抄録
1) Aspergillus terreus No. 9A-1 was cultivated by a shaking method and the optimal cultural conditions for the phytase production were concluded as follows: Composition of medium; rice bran 30g, ammonium sulfate 3g, distilled water 1.0 liter; initial pH 5.5; shaking condition; 50ml of medium/500ml vol. flask; 120 oscil./min, 90hr.
2) Phytase from Asp. terreus was purified by ammonium sulfate precipitation, acetone precipitation and chromatography on SE-Sephadex C-50 and Sephadex G-200 columns. The enzyme was purified about 520-folds with the yield of 20% from the broth. The purified enzyme was homogeneous by column chromatography, ultracentrifugation and electrophoresis.
3) This purified preparation of phytase showed following properties. a) Optimal pH for the reaction was 4.5; b) optimal temperature for the reaction was about 70°C; c) the enzyme was stable in the range of pH from 1.2 to 9.0