不同发酵条件对淡豆豉中总异黄酮含量及蛋白酶活力的影响

Effect of different fermentation strains on total isoflavone content and Protease activity in semen sojae praeparatum

目的:建立淡豆豉中总异黄酮的含量测定方法,研究不同发酵条件对淡豆豉中总异黄酮及蛋白酶活力的影响。方法:采用UV法,以染料木素为标准品,在最大吸收峰261 nm处测定黑豆、自然发酵的淡豆豉、米曲霉发酵的淡豆豉、黑曲霉发酵的淡豆豉中总异黄酮含量;以福林法测定蛋白酶活力。结果:黑豆中的总异黄酮的含量为7.77mg·g^(-1),自然发酵淡豆豉总异黄酮为8.08 mg·g^(-1),米曲霉发酵淡豆豉总异黄酮为8.87 mg·g^(-1),黑曲霉发酵淡豆豉总异黄酮含量为10.99 mg·g^(-1)。平均加样回收率100.09%,100.34%,99.76%,99.87%,相对标准偏差为为1.10%,1.28%,1.22%,1.24%。酶活力测定结果为:黑豆190.7 U·g^(-1)、自然发酵淡豆豉309.4 U·g^(-1),米曲霉发酵淡豆豉474.9 U·g^(-1),黑曲霉发酵淡豆豉500.0 U·g-1。结论:UV法作为检验淡豆豉中异黄酮含量的一种手段,方法简便、准确、重现性好。单一菌种发酵淡豆豉异黄酮含量和酶活力均高于黑豆和自然发酵淡豆豉。

Objective：A UV spectrophotometry used for determination of semen sojae praeparatum isoflavones was established.The effects of different fermentation strains on the content of total isoflavones and protease activity in the fermentation products was studied.Methods：Genistein was selected as the reference substance.Contents of the isoflavones in black bean and semen sojae praeparatum by natural fermentation,Aspergillus oryzae fermentation,Aspergillus niger fermentation at the maximum absorption peak.Folin method was used for determination of protease activity.Results：The total content of isoflavones in black bean was 7.77 mg·g^-1,natural fermentation products was 8.08 mg·g^-1,Aspergillus oryzae fermentation products was 8.87 mg·g^-1,Aspergillus Niger fermentation products was 10.99 mg·g^-1,average recovery was 100.09%,100.34%,99.76%,99.87%,and the RSD was 1.10%,1.28%,1.22%,1.24%.The enzyme activity of black beans was 190.7 U·g^-1,natural fermentation products was 309.4 U·g^-1,Aspergillus oryzae fermentation was 474.9 U·g^-1,Aspergillus Niger fermentation was 500.0 U·g^-1.Conclusion：UV method as a means of inspection semen sojae praeparatum isoflavone content with easy—to—handle,good accuracy and reproducibility.The single strain fermentation of semen sojae praeparatum,in enzyme activity and isoflavone content respects,were higher than the natural fermentation products and black bean.