Abstract：
The present study evaluated the potential of endogenous enzymes and probiotics in transforming bioactive metabolites to reduce the purgative effect and improve the functional activity of Cassiae Semen and verified and revealed the biotransformation effect of endogenous enzymes. Although probiotics, especially Lactobacillus rhamnosus, exerted the transformation effect, the endogenous enzymes proved to be more effective in transforming the components of Cassiae Semen. After biotransformation by endogenous enzymes for 12 h, the levels of six anthraquinones in Cassiae Semen increased by at least 2.98-fold, and free anthraquinones, total phenolics, and antioxidant activity also showed significant improvement, accompanied by an 82.2% reduction in combined anthraquinones responsible for the purgative effect of Cassiae Semen. Further metabolomic analysis revealed that the biotransformation effect of endogenous enzymes on the bioactive metabolites of Cassiae Semen was complex and diverse, and the biotransformation of quinones and flavonoids was particularly prominent and occurred by three primary mechanisms, hydrolyzation, methylation, and dimerization, might under the action of glycosyl hydrolases, SAM-dependent methyltransferases, and CYP450s. Accordingly, biotransformation by endogenous enzymes emerges as a mild, economical, food safety risk-free, and effective strategy to modify Cassiae Semen into an excellent functional food.
摘要：
本研究评估了内源性酶和益生菌在转化生物活性代谢产物以降低泻药效应和提高决明子功能活性方面的潜力，并验证和揭示了内源性酶的生物转化作用。虽然益生菌，尤其是鼠李糖乳杆菌,发挥了转化效应，内源性酶被证明在转化决明子精液的成分方面更有效。内源性酶生物转化12小时后，决明子中6种蒽醌的水平至少增加了2.98倍，和游离的蒽醌,总酚类物质，抗氧化活性也有显著提高,伴随着对决明子的泻药作用的联合蒽醌减少了82.2％。进一步的代谢组学分析显示,内源酶对决明子生物活性代谢产物的生物转化作用是复杂多样的,醌类和类黄酮的生物转化尤为突出，主要通过三种机制发生，水解，甲基化,和二聚化，可能在糖基水解酶的作用下，SAM依赖性甲基转移酶，和CYP450。因此，内源性酶的生物转化表现为温和的，经济,食品安全无风险,和有效的策略，将决明子精液改造成一种优良的功能食品。
