Immobilization of enzymes based on hydrophobic interaction. I. Preparation and properties of a beta-amylase adsorbate.

Sweet potato beta-amylase (alpha-1,4 glucan maltohydrolase, EC 3.2.1.2) was immobilized through adsorption onto an agrose gel to which nonpolar side chains had been introduced via ether bridges. The adsorbent showed evidence of saturation at an enzyme content of 35 mg per milliliter of packed gel. The adsorption was rapid and yielded a product whose operational stability depended on the initial content of beta-amylase. Activity leakage was low. The relative activity of immobilized enzyme was inversely related to the amount of enzyme adsorbed to a given gel volume, having a maximal value of around 50% at low enzyme contents.