The effects of açaí (Euterpe oleracea) intake on gut bacteria and their metabolites in obese mice

The consumption of unsaturated fatty acids, dietary fiber, and anthocyanins, mainly found in fruits, are associated with better health status and modulation of gut microbiota. Thus, the aim of this study is the effect of consumption of Brazilian açaí pulp on metabolic disorders associated with obesity and its prebiotic capacity on gut microbiota. Twenty-four male mice were fed with normolipidic and high-fat standard diets, and normolipidic and a high-fat diets with 2 % of açaí pulp for 13 weeks. The proximal composition, bioactive compounds, and fatty acids composition of açai pulp was evaluated. For metabolic analysis body composition (whole and adipose weight), glucose metabolism (glucose and insulin tolerance tests), lipids excretion (cholesterol fecal content), and gut microbiota and metabolites (composition and short-chain fatty acids- SCFA) were assessed and compared statistically. The açaí is a fruit source of monounsaturated acids, fibers and anthocyanin with high antioxidant power. Its intake increased weight gain and adipose tissue (except mesenteric adipose tissue) and did not impact on glucose metabolism. Açaí intake increased cholesterol fecal excretion associated with a balanced diet, and increased SCFA production in both diet types, indicating that a it might favor the modulation of certain gut bacteria phylum and genera responsible for the SCFA production, such as Actinobacteria , Patescibacteria , Firmicutes , and Akkermansia , Faecalibaculum , Bifidobacteria , Lactobacilli . The 2 % açaí intake was not able to modulated positively the metabolic disorders and gut microbiota in the observed conditions. • Freeze-dried açaí pulp is a source of bioactives compounds • Açaí pulp's lipids are mostly composed by mono unsaturated fatty acids • The high fat diets favored obesogenic gut bacteria • The açaí complementation increased short-chain fatty acids production