Monday, April 30, 2012
Napoleon Ballroom C-D, 3rd fl (Sheraton New Orleans)
The hydrolytic action of cellulases and hemicellulases has a fundamental importance to obtain fermentable sugars from lignocellulosic biomass, involving action of many enzymes such as cellulases, xylanases, ligninases, pectinase and others. Related to the proposed research, it was isolated some fungal strains from Cerrado area of the Mata Grosso do Sul state, Brazil (19º43'32"S and 51º55'48"W ). The isolated strains were cultivated on solid state fermentation process using wheat bran as carbon source. The fermentation process was carried out at 30 °C for 72 hours with 10 ml of saline solution (0.20 % (NH4)2SO4; 0.20 % K2HPO4) maintaining a 70 % of humidity. The enzymatic activity was determined using the xylan (0.5 %), carboxymetylcellulose (1.0 %) and avicel (0.5 %). The reduced sugar released by reaction was quantified by DNS method. The fungi strains named P1-14, P2‑2 and P5-2 has shown the better xylanase activity 99 U ml-1, 76 U ml-1 and 87 U ml‑1, respectively. The better activity CMCase was observed for strain P5‑2 (1.8 U ml-1). For strain P1-14, the CMCase and avicelase activities were 1.3 U ml-1 and 0.14 U ml-1. These fungal strains have shown a good xylanase and CMCase activies and minor avicelase activity, indicating that these isolated fungi have a potential for application in biofuel, paper and cellulose industries.
Supported by CNPq and FAPESP