Characterization of β-glucosidase from corn stover and its application in simultaneous saccharification and fermentation

Purification and characterization of β-glucosidase from corn stover was performed and the enzyme was tried in SSF to evaluate the suitability of plant glycosyl hydrolases in lignocellulose conversion. A β-glucosidase with Mw of 62.4 kDa was purified to homogeneity from post-harvest corn stover. The following physicochemical and kinetic parameters of the β-glucosidase were studied respectively: optimum temperature, thermal stability, optimum pH, pH stability, Km, Vmax, Vi, cellobiose inhibition, tryptic peptide mass spectrometry and effect of metal ions and other reagents on the activity. The β-glucosidase activity on salicin was optimal at pH 4.8 and 37 °C. The unique property of optimum temperature makes the β-glucosidase potentially useful in SSF. In SSF of steam explosion pretreated corn stover, the supplementation of the purified β-glucosidase was more effective than Aspergillus niger β-glucosidase.