Antioxidant activity of Arctium lappa L. seed extracts | 牛蒡子提取物的抗氧化活性研究

chinois. 评价牛蒡子不同溶剂提取物的抗氧化能力，为揭示牛蒡子的部分药用机理及其进一步开发利用提供参考。用极性逐渐增大的氯仿、乙酸乙酯、丙酮、乙醇溶剂对牛蒡子粗粉进行超声波提取，经旋转蒸发仪浓缩、干燥后得到粗提物。然后，分别将以上4种提取物溶解于甲醇中,配制成质量浓度分别为0.1，0.25，0.5，1，2，3，4，5 mg/mL的溶液，将阳性对照BHT配制成质量浓度分别为0.01，0.025，0.05，0.1，0.25，0.5，1，2，4 mg/mL的溶液，测定不同溶剂提取物在不同质量浓度下对DPPH•、•OH 、H2O2和O2-•活性的清除率，并以IC50值为指标，比较4种牛蒡子提取物的抗氧化能力。牛蒡子氯仿提取物、乙酸乙酯提取物、丙酮提取物、乙醇提取物和BHT清除DPPH自由基的IC50值分别为10.01，19.96，1.82，0.30和0.93 mg/mL，清除•OH自由基的IC50值分别为4.77，5.10，2.85，4.13和0.47 mg/mL，清除H2O2的IC50值分别为2.28，2.51，2.17，1.37和0.13 mg/mL，清除O2-•的IC50值分别为5.02，6.12，2.80，3.89和3.01 mg/mL。牛蒡子不同溶剂提取物中，乙醇提取物清除DPPH•和H2O2的能力较强，丙酮提取物清除•OH和O2-•的能力较强。牛蒡子的不同溶剂提取物均具有抗氧化活性，但除乙醇提取物清除DPPH•的能力、丙酮提取物清除O2-•（质量浓度大于3 mg/mL）的能力高于阳性对照BHT外，其他溶剂提取物的抗氧化活性均低于BHT。

anglais. The comprehensive estimate about antioxidant activity of Arctium lappa L. seed extracts was determined to provide theoretical basis for study of the medicinal mechanism and further development and utilization of burdock. The elementary extract was extracted by solvents of chloroform, ethyl acetate, acetone, ethanol with the polarity increasing from the powder of the seeds separately using sonication, concentrated and dried by rotary evaporator. Then, the above four extracts were dissolved in methanol at a concentration of 0.1, 0.25, 0.5, 1, 2, 3, 4 and 5 mg/mL. Similarly, the concentrations of BHT were 0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1, 2, 4 mg/mL. Using BHT as the positive control, the scavenging activity of DPPH•,•OH, H2O2 and O2-• based on different concentrations of different solvent extracts of burdock was measured, and the antioxidant activities of the four extracts were compared. The IC50 values of DPPH• scavenging of chloroform extract, ethylacetata extract, acetone extract, ethanol extract and BHT were 10.01, 19.96, 1.82, 0.30, 0.93 mg/mL; the IC50 values of•OH scavenging were 4.77, 5.10, 2.85, 4.13, 0.47 mg/mL; the IC50 values of H2O2 scavenging were 2.28, 2.51, 2.17, 1.37, 0.13 mg/mL; the IC50 values of superoxide anion radicals scavenging were 5.02, 6.12, 2.80, 3.89,3.01 mg/mL. Among the four extracts, the DPPH•, H2O2 scavenging activity of ethanol extract and •OH, O2-• scavenging activity of acetone extract were the highest. The four extracts of burdock seed have the antioxidant activity, but the antioxidant activity of other extracts is lower than the positive control BHT except that the scavenging activity of DPPH• of ethanol extract and O-•2 of acetone extract is higher than BHT, when the concentration is greater than 3 mg/mL.