Studies on rice seed protease V. Protease inhibitor in rice seed1

摘要

Protease inhibitor in rice seed was investigated physiologically in connection with rice seed protease. In rice seed, the inhibitor was localized in the embryo and its activity decreased on germination. The inhibitor was a protein-like substance which, was non-diffusible through cellophane membrane, salted out on addition of ammonium sulfate, was denatured on heating it at 100°C and adsorbed onto ion-exchange cellulose. During incubation at 70°C for 30 min, inhibitor activity remained unchanged, while the protease lost its activity within 10 min. The protease and the inhibitor of rice seed were separated from each other by chromatography on a TEAE-cellulose column. The inhibitor reduced the activity of rice seed proteas