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| Registros recuperados: 7.826 | |
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| 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 |
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| 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 |
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| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582000000100005 |
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| 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 |
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| 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 (ΔG0, ΔH0 and ΔS0) 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 |
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| 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 |
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| 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 |
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| 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 |
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| Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582004000200013 |
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| 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 (> 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 |
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| 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 |
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| 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 |
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| 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 |
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| Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000300007 |
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| 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 |
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| Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582001000200009 |
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| 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 |
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| 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 |
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| 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 |
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| Registros recuperados: 7.826 | |
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