SOD-like Activities of Rice Bran Extracts after Fermentation

To make a good use of rice bran that has been treated as a kind of industrial waste, we have tried to ferment the rice bran by typical microorganisms such as yeast, and to extract ingredients with antioxidative activity. The antioxidative activity was estimated as a SOD-like activity. The SODlike activities of the rice bran extracts after fermentation by using ESR spectroscopy by baker's yeast and whisky yeast significantly increased in comparison with that of rice bran extract without fermentation. The components in the rice bran extracts after fermentation participating in the SOD-like activity were suggested to be kinds of protein. We estimated the molecular weights of the proteins precipitated with ammonium sulfate, using a HPLC. Based on the results obtained from the HPLC measurements, the proteins with a SOD-like activity various molecular weights exist in rice bran extracts after fermentation. The proteins with a SOD-like activity may be composed with the other components such as polyphenol and sugar, having a SOD-like activity. (Received Jul. 16, 1999; Accepted Nov. 8, 1999)