| Abstract: | Pullulanase was immobilized on tannic acid and TEAE-cellulose, and β-amylase was covalently immobilized on p-aminobenzylcellulose. Both the immobilized enzymes showed similar properties in pH and temperature optima and heat stability. On passing the pullulan solution at high temperature (50°C) through a column packed with immobilized pullulanase, only maltotriose was obtained for ten days and the half-life was about 15 days. In a continuous reaction using immobilized multienzyme, starch was completely converted into maltose at 50°C and at a space velocity of 1.2, a comparative longer half-life (20 days) was obtained. It was concluded that starch was smoothly converted into maltose with the aid of α-amylase contaminated in the immobilized pullulanase and the operational stability of the column increased with 2-5mM Ca2+. |
