Probiotics supplementation to ileostoma bacterial community cause dynamic increase in their resistance to perturbations and metabolic utilization

The gut microbiota plays a pivotal role in health and disease. The use of probiotics as microbiota targeted therapies is a promising strategy to improve host health. However, dynamic molecular mechanisms are often not elucidated, especially when targeting the small intestinal microbiota. Here we show that supplementation of a probiotic formula (Ecologic825) to the small intestinal bacterial community counteracts the growth of Enterococcaceae, Bacteroidetes and Enterobacteriaceae and reduces ethanol production, leading to major changes in primary metabolism and dynamic resistance to perturbations. The observed alterations were the result of an initial decrease in pH due to increased lactate production by the probiotics, followed by a sharp increase in the levels of butyrate and propionate. As a consequence, probiotics supplementation increased the resistance to perturbation and increased nutrient utilization. Overall, this study shows how probiotic supplementation can affect the small intestinal microbiota and how network theory can be used for the improvement of current and development of novel probiotic therapies.