Abstract: To exploit the isoflavone as natural food antioxidant and antiseptic in fermented soybean meal, the antioxidative and antimicrobial activities of isoflavone extracted from fermented soybean meal (FSMI) were studied. The results showed that FSMI had antioxidant effect on soybean and rapeseed oil, which was better than isoflavone from soybean meal (SMI) and BHT in the same concentration. The research also discovered that the minimal inhibition concentrations of FSMI were 0.24% against bacteria, and 0.56% against fungi, the antimicrobial activities of the FSMI were superior to SMI and sodium benzoate.

Key words: FSMI, antioxidative activities, antimicrobial activities, natural food additives