Interactions between phenolic compounds, amylolytic enzymes and starch: an updated overview

Polyphenols are reported to modulate starch digestibility via either direct inhibition of alpha-glycosidase digestive enzymes and/or the formation of inclusion and non-inclusion complexes with starch. In particular, the former process results from binding interactions between phenolics and the free enzymes. Concerning the latter process, recent evidences support specific non-covalent bonds between different polyphenols (mainly flavonoids, phenolic acids and tannins) and carbohydrate polymers via hydrogen bonds and hydrophobic interactions. This role played by phenolics towards starch digestibility could represent a valid strategy to design functional foods and/or to manage type II diabetes. This short-review provides an updated and critical overview on the complex interactions occurring between phenolic compounds and amylolytic enzymes within the food-matrix and during food digestion, together with the postulated effects provided by polyphenols-starch interactions on starch digestibility. Noteworthy, considering that the most recent works on this topic are from in vitro studies, further in vivo research is deserved.