Abstract: Preparation of β-glucosidase by solid-state fermentation and its application in enzymatic hydrolysis of cellulose were investigated. The maximal β-glucosidase activity was 225.43IU/g dry base (based on koji) when Aspergillus niger NL02 was employed using corn cob and wheat bran as carbon sources for 5 days cultivation. β-Glucosidase was purified to homogeneity by ammonium sulfate precipitation, anion-exchange chromatography and gel filtration chromatography. The recovery of enzyme acti-vity and specific activity were 69.34% and 133.88IU/mg, respectively. Corn stalk pretreated by dilute sulfuric acid was hydrolyzed by the dosages of 20FPIU/g (based on cellulose) Trichoderma reesei cellulase and 4IU/g(based on cellulose) β-glucosidase at the substrate concentration of 100g/L for 48h, the concentration of cellobiose and glucose in hydrolysate were 1.12 and 42.68g/L, respectively, the yield of enzymatic hydrolysis and the ratio of fermentable sugar were 62.85% and 97.44%, respectively.

Key words: Aspergillus niger, β-glucosidase, cellulose hydrolysis, cellobiose