八月瓜种子的化学成分及其α-葡萄糖苷酶抑制活性

Chemical Composition andα-Glucosidase Inhibitory Activity of the Seeds of Akebia trifoliata

该研究探讨了药食两用八月瓜种子[Akebia trifoliata(Thunb.)Koidz.Seeds]的化学成分及其α-葡萄糖苷酶抑制活性。将八月瓜种子经水和95%乙醇提取,不同极性溶剂萃取后,分别测试各部位的α-葡萄糖苷酶抑制活性,发现95%乙醇提取物的正丁醇部位为α-葡萄糖苷酶抑制活性部位(IC_(50)为18.16μg/mL),采用硅胶柱色谱、HP20SS柱色谱和半制备HPLC等手段对正丁醇部位进行分离纯化。从八月瓜种子正丁醇部位中分离得到14个化合物,通过与文献波谱数据对比,分别鉴定为:Hederacholichiside F(1)、Saponin E(2)、Mutong Sponin B(3)、Saponin PJ1(4)、Saponin PH(5)、YuzhiziosideⅣ(6)、Akebia Saponin D(7)、Saponin B(8)、HN-Saponin F(9)、YuzhiziosideⅣa(10)、Icariside D(11)、Phenethyl rutinoside(12)、Calceolariolside B(13)和Isoquercitrin(14)。化合物9、10、11、12、14为首次从八月瓜中分离得到。化合物2、7、10、14对α-葡萄糖苷酶具有一定程度的抑制活性,其IC_(50)分别为17.48、35.62、35.79、44.78μg/mL。化合物6、13的抑制活性最为显著,其IC_(50)分别为4.27、2.95μg/mL,活性优于阳性药阿卡波糖(IC_(50)为6.02μg/mL)。

In this study,the chemical constituents andα-glucosidase inhibitory activity of medicine and food dual-use Akebia trifoliata(Thunb.)Koidz.Seeds were studied.The seeds of Akebia trifoliata were extracted with water and 95%ethanol,then extracted with different polar solvents.Theα-glucosidase inhibitory activity of each of these extract fractions was determined.It was found that the n-butanol fraction of the 95%ethanol extract could inhibit the active site of theα-glucosidase(IC_(50) was 18.16μg/mL).The n-butanol fraction was separated and purified by silica gel column chromatography,HP20SS column chromatography and semi-preparative HPLC.Fourteen compounds were isolated from the n-butanol fraction of Akebia trifoliata seeds, and after the comparison with the spectral data in the literature, they were identified as Hederacholichiside F (1), Saponin E (2), Mutong Sponin B (3), Saponin PJ1 (4), Saponin PH (5), Yuzhiziosiside IV (6), Akebia Saponin D (7), Saponin B (8), HN-Saponin F (9), Yuzhizioside Ⅳa (10), Icariside D (11), Phenethyl rutinoside (12), Calceolariolside B (13) and Isoquercitrin (14). Compounds 9, 10, 11, 12 and 14 were isolated from Akebia trifoliata for the first time. Compounds 2, 7, 10 and 14 had certain inhibitory activities against α-glucosidase with IC_(50) values being 17.48, 35.62, 35.79 and 44.78 μg/mL, respectively. Compounds 6 and 13 showed the most significant inhibitory activities, with IC_(50) values being 4.27 μg/mL and 2.95 μg/mL, respectively, which were superior to that of acarbose (IC_(50): 6.02 μg/mL).