Optimization of Solid-state Fermentation Conditions for β-glucosidase Production by Aspergillus fumigatus

-glucosidase is a key enzyme for the hydrolysis of lignocellulose into glucose.It plays a key role in cellulose hydrolysis and lignocellulosic ethanol production.This study aims at improving the production of -glucosidase by solid-state fermentation of Aspergillus fumigatus A27.Based on single factor and response surface optimizations, the optimal conditions were as follows: ratio of straw powder to bran, 5:0; nitrogen source, peptone; nitrogen content, 0.9%; ratio of material to water, 1:2; culture temperature, 36.4C;culture time, 6 d; initial medium pH, 3.16; and inoculum size, 10%.The activity of -glucosidase achieved under the optimal conditions was 63.950 IU/g, which was 2.3 times higher than that obtained under non-optimal conditions.