Production of Cellulase for Ethanol Fermentation from Pretreated Wheat Straw

Abstract

Effect of different media compositions on cellulase production was observed using a strain of Trichoderma viride. Medium with yeast extract as nitrogen source was found the best from the other sources used. Then two modes of fermentation solid state and submerged were compared for the enhanced cellulase production. Better cellulase activity was observed in submerged fermentation than the solid state fermentation. Effect of mash size and agitation was also studied. Small mash size with agitation showed higher cellulase activity than the large size pretreated wheat straw. Bacillus cellulosilyticus was also used for the cellulase production. Trichoderma produced enhanced activities of cellulase enzyme (20.738 ± 0.006 IU). Scarification of pretreated wheat straw released maximum sugar up to 16.1 g/L, after hydrolysis in 48 h using indigenously produced enzyme. The optimum conditions for the saccharification of pretreated wheat straw were 5 and 30 °C for pH and temperature, respectively in 48 h. The yield of ethanol was observed 10.4 g/L in saccharified wheat straw based medium.