Physicochemical Properties of Niigata Waxy Rices

The crude lipase powder has been purified 216-fold in specific activity by means of pH adjustment, DEAE-Cellu1ose, DEAE-Sephadex A-50, CM-Sephadex C-50 and Sephadex G-200 column chromatography and the recovery of the activity was 30%. The purified lipase was confirmed to be homogeneous with disc electrophoresis and ultracentrifugal analyses. The purified lipase was stable in the pH range from 7.0 to 10.0. Optimal pH for the lipolysis of polyvinyl alcohol-emulsified olive oil at 45°C was 8.0 and optimal temperature was 60°C. The purified lipase was stable up to 60°C and retained 55% of full activity after heating at 70°C for 20 min.