Endoglucanase production with the newly isolated Myceliophtora sp. i-1d3b in a packed bed solid state fermentor

This work is aimed to produce endoglucanase through solid state fermentation in a packed bed bioreactor with the use of the fungus Myceliophtora sp. I-1D3busing a mixture of wheat bran (WB) and sugar cane bagasse (SCB) as culture medium. Preliminary tests were performed in polypropylene plastic bags, controlling the variables temperature (40, 45, and 50ºC), initial moisture content (75, 80, and 85%, w.b.), and weight proportion SCB/WB (1:1, 7:3, and 9:1). The highest enzyme activities in plastic bags were obtained using the substrate proportion of 7:3, 50ºC temperature, and 80% initial moisture content (878 U/grams of dry solid). High activities of filter-paper cellulase and xylanase were also obtained in plastic bags and some results are reported. For the packed bed experiments, the temperature (45 and 50ºC) and the air flow rate (80, 100 and 120L/h) were the controlled variables. Activity of endoglucanase was similar to plastic bag tests. A longitudinal gradient of moisture content, was observed increasing from the bottom to the top of the reactor, even though the longitudinal enzyme activity profile was flat for almost the whole bed. Air flow rate did not affect enzyme activity, while experiments carried out at 50ºC showed higher enzyme activities. The maximum temperature peak observed was at about 6ºC above the process temperature.

Production of microbial alkaline cellulase and studies of their characteristics

Com o objetivo de obter celulases que melhorassem a eficiência de produtos detergentes, isolou-se, a partir de solos e compostagens, dois microorganismos, Bacillus sp B38-2 e Streptomyces sp S36-2, através de incubaçäo de amostras em meio de cultura enriquecido, contendo CMC e Na2CO3 com pH9.6. Verificou-se que eles secretavam uma carboximetil celulase (CMCase) alcalina constitutiva, extracelular, em quantidade. A atividade enzimática máxima foi observada entre 48h e 72h a 30oC para o Streptomyces e entre os pH 6.0 e 7.0 a 55oC para o Streptomyces e entre os pH 7.0 e 8.0 a 60oC para o Bacillus. As duas atividades CMCases brutas permaneceram termoestáveis a 45oC durante 1 h e ambas as atividades enzimáticas brutas, tanto do Bacillus como do Streptomyces, ficaram estáveis na faixa de pH 5.0 - 9.0. após tratamentos em várias soluçöes-tampäo de diferentes valores de pH a 30oC durante 24 h

The effect of sorbose on NAD(P)ase production by Aspergillus nidulans

NAD(P)ase activity was stimulated when 1% sorbose was present in the culture medium of A. nidulans, and this effect was partially reversed by 1% glucose. 2. The level of extracellular NAD(P)ase was more affected by sorbose in the culture medium than the intracellular enzyme and no morphological changes were obtained. 3. The sorbose effect on NAD(P)ase activity appears to be specific sinle two other exoenzymes tested (ß-glucosidase and alkaline protease) show normal secretion patterns. 4. These findings suggest that the sorbose effect on NAD(P)ase production may be the consequence of metabolic disorders not necessarily linked with the morphological changes induced by the ketohexose