Orientador: Eleonora Cano Carmona / Banca: Marta Cristina Teixeira Duarte / Banca: Luis Henrique Souza Guimarães / Resumo: Especies de Penicillium estao entre os fungos mais comumente encontrados na natureza. Sao eximios degradadores de materia organica apresentando, assim, papel fundamental nos habitat que ocupam. Neste trabalho, uma linhagem de Penicillium janczewskii, isolada do solo da Mata Atlantica, foi avaliada quanto a producao de xilanases e ß-xilosidases, enzimas responsaveis pela degradacao da xilana presente na materia vegetal. Alem disso, o outro objetivo desse trabalho foi caracterizar ambas as atividades no filtrado de cultura. A xilana de aveia mostrou-se a melhor fonte de carbono para inducao dessas enzimas seguida do farelo de trigo. A producao enzimatica tambem foi induzida, em niveis inferiores, por outros substratos lignocelulosicos. Ressalta-se ainda que nao houve producao de celulases, exceto em meios com farelo de trigo, farelo de aveia e lactose, nos quais baixos niveis foram produzidos. O estudo cinetico das atividades enzimaticas indicou niveis mais elevados de xilanase em culturas de 7 dias de idade, e de ß-xilosidases em culturas de 8 dias. A linhagem se desenvolveu bem na faixa de pH entre 3,0 e 9,0 em temperaturas entre 20 e 35 °C, sendo selecionados o pH 6,5 e 30 °C e o pH 5,0 e 25 °C como condicoes para producao das maiores atividades xilanasica e ß-xilosidasica, respectivamente. As condicoes otimas de atividade xilanasica foram pH 5,0 e 50 °C, e para a ß-xilosidase foram pH 4,0 e 75 °C, temperatura bastante elevada considerando o carater mesofilico desse microrganismo. A atividade xilanasica apresentou-se mais estavel em pHs de 6,0 a 9,5, enquanto a atividade ß-xilosidasica apresentou-se mais estavel em pHs acidos, de 1,6 a 5,5, faixa na qual manteve praticamente 100 % da atividade. As meias-vidas da atividade xilanase a 40, 50 e 60 °C foram de 183, 15 e 2,8 min, respectivamente. A atividade ß-xilosidasica apresentou... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Species of Penicillium are among the most common fungi found in the nature. They are excellent organic matter degraders, playing an important role in the habitat they live. In this work, a Penicillium janczewskii strain, isolated from soil of Atlantic Forest, was valuated for the production of xylanase and ß-xylosidase, enzymes responsible for degradation of xylan present in the vegetal material. Moreover, another aim of this work was to characterize both activities in the culture filtrate. Oat spelts xylan was the best inducer carbon source to these enzymes, followed by wheat bran. The enzymatic production was also induced, in inferior levels, for others lignocellulosic substrates. It was observed that the strain did not produce celulases, except when cultivated in medium with wheat bran, oat bran and lactose, in which low levels were produced. The kinetic study of the enzymatic activities indicated higher levels of xylanase in 7 days-old cultures and higher levels of ß-xylosidase in 8 daysold cultures. The strain developed well in pH between 3.0 and 9.0 and in temperature between 20 and 35 °C. It was selected pH 6.5 and 30 °C, and pH 5.0 and 25 °C as the conditions for highest production of xylanase and ß-xylosidase activities, respectively. The optima conditions for xylanase activity were pH 5.0 and 50 °C, and for ß-xylosidase activity were the pH 4.0 and 75 °C, an elevated temperature considering the mesophilic character of this microorganism. The xylanase activity was more stable in pH from 6.0 to 9.5, while the ß-xylosidase activity was more stable in acid pH, between 1.6 and 5.5, maintaining practically 100 % of the activity in this range. The half-lives of the xylanase activity at 40, 50 and 60 °C was 183, 15 and 2.8 min, respectively. The ß-xylosidase activity presented T50 of 144, 7.6 and 4.2 min at 50, 65 and 75 °C, respectively... (Complete abstract click electronic access below) / Mestre

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Plant biomass serves as a carbon and energy source for Streptomyces spp. which secrete degradative enzymes capable of breaking down the complex plant biomass into simple saccharides. Hemicellulose is a major component of plants and is composed of five and six carbon sugars, such as xylose and glucose. Enzymatic degradation of hemicellulose to obtain desired sugars has been a cornerstone of many industries, as well as the subject of worldwide research for additional sources of efficient enzymes for substrate conversion. In this study, environmentally-derived Streptomyces isolates were screened for their ability to hydrolyze oat-spelt and birchwood xylan in agar-based high throughput activity screens. Of the isolates tested, eight displayed high levels of substrate-degrading activity and were chosen for further characterization which included 16S rRNA gene analysis, microscopic analysis from both liquid and agar grown cultures, xylanase-specific activity, lignin peroxidase production and indole acetic acid production.Qualitative assessment of extracellular lactone signalling for all eight isolates was also performed. Putative lactone signalling was observed for Streptomyces isolates JLS1-C4, JLS1-A6, JLS2-D6 and KT1-B1 which exhibited xylanase-specific activities of 0.622 μmol/min/mg, 0.0243 μmol/min/mg, 0.721 μmol/min/mg, and 0.706 μmol/min/mg respectively. Streptomyces isolates JLS1-F12 and JLS1-C12 did not exhibit lactone signalling but did exhibit xylanase-specific activities of 0.125 μmol/min/mg and 0.0688 μmol/min/mg respectively. No xylanase-specific activity was detected for isolates JLS2- C7 and KT1-B8; however lactone signalling was observed for isolate KT1-B8. Streptomyces isolate JLS1-A6 degraded birchwood xylan optimally at pH 4 and 28°C with a maximal xylanase activity of 1.56 x10-3 μmol/min/mg. / UOIT

Lignocellulose is composed of lignin, hemicellulose, and cellulose. Lignocellulose waste is a sustainable and renewable resource available for use in biotechnological applications. Efficient enzyme production and enzymes with high catalytic activity are needed for the use of lignocellulose. The study of cellulases and xylanases that degrade cellulose and xylan into constituent monosaccharides is required to advance industrial application of these enzymes. The use of a traditional pure culture approach to discover and characterize cellulases and xylanases from novel actinomycete isolates and the use of metagenomics to uncover previously unidentified cellulase genes was undertaken. Actinomycetes were cultivated from soil samples and the isolate with the best cellulase and xylanase activity was subjected to strain improvement through protoplast fusion. Enhanced enzymatic activity was found in one fusant. Differential release of sugars from xylan was observed through gas chromatographic analysis between the parental and fusant cultures. Genome shuffling was observed in 16S rRNA genes after protoplast fusion. Finally, one putative endo-β-1,4-glucanase was discovered in a metagenomic library created from cellulose-enriched potting soil. / UOIT

Three thermophilic aerobic bacterial strain, Geobacillus thermoleovorans T4, Bacillus subtilis b5 and Bacillus licheniformis b6 were isolated from the wastewater of a Taiwan Sugar Company sugar refinery in Kaohsiung. All strains were capable of growth in cellulose containing medium. We found out that G. thermoleovorans T4 possessed both of the activity of cellulses and xylanase. This was the first report ever in this bacterial spices. Its endoglucanase was active at temperatures ranging from 30¢J to 100¢J, and pH ranging from 4.0 and 8.0. Its £]-glucosidase activities could be measured at 40¢J - 90¢J and pH 5.0 - 9.0. Its xylanase was active from 30¢J to 90¢J and pH from 3.0 to 10.0, while the exoglucanase was active at temperatures from 30¢J to 90¢J. The pH values of xylasnase was better than G. thermoleovorans K-3d. This enzyme was worth of possible in industry application. Both of B. subtilis b5 and B. licheniformis b6 contained a thermoactive endoglucanase. The endoglucanase of B. subtilis b5 was active at pH values between 4.0 and 7.5, and was thermostable at 100¢J for at least 1 hour ( retaining 60% of the original activity ). The stability of this enzyme was better than all known enzymes extracted from Bacillus spices. The endoglucanase of B. licheniformis b6 was active at pH values between 4.0 and 9.0, and thermostable at 60¢J for least 1 hour.

Made available in DSpace on 2014-06-11T19:27:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-07-18Bitstream added on 2014-06-13T19:14:50Z : No. of bitstreams: 1 terrasan_crf_me_rcla.pdf: 391328 bytes, checksum: cd22c1774316d416bfb6f9f645077ac6 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Especies de Penicillium estao entre os fungos mais comumente encontrados na natureza. Sao eximios degradadores de materia organica apresentando, assim, papel fundamental nos habitat que ocupam. Neste trabalho, uma linhagem de Penicillium janczewskii, isolada do solo da Mata Atlantica, foi avaliada quanto a producao de xilanases e ß-xilosidases, enzimas responsaveis pela degradacao da xilana presente na materia vegetal. Alem disso, o outro objetivo desse trabalho foi caracterizar ambas as atividades no filtrado de cultura. A xilana de aveia mostrou-se a melhor fonte de carbono para inducao dessas enzimas seguida do farelo de trigo. A producao enzimatica tambem foi induzida, em niveis inferiores, por outros substratos lignocelulosicos. Ressalta-se ainda que nao houve producao de celulases, exceto em meios com farelo de trigo, farelo de aveia e lactose, nos quais baixos niveis foram produzidos. O estudo cinetico das atividades enzimaticas indicou niveis mais elevados de xilanase em culturas de 7 dias de idade, e de ß-xilosidases em culturas de 8 dias. A linhagem se desenvolveu bem na faixa de pH entre 3,0 e 9,0 em temperaturas entre 20 e 35 °C, sendo selecionados o pH 6,5 e 30 °C e o pH 5,0 e 25 °C como condicoes para producao das maiores atividades xilanasica e ß-xilosidasica, respectivamente. As condicoes otimas de atividade xilanasica foram pH 5,0 e 50 °C, e para a ß-xilosidase foram pH 4,0 e 75 °C, temperatura bastante elevada considerando o carater mesofilico desse microrganismo. A atividade xilanasica apresentou-se mais estavel em pHs de 6,0 a 9,5, enquanto a atividade ß-xilosidasica apresentou-se mais estavel em pHs acidos, de 1,6 a 5,5, faixa na qual manteve praticamente 100 % da atividade. As meias-vidas da atividade xilanase a 40, 50 e 60 °C foram de 183, 15 e 2,8 min, respectivamente. A atividade ß-xilosidasica apresentou... / Species of Penicillium are among the most common fungi found in the nature. They are excellent organic matter degraders, playing an important role in the habitat they live. In this work, a Penicillium janczewskii strain, isolated from soil of Atlantic Forest, was valuated for the production of xylanase and ß-xylosidase, enzymes responsible for degradation of xylan present in the vegetal material. Moreover, another aim of this work was to characterize both activities in the culture filtrate. Oat spelts xylan was the best inducer carbon source to these enzymes, followed by wheat bran. The enzymatic production was also induced, in inferior levels, for others lignocellulosic substrates. It was observed that the strain did not produce celulases, except when cultivated in medium with wheat bran, oat bran and lactose, in which low levels were produced. The kinetic study of the enzymatic activities indicated higher levels of xylanase in 7 days-old cultures and higher levels of ß-xylosidase in 8 daysold cultures. The strain developed well in pH between 3.0 and 9.0 and in temperature between 20 and 35 °C. It was selected pH 6.5 and 30 °C, and pH 5.0 and 25 °C as the conditions for highest production of xylanase and ß-xylosidase activities, respectively. The optima conditions for xylanase activity were pH 5.0 and 50 °C, and for ß-xylosidase activity were the pH 4.0 and 75 °C, an elevated temperature considering the mesophilic character of this microorganism. The xylanase activity was more stable in pH from 6.0 to 9.5, while the ß-xylosidase activity was more stable in acid pH, between 1.6 and 5.5, maintaining practically 100 % of the activity in this range. The half-lives of the xylanase activity at 40, 50 and 60 °C was 183, 15 and 2.8 min, respectively. The ß-xylosidase activity presented T50 of 144, 7.6 and 4.2 min at 50, 65 and 75 °C, respectively... (Complete abstract click electronic access below)

A series of experiments were conducted to evaluate the effects of dietary enzyme supplementation in broilers exposed to a live coccidia oocyst vaccine. In each experiment, Cobb 500 broilers were obtained at day of hatch from a commercial hatchery. Half of the chicks were sprayed with Coccivac BTM and housed in battery brooders in experiment (EXP) 1 and 2 or floor pens (EXP 3). Experimental diets were formulated according to Cobb 500 nutrient recommendations (positive control; PC) with the exception of Ca and available P (aP), which were reduced in the negative control (NC) diets approximately 0.1% (EXP 1), 0.11 and 0.13%, respectively (EXP 2), and 0.13% (EXP 3). Negative control diets in EXP 1 were supplemented with phytase (PHY), protease (PRO), xylanase (XYL), and the combination of PHY+PRO, PHY+XYL, and PHY+PRO+XYL. Negative control diets in EXP 2 were supplemented with PHY A, PHY B, and PHY C. In EXP 3, PC diets were supplemented with PHY at 1000 FTU/kg, and NC diets were supplemented with PHY at 1000 or 5000 FTU/kg. In all three experiments PHY supplementation generally improved (P ≤ 0.05) broiler performance and bone ash. Vaccination reduced (P ≤ 0.05) broiler performance in EXP 1 and 3, but increased (P ≤ 0.05) broiler performance in EXP 2. Xylanase and/or PHY supplementation tended to improve (P = 0.10) ileal amino acid digestibility (IAAD) in vaccinated broilers in EXP 1 and EXP 3. Phytase supplementation improved (P ≤ 0.05) IAAD and vaccination reduced (P ≤ 0.05) IAAD in EXP 3. Small intestinal morphology and goblet cell numbers were affected by enzyme supplementation and vaccination, which resulted in significant (P ≤ 0.05) interactions. In general, vaccination increased (P ≤ 0.05) small intestinal crypt depth and reduced (P ≤ 0.05) goblet cell numbers in EXP 3. Phytase supplementation of the NC diets fed to vaccinated broilers ameliorated the reduction in ileal goblet cells associated with vaccination (EXP 3). Enzyme supplementation tended to improve nutrient digestibility and altered small intestinal morphology in vaccinated broilers. Vaccination reduced broiler performance but nutrient digestion and dietary enzymes may improve nutrient utilization during a coccidia vaccination. / Ph. D.