Immobilization of amylase onto arylamine glass beads affixed inside a plastic beaker: Kinetic properties and application

Commercial fungal amylase (diastase) has been immobilized through diazotization onto zirconia coated arylamine glass beads, affixed inside a plastic beaker. The immobilized enzyme retained 73.3% of the initial activity of free enzyme with a conjugation yield of 8 mg/g. Optimum pH of enzyme was decreased, while temperatures for maximum activity, energy of activation, time of incubation and Km for starch were increased after immobilization. The utility of immobilized enzymes in removal of starch stain from cotton cloth by various detergents was tested by chemical method. All the detergents gave better washing in presence of immobilized amylase than that by detergent alone. Further, the washing by cheaper (non-enzymic) detergents in presence of immobilized amylase was almost similar to that by expensive (enzymic) detergents. The immobilized enzyme was used about 100 times without any considerable loss of activity.