降胆固醇乳酸菌的筛选、鉴定及生长特性  

Study on characteristics of growth,screening and identification of cholesterol-reducing Lactic acid bacteria

作　　者：居华[1] 刘书亮[1] 敖灵[1] 王燚[1] 

机构地区：[1]四川农业大学食品科学系,四川雅安625014

出　　处：《中国乳品工业》2007年第8期7-10,22,共5页China Dairy Industry

基　　金：四川省教育厅项目(005208)

摘　　要：从香肠、腊肉、泡菜、酸奶等传统发酵食品中获得的42株乳酸菌,应用不同胆固醇源的高胆固醇MRS-broth测定其降胆固醇能力,从中筛选出降胆固醇能力较高的6株菌,分别为CM7,S9,P5,P9,Y1,P215菌株。其中P215菌株具有较好的耐酸性、一定的胆盐耐受力和较高胆固醇降解率。结合形态学、生理生化特性和16S rDNA序列同源性分析,P215菌株被鉴定为植物乳杆菌(Lactobacillus plan-tarum)。并研究了P215菌株在添加鸡蛋黄和化合物胆固醇的MRS-broth中的生长曲线、pH值变化及胆固醇降解率。结果表明,P215菌株在高胆固醇MRS中2 h后进入对数生长期,10 h后进入稳定期,22 h后逐渐进入衰退期。The cholesterol-reducing ability was tested on 42 strains of bacteria isolated from traditional fermented food such as sausage, cured meat, pickle and yogurt using cholesterol-enriched MRS medium including different cholesterol sources, six strains （CM7, S8 ,P5 ,P9,Y1, P215）were screened for their excellent cholesterol-reducing ability . P215 turned out to be better acid resistance, bile salt tolerance and the best cholesterol-reducing ability.P215 was identified as Lactobacillus plantamm with morphologic observe, biochemical identification and sequence analyse of 16S rDNA . In addition, its acid product and growth curve were measured using MRS-broth added yolk and standard cholesterol. It is proved that P215 enters the period of logarithm growth after 2h in high cholesterol MRS-broth （ its pH value descends quickly, ability of cholesterol-reducing increases, and live fungus ascends exponentially）,the period of stabilization after 10h （its pH value level off gradually, ability of cholesterol-reducing increases slowly, and live fungus gets the top） and the period of decline （its pH value keeps stabilization, ability of cholesterol-reducing get 58% and 48%,and live fungus die gradually ）.

关 键 词：降胆固醇 乳酸菌 植物乳杆菌 体外筛选 鉴定 

分 类 号：Q93-331[生物学—微生物学] Q935