Study on the Antioxidation and Hypolipidemic Effects of Lactic Acid Bacteria

Probiotic lactic acid bacteria with a variety of physiological functions, and its antioxidant activity and lipid-lowering function more and more attention . In this study, milk , tomatoes and sauerkraut isolated 52 strains of lactic acid bacteria as the research object , its cluster analysis using random amplified polymorphic DNA fingerprinting technique (RAPD) , two screened in vitro antioxidant capacity better lactic acid bacteria N2 and X9, 16S rDNA technology and physiological and biochemical tests to identify these two lactic acid bacteria . Further using The N2 and X9 mice pilot study evaluated the antioxidant effect and body lipid levels . In vitro antioxidant test results show that the antioxidant capacity of 32 lactic acid bacteria , N2 and X9 antioxidant capacity is relatively good . Lactic acid bacteria supernatant fermentation broth superoxide radical scavenging range is 3.19 to 25.24% ; hydroxyl radical scavenging range is 11.00 to 83.58% ; suppression of anti- lipid peroxidation range is 0.39 to 53.70% . By 16S rDNA sequence analysis and physiological and biochemical tests, strain N2 and X9 have been identified as Lactobacillus casei (L.casei) and Lactobacillus plantarum (L.plantarum). The mice test results show that the enhanced antioxidant activity , the two strains can improve the groups tested mice in the liver and kidney tissue superoxide dismutase (SOD) and glutathione peroxidase enzyme (GSH-px) activity reduces malondialdehyde (MDA) content , but does not significantly impact the vitality of catalase (CAT) ; lowering blood lipid levels , two bacteria can reduce hyperlipidemia mice total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-c), and the effect of lactic acid bacteria X9 superior N2 . Further study found that lactic acid bacteria N2 and X9 allows each group of mice peripheral blood CD4 T lymphocyte subsets risen CD4 / CD8 ratio improved immunity . A measurement result of the mouse liver antioxidant gene expression of Nrf2 protein showed that this two lactic acid bacteria are able to activate Nrf2 and abundantly expressed to resist oxidative damage .