Screening Of Lactic Acid Bacteria With Antioxidant Activity From Kimchi Homemade And Assessment Of Their Anti-obesity Functions

In recent years,the special physiological activity and beneficial functions of lactic acid bacteria(LAB)has attracted a great attention.How to screen out LAB strains with specific and excellent probiotic functions is the main problem facing the development of active LAB.In this paper,the LAB with antioxidant activities were screened out from Kimchi homemade and its anti-obesity functions was studied.The results are as follows:In this study,a sequential screening strategy was developed to efficiently isolate and obtain 65 LAB strains from Kimchi by the experiment of catalase,Gram stain and 16SrDNA using MRS medium,including 33 Enterococcus faecium,18 Lactobacillus plantarum,11 Lactobacillus brevis,2 Pediococcus ethanolidurans and 1 Lactobacillus casei.The effects of isolated strains on 2,2-diphenyl-l-picrylhydrazyl(DPPH)and hydroxy radical scavenging were studied,and 2 strains with high DPPH scavenging rate(>40%)and hydroxy radical scavenging rate(>70%)were screened out--Enterococcus faecium F11 and Lactobacillus brevis B03,which could be used to study functional evaluation as potential probiotic bacteria.The model of hyperlipidemia-rat fed with high-fat diet was intervened by 2 LAB stains with antioxidant activity,and relations between strains and the body weight of obesity rat and liver lipid peroxidation were studied emphatically.Results suggested that no anti-obesity effect was found in the high-fat induced rats and no significant improvement in the body fate index,while E.faecium F11 could decrease the hyperlipidemia to a certain extent.The total cholesterol(TC)and triglyceride(TG)contents of the L.brevis B03 and control group were higher comparing with the high-fat group.The MDA content of rat liver intervened by L.brevis B03 was higher than that of the normal group and model group,but the liver Had no significant difference compared with normal subjects.In conclusion,the research screened out 2 LAB strains with superior antioxidant activity.The results of activity test in vivo,which had great potential application value,made positive explorations for elaborating the influence of probiotic intake on physiological state and development of LAB resources.