Department of Food Science and Nutrition, Center for Microbial and Plant Genomics, University of Minnesota, St. Paul, Minnesota, USA.
Appl Environ Microbiol. 2012 Feb;78(4):933-40. doi: 10.1128/AEM.05848-11. Epub 2011 Nov 18.
While ingestion of synbiotic yogurts containing Bifidobacterium animalis subsp. lactis and inulin is increasing, their effect on certain microbial groups in the human intestine is unclear. To further investigate this, a large-scale, crossover-design, placebo-controlled study was utilized to evaluate the effect of a synbiotic yogurt containing B. animalis subsp. lactis Bb-12 and inulin on the human intestinal bifidobacteria, clostridia, and enterobacteria. Fecal samples were collected at 14 time points from 46 volunteers who completed the study, and changes in the intestinal bacterial levels were monitored using real-time PCR. Strain Bb-12 could not be detected in feces after 2 weeks of washout. A live/dead PCR procedure indicated that the Bb-12 strain detected in the fecal samples was alive. A significant increase (P < 0.001) in the total bifidobacterial numbers was seen in both groups of subjects during the final washout period compared to the prefeeding period. This increase in total bifidobacteria corresponded with a significant decrease (P < 0.05) in numbers of clostridia but not enterobacteria. No significant differences in numbers of bifidobacteria, clostridia, or enterobacteria were observed between the probiotic and placebo groups during any of the feeding periods. However, subgrouping subjects based on lower initial bifidobacterial numbers or higher initial clostridial numbers did show corresponding significant differences between the synbiotic yogurt and placebo groups. This was not observed for a subgroup with higher initial enterobacterial numbers. While this synbiotic yogurt can increase bifidobacterial numbers and decrease clostridial numbers (but not enterobacterial numbers) in some individuals, it cannot modulate these microbial groups in the majority of individuals.
虽然含有乳双歧杆菌亚种。 lactis 和菊粉的合生酸奶的摄入量正在增加，但它们对人体肠道中某些微生物群的影响尚不清楚。为了进一步研究这一点，利用一项大规模、交叉设计、安慰剂对照研究来评估含有乳双歧杆菌亚种。 lactis Bb-12 和菊粉的合生酸奶对人体肠道双歧杆菌、梭菌和肠杆菌的影响。46 名完成研究的志愿者在 14 个时间点采集粪便样本，并使用实时 PCR 监测肠道细菌水平的变化。在洗脱 2 周后，粪便中无法检测到 Bb-12 菌株。活/死 PCR 程序表明，在粪便样本中检测到的 Bb-12 菌株是活的。与预喂养期相比，在最后洗脱期，两组受试者的总双歧杆菌数量均显著增加（P<0.001）。双歧杆菌总数的增加与梭菌数量的显著减少（P<0.05）相对应，但与肠杆菌数量无关。在任何喂养期，益生菌组和安慰剂组之间的双歧杆菌、梭菌或肠杆菌数量均无显著差异。然而，根据较低的初始双歧杆菌数量或较高的初始梭菌数量对受试者进行亚组分类，在合生酸奶组和安慰剂组之间确实存在相应的显著差异。对于初始肠杆菌数量较高的亚组，未观察到这种情况。虽然这种合生酸奶可以增加某些个体的双歧杆菌数量并减少梭菌数量（但不能减少肠杆菌数量），但它不能调节大多数个体的这些微生物群。
