores: Narayanan,Niju; Roychoudhury,Pradip K.; Srivastava,Aradhana.
Lactic acid has been first introduced to us as early as 1780 as a sour component of milk. Ever since we have found its applications in food, pharmaceutical, cosmetic industries etc. Now there are emerging uses as a potential feedstock for the biodegradable polymer industry. The microorganisms being used for lactic acid fermentation, the raw materials reported, the various novel fermentation processes and its processing methods have been reviewed. The properties and applications of lactic acid, its derivatives and polymer have been discussed. The various routes to polymerization and the companies presently involved in lactic acid production have been covered
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200008

Visualization and Functional Analysis of a Maxi-K Channel (mSlo) Fused to Green Fluorescent Protein (GFP)
Provedor de dados: Electronic Journal of Biotechnology
We have constructed a fusion protein between mSlo (a recombinant, high conductance, calcium-activated potassium channel or maxi-K), and GFP (green fluorescent protein). This construct represents a tag to not only monitor channel expression, but to locate the protein in living cells. The GFP was fused in frame to the carboxy-terminus of the mSlo core protein (mSlo-GFP fusion protein). Expression of this fusion protein in COS-7 cells resulted in robust fluorescence localized near the cell membrane. Fluorescing cells that were patch clamped exhibited whole cell currents with a direction consistent with potassium currents. Conversely, non-fluorescing cells showed no significant whole cell currents. Excised inside out patches revealed single channel currents...
Tipo: Journal article
Ano: 1999
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34581999000300003

Expression of Bacillus thuringiensis insecticidal protein gene in transgenic oil palm
Provedor de dados: Electronic Journal of Biotechnology
Autores: Lee,Mei-Phing; Yeun,Li-Huey; Abdullah,Ruslan.
Oil palm, like all other crops, is susceptible to attack from several insect pests causing significant reduction in productivity. In the past, cry genes from Bacillus thuringiensis have been reported to be effective in conferring resistance towards insect pests in crops such as corn and rice. One of the advantages of these toxin proteins is their specificity towards certain harmful insects. A rapid and efficient method was developed for the transformation and evaluation of CryIA(b) expression in oil palm. A recombinant vector was introduced into immature embryos (IEs) of oil palm via the biolistic method. More than 700 putative transformed IEs from independent transformation events were generated. Transient transformation efficiency of 81-100 % was...
Tipo: Journal article
Palavras-chave: CryIA(b) gene; Gene expression; Insect resistance; Oil palm transformation; Rapid detection system; Transgenic oil palm.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200005

Biotransformation of (L)-citronellal to (L)-citronellol by free and immobilized Rhodotorula minuta
Provedor de dados: Electronic Journal of Biotechnology
Autores: Velankar,Harshad Ravindra; Heble,Mohan Ram.
This paper reports biotransformation of (L)-citronellal to (L)-citronellol using free and immobilized cells of Rhodotorula minuta. The culture preparation variables such as pH, temperature and incubation period for obtaining maximum cell growth of R. minuta were optimized. The optimized culture conditions for free and immobilized cells of R. minuta. have been compared for (L)-citronellal biotransformation. The various factors such as the optimum substrate concentration and the time of substrate addition at varying cell concentrations during the growth of yeast culture were also studied. Highest (L)-citronellol concentration of 3.5 gl-1 was obtained with free cell catalyzed biotransformation at pH 5.5, 27ºC and 150 rpm after 8 hrs using initial...
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000200004

Characterization of the nuclear ribosomal DNA unit in Oxalis tuberosa (Oxalidacea) and related species
Provedor de dados: Electronic Journal of Biotechnology
Autores: Tosto,Daniela; Hopp,Esteban.
Oxalis tuberosa is an octoploid Andean tuber crop called "oca" that belongs to the worldwide distributed genus Oxalis. The genus is very heterogeneous and its systematics is still problematic. It has been proposed that O. tuberosa evolved by polyploidization of a still not defined ancestor that belongs to an alliance of species sharing the same basic chromosome number (x = 8). Nuclear rDNA units of O. tuberosa and a selected group of four related diploid species were characterised by RFLP using different restriction endonucleases and southern hybridization probes to produce a restriction map for EcoRI and BamHI. The major rDNA unit length in O. tuberosa was estimated at 10.7 kbp. As expected, restriction site variation was observed mainly in the intergenic...
Tipo: Journal article
Palavras-chave: Andean crops; Oca; Oxalis; RDNA; RFLPs.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000300002

Effect of jasmonic acid and aluminium on production of tropane alkaloids in hairy root cultures of Brugmansia candida
Provedor de dados: Electronic Journal of Biotechnology
Autores: Spollansky,Tatiana C.; Pitta-Alvarez,Sandra I.; Giulietti,Ana M.
Hairy root cultures of Brugmansia candida (Solanaceae), a South American plant which produces scopolamine and hyoscyamine, were exposed to different elicitors (jasmonic acid (JA) and aluminum chloride (AlCl3)) in order to increase their productivity and/or stimulate their liberation. Hairy roots of 19-day old cultures (exponential phase) were exposed to these elicitors for 24 and 48 hours. The effects on alkaloid accumulation and release into the medium were evaluated. JA was tested at 2.5 and 25 m g/ml. After 24 hours, JA promoted the release of hyoscyamine (~1200%) when the highest concentration was used. Therefore, the positive effects seen with JA could possibly be attributed in part to ethanol (EtOH), the solvent in which the acid was dissolved. At...
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000100006

Molecular cloning, expression pattern, and putative cis-acting elements of a 4-coumarate:CoA ligase gene in bamboo (Neosinocalamus affinis)
Provedor de dados: Electronic Journal of Biotechnology
Autores: Cao,Ying; Hu,Shang-lian; Huang,Sheng-xiong; Ren,Peng; Lu,Xue-qin.
Background: 4-coumarate:CoA ligase (4CL) plays an important role at the divergence point from general phenylpropanoid metabolism to several branch pathways. Although 4CL sin higher plants have been extensively studied, little has known about the 4CL gene of bamboo. Results: In current study, a Na4CL gene putative encoding 4-coumarate:CoA ligase (4CL) and its 5&amp;#146;-flanking region were isolated from bamboo (Neosinocalamus affinis) by RACE-PCR and genomic DNA walker, respectively. Na4CL encodes a predicted protein of 557 amino acids, with conserved motifs of adenylate-forming enzymes. Phylogenetic analysis showed that Na4CL shared 62~85% identity with other known plant 4CLs, and cluster closely with some known 4CLs in monocots. Sequence analysis...
Tipo: Journal article
Palavras-chave: Expression pattern; Neosinocalamus affinis; Promoter; RACE; RNAi.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500009

Biotechnology in Mauritius: current status and constraints
Provedor de dados: Electronic Journal of Biotechnology
Autores: Puchooa,Daneshwar.
Agriculture today faces the challenge of sustainable productivity and improved food security on a shrinking area of land under cultivation. Until recently, biotechnology has been viewed as an expensive technology affordable only by rich industrial countries. However, it is now increasingly considered as an essential tool for developing countries to tackle the numerous problems of underdevelopment. Unfortunately, to date, Mauritius, like many other countries in Africa, lags far behind in development, use and commercialisation of biotechnology. This paper outlines the current status of biotechnology in Mauritius, some important constraints faced, as well as how policy makers are planning to make Mauritius &amp;ldquo;assume the role of a service provider and...
Tipo: Journal article
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200004

Construction of an engineered alpha 1-antitrypsin with inhibitory activity based on theoretical studies
Provedor de dados: Electronic Journal of Biotechnology
Autores: Sangachini,Elham Dasi; Hasannia,Sadegh; Taghdir,Majid; Pirooznia,Nazanin; Ghadicholaei,Kamran Khalili.
Background: The elastase inhibitor &amp;#945;-1-antitrypsin (AAT), is a member of the serpin superfamily of protease inhibitors. AAT has a characteristic secondary structure of three-&amp;#946;-sheets, nine-&amp;#945;-helices and a reactive central loop (RCL). This protein inhibits target proteases by forming a stable complex in which the cleaved RCL is inserted into &amp;#946;-sheet-A of the serpin, leading to a conformational change in the AAT protein. Spontaneous polymerization and instability of AAT are challenges with regard to producing drugs against AAT-deficient diseases. Therefore, the purpose of many investigations currently is to produce drugs with lower degrees of polymerization and higher stabilities. In order to investigate the effect of the...
Tipo: Journal article
Palavras-chave: Alpha1-antitrypsin; Molecular dynamic simulation; Pichia pastoris.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000200008

Purification and characterization of xylanases from Trichoderma inhamatum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Silva,L.A.O; Terrasan,César Rafael Fanchini; Carmona,Eleonora Cano.
Background Two xylanases, Xyl I and Xyl II, were purified from the crude extracellular extract of a Trichoderma inhamatum strain cultivated in liquid medium with oat spelts xylan. Results The molecular masses of the purified enzymes estimated by SDS-PAGE and gel filtration were, respectively, 19 and 14 kDa for Xyl I and 21 and 14.6 kDa for Xyl II. The enzymes are glycoproteins with optimum activity at 50°C in pH 5.0-5.5 for Xyl I and 5.5 for Xyl II. The xylanases were very stable at 40°C and in the pH ranges from 4.5-6.5 for Xyl I and 4.0-8.0 for Xyl II. The ion Hg2+ and the detergent SDS strongly reduced the activity while 1,4-dithiothreitol stimulated both enzymes. The xylanases showed specificity for xylan, Km and Vmax of 14.5, 1.6 mg·mL-1 and 2680.2...
Tipo: Journal article
Palavras-chave: Enzyme purification; Physico-chemical properties; Trichoderma inhamatum; Xylanases.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000400009

The changes of organelle ultrastructure and Ca2+ homeostasis in maize mesophyll cells during the process of drought-induced leaf senescence
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ma,Yuan-Yuan; Guo,Xiu-Lin; Liu,Bin-Hui; Liu,Zi-Hui; Shao,Hong-Bo.
The changes of cell ultra structure as well as Ca2+ homeostasis involved in the drought-induced maize leaf senescence was investigated. Meanwhile, many indicatives of leaf senescence including thiobarbituric acid reactive substance (MDA), electrolyte leakage (EL), and chlorophyll along with soluble proteins were also detected during the process. The Polyethylene glycol6000(PEG6000)-incubated detached leaves showed a slight increase in the MDA content and electrolyte leakage during the first 30 min of our detection, which was corresponded to an unobvious alteration of the cell ultrastructure. Other typical senescence parameters measured in whole leaf exhibited a moderate elevation as well. Thereafter, however, the EL and MDA rose to a large extent, which...
Tipo: Journal article
Palavras-chave: Ca2+ homeostasis; Drought; Leaf senescence; Maize; Organelle ultrastructure; Signal transduction.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000300004

Identification of QTLs for pod and kernel traits in cultivated peanut by bulked segregant analysis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Gomez Selvaraj,Michael; Narayana,Manivannan; Schubert,A. Michael; Ayers,Jamie L; Baring,Michael R; Burow,Mark D.
Bulked segregant analysis was used to identify simple sequence repeat (SSR) markers associated with pod and kernel traits in cultivated peanut, to permit rapid selection of superior quality genotypes in the breeding program. SSR markers linked to pod and kernel traits were identified in two DNA pools (high and low), which were established using selected F2:6 recombinant individuals resulting from a cultivated cross between a runner (Tamrun OL01) and a Spanish (BSS 56) peanut. To identify quantitative trait loci (QTLs) for pod and kernel-related traits, parents were screened initially with 112 SSR primer pairs. The survey revealed 8.9% polymorphism between parents. Of ten SSR primer pairs distinguishing the parents, five (PM375, PM36, PM45, pPGPseq8D9, and...
Tipo: Journal article
Palavras-chave: Maturity; Oil quantity; Quality; SSR markers.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000200003

Application of response surface methodology for glucosyltransferase production and conversion of sucrose into isomaltulose using free Erwinia sp. cells
Provedor de dados: Electronic Journal of Biotechnology
Autores: Yukio Kawaguti,Haroldo; Manrich,Eiric; Harumi Sato,Hélia.
Isomaltulose is a structural isomer of sucrose commercially used in food industries. Glucosyltransferase produced by Erwinia sp. D12 catalyses an intramolecular transglucosylation of sucrose giving isomaltulose. The Experimental design and response surface methodology were applied for the optimization of the nutrient concentration in the culture medium for the enzyme production in shaken flasks at 200 rpm and 30ºC. The three variables involved in this study were sugar cane molasses, bacteriological peptone and yeast extract Prodex Lac SD®. The statistical analysis of the results showed that, in the range studied, all the factors had a significant effect (p &lt; 0.05) on glucosyltransferase production and the highest enzyme activity was observed in culture...
Tipo: Journal article
Palavras-chave: Batch process; Erwinia sp.; Free cells; Glucosyltransferase; Isomaltulose; Response surface methodology.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500003

Molecular characterization of a novel thermostable laccase PPLCC2 from the brown rot fungus Postia placenta MAD-698-R
Provedor de dados: Electronic Journal of Biotechnology
Autores: An,Hongde; Xiao,Tingting; Fan,Huan; Wei,Dongsheng.
Background Laccase has been considered important for the degradation of lignocellulose by wood rot fungi. The properties and functions of laccase in white rot fungi have been investigated extensively, but those from brown rot fungi remain largely unknown. In this paper, a laccase isoform Pplcc2 from the brown rot fungus Postia placenta MAD-698-R was expressed heterologously in Pichia pastoris GS115, purified and the properties of the enzyme were determined. Results The molecular weight of the protein was determined to be 67 kDa using SDS-PAGE. It cannot oxidize syringaldazine (SGZ), but it can oxidize 2,2'-azino-di-(3-ethylbenzothialozin-6-Sulfonic acid) (ABTS) and 2,6-dimethoxyphenol (DMP). Specific activity for ABTS was 1960 ± 19 Unit/mg. The catalytic...
Tipo: Journal article
Palavras-chave: Brown rot fungi; Pichia pastoris; Postia placenta; Thermostable laccase.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000600011

Obtainment of embryogenic cell suspensions from scalps of the banana CIEN-BTA-03 (Musa sp., AAAA) and regeneration of the plants
Provedor de dados: Electronic Journal of Biotechnology
Autores: Ramírez-Villalobos,Maribel; de García,Eva.
The purposes of this work were to obtain embryogenic cell suspensions (ECS) from scalps and to regenerate plants of the banana CIEN-BTA-03. Shoot apexes were grown in the scalp-induction medium of Murashige and Skoog plus BA and IAA, following four diverse treatments. The first two, ME22 and ME25, were solid media supplemented with (mg L-1) 22.7 BA plus 0.192 IAA, and 25 BA plus 0.217 IAA, respectively, all containing 1.8 g L-1 of phytagel, and subcultures were performed monthly and bimonthly over 16 months. The other two treatments, IT22 and IT25, resembled ME22 and ME25 but consisted in temporary immersion for four months without subcultures, followed by two months in solid media. The scalps were grown in callus-induction medium and embryogenic calluses...
Tipo: Journal article
Palavras-chave: Bananas; Embryogenic callus; Embryogenic cell suspension; Musa sp; Plant regeneration; Scalp; Secondary somatic embryogenesis.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000500006

Use of volatile fatty acids salts in the production of xanthan gum
Provedor de dados: Electronic Journal of Biotechnology
Autores: Correa Leite,José Alberto; Pozzi,Eloiza; Pelizer,Lúcia Helena; Zaiat,Marcelo; Barboza,Marlei.
Background: The aim of this study was the production of xanthan gum from salts of volatile fatty acids, which can be generated in anaerobic processes for the production of hydrogen from organic wastewaters. Xanthan gum was produced with three different acid salts used to replace the traditional citrate, which is normally used in the culture for the production of this biopolymer. The volatile fatty acids (VFA) salts used were sodium acetate 0.0328 M, sodium propionate 0.0219 M, and sodium butyrate 0.0164 M. Results: The values of biomass yield, (Yp/x) obtained were 9.2 g/g for acetate, 11.78 g/g for citrate, 11.80 g/g for butyrate and 14.59 g/g for propionate, while the values of the product yield (Yp/s), were 0.92; 0.59; 0.71 and 0.72 for acetate, citrate,...
Tipo: Journal article
Palavras-chave: Rheology; Volatile fatty acids; Xanthan gum.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000200006

Antioxidant activity and protective role on protein glycation of synthetic aminocoumarins
Provedor de dados: Electronic Journal of Biotechnology
Autores: Aminjafari,Akram; Miroliaei,Mehran; Angelova,Violina T; Emamzadeh,Rahman; Djukic,Mirjana M; Djuric,Ana; Saso,Luciano.
Background: Synthesized aminocoumarins are heterocyclic compounds possessing potential for the treatment of insulin-dependent diabetes mellitus with unexplored anti-glycative action. Results: In this study 4-aminocoumarin derivatives (4-ACDs) were evaluated in vitro for antiglycation (AG) activities by using the human serum albumin (HSA)/glucose system, for 8 weeks of incubation. The glycation and conformational alteration of HSA in the presence of the tested compounds were evaluated by Congo red assay, fluorescence and circular dichroism spectroscopy. The antioxidant (AO) capacity were also tested by four different assays including: DPPH (2,2'-diphenyl-1-picrylhydrazyl radical), ABTS (2,2-azinobis (3-ethylbenzothiazoline-6-sulphonate) diammonium salt),...
Tipo: Journal article
Palavras-chave: Anti-glycation agents Diabetes; 4-Aminocoumarin derivatives Congo red Spectropolarimetry Spectrofluorimetry.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000600007

Discrimination of population of recombinant inbred lines of rye (Secale cereale L.) for different responses to nitrogen-potassium stress assessed at the seedling stage under in vitro conditions
Provedor de dados: Electronic Journal of Biotechnology
Autores: Smolik,Mi&amp;#322;osz.
Background: Plants differ in the methods used to acquire nutrients from environments with low nutrient availability, and may change the morphology of their ‘root architecture’ to be able to take up nutrients. Results: In the present study rye response to stress caused by high and low nitrogen-potassium treatments in mature embryos cultures was described within a population consisting of one hundred and thirty eight recombinant inbred lines of rye. Characterization of the response of recombinant inbred lines (RILs) to nutrient stress was presented as the results of analyses of morphological traits, and physiological and biochemical parameters of the seedlings grown in both treatments. A wide range of variability of individual RILs to induced stress was...
Tipo: Journal article
Palavras-chave: Mature embryos; Nutrient stress; Oxidative stress; RILs; Rye.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000100005

"Comics" as a tool for teaching biotechnology in primary schools
Provedor de dados: Electronic Journal of Biotechnology
Autores: Rota,Gladis; Izquierdo,Juan.
Tipo: Journal article
Ano: 2003
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582003000200003

Production of polyclonal antisera to manganese superoxide dismutase expressed in downy mildew resistant pearl millet and its application for immunodiagnosis
Provedor de dados: Electronic Journal of Biotechnology
Autores: Urs Babitha,Mysore Pandurangaraj; Madhu,Devaiah; Sripathi P,Harishchandra; Shekar Shetty,Hunthrike.
Level of superoxide dismutase (SOD) in the seedlings of downy mildew resistant pearl millet genotype (IP 18293) increased 3-fold upon inoculation with Sclerospora graminicola. Mn-SOD was purified from pearl millet by ion-exchange and gel filtration chromatography. Polyclonal antibody was raised in rabbit against Mn-SOD of pearl millet. Anti-Mn SOD had an antibody titer of 1:20,000. ELISA results revealed a 1.5-fold increase in pure Mn-SOD preparation compared to the crude preparation. The antibody reactivity as detected by ELISA revealed that Mn-SOD is higher at 4 hrs post-inoculation in resistant pearl millet seedlings. The reactivity also showed the Mn-SOD is more in roots of inoculated resistant seedlings. SOD reactivity was also determined by DIBA...
Tipo: Journal article
Palavras-chave: DIBA; Downy mildew; ELISA; Immunofluorescence; Manganese superoxide dismutase; Pearl millet; Sclerospora graminicola; Western blot.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200007

Optimal immobilization of &amp;#946;-glucosidase into chitosan beads using response surface methodology
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhou,Ying; Wang,Lufeng; Wu,Ting; Tang,Xixuan; Pan,Siyi.
Background: &amp;#946;-Glucosidase is known as an effective catalyst for the hydrolysis of various glycosides and immobilization is one of the most efficient strategies to improve its activity recovery and properties. Results: Crosslinking-adsorption-crosslinking method was employed to immobilize &amp;#946;-glucosidase into chitosan beads and response surface methodology (RSM) was used to optimize the immobilized conditions of the maximum activity recovery. Enzyme concentration and adsorption time were found to be significant influence factors, and the maximum activity recovery (50.75%) obtained from response surface methodology was in excellent agreement with experimental value (50.81%). Furthermore, various characteristics of immobilized...
Tipo: Journal article
Palavras-chave: &amp;#946; -glucosidase characters chitosan beads immobilization response surface methodology.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600006

Microbial succession in a fermenting of wild forest noni (Morinda coreia Ham) fruit plus molasses and its role in producing a liquid fertilizer
Provedor de dados: Electronic Journal of Biotechnology
Autores: Kantachote,Duangporn; Kowpong,Kanjana; Charernjiratrakul,Wilawan; Pengnoo,Ashara.
The numbers of lactic acid bacteria (LAB) and yeasts that were present during a wild forest noni (Morinda coreia Ham) fermentation, the changes in its physico-chemical properties and levels of plant nutrients were investigated. LAB increased rapidly during the first 7 days and were the dominant population until after day 21 when the LAB were declining and the yeasts began to dominate. Identification of the LAB and yeasts to species level showed that the dominant LAB throughout was Lactobacillus plantarum while Lactobacillus pentosus was found but only at day 21. Saccharomyces cerevisiae was the most dominant species of yeast throughout but was slowly replaced by Pichia membranifaciens and then Pichia anomala. Rhodotolura mucilaginosa, an aerobic yeast, was...
Tipo: Journal article
Palavras-chave: Lactobacillus plantarum; Morinda coreia Ham; Physicochemical property; Pichia spp.; Plant nutrients; Wild forest noni fermentation.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000300009