Biotransformation of Soybean Isoflavone by Microbial Solid-state Fermentation

Soybean insoflavones(SIF) are rich in nutritional value and heathy benefit,which had been widely applied in various fields including food,feed,medicine and so on.To extend the application of SIF for industrialization production,the efficacy of biotransformation of SIF by microbial solid-state fermentation was studied using EM strains,Bacillus subtilis ATCC 6633 and Lactobacillus planetarium ATCC 8014 for single and mixed fermentation.Effects of combined strains and incubation size were investigated for improve the biotransformation efficiency of SIF through vacuum sealed fermentation.The repeatability of the samples was also investigated under the optimized fermentation conditions.The results demonstrated that the single strain-mediated fermentation resulted in higher biotransformation efficacy than that with mixed strains,and the ratio of aglycone in total SIF content reached 64.56% after 7 d by solid-state fermentation with Bacillus subtilis ATCC 6633.The fermentation had high repeatability and stability.