This study evaluated the production of cellulolytic enzymes by an Aspergillus fumigatus strain, isolated from sugar cane bagasse, according to its ability to grow on microcrystalline cellulose as the sole carbon source. The effect of the carbon source (brewer's spent grain, sugarcane bagasse, and wheat bran) and of the nitrogen source (corn steep liquor and sodium nitrate) on cellulase production was studied using submerged and solid state cultivations at 30 degrees C. The highest levels of endoglucanase (CMCase) corresponded to 365 U L(-1) and was obtained using sugarcane bagasse (1%) and corn steep liquor (1.2%) in submerged fermentation within 6 days of cultivation. This supernatant was used to run a sodium dodecyl sulfate polyacrylamide gel electrophoresis that showed six bands with endoglucanase activity. CMCase activity was higher at 65 degrees C and pH 2.0, indicating that this microorganism produces a thermophilic and acid endoglucanase. Solid state cultivation favored FPase production, that reached 47 U g(-1) of dry substrate (wheat bran and sugarcane bagasse) within 3 days.

In the present paper, endo-β-1,4-xylanase production by Aspergillus fumigatus was evaluated in solid-state fermentation using low-cost substrates such as sugarcane bagasse (SCB), brewer's spent grain (BSG), and wheat bran (WB). The partial characterization of the crude enzyme was also performed. In the experimental conditions, the highest levels of endo-β-1,4-xylanase production by A. fumigatus FBSPE-05 occurred within 8 days incubation when using SCB/liquid medium at 1:2 ratio (219.5 U g(-1)) and 4 days incubation when using WB/liquid medium at 1:1 ratio (215.6 U g(-1)). Crude enzyme from this last condition was used to enzyme characterization, showing best enzyme activity at 60 °C and pH 6.0, which suggests a thermophilic endoxylanase. The crude enzyme retained 73% of its activity after 1 h at 60 °C, and zymogram has shown three bands of endo-β-1,4-xylanase activity, with different molecular masses. A. fumigatus FBSPE-05 was able to grow and produce good levels of endo-β-1,4-xylanase using agro-industrial by-products, making this strain worthy for further investigation. To our knowledge, this is the first study reporting the use of SCB and/or BSG as sole substrates for endoxylanase production by solid-state fermentation using A. fumigatus.

-Several types of lignocellulosic raw materials including wheat straw, sisal bagasse and sugarcane bagasse have different contents of cellulosic components. In our studies, aimed at isolating cellulose-degrading actinobacteria from Brazilian soils, a promising strain was selected and identified as Streptomyces sp. SLBA-08. This strain was tested for cellulase production under submerged fermentation in a mineral medium using different carbon sources (sisal bagasse, sugarcane bagasse and straw), as well as ammonium sulphate in different concentrations as nitrogen source. The results showed that medium containing 2.4% (w/v) sisal bagasse and 0.3% (w/v) ammonium sulphate resulted in the highest production of carboxymethylcellulase (1.11 U mL -1 ), after 48 hours. The pH and temperature profile showed optimal activity at pH 6.0 and 50 °C. As for thermostability, carboxymethylcellulases were tolerant at 50 °C, retaining 70% of the maximal activity even after 2h of incubation. The results obtained indicate that Streptomyces sp. SLBA-08 was capable of producing CMCase using lignocellulosic residues, especially sisal bagasse.

Endoglucanase production under submerged fermentation was studied using sugarcane bagasse (SCB) and oat bran (OB) as carbon source and corn steep liquor (CSL) as nitrogen source, in different concentrations using factorial design. Streptomyces diastaticus PA-01, isolated from a soil cave in Brazil, was selected as cellulolytic strain. The results after experimental validation showed that a medium containing 2.4% (w/v) SCB and 1.3% (w/v) CSL led to the highest production, 1,180.3 U.L -1 of endoglucanase, after the 5 th -day. A good level of endoglucanase (1,039.3 U.L -1 ) was obtained after the 4 th -day when 2.0% (w/v) OB and 1.65% (w/v) CSL were used. The pH and temperature profiles showed thermoacidophilic endoglucanase activity, with 70% of maximum activity at 50ºC, after 4 hours of pre-incubation. This is the first report on endoglucanase production by S. diastaticus PA-01 in the presence of SCB and OB. The strong positive effects of some metal ions (Zn 2+ , Mn 2+ and Ba 2+ ) on endoglucanase activity when this strain was grown on OB is an interesting biochemical characteristic for future biotechnological applications.

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