Efficient resveratrol production by immobilized β-glucosidase on cross-linked chitosan microsphere modified by l-lysine

Resveratrol and its glycosidic derivative polydatin are the major stilbenes in Polygonum cuspidatum, a most widely used traditional herbal medicine. To produce resveratrol via enzymatic hydrolysis of polydatin, β-glucosidase was immobilized on cross-linked chitosan microspheres modified by l-lysine. The condition of enzyme immobilization was optimized, and the characterization of the immobilized enzyme was carried out. Km value of immobilized β-glucosidase was calculated as 47.7 ± 0.7 mM, and Vmax value was 34.6 ± 0.5 U/mg. Under optimized condition, which was 45 °C, pH 6.0, with the initial polydatin concentration of 2.0%, and the flow rate of 1.0 mL/min, the overall hydrolysis yield could reach 85.8 ± 0.6%, and the activity of the immobilized enzyme remained 92.2 ± 0.9% after continuous hydrolysis for 8 h. Enzymatic hydrolysis of polydatin extracted from P. cuspidatum is a promising method to increase the supply of resveratrol in pharmaceutical markets worldwide, which also showed a new application of immobilized β-glucosidase in biotechnological industry.