Evaluation of Antioxidant Activities in Vitro of Ethanol Extract from Perilla frutescens(L.)Britt Leaves and Correlation Analysis

Six different kinds of methods to evaluate the antioxidant activities,including intracellular reactive oxygen species scavenging abilities(CAA),total antioxidant activities(TAA),scavenging superoxide anion radical(SSAR),scavenging hydroxyl radical(SHR),scavenging 1,1-diphenyl-2-picrylhydrazyl radical(SDR)and inhibition of lipoprotein lipid peroxidation(ILLP)were used to evaluate the antioxidant activities in vitro and free radical scavenging abilities of Perilla fruescens Britt leaves,ethanol extract(WPEE),which were compared with antioxidant activity of ascorbic acid(V_C).The results showed that six kinds of methods all indicated that WPEE had significant antioxidant activities. The order of TAA,SSAR and SDR was V_C > F₂ > WPEE > F₁(F₁ and F₂ were the main components 1 and 2 of WPEE),while the order of SHR and ILLP was F₂ > WPEE > V_C > F₁.In addition,WPEE was non-cytotoxic to RAW264.7 cells and had a good scavenging ability of reactive oxygen species(ROS)within the concentration range of 1~500 μg/mL. Pearson correlation analysis showed that the six kinds of methods of evaluating antioxidant activity were all limited,which evaluated different aspects of antioxidant activity. Except for ILLP and SSAR,the other four kinds of methods to evaluate antioxidant activity had a good correlation with each other. The antioxidant activity was positively correlated with the concentration of WPEE,indicating that WPEE was a broad-spectrum natural antioxidant with important application prospects.