SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Dall´Agnol,Monique; Martinez,Marina Baquerizo.

This work aimed the study of acquisition of iron from different compounds by EIEC strains. Seven serotypes were studied (O28ac.H-, O29:H-, O136:H-, O144:H-, O152:H-, O164:H- and O167:H7-), in a total of 31 strains. All serotypes were able to use distinct iron sources: hemin, hematin, hemoglobin, ovotransferin, lactoferrin, transferrin and ferritin.

Toxic metabolites from culture filtrate of Fusarium oxysporum and its effects on cucumber cells and plantlets

Palavras-chave: EIEC; Iron; Iron uptake.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000200012

Melo,Itamar Soares de; Piccinin,Everaldo.

Resistance of cucumber plantlets to culture filtrate of Fusarium oxysporum is correlated with resistance of single cells from callus. Single cells and plantlets of two cultivars of cucumber were incubated with culture filtrates. Rapid cell death occurred, as assessed by the stain fluorescein diacetate. More cell death ocurred in the cells of the cultivar Aodai than in to cells of the cultivar Caipira, which presented high level of resistance. Maximum toxic activity of culture filtrates was attained after 21-25 days of growth of the fungus.

Ribonuclease Production by Aspergillus species

Palavras-chave: Fusarium oxysporum; Single cells; Cucumber; Toxic metabolites.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000200003

Gomes,Eleni; Silva,Roberto da; Serzedello,Alcides.

Ribonuclease production by Aspergillus flavipes, A. sulphureus and A. fischeri in semi-synthetic medium, after 24-144 hours at 30ºC under shaking, was studied. After cultivation, the medium was separated from micelia by filtration and the resultant solution was used as enzymatic extract. The highest amount of biomass and RNase was obtained after 96 hours of cultivation. The enzymes produced by three species presented similar characteristics, with optimum temperature at 55ºC and two peaks of activity at pH 4.5 and 7.0. A. flavipes RNases were more sensitive to temperature: 50% of the initial activity was lost after 1 hour at 70ºC. After this heat treatment, RNase of A. sulphureus lost 30% of this activity and that of A. fischeri only 16%. The nucleotides...

Equine leukoencephalomalacia associated with ingestion of corn contaminated with fumonisin B1

Palavras-chave: Ribonucleases; Aspergillus; Nucleotides.

Ano: 1998

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000300008

Mallmann,Carlos A.; Santurio,Janio M.; Dilkin,Paulo.

This article describes clinical, etiologic and pathologic diagnosis of an outbreak of equine leukoencephalomalacia. Two samples of the corn consumed by the affected horses contained fumonisin B1 at levels of 46 and 53 µg/g and Fusarium moniliforme, a good in vitro mycotoxin producer.

MICROBIAL ACTIVITY OF DARK RED LATOSOL SAMPLES STORED AT DIFFERENT TEMPERATURES

Palavras-chave: Corn; Leukoencephalomalacia; Fumonisin; Fusarium moniliforme; Chromatography.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000300011

Vieira,Francisco Cleber Sousa; Nahas,Ely.

The enzymatic activity of soil samples stored at temperatures of 5 to -12oC and at room temperature for 0-32 weeks was determined. While alkaline phosphatase and dehydrogenase activity was decreased compared to control in samples stored at low temperatures, acid phosphatase activity showed no significant change.

Use of remazol blue dyed avicel for the determination of cellulolytic activity in basidiomycetes

Palavras-chave: Phosphatase; Dehydrogenase; Soil storage.

Ano: 1998

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000300002

Correia,Marcos José; Pereira Junior,José Antônio de Sousa; Santos,Jefferson Cunha dos; Cavalcanti,Maria Auxiliadora de Queiroz.

A modified method for direct determination of cellulolytic activity using Avicel colored with Remazol Brilliant Blue R (RBBR) in Agar test tubes is discussed. Refinements were introduced in a simple method for quantitation of cellulase activity, based on the release of dye from Avicel-RBBR medium by the enzymatic hydrolysis. Modifications in Avicel-dye preparation were enhanced and a spectrophotometer for direct OD measurement in agar test tubes used. The use of a spectrophotometer improved the precision of the collected data, since absorbance measurements could be done at the maximum wavelenght for RBBR (595 nm).

Production and action pattern of inulinase from Aspergillus Niger-245: hydrolysis of inulin from several sources

Palavras-chave: Avicel; Cellulase; Remazol Blue; Lentinus edodes; Pleurotus ostreatus.

Ano: 1998

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000400010

Cruz,Vinícius DArcadia; Belote,Juliana Gisele; Belline,Márcia Zilioli; Cruz,Rubens.

A strain of Aspergillus niger isolated from soil samples showed great capacity to produce extracellular inulinase. Although the enzyme has been synthesized in presence of monosaccharides, sucrose and sugar cane molasse, the productivity was significantly higher (p<0.05) when the microorganism was inoculated in media formulated with dahlia extract and pure inulin, as carbon sources. With regard to the nitrogen source, the best results were obtained with casein and other sources of proteic nitrogen, comparatively to the mineral nitrogen. However, statistic significance (p<0.01) only was found between the productivity obtained in the medium prepared with casein and ammonium sulphate. The optimum pH of the purified enzyme for inulin hydrolysis...

Molecular evolution in bacteria: cell division

Palavras-chave: Inulinase; Aspergillus niger; Fructose syrup; Inulin.

Ano: 1998

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000400013

Trevors,J.T..

Molecular evolution in bacteria is examined with an emphasis on the self-assembly of cells capable of primitive division and growth during early molecular evolution. Also, the possibility that some type of encapsulation structure preceeded biochemical pathways and the assembly of genetic material is examined. These aspects will be considered from an evolutionary perspective.

Bacteria and protozoa populations in groundwater in landfill area in São Carlos, SP

Palavras-chave: Cell division; Molecular evolution; Bacteria; Self-assembly.

Ano: 1998

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000400001

Fusconi,Roberta; Godinho,Mirna Januária Leal.

The microbial populations of groundwaters were analyzed in a region under the influence of a landfill (piezometer L12) in the town of São Carlos, São Paulo, Brazil, and in an area not influenced by the landfill (piezometer L5). Heterotrophic bacteria were counted by spread plate method and the number of protozoa was estimated by the most probable number method. There was a larger number of organisms in well L12, with a mean value of 15.76 x 104 CFU/ml for bacteria and 9.7 MPN/ml for protozoa, whereas the mean values for piezometer L5 were 2.88 x 104 CFU/ml for bacteria and 3.4 MPN/ml for protozoa. The greater abundance detected in piezometer L12 may be related to the influence of the leachate through the landfill on the microbial populations, also...

Genetic variability of HIV-1 isolates from Minas Gerais, Brazil

Palavras-chave: Bacteria; Protozoa; Groundwater; Landfill.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000300003

Proietti,Anna Bárbara de Freitas Carneiro; Barbosa,Edel Figueiredo; Silva,Janaína Guernica; Carvalho,Alex Fiorini de; Kroon,Erna Geessien; Ferreira,Paulo César Peregrino.

We report results of nucleotide sequencing and phylogenetic analysis of the env gene of 11 HIV-1 isolates, in Belo Horizonte, Brazil. Ten isolates belonged to HIV-1 subtype B and one was a probable B/F mosaic. This putative B/F recombinant is similar but not identical in its nucleotide sequence to other B/F mosaics described in Brazil.

Occurrence of aflatoxins in peanuts and peanut products consumed in the State of São Paulo/Brazil from 1995 to 1997

Palavras-chave: HIV-1; Genome; PCR; AIDS; Hemophiliacs.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000200010

Sabino,Myrna; Milanez,Thais Valéria; Lamardo,Leda Conceição Antonia; Inomata,Emiko Ikejiri; Zorzetto,Maria Ângela Pompeu; Navas,Sandra Aparecida; Stofer,Monica.

One hundred and thirty seven samples of peanuts and peanut containing foods were collected in markets in the State of São Paulo, Brazil, between January 1995 an December 1997. Most of the samples were collected by the Inspection Service of São Paulo Secretary of Health. The foods included raw peanuts, peanut candies ("paçoca" and "pé de moleque"), peanut butter, fried/roasted salted peanuts, "torrone", chocolate coated peanuts and salt-coated peanuts. The samples were analyzed for aflatoxins using a thin-layer chromatographic method. About 45% of the samples were positive for aflatoxins and 27% exceeded the limits of the Brazilian legislation (30.0 µg.kg-1 for aflatoxins B1+G1). The aflatoxins were confirmed by derivatization with trifluoroacetic acid. The...

Cinnabarin synthesis by Pycnoporus sanguineus strains and antimicrobial activity against bacteria from food products

Palavras-chave: Aflatoxins; Peanuts; Peanut products; Thin-layer chromatography.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000100016

Smânia,Elza de Fátima Albino; Smânia Júnior,Artur; Loguercio-Leite,Clarice.

Among three strains of Pycnoporus sanguineus, MIP 89007 produced more cinnabarin than MIP 95001 and MIP 95002. The antimicrobial activity of cinnabarin was tested against 11 species of bacteria isolated from food. Bacillus cereus and Leuconostoc plantarum were the most sensitive to cinnabarin, being inhibited by 0.0625 mg/ml. Klebsiella pneumoniae was the least sensitive (>4.0 mg/ml).

Characterization of selected strains of mucorales using fatty acid profiles

Palavras-chave: Pycnoporus sanguineus; Cinnabarin; Antimicrobial activity; Fungus; Bacteria.

Ano: 1998

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000400017

Silva,Manuela da; Manfio,Gilson Paulo; Canhos,Vanderlei Perez.

The fatty acid profiles of several fungi of the order Mucorales (Zygomycetes), including Backusella lamprospora (Lendner) Benny and R.K. Benj., Benjaminiella youngii P.M. Kirk, Circinella simplex van Tieghem, Cunninghamella blakesleeana Lendner, Mortierella ramanniana (Möller) Linnem., Mucor circinelloides f. janssenii (Lendner) Schipper, Mycotypha microspora Fenner, Rhizomucor miehei (Cooney and R. Emerson) Schipper and Rhizomucor pusillus (Lindt) Schipper, and of Volutella sp. Fr., from the class Ascomycetes, were qualitatively analysed by gas-liquid chromatography in order to determine the taxonomic value of these chemotaxonomic markers. The fatty acids present in all strains were palmitic (16:0), oleic (18:1), linoleic (18:2) and <FONT...

Bacteriocin-like activity of oral Fusobacterium nucleatum isolated from human and non-human primates

Palavras-chave: Taxonomy; Chemotaxonomic marker; Fatty acids; Mucorales.

Ano: 1998

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000400008

Gaetti-Jardim Júnior,Elerson; Avila-Campos,Mario Julio.

Fusobacterium nucleatum is indigenous of the human oral cavity and has been involved in different infectious processes. The production of bacteriocin-like substances may be important in regulation of bacterial microbiota in oral cavity. The ability to produce bacteriocin-like substances by 80 oral F. nucleatum isolates obtained from periodontal patients, healthy individuals and Cebus apella monkeys, was examinated. 17.5% of all tested isolates showed auto-antagonism and 78.8% iso- or hetero-antagonism. No isolate from monkey was capable to produce auto-inhibition. In this study, the antagonistic substances production was variable in all tested isolates. Most of the F. nucleatum showed antagonistic activity against tested reference strains. These data...

Frequency of Nonfermentative Gram-Negative Bacilli Isolated from Clinical Materials of Pacients at Universidade Federal do Ceará Hospital Complex - Brazil

Palavras-chave: Fusobacterium nucleatum; Bacteriocin-like substance; Oral bacteria.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000400009

Frota,Cristiane Cunha; Moreira,José Luciano Bezerra.

Among one thousand eight hundred and thirty-four Gram-negative bacilli, isolated at Universidade Federal do Ceará hospital complex - Brazil, from January 1995 to February 1996, 456 (24.8%) were Nonfermentative Gram-Negative Bacilli (NFGNB). This study reports their identification to the species level and their frequency as well. Thirteen genera and thirty species were identified and Pseudomonas aeruginosa was the most frequent species (69.95%), followed by Acinetobacter baumannii (5.48%) and by Acinetobacter lwoffii (3.95%). Among the identified P.aeruginosa strains, 94.1% produced pigment but 7.9% of them produced pigment only after being cultivated several times. The frequency of the most species was similar to that reported in the literature.

Low cost production and purification of polyclonal antibodies to staphylococcal enterotoxin A

Palavras-chave: Nonfermentative Gram-Negative Bacilli; Pseudomonas aeruginosa.

Ano: 1998

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000300006

Oliveira,Tereza Cristina R.M. de; Hirooka,Elisa Yoko.

An immunization scheme for production of antiserum to staphylococcal enterotoxin A (SEA) is proposed. The reference method of Robbins and Bergdoll was modified to reduce the number of doses and the amount of toxin used per animal. The best immunization scheme used injections in days 0, 8, 24, 59, 62 and 67. The amount of toxin at each injection was 5, 6, 20, 50, 100 and 200mg, respectively. The total amount of toxin was 381mg, which corresponded to a reduction of 107mg in the amount of toxin for each animal when compared to the reference method. The average antiserum titer using the Optimum Sensitivity Plate...

ANTIBIOTIC PRODUCTION BY STREPTOMYCES HYGROSCOPICUS D1.5: CULTURAL EFFECT

Palavras-chave: Staphylococcus aureus; Enterotoxins; Detection; Immunization.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000200006

Bhattacharyya,Barun K.; Pal,Sushil C.; Sen,Sukanta K..

In an attempt to screen out new potent antibiotic producers from soil, Streptomyces hygroscopicus D1.5 was isolated and was found antagonistic to both bacteria and fungi. It could utilise arginine as nitrogen source and glycerol as carbon source at 0.75 g/l and 11.5 g/l level, respectively for maximum antibiotic yield.

Microbial contamination of stored hydrocarbon fuels and its control

Palavras-chave: Antibiotics; Fermentation; Streptomyces.

Ano: 1998

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000300003

Gaylarde,Christine C.; Bento,Fátima M.; Kelley,Joan.

The major microbial problem in the petroleum refining industry is contamination of stored products, which can lead to loss of product quality, formation of sludge and deterioration of pipework and storage tanks, both in the refinery and at the end-user. Three major classes of fuel are discussed in this article - gasoline, aviation kerosene and diesel, corresponding to increasingly heavy petroleum fractions. The fuel that presents the most serious microbiological problems is diesel. The many microorganisms that have been isolated from hydrocarbon fuel systems are listed. The conditions required for microbial growth and the methods used to monitor and to control this activity are discussed. The effects of various fuel additives, including biocides, are...

Susceptibility of cell lines to avian viruses

Palavras-chave: Biocides; Biofilms; Hydrocarbon fuels; Microbial corrosion; Storage tanks.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000100001

Simoni,Isabela Cristina; Fernandes,Maria Judite Bittencourt; Custódio,Renata Marconi; Madeira,Alda Maria Backx Noronha; Arns,Clarice Weis.

The susceptibility of the five cell lines - IB-RS-2, RK-13, Vero, BHK-21, CER - to reovirus S1133 and infectious bursal disease virus (IBDV vaccine GBV-8 strain) was studied to better define satisfactory and sensitive cell culture systems. Cultures were compared for presence of CPE, virus titers and detection of viral RNA. CPE and viral RNA were detected in CER and BHK-21 cells after reovirus inoculation and in RK-13 cell line after IBDV inoculation and with high virus titers. Virus replication by production of low virus titers occurred in IB-RS-2 and Vero cells with reovirus and in BHK-21 cell line with IBDV.

MICROBIAL COUNTS OF DARK RED LATOSOL SAMPLES STORED AT DIFFERENT TEMPERATURES

Palavras-chave: Reovirus; Infectious bursal disease virus; Cell lines; Susceptibility.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000400015

Vieira,Francisco Cleber Sousa; Nahas,Ely.

The number of colony forming units (CFU) of different groups of bacteria and fungi in samples stored at temperatures of 5 to -12oC for 0-32 weeks was evaluated. The number of CFU obtained after the different periods of storage of red latossol soil was compared with the number of colonies obtained immediately after removal of soil samples (time zero). The number of total bacteria and actinomycetes in the samples remained practically unchanged throughout the storage period. The number of Gram-negative bacteria decreased by as much as 69% compared to control, while the number of Bacillus spp and of fungi increased 1.9 to 4.9 times starting from the 12th week in samples stored at 5oC. Except for the variations observed in fungal counts, the remaining groups of...