Vázquez Clotilde, Botella-Carretero José I, García-Albiach Raimundo, Pozuelo María J, Rodríguez-Baños Mercedes, Baquero Fernando, Baltadjieva María A, del Campo Rosa
Departamento de Nutrición y Obesidad, y CIBER de Fisiopatología de la Obesidad y Nutrición (CIBERobn), Hospital Universitario Ramón y Cajal y Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain.
Nutr Hosp. 2013 Jul-Aug;28(4):1227-35. doi: 10.3305/nh.2013.28.4.6540.
Genetic diversity and resistance of Lactobacillus bulgaricus sbsp. delbrueckii collection with 100 isolates from different home-made yogurt in rural Bulgarian areas were determined.
The strain K98 was the most resistant to bile salts and low pH. Survival and effects on short chain fatty acids production were tested in 20 healthy volunteers. High genetic diversity was observed in the L. bulgaricus collection by RAPD, whereas the ability of tolerate high deoxycholic acid concentrations, and different acid pHs was variable. The strain K98 was selected and used to prepare a homemade yogurt which was administered to 20 healthy volunteers (500 ml/day during 15d). A basal faecal sample and another after yogurt intake were recovered.
DGGE experiments, using both universal and Lactic Acid Bacteria (LAB) primers, demonstrated no significant changes in the qualitative composition of gut microbiota. A band corresponding to L. bulgaricus was observed in all 20 samples. Viable L. bulgaricus K98 strain was only recovered in one volunteer. After yogurt intake we found an increase of LAB and Clostridium perfringens, and a decrease of Bacteroides- Prevotella-Porphyromonas. In addition, increases of acetic, butyric and 2-hydroxy-butyric acids in faeces were detected.
Genetic diversity of L. delbrueckii subsp. bulgaricus especie is high We have isolated a probiotic resistant strain to bile and high acidity, L. delbrueckii subsp. bulgaricus-K98. Qualitative and quantitative changes in the intestinal microbiota are found after ingestion of a homemade yogurt containing this strain, with a concomitant increase in faecal SCFA. Our findings support the interest in developing further studies providing different amounts of L. delbrueckii subsp. bulgaricus-K98, and should evaluate its clinical effects in human disease.
测定保加利亚农村地区不同自制酸奶中分离出的100株德氏保加利亚乳杆菌保加利亚亚种的遗传多样性和抗性。
K98菌株对胆盐和低pH值的耐受性最强。在20名健康志愿者中测试了其存活率及对短链脂肪酸产生的影响。通过随机扩增多态性DNA（RAPD）分析发现德氏保加利亚乳杆菌群体具有较高的遗传多样性，但其耐受高浓度脱氧胆酸和不同酸性pH值的能力存在差异。选取K98菌株制作自制酸奶，并让20名健康志愿者（15天内每天摄入500毫升）食用。采集基础粪便样本以及食用酸奶后的粪便样本。
使用通用引物和乳酸菌（LAB）引物进行的变性梯度凝胶电泳（DGGE）实验表明，肠道微生物群的定性组成没有显著变化。在所有20个样本中均观察到一条与德氏保加利亚乳杆菌对应的条带。仅在一名志愿者的样本中检测到存活的德氏保加利亚乳杆菌K98菌株。食用酸奶后，我们发现乳酸菌和产气荚膜梭菌数量增加，拟杆菌-普雷沃菌-卟啉单胞菌数量减少。此外，还检测到粪便中乙酸、丁酸和2-羟基丁酸含量增加。
德氏保加利亚乳杆菌亚种的遗传多样性较高。我们分离出了一株对胆汁和高酸度具有抗性的益生菌菌株——德氏保加利亚乳杆菌-K98。摄入含有该菌株的自制酸奶后，肠道微生物群在定性和定量方面均发生了变化，同时粪便中短链脂肪酸含量增加。我们的研究结果支持开展进一步研究，提供不同剂量的德氏保加利亚乳杆菌-K98，并评估其对人类疾病的临床疗效。
