Preparation and characterization of amyloglucosidase adsorbed on activatedcharcoal

Amyloglucosidase (AMG) [alpha-1, 4-D-glucan glucohydrolase (E.C.3.2.1.3)] i s an exo-enzyme, which is used in the hydrolysis of starch to glucose in in dustries. To increase the efficiency and profitability of this process, AMG was immobilized on activated charcoal by physical adsorption without the a id of any cross-linking agent, characterized by hydrolysis of dextrin and c ompared with the native enzyme. The immobilized enzyme has 90% catalytic ac tivity of the native enzyme. Optimum pH of the immobilized enzyme was six, which shifted to basic side by one unit when compared to the optimum pH of the native enzyme (5.0). Optimum temperature of the immobilized enzyme was 60 degrees C, decreased by 10 degrees C when compared to optimum temperatur e (70 degrees C) of the native enzyme. K-m(app) and V-max(app) values of im mobilized enzyme were found to be 1.0 x 10(-3) g/l and 3.8 x 10(-4) g/min/u nit of enzyme, respectively which were less than the values of the native e nzyme. The immobilized system can be used repeatedly and continuously for a longer period of time. (C) 2000 Elsevier Science S.V. All rights reserved.