大叶榄仁叶化学成分及其降糖活性

Chemical constituents from the leaves of Terminalia catappa and their hypoglycemic activities

目的研究大叶榄仁叶的化学成分及其降糖活性。方法大叶榄仁叶80%乙醇提取液采用硅胶柱、反相ODS柱、HP-20、Sephadex LH-20进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构。通过检测对α-淀粉酶的抑制作用评价多酚单体的降糖活性。结果从中分离得到12个化合物,分别鉴定为没食子酸(1)、间-二没食子酸甲酯(2)、没食子酸甲酯(3)、没食子酸乙酯(4)、3,3'-二甲基鞣花酸(5)、鞣花酸(6)、3,3',4-三甲基鞣花酸-4'-O-β-D-葡萄糖苷(7)、3-甲基鞣花酸(8)、没食子酸正丁酯(9)、4-O-乙基没食子酸(10)、1,2-没食子酰丙三醇(11)、robinlin (12)。没食子酸正丁酯对α-淀粉酶抑制作用显著。结论化合物2、4、7、10～12为首次从榄仁属植物中分离得到。多酚类成分具有较好的降糖活性。

AIM To study the chemical constituents from the leaves of Terminalia catappa L. and their hypoglycemic activities. METHODS The ethyl acetate fraction of 80% ethanol extract from the leaves of T. catappa was isolated and purified by silica column,reversed-phase ODS column,HP-20 and Sephadex LH-20,then the structures of obtained compounds were identified by physicochemical properties and spectral data. The hypoglycemic activities of the polyphenols were evaluated by α-amylase inhibitory test. RESULTS Twelve compounds were isolated and identified as gallic acid(1),methyl-digallate(2),methyl gallate(3),ethyl gailate(4),3,3’-dimethylellagic acid(5), ellagic acid(6),3,3’,4-trimethylellagic acid-4’-O-β-D-glucoside(7),3-methylellagic acid(8),n-butyl gallate(9),4-O-ethylgallic acid(10),1,2-O-di-galloylglycerol(11),robinlin(12). N-butyl gallate exhibited good inhibitory activity in α-amylase inhibitory test. CONCLUSION Compounds 2,4,7,10-12 are isolated from genus Terminalia for the first time,the polyphenols have good hypoglycemic activities.