Transformation Of Active Ingredients In Soybean Formentation

The microbial conversion of soybean isoflavones and soybean saponin,and the preparation of fermented soybean products were studied in this paper.The transformation of soybean isoflavones and soybean saponin in defatted soya bean meal was compared by using Bacillus natto and Aspergillus oryze sp.3042.The fermented soybean products with high content of high activity soybean isoflavones and soybean sapanin was prepared.The Results are as follows:The raw material of soya bean meal was extracted by 75%ethanol and then extracted by ethyl acetate and saturated butanol orderly,soybean isoflavones and soybean saponin was obtained and the yield was 0.25%and 2.90%respectively.The conversion of soybean isoflavones and soybean saponin by Aspergillus oryze sp.3042 was better than that by Bacillus natto.Aspergillus oryze sp.3042 was fermented in defatted soy flour to transforme the bioactive substance of soybean isoflavones and soybean saponin.The optimum condition of transformation was:moisture content was 50%;temperature was 28?;fermentation time was 4d.Transformational soybean isoflavones and lower sugar soybean saponin was detected by TLC and HPLC.The extraction ratio of them was 0.39%and 0.17%,the percent conversion of them was 90%and 50%respectively.That underlies the production of the two bioactive substances.The preparation of fermented soybean products which contain high content and high activity of bioactive substance was discussed.When fermented soya bean meal and rice used for make soybean paste,the optimum temperature was 30?;fermentation time was 30d.When fermented soya bean meal and rice used for make sweet flour paste,the optimum temperature was 50 ?;fermentation time was 15d.The typical properties of the two productions met the national standards and can be novel fermented soybean products.