Studies on Preparation and Properties of Pectinase Immobilized with Chitosan and Glutaraldehyde

Pectinase from Aspergillus niger was immobilized with 1 % chitosan and crosslinked with 5 % glutaraldehyde for 8 hours. Ten milligramme pectinase for one gramme crosslinked carrier. The process time was 12 h at 4 ℃ after 30-minute oscillation and mix for enzyme and carrier under pH 3.4 of reaction medium. The results showed the strength and toughness of immobilized enzyme was good enough and the recovery rate of enzyme activity could retain up to 56.31 %. The optimum pH and temperature of immobilized pectinase for the hydrolysis of pectin were determined to be pH3.4 and 50℃, respectively. And the apparent Michaelis constant of immobilized pectinase Kmapp equaled to 5.42 mg·mL-1. The recovery activity of immobilized pectinase was more than 70.45 % after repeated seven times, which exhibited better operational stability.