新疆喀什地区维吾尔族母乳源双歧杆菌分离筛选及其益生特性分析

采用多重聚合酶链式反应指纹图谱结合16S rRNA基因测序技术对新疆喀什地区维吾尔族母乳分离的双歧杆菌进行鉴定和遗传差异分析，并检测常规生理生化和糖代谢表型特征，同时测试菌株对6 种常见病原菌和3 种母乳源条件致病菌的抑菌性能和对胃肠液的耐受性。结果显示，15 份母乳样品中共分离15 株双歧杆菌，测序结果将菌株归属于3 个种以及2 个亚种，包括8 株假小链双歧杆菌（Bifidobacterium pseudocatenulatum）、2 株短双歧杆菌（B. breve）、2 株长双歧杆菌长亚种（B. longum subsp. longum）和3 株长双歧杆菌婴儿亚种（B. longum subsp. infantis）。抑菌实验表明，15 株测试菌株中，隶属于B. pseudocatenulatum的4 株菌MY92、MY75-1、MY72、MY81的抑菌谱更广，抑菌能力更强；胃肠液耐受性实验表明菌株MY92无论在模拟胃液还是模拟肠液中存活率均最高，分别达到20.37%和0.302%。基于以上描述特性，MY92作为一株有效的益生菌株，具有潜在的利用价值，为后期进一步作为防止婴幼儿腹泻辅助制剂的开发提供参考。

Isolation,Screening and Probiotic Characteristics Analysis of Bifidobacterium from Breast Milk of Uygur Women in Kashi,Xinjiang

In this study, bifidobacterial strains isolated from the breast milk of Uygur women in Kashi, Xinjiang were identified at the species level and then their genetic variations were analyzed by using a combination of repetitive polymerase chain reaction (rep-PCR) fingerprinting and sequence analysis of the 16S rRNA gene. Meanwhile, routine physiological and biochemical parameters and phenotypic characteristics of sugar metabolism were examined, and the antibacterial activity of these isolates against 6 common pathogens and 3 conditional pathogens from breast milk was investigated along with their gastrointestinal tolerance. Our results showed that a total of 15 bifidobacterial strains including Bifidobacterium pseudocatenulatum (8 strains), B. breve (2 strains), B. longum subsp. longum (2 strains) and B. longum subsp. infantis (3 strains) were isolated from 15 breast milk samples. Among these strains, four B. pseudocatenulatum stains, namely MY92, MY75-1, MY72 and MY81, had a more potent and?broader-spectrum antibacterial activity, and strain MY92 showed the highest survival rate (20.37% and 0.302%) after challenge with simulated gastric and intestinal juices. Based on the above data, B. pseudocatenulatum MY92 is promising for application as a potent probiotic strain and shows great potential for the development of adjuvant preparations for preventing diarrhea in infants and young children.