Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education of China, Inner Mongolia Agricultural University, Hohhot, 010018, China; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs of China, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Inner Mongolia Agricultural University, Hohhot, 010018, China.
Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education of China, Inner Mongolia Agricultural University, Hohhot, 010018, China; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs of China, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Inner Mongolia Agricultural University, Hohhot, 010018, China.
J Dairy Sci. 2020 May;103(5):4013-4025. doi: 10.3168/jds.2019-17602. Epub 2020 Feb 26.
Breast milk is the main source of nutrition for infants; it contains considerable microflora that can be transmitted to the infant endogenously or by breastfeeding, and it plays an important role in the maturation and development of the immune system. In this study, we isolated and identified lactic acid bacteria (LAB) from human colostrum, and screened 2 strains with probiotic potential. The LAB isolated from 40 human colostrum samples belonged to 5 genera: Lactobacillus, Bifidobacterium, Streptococcus, Enterococcus, and Staphylococcus. We also isolated Propionibacterium and Actinomyces. We identified a total of 197 strains of LAB derived from human colostrum based on their morphology and 16S rRNA sequence, among them 8 strains of Bifidobacterium and 10 strains of Lactobacillus, including 3 Bifidobacterium species and 4 Lactobacillus species. The physiological and biochemical characteristics of strains with good probiotic characteristics were evaluated. The tolerances of some of the Bifidobacterium and Lactobacillus strains to gastrointestinal fluid and bile salts were evaluated in vitro, using the probiotic strains Bifidobacterium lactis BB12 and Lactobacillus rhamnosus GG as controls. Among them, B. lactis Probio-M8 and L. rhamnosus Probio-M9 showed survival rates of 97.25 and 78.33% after digestion for 11 h in artificial gastrointestinal juice, and they exhibited growth delays of 0.95 and 1.87 h, respectively, in 0.3% bile salts. These two strains have the potential for application as probiotics and will facilitate functional studies of probiotics in breast milk and the development of human milk-derived probiotics.
母乳是婴儿的主要营养来源；它含有相当数量的微生物群，可以通过母乳喂养或内源性传递给婴儿，并在免疫系统的成熟和发育中发挥重要作用。在这项研究中，我们从人初乳中分离和鉴定了乳酸菌（LAB），并筛选出了 2 株具有益生菌潜力的菌株。从 40 个人初乳样本中分离出的 LAB 属于 5 个属：乳杆菌属、双歧杆菌属、链球菌属、肠球菌属和葡萄球菌属。我们还分离出丙酸杆菌属和放线菌属。我们基于形态学和 16S rRNA 序列从人初乳中鉴定出了总共 197 株 LAB，其中包括 8 株双歧杆菌和 10 株乳杆菌，包括 3 种双歧杆菌和 4 种乳杆菌。评估了具有良好益生菌特性的菌株的生理生化特性。在体外，使用益生菌菌株双歧杆菌 BB12 和鼠李糖乳杆菌 GG 作为对照，评估了一些双歧杆菌和乳杆菌菌株对胃肠道液和胆盐的耐受性。其中，B. lactis Probio-M8 和 L. rhamnosus Probio-M9 在人工胃肠液中消化 11 小时后存活率分别为 97.25%和 78.33%，在 0.3%胆盐中生长延迟分别为 0.95 和 1.87 小时。这两个菌株具有作为益生菌应用的潜力，将有助于研究母乳中益生菌的功能和开发人乳来源的益生菌。
