Fermented dairy and intestinal microbiota

BackgroundFermented foods consumption has gained much attention due to the ability to deliver live microbes and fermentation metabolites to the gut, which might play a role in health-promotion or disease prevention. It was the overall goal of this study to determine the impact of long-term daily consumption of a high-protein drained yoghurt (Skyr) containing mainly Streptococcus thermophilus, lactose and lactate, on intestinal microbial ecology and the fermentation metabolome. ResultsWhile overall microbiota composition based on ß-diversity was not substantially altered, quantitative microbiome profiling indicated reduced abundance of the fibre utilizing Bacteroides and Roseburia in the Skyr group, while fecal lactate levels and abundance of functionally different lactate utilizer including Anaerobutyricum hallii and Desulfovibrionaceae were increased. Skyr consumption led to individually higher fecal succinate levels, and a concurrent decrease in abundance of the succinate-producing Barnesiella and Alistipes, and of propionate-producing succinate utilizers Alistipes and Phascolarcobacterium. Fecal concentrations of total SCFA, acetate and propionate where lower in the Skyr group, while the proportion of butyrate was significantly increased. ConclusionTaken together, regular consumption of a high-protein, drained yogurt led to persistent changes in abundance of selected functional microbial groups, and in levels and profiles of fermentation metabolite indicating a strong response in microbial activity. Our results suggest that Skyr impacted intestinal microbial cross-feeding activities likely due to the nutritive and microbial components.