Chotelersak Kruawan, Thamacharoensuk Tanatip, Tanasupawat Somboon, Nantavisai Kwannan, Taweechotipatr Malai, Puttikamonkul Srisombat
J Med Assoc Thai. 2016 Nov;99 Suppl 8:S90-S98.
The microbiota of human plays an important role in the health improvement, and found abundant in the gastrointestinal tract. In recent years, probiotics have been increasingly used in prevention of certain intestinal diseases. The most important population to study the microbiome is probably in the healthy newborns.
The preliminary study aimed to isolate and identify the gut microbiota of newborns for the assessment of prevalent Lactic Acid Bacteria (LAB) distribution.
Thirty eight Thai newborns, 0-5 days old of both sexes were subjected for fecal samples collection. Isolated bacteria were cultivated on the MRS selective media and further phenotypically characterized by conventional methods including Gram stain, catalase, and lactic acid production. Genotypic identification was completed by 16S rRNA gene sequencing and phylogenetic analysis.
Forty five isolates of LAB and non-LAB bacteria were obtained from feces of newborns. The most prevalence LAB found in this population were 45% Enterococcus faecalis, 14% E. faecium, 11% E. hirae, 11% Lactobacillus paracasei, and 2% L. gasseri. Unusually, Gram-negative bacteria including Klebsiella pneumoniae, Enterobacter hormaechei, Escherichia fergusonii, Leclercia adecarboxylata, and Shigella flexneri were isolated among LAB strains on the selective MRS media.
The gut microbiota was a great resource of beneficial LAB which was remarkably distributed among this population of Thai newborns. Further study on individual LAB isolates for the effective probiotics development would be essentially investigated for future alternative treatment of gastrointestinal diseases.
人类微生物群在促进健康方面发挥着重要作用,且在胃肠道中大量存在。近年来,益生菌越来越多地用于预防某些肠道疾病。研究微生物组最重要的群体可能是健康的新生儿。
本初步研究旨在分离和鉴定新生儿的肠道微生物群,以评估常见乳酸菌(LAB)的分布情况。
收集38名0至5日龄泰国新生儿的粪便样本。将分离出的细菌接种于MRS选择性培养基上,并通过常规方法进行表型鉴定,包括革兰氏染色、过氧化氢酶检测和乳酸生成检测。通过16S rRNA基因测序和系统发育分析完成基因型鉴定。
从新生儿粪便中获得了45株LAB和非LAB细菌。该群体中最常见的LAB为45%粪肠球菌、14%屎肠球菌、11%海氏肠球菌、11%副干酪乳杆菌和2%加氏乳杆菌。异常的是,在选择性MRS培养基上的LAB菌株中分离出了革兰氏阴性菌,包括肺炎克雷伯菌、霍氏肠杆菌、弗格森埃希菌、解羧勒克菌和福氏志贺菌。
肠道微生物群是有益LAB的重要来源,在泰国新生儿群体中分布显著。为开发有效的益生菌,对单个LAB分离株进行进一步研究对于未来胃肠道疾病的替代治疗至关重要。