Immobilized beta-glucosidase from Curvularia lunata

beta-Glucosidase from Curvularia lunata was immobilized in pellets of polyacrylamide, sodium alginate and agar. The activity of the enzyme was estimated at different times by measuring the absorbance of a solution into which 2-nitrophenol was released by the enzyme. The effect of pH and temperature was studied to select the optimum conditions. Thermostability of the beta-glucosidase in each of the carriers was assessed over a period of 12-26 d. The immobilized enzyme on all the three carriers retained its activity longer than free enzyme did. Polyacrylamide was the best carrier both in terms of thermostability and of reusability of the immobilized enzyme preparations. The Michaelis constant (Km) for each of the immobilized enzyme preparation was calculated.