A comparison of several in vitro evaluation methods of lactobacillus cell- free extract antioxidant activity

The antioxidant activity of lactic acid bacteria and their role in promoting human health are closely related.In this study,3 classic chemical antioxidant capacity evaluation indicators in vitro such as DPPH radical scavenging activity,hydroxyl radical scavenging activity and reduction activity were engaged to evaluate the antioxidant capacity of cell- free extract of 17 lactic acid bacteria from different sources. The results showed the presence of interspecific and intraspecific differences among the cell- free extract antioxidant activity of lactic acid bacteria from different sources.Significant correlation was found among the results got with 3 chemical evaluation indicators.All 3 chemical evaluation showed Lactobacillus acidophilus CCFM 8 had the highest antioxidant activity,while L.fermentum CCFM381 had the weakest antioxidant activity.Further evaluation results of antioxidase activity of lactobacillus cell- free extract showed perfect consistency with that got with comprehensive evaluation of 3chemical evaluation indicators.This study provided a reliable reference for comprehensive evaluation of the antioxidation ability of lactic acid bacteria and in vitro screening of lactic acid bacteria with high antioxidant activity.