纳豆菌糖苷酶水解大豆异黄酮的条件优化

为得到生物活性较高的大豆异黄酮苷元,研究了纳豆菌所产糖苷酶水解大豆异黄酮的条件。通过薄层层析(TLC)检测,选择单因素条件。在单因素试验的基础上,进行四因素三水平的正交试验。结果表明,最佳水解条件为:水解温度40℃,水解时间3 h,底物质量浓度2 mg/mL,酶底体积比2∶1,在此条件下,水解率为84.65%。经HPLC检测,与染料木素标准品谱图对照,发现在糖苷酶水解作用下,大豆异黄酮糖苷很大程度上转化为苷元,且染料木素的含量显著增加。

Optimal hydrolysis of soybean isoflavone with glycosidase from Bacillus natto

The hydrolysis of soybean isoflavone with glycosidase from Bacillus natto was studied.The condition of single-factor experiment was chosen by TLC.Orthogonal test was carried out based on single-factor experiment.The results showed that the optimal hrdrolysis were hydrolysis temperature 40 ℃,hydrolysis time 3 h,substrate concentration 2 mg/mL,enzyme-substrate ratio 2∶1.The hydrolysis rate was 84.65% at the optimal conditions.It was found that soybean isoflavone glycosides were converted to isoflavone alycones with glycosidase.Genistein increased significantly.