关键词: β-葡萄糖苷酶, 木糖渣, 黑曲霉, 中心组合优化, 里氏木霉, 酶系复配

Abstract: Corncob residues are one kind of lignocellulosic material which having abundant of cellulose content and can be used as inducing carbon source to produce cellulose degradation enzyme. This article reported optimization process using Aspergillus niger to produce β-D-glucosidase. Firstly, a Plackett-Burman design was used to select the main factors which had obvious significance on the production of β-D-glucosidase from six factors. The results suggested that wheat bran,ammonium sulfate and sodium nitrate had significant effect on the production of β-D-glucosidase. On the basis of selection, a central composite design (CCD) was employed to optimize the process. It was suggested that the most optimization concentration of wheat bran, ammonium sulfate and sodium nitrate was 26.7g/L, 10.0g/L and 10.0g/L, respectively. Under the optimization condition the β-D-glucosidase activity was at 15.0IU/mL. Analysis of variance (ANOVA) was used for graphical analyses of the data to obtain the interaction between the process variables and the responses. The R² coefficient 92.12% and the p value 0 indicated a satisfactory adjustment of the quadratic model to the experimental data. The crude enzyme which prepared under the optimization condition was used to hydrolyze Corncob residues. The results suggested that when the crude enzyme prepared by Trichoderma reesei B4 and Aspergillus niger JH-1 were blended at the ratio of 1:1 enzymatic hydrolysis efficiency of the mixed crude enzyme was 4 times of the crude enzyme prepared by Trichoderma reesei B4.

Key words: β-D-glucosidase, corncob residues, Aspergillus niger, central composite design(CCD), Trichoderma reesei, enzyme cocktail