纳豆制备过程中大豆异黄酮的转化条件

使用日本古法制备纳豆,从纳豆中分离筛选出高活性的纳豆菌为实验菌株。研究了纳豆制备过程中大豆异黄酮的转化情况,发酵液中的大豆异黄酮在大豆异黄酮糖苷酶的水解作用下水解掉侧链糖基,转化为活性更高的大豆异黄酮苷元。根据薄层层析法确定了大豆异黄酮转化为大豆异黄酮苷元的最佳培养条件:培养温度为37℃,培养时间2 d,pH 7.0,含水质量分数60%。发酵液中大部分的大豆异黄酮苷转化为大豆异黄酮苷元,从而得到更利于人体吸收的大豆异黄酮苷含量较高的纳豆制品。

Conversion of soybean isoflavone in natto fermentation

Bacillus natto isolated from the traditional Japanese natto was used for the conversion of soybean isoflavone into soy isoflavone aglycone catalyzed by isoflavone-glucosidase.The conversion of the soybean isoflavone was determined and the optimum condition is: the temperature was 37 ℃,fermentation time was 2 d,pH=7.0,and the water content was 60%.Most of the soybean isoflavone were transformed into soy isoflavone aglycone under the better condition.