김치에서 분리된 콜레스테롤 감소능을 가진 유산균의 특성

Abstract

The objective of this study was to evaluate the functional Lactic acid bacteria (LAB) exhibiting cholesterol-lowering activity in Korean traditional fermented food. LAB, very significant bacteria in the microbial world have been used to ferment or culture foods for at least 4,000 years and known to promote good health and have high economic value. Thus for this study, we isolated LAB strains from Kimchi and the cholesterol-lowering effect evaluated in the presence of 0.1% cholesterol by determining the difference in cholesterol content in the medium before and after incubating each LAB strains. All LAB strains tested in this study were able to assimilate cholesterol at varying levels ranging from 35.0% to 99.4%. Among them, the candidate LAB 16 strain exhibited the highest cholesterol-lowering effect with 99.4% cholesterol assimilation. Also in order to assess the potential probiotic use of LAB strains, we further performed the acid tolerance, bile tolerance and salt tolerance test. The LAB 16 strain exhibited potent stability against acid, bile and salt stress. In addition, the antioxidant effect of LAB strains were investigated based on the analyses of 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical scavenging assay, 2-azinobis(3-ethylbenzthiazoline)-6-sulfonic acid(ABTS) radical scavenging assay and oxygen radical absorbance capacity(ORAC) assay. All LAB strains possessed strong antioxidant ability against all the radicals tested. Also, All LAB strains did not show α-haemolysis or β-haemolysis on blood agar. We can therefore conclude that we have successful isolated a candidate LAB strain for potential probiotic use which exhibits a strong cholesterol-lowering effect and has an antioxidant capability.