Bioaccessibility and catabolism of phenolic compounds from jaboticaba (Myrciaria trunciflora) fruit peel during in vitro gastrointestinal digestion and colonic fermentation

Jaboticaba peel powder (JPP) digestion was investigated for the first time using an in vitro static model of gastrointestinal digestion associated with a colonic fermentation assay with human feces to elucidate the catabolism and bioaccessibility of fruit polyphenols. Anthocyanins had low bioaccessibility (0.08-2.3%). Most hydrolyzable tannins (1.2-166.0%) and flavonols (0-36.8%) had greater bioaccessibility than anthocyanins. Despite their low bioaccessibility (0.08-2.3%), anthocyanins were the most abundant polyphenols in JPP and in the bioaccessible intestinal fraction followed by hydrolyzable tannins. There was fast degradation of anthocyanins and progressive catabolism of hydrolyzable tannins during the colonic fermentation assay. Urolithins and protocatechuic acid were the major catabolites found; their increase was parallel to the decrease of pathogenic bacteria counts and increase of short-chain fatty acids and gas production. JPP digestion yields bioactive polyphenol catabolites that may act as antioxidants and, with JPP dietary fiber, improve gut microbiota metabolism.