4 种乳酸菌体外抗氧化能力的比较研究

通过抗脂质过氧化、清除DPPH自由基、清除超氧阴离子自由基(O2－ ·)、还原力、清除羟自由基实验对发酵乳杆菌、乳酸乳球菌、嗜酸乳杆菌和瑞士乳杆菌4种乳酸菌发酵上清液和胞内提取物的抗氧化能力进行研究。结果表明：4种乳酸菌的具有不同的抗氧化能力，其中瑞士乳杆菌的羟自由基清除能力、DPPH自由基清除能力和还原能力相对较高，乳酸乳球菌和嗜酸乳杆菌清除O2－ ·能力相对较强，发酵乳杆菌抗脂质过氧化能力为最强。实验还初步研究乳酸菌的抗氧化机理，显示乳酸菌存在SOD和GSH-Px，这可能与乳酸菌的抗氧化作用有一定相关性。

Comparative Antioxidant Activity of Four Species of Lactic Acid Bacteria in vitro

In this study, the antioxidant activity of the fermentation supernatants and intracellular extracts of four species of lactic acid bacteria including Lactobacillus fermentium, Lactococcus lactis, Lactobacillus acidophilus and Lactobacillus helveticus was comparatively studied by anti-lipid peroxidation assay, reducing power assay, and DPPH and superoxide anion and hydroxyl free radical scavenging assays. The results indicated that different lactic acid bacteria had different antioxidant activity. Lactobacillus helveticus had higher hydroxyl radical scavenging activity, DPPH radical scavenging activity and reducing power, while Lactococcus lactis and Lactobacillus acidophilus had notable superoxide anion radical scavenging activity. In addition, Lactobacillus fermentium had the highest lipid peroxidation-inhibitory activity. Further, the antioxidant mechanism of lactic acid bacteria may be related to the presence of SOD and GSH-Px activities.