Cellulase production by recombinant Trichoderma reesei and its application in enzymatic hydrolysis of agricultural residues

Fed-batch fermentation was employed to improve the productivity of Trichoderma reesei cellulase. The optimal conditions were fed-batch initiating time 48 h, lactose concentration 15% and ratio of carbon to nitrogen 7. Fed-batch fermentation produced 2.11 times higher cellobiohydrolase activity than batch fermentation. The cellulase from T. reesei transformant C10 with enhanced cellobiohydrolase activity was applied to the enzymatic hydrolysis of the alkaline pretreated corn stover and rice straw. In comparison with the cellulase from T. reesei ZU-02, C10 cellulase showed better yields in the enzymatic hydrolysis of both corn stover and rice straw. A high yield of 93.8% was obtained when 20 FPIU/g dry substrate C10 cellulase, 10 IU/g dry substrate cellobiase and 300 U/g dry substrate xylanase were used in the enzymatic hydrolysis of alkaline pretreated corn stover.