Modulation and metabolism of obesity-associated microbiota in a dynamic simulator of the human gut microbiota

The in vitro development of representative gut microbiota from obese individuals has been approached in the present study by using a three-stage dynamic simulator of the human gut microbiota (BFBL Gut Model). During the stabilization period, aimed to reach the microbiota steady state, initial differences found between normal-weight (Nw) and obese (Ob) faecal samples were reproduced. The differentiation included lower values of Akkermansia, Enterococcus and Faecalibacterium and higher values of Lactobacillus for the Ob microbiota when compared with the Nw microbiota. The change of food ingredients to simulate a high consumption of readily-fermented carbohydrates and fructose-enriched beverages maintained these differences and additionally produced a decrease of Bifidobacterium in the Ob microbiota. Related to obesity metabolic signatures, a lower capacity to produce propionate was characteristic of the Ob microbiota under all the tested conditions. This could be useful in the selection of food ingredients for targeted production of propionate by the human gut microbiota prior to their assessment in nutritional intervention studies related to obesity.