In vitro gastrointestinal digestion and probiotics fermentation impact on bioaccessbility of phenolics compounds and antioxidant capacity of some native and exotic fruit residues with potential antidiabetic effects

A bioaccessibility study on polyphenols, flavonoids and antioxidant capacity after the in vitro simulated digestion was evaluated for extract of fruit (caja-umbu, cashew apple, canafistula, cupuassu, soursop, manguba and strawberry) residues. The results show that ORAC assay presented a significant increase (p <= 0.05) in bioaccessibility varying from 35.99 +/- 0.02% (caja-umbu residue) to 339.83 +/- 0.06% (cupuassu residue) after the digestion process. Approximately 15.01 +/- 1.54 to 237.77 +/- 4.10% of phenolic compounds were bioaccessible after probiotics fermentation. The identification and quantification of phenolic compounds were performed through the UHPLC-QDa-MS system. Catechin and epicatechin were widely detected in all fruit residues. After the gastrointestinal digestion and probiotics fermentation the contents of simple phenolics and hydroxybenzoic acids increased. Also, the alpha-amylase inhibitory activity exhibited a maximum value of 98.66 +/- 1.41% for soursop residue. To the best of our knowledge, for the first time, bioaccessibility study on caja-umbu, canafistula and manguba residues was performed in association with antidiabetic effects. The soursop residue presented the highest bioaccessibility and can be potentially explored for application in functional foods and pharmaceuticals. Therefore, the joint consumption of probiotics and phytochemicals are essential for the effective assimilation by the human organism.