Antioxidant activity of Arctium lappaL.seed extracts

【Objective】 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.【Method】 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 O-·2 based on different concentrations of different solvent extracts of burdock was measured,and the antioxidant activities of the four extracts were compared.【Result】 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,O-·2 scavenging activity of acetone extract were the highest.【Conclusion】 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.