Study on the scavenging ability of lactic acid bacteria on free radicals

The scavenging ability of 52 strains on DPPH free radicals were introduced in this paper and screened out 3 strains which have higher scavenging ability on DPPH radicals,and studied about their scavenging abilities on superoxide anion radicals,hydroxyl radicals and reducing activity.According to the data,the cell-free extracts of ZS-2 showed the highest ability to scavenge DPPH free radicals(46.53%) and higher scavenging ability on hydroxyl radicals.The intact cell and cell-free extracts of ZS-2 on superoxide anion radicals were not detected.The intact cell of FS-3 and BCX-9 on hydroxyl radicals showed higher scavenging effect than the cell-free extracts and better scavenging ability on superoxide anion.The cell-free extracts of FS-3 showed the highest scavenging effect on superoxide anion radicals.Three strains showed the reducing activity.The study demonstrated that the intact cell and the cell-free extracts of lactic acid bacteria have different scavenging ability in vitro.