地肤子中抗氧化活成分筛选

Screening Chemical Constituents with Antioxidative Activity from the Kochiae Fructus

目的研究地肤子的抗氧化活性成分,确定其抗氧化活性物质基础。方法以DPPH自由基清除率试验为手段,对地肤子石油醚相、乙酸乙酯相、正丁醇相和水相四个部位进行抗氧化活性筛选。用多种柱色谱结合重结晶的方法对抗氧化活性强的部位进一步分离,通过化合物的理化性质结合波谱分析鉴定分离得到化合物的结构,并测试其对DPPH自由基的清除率,以IC50值为指标,判断其抗氧化活性。结果正丁醇相是地肤子的抗氧化活性部位,从中分离得到4个单体化合物:齐墩果酸(1)、胡萝卜苷(2)、槲皮素-3-O-β-D-葡萄糖苷(3)和金丝桃苷(4),其中化合物(3)是首次从地肤子中分离得到。与阳性对照维生素C相比,化合物3和化合物4的抗氧化活性较强,其IC50值分别为13.86和21.03μg/ml。结论地肤子抗氧化活性的物质基础主要为其所含丰富的黄酮类物质。

Objective To study the antioxidant active ingredients and clarify the basis of its antioxidant active substances from the Kochiae Fructus.Methods The DPPH free radical scavenging test is used as a means to screen the antioxidant active fractions from the Kochiae Fructus.The compounds from the antioxidant active fractions are isolated and purified by column chromatography and recrystallization methods.Their structures are identified by their physicochemical properties and spectral analysis.The compounds with good antioxidant activity are screened by DPPH free radical scavenging test.Results N-butanol fraction show significant anti-oxidant activity,and four compounds are obtained from it.The four compounds are identified as followed:Oleanolic acid(1),daucosterol(2),quercetin-3-O-α-D-glucosylside(3),hyperin(4).The compound 3 is first isolated from the Kochiae Fructus.Compared with the positive control vitamin C,compound 3 and compound 4 had strong antioxidant activities,their IC50 values are 13.86 and 21.03μg/ml.Conclusion The flavonoids contained in the Kochiae Fructus are the main material basis of their antioxidant protein.