内蒙古发酵酸乳制品中乳酸菌的分离鉴定

Isolation and Identification of Lactic Acid Bacteria in Fermented Yogurt Products in Inner Mongolia

以采集自内蒙古锡林郭勒盟正蓝旗的2份发酵酸乳样品为研究对象,采用传统纯化培养技术、16S rDNA基因序列测定并构建系统发育树的方法,对样品中的乳酸菌进行了分离鉴定,以期解析发酵乳中乳酸菌的多样性,积累食品微生物资源。研究结果显示,共分离15株乳酸菌,被鉴定为3个属9个种,3个属分别为乳酸乳球菌属、明串珠菌属和乳杆菌属,9个种分别为乳酸乳球菌叶蝉亚种(Lactococcus lactis subsp. hordniae,3株)、乳酸乳球菌(Lactococcus lactis,1株)、乳酸乳球菌乳脂亚种(Lactococcus lactis subsp. cremoris,1株)、乳明串珠菌(Leuconostoc lactis,3株)、肠膜明串珠菌肠膜亚种(Leuconostoc mesenteroides subsp. mesenteroides,1株)、肠膜明串珠菌右旋葡聚糖亚种(Leuconostoc mesenteroides subsp. dextranicum,1株)、植物乳杆菌(Lactobacillus plantarum,1株)、副干酪乳杆菌(Lactobacillus paracasei,3株)和干酪乳杆菌(Lactobacillus casei,1株)。综上表明,该研究采集的酸乳样品中乳酸菌资源丰富,是内蒙古传统乳制品优良发酵剂的研发和产业化生产的潜在微生物资源。

The objectives of this study were to reveal the diversity of lactic acid bacteria in the traditional fermented yogurts,and to accumulate food microbial resources.Two fermented yogurt samples were collected from Zhenglan Banner of Xilin Gol League of Inner Mongolia.The lactic acid bacteria in the samples were isolated with traditional purification and culture techniques,and were subsequently identified using 16S rDNA gene PCR and sequencing in combination with the construction of phylogenetic tree.The results showed that a total of 15 strains of lactic acid bacteria were isolated and identified as 9 species belonging to 3 genera.The 3 identified genera were Lactococcus,Leuconostoc and Lactobacillus,and the 9 observed species were Lactococcus lactis subsp.hordniae(n=3),Lactococcus lactis(n=1),Lactococcus lactis subsp.cremoris(n=1),Leuconostoc lactis(n=3),Leuconostoc mesenteroides subsp.mesenteroides(n=1),Leuconostoc mesenteroides subsp.dextranicum(n=1),Lactobacillus plantarum(n=1),Lactobacillus paracasei(n=3),and Lactobacillus casei(n=1).In summary,the collected yogurt samples are rich in lactic acid bacteria resources,and are potential microbial resources for the research,development and industrial production of excellent fermenting agents for traditional dairy products in Inner Mongolia.