鹧鸪茶提取物抗氧化活性研究与抗氧化特征成分的HPLC-MS/MS分析

Antioxidant activity study and HPLC-MS/MS analysis of antioxidant characteristics of Mallotus oblongifolius extract

采用DPPH体系、ABTS体系和Oyaizu法对鹧鸪茶的甲醇提取物、70%乙醇提取物和水提取物的抗氧化活性进行了测定,并利用HPLC-MS/MS对活性较高的乙醇提取物的抗氧化特征性成分进行了分析。结果表明:鹧鸪茶3种提取物均具有一定的抗氧化能力,呈剂量效益关系。其中3种提取物中以70%乙醇提取物对DPPH和ABTS清除能力最强,而还原力则弱于水提取物和强于甲醇提取物。通过HPLC-MS/MS从70%乙醇提取物中得到7个酚类物质,其中3个酚类物质被鉴定为阿魏酸甲酯、儿茶素和槲皮素。

The antioxidant activity of methanol, 70% ethanol and water extract of Mallotus oblongifolius was determined by using methods of three complementary in vitro assays： the DPPH radical-scavenging activity, the ABTS radical-scavenging activity, and reducing ability. And the antioxidant characteristics of 70% ethanol extract were analyzed by HPLC-MS/MS. In vitro antioxidant assays showed that the three extracts showed varying degrees of efficacy in each assay in a dose-dependent manner. 70% ethanol extract exhibited the strongest DPPH radical-scavenging ability with IC50 value of 0.184 mg/mL and ABTS radical-scavenging ability with IC50 value of 0.015 mg/mL in the three extracts, while it showed lower reducing ability than water extract and higher than methanol extract. Seven main constituents in the 70% ethanol extract were obtained by HPLC-MS/MS, and the three major polyphenols identified were methyl ferulate, gallic acid and quercetin.