茜草抑制α-葡萄糖苷酶活性成分研究

目的:寻找茜草中抑制α-葡萄糖苷酶活性的成分.方法:利用体外抑制α-葡萄糖苷酶活性模型进行追踪,采用各种色谱法分离,运用多种谱学技术鉴定结构,并对活性化合物进行酶抑制动力学研究.结果:茜草三氯甲烷提取物具有很高的活性,从中分离出3个具抑制α-葡萄糖苷酶活性的蒽醌类化合物,分别鉴定为:1,3-二羟基-2-甲基蒽醌(1),1-羟基-2一甲基葸醌(2)和1,2-二羟基蒽醌(3),其中化合物3(IC_(50)=7.97 mg·L~(-1))活性最好,与1(IC_(50)=35.96 mg·L~(-1))和2(IC_(50)=15.98 mg·L~(-1))的活性都明显高于阳性对照阿卡波糖(IC_(50)=1 081.27 mg·L~(-1)).化合物1和2为竞争性抑制类型.结论:化合物1-3为首次报道对α-葡萄糖苷酶抑制活性.

α-Glucosidase inhibitors from Rubia cordifolia

Objective: To search α-glucosidase inhibitors from Rubia cordifolia.  Methed: The α-glucosidase inhibitors were isolated by the column chromatographic techniques and the bioassay-guided method in vitro. A combination of MS and NMR spectroscopy was used to identify the chemical structures. The inhibitory kinetics of the inhibitors were also investigated.  Result: The chloroform extract showed high inhibitory activity,and three active compounds were isolated and identified as 1,3-dihydroxy-2-methylanthraquinone (1), 1-hydroxy-2-methylanthraquinone (2) and 1,2-dihydroxyanthraquinone (3). The IC50 values of compound 1-3 were all lower than that of acarbose. Compound 1 and 2 shown competitive type manner on α-glucosidase,whereas compound 3 shown noncompetitive type model.  Conclusion:  Compounds 1-3 as strong inhibitors of α-glucosidase were reported for the first time.