Applied Biochemistry and Biotechnology, Vol.127, No.3, 157-171, 2005
Preparation of trehalase inhibitor validoxylamine a by biocatalyzed hydrolysis of validamycin A with honeybee (Apis cerana Fabr.) beta-glucosidase
Validoxylamine A is structurally similar to trehalose and acts a potent competitive inhibitor of trehalase. It has recently been receiving increased attention as a potential material for the development of new insecticides or drugs. In this study, beta-glucosidase extracted from honeybees (Apis cerana Fabr.) was used as a catalyst to produce validoxylamine A through enzymatic hydrolysis of validamycin A. beta-Glucosidase was separated and purified from honeybees, and its characteristics were examined. The results showed that P-glucosidase was stable across a range of temperatures from 30 to 40 degrees C and across a relatively wide range of pH values from 5.0 to 7.5. Investigation of the biocatalyzed hydrolysis process from validamycin A to validoxylamine A with P-glucosidase revealed that both the substrate (validamycin A) and the product (validoxylamine A) inhibited P-glucosidase activity. The inhibition constant of the substrate K-is value was 5.01 mM, and that of the product K-ip value was 1.32 mM. This product inhibition was competitive.