Stability of Enzyme Activity Immobilized on Glycosylated Egg White Beads and Some General Carriers in a Flow System

Abstract

Ttypsin and α-amylase were immobilized on glycosylated egg white-beads by simple incubation of the beads in a solution of an enzyme for 24 h at 30°C. This process included no artificial chemical modification. The obtained immobilized enzymes had a longer lifetime in continuous operation than those of the enzyme immobilized on cation exchanger or chitosan beads. The stability of the immobilized amylase was comparable with that of the enzyme immobilized on cyanogen bromide activated agarose-beads for which inactivation was not observed. The causes of the inactivation of these various types of immobilized enzymes were examined by enzyme leakage analysis from a chamber packed with the immobilized enzymes and by enzyme activity analysis by a pH-stat method. Enzyme leakage from the immobilized trypsin caused inactivation of the egg white beads and the cation exchanger, while coverage of the bead surface with substrate was the reason for inactivation of the chitosan beads. Almost no inactivation was observed for immobilized amylase.