耐酸耐胆盐乳酸菌的鉴定及筛选  

Identification and Selection of Lactic Acid Bacteria Resistant to Acid and Bile Salt

作　　者：李利[1] 孔丽[2] 张宁[2] 赵伟超[2] 肖亦农[1] 李炳学[1] 韩晓日[1] 

机构地区：[1]沈阳农业大学土地与环境学院,土肥资源高效利用国家工程实验室,辽宁沈阳110866 [2]沈阳农业大学生物科学技术学院,辽宁沈阳110866

出　　处：《食品科学》2015年第21期123-128,共6页Food Science

基　　金：国家自然科学基金面上项目(31271818);沈阳市科技创新农业科技攻关专项(F13-143-3-00);中国博士后科学基金项目(2012M510836;2013T60299)

摘　　要：从自然发酵的酸奶中分离出2株细菌,经16S rDNA分子鉴定为Lactobacillus plantarum SN1和Lactobacillus rhamnosus SN6,并对其生长曲线、产酸速率、耐酸耐胆盐能力进行了研究。L.plantarum SN1和L.rhamnosus SN6在2 h后进入对数期,16 h后达到稳定期,其OD_(600nm)值分别为8.47、7.43。L plantarum SN1和L.rhamnosus SN6的产酸速率较快,pH值在8 h后就降到了4.2以下,48 h后降到3.3左右。L.plantarum SN1和L.rhamnosus SN6在pH 4的培养基培养16 h后,其相对OD_(600nm)值分别为49.29%、47.14%,具有较强的耐酸能力。L.plantarum SN1和L.rhamnosus SN6在0.3 g/L胆盐质量浓度下培养16 h后,相对OD_(600nm)值分别为57.7%、69.48%;在0.6 g/L胆盐质量浓度下的相对OD_(600nm)值分别为48.22%、29.56%,具有较强的耐胆盐能力。结果表明:L.plantarum SN1和L rhamnosus SN6是生长性能好、产酸能力强、耐酸耐胆盐的益生菌株。Two strains of lactic acid bacteria were isolated from naturally fermented yogurt.The 16 S rDNA sequence analysis indicated that the two strains were Lactobacillus plantarum SN1 and Lactobacillus rhamnosus SN6.These strains were studied for growth curve,acid production rate,acid and bile salt tolerance.Both of them reached a logarithmic growth phase after 2 h and a stable period after 16 h with OD_（600nm） values of 8.47 and 7.43,respectively.The pH value dropped to 4.2 at 8 h and 3.3at 48 h.L.plantarum SN1 and L.rhamnosus SN6 had strong resistance to acid,and the relative OD_（600nm） value was 49.29%and 47.14%at pH 4.0 after 16 h of culture,respectively.After being cultured for 16 h at a bile salt concentration of 0.3 g/L,the relative OD_（600nm） values of L.plantarum SN1 and L.rhamnosus SN6 were 57.7% and 69.48%,respectively,compared to 48.22% and 29.56% when the concentration of bile salt was 0.6 g/L.These results show that both L.plantarum SN1 and L.rhamnosus SN6 are probiotic strains with strong growth performance,acid production and tolerance to acid and bile salt.

关 键 词：乳酸菌 耐酸耐胆盐 16S RDNA序列分析 

分 类 号：Q935[生物学—微生物学]