Glucoamylase immobilized on acid-hydrolyzed starch graft polyacrylonitrile.

A continuous stirred reactor fed maltose as substrate was used to show that acid hydrolyzed starch-g-polyacry-lonitrile and other polysaccharide graft copolymers can bind and retain significant quantities of active glucoamy-lase. Glucose productivities up to 2.7 g/g carrier/h were observed with the immobilized glucoamylase, and half-lives up to 1800 h were indicative of activity longevity. Factors influencing the immobilized enzyme activity and first-order decay rate included temperature, p(H), and carrier composition. In all cases, maltose was converted quantitatively to glucose with no evidence of reversion product formation.