Desenvolvimento de técnicas e avaliações de antimicrobianos visando a produção de etanol carburante

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Insights into the Specificity of Thioredoxin Reductase-Thioredoxin Interactions. A Structural and Functional Investigation of the Yeast Thioredoxin System

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cryptococcus haglerorum, sp nov., an anamorphic basidiomycetous yeast isolated from nests of the leaf-cutting ant Atta sexdens

A yeast strain (CBS 8902) was isolated from the nest of a leaf-cutting ant and was shown to be related to Cryptococcus humicola. Sequencing of the D1/D2 region of the 26S ribosomal DNA and physiological characterization revealed a separate taxonomic position. A novel species named Cryptococcus haglerorum is proposed to accommodate strain CBS 8902 that assimilates n-hexadecane and several benzene compounds. Physiological characteristics distinguishing the novel species from some other members of the C. humicola complex are presented. The phylogenetic relationship of these strains to species of the genus Trichosporon Behrend is discussed.

Sympodiomyces attinorum sp nov., a yeast species associated with nests of the leaf-cutting ant Atta sexdens

Four strains of a novel yeast species were isolated from laboratory nests of the leaf-cutting ant Atta sexdens in Brazil. Three strains were found in older sponges and one was in a waste deposit in the ant nests. Sequencing of the D1/D2 region of the large-subunit rRNA gene showed that the novel species, named Sympodiomyces attinorum sp. nov., is phylogenetically related to Sympodiomyces parvus. Unlike Sympodiomyces parvus, Sympodiomyces attinorum can ferment glucose, assimilate methyl alpha-D-glucoside, salicin and citrate, and grow at 37 degreesC, thus enabling these two species to be distinguished. Differentiation from other related species is possible on the basis of other growth characteristics. The type strain of Sympodiomyces attinorum is UNESP-S156(T) (=CBS 9734(T)=NRRL Y-27639(T)).

Synonymy of the yeast genera Moniliella and Trichosporonoides and proposal of Moniliella fonsecae sp nov and five new species combinations

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Yeast extract and prebiotic in pre-initial phase diet for broiler chickens raised under different temperatures

Objetivou-se nesta pesquisa avaliar o desempenho, o rendimento de carcaça e a morfometria intestinal de frangos de corte criados em diferentes temperaturas e que receberam na fase pré-inicial ração contendo ou não extrato de leveduras e prebiótico. Foram utilizados 1.440 pintos machos de 1 dia de idade, criados em diferentes câmaras climáticas. As rações, acrescidas ou não de extrato de leveduras e prebiótico, foram oferecidas somente na fase pré-inicial (1 a 7 dias). A partir do oitavo dia, todas as aves receberam a mesma ração, reajustada de acordo com as recomendações usuais. Adotou-se o delineamento experimental inteiramente casualizado em arranjo fatorial 3 × 2 × 2, composto de três temperaturas de criação (calor, conforto e frio) e dois níveis de extrato de leveduras (com ou sem) e prebiótico (com ou sem). O desempenho das aves foi avaliado considerando o ganho de peso, o consumo de ração, a conversão alimentar e a viabilidade aos 42 dias de idade. Também foram avaliados o rendimento de carcaça e a morfometria intestinal. O calor ambiente prejudicou o desempenho e o rendimento de carcaça. A inclusão de prebiótico na ração pré-inicial aumentou o ganho de peso e melhorou a conversão alimentar das aves criadas no calor. A inclusão dos produtos na ração de frangos de corte criados em ambiente de calor e no frio tem efeito benéfico sobre as vilosidades das aves.

Evaluation of yeast cell wall on the performance of broiles fed diets with or without mycotoxins

This experiment aimed at evaluating the effects of the interactions between aflatoxin (500 or 250 ppb) and ochratoxin (500 or 250 ppb), and the possible benefits of adding yeast cell wall to prevent the effects of these mycotoxins in broiler chickens. Relative organ weight gain and live performance were evaluated at 21 and 42 days of age. Results indicated that at the levels of mycotoxins included in the experimental diets, ochratoxin reduced feed intake and body weight gain, and aflatoxin only affect feed intake of 21-day-old birds. No interaction was observed between aflatoxin and ochratoxin at the levels used in experimental study. Yeast cell wall did not significantly reduced the deleterious effects of ochratoxins. No significant differences were observed in relative organ weight gain. Yeast cell wall improved feed conversion ratio when birds were fed either contaminated or non-contaminated feeds.

Inflammatory responses of Nile tilapia Oreochromis niloticus to Streptococcus agalactiae: effects of vaccination and yeast diet supplement

This study evaluated the effects of dietary supplementation with 0.3% Saccharomyces cerevisiae yeast cell wall and of vaccination against Streptococcus agalactiae on the cellular component of acute inflammation induced in the coelomic cavity of Nile tilapia Oreochromis niloticus and on survival of the fish after challenge. A total of 84 tilapia of mean (+/- SD) weight 125.0 +/- 1.5 g were distributed among twelve 310 l fiberglass tanks according to a 2 x 2 x 3 factorial design in the following manner: with and without supplementation; 2 stimulations (oily solution without S. agalactiae vaccine and vaccination); 15 d later all fish were intracoelomically challenged with 10(8) CFU ml(-1) of a homologous strain of S. agalactiae, and evaluated after 6, 24 and 48 h, with 7 replicates. The fish received the non-supplemented or supplemented diet for a total of 77 d. The vaccination was performed on the 60th day, intracoelomically, as a single injection of 0.5 ml of the vaccine containing 10(8) CFU ml(-1). Fifteen days later, all the fish were challenged with S. agalactiae by means of an intracoelomic inoculation of 10(8) CFU ml(-1). No mortality was observed among the supplemented fish. The fish that were fed the non-supplemented diet and immunized with the bacterium presented a mortality rate of 28.5%. Among the non-supplemented and non-immunized fish, the mortality rate was 38.09%. Supplementation, in both vaccinated and non-vaccinated fish, induced larger accumulations of thrombocytes, lymphocytes and macrophages at the inflammatory focus. The results suggest that supplementation with 0.3% yeast cell wall, in both vaccinated and non-vaccinated fish, improved the inflammatory response of the fish and protected against the challenge. Vaccination increased the defense response, but the effect was stronger when associated with supplementation with S. cerevisiae.

Carbon, nitrogen and phosphorus mineralization in two soils amended with distillery yeast

The possibility of using yeast from alcohol distilleries as a source of nutrients in soil was investigated. The following treatments were used: no fertilization (control), 0.5% (w/w) yeast, 1% (w/w) yeast, and NPK. The decomposition of yeast was monitored for 90 days in two soils. The CO, production and the microbial biomass were increased by art average of 1- to 3-fold by yeast incorporation compared to control. Protease activity also was enhanced 3- to 8-fold in the soils supplemented with yeast compared to control. The phosphatase activities were higher than control only during the first days. While nitrate contents increased in all treatments compared to control, available P only increased in the soils amended with 1%, yeast or NPK by 45-119% and 309-489%, respectively. These results indicate that there exists an excellent potential for the use of yeast in the soil as a source of nitrate and available P for plant nutrition. (C) 2003 Elsevier Ltd. All rights reserved.

Effects of dry sugar cane yeast on the diet intake, digestibility and bovine rumen microbial populations

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Humoral immune response of broilers fed diets containing yeast extract and prebiotics in the prestarter phase and raised at different temperatures

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Dried yeast (Saccharomyces cerevisae) as a protein source for horses

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Yeasts isolated from a fungus-growing ant nest, including the description of Trichosporon chiarellii sp nov., an anamorphic basidiomycetous yeast

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evidence for conformational changes in the yeast deoxyhypusine hydroxylase Lia1 upon iron displacement from its active site

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)