Abstract
An immobilization method of enzyme in acylchitosan gel as a novel support, which was prepared by the reaction of chitosan with carboxylic anhydride in aqueous solution of carboxylic acid, was investigated. Invertase was immobilized in acylchitosan gel using the bifunctional agent, glutaraldeahyde. The most active preparation is based on the enzyme bound acetylchitosan gel with degree of substitution of acetyl groups of 1.05. Its activity yield was 37.7% after incubation at pH 4.2 for 20 min, using sucrose as substrate. The optimum pH was shifted to acidic side as the result of the immobilization. The optimal temperature of gel-immobilized enzyme was 60°C, and higher than that of native enzyme (50°C). The activity of gel bound enzyme through the column showed no significant drop even after being used over 20 days.
