{Reference Type}: Journal Article {Title}: Inhibition mechanism of different structural polyphenols against α-amylase studied by solid-state NMR and molecular docking. {Author}: Peng Q;Ma Y;Wang Z;Wang J; {Journal}: Int J Biol Macromol {Volume}: 275 {Issue}: 0 {Year}: 2024 Aug 8 {Factor}: 8.025 {DOI}: 10.1016/j.ijbiomac.2024.133757 {Abstract}: Polyphenol has the considerable effects for inhibition of digestive enzymes, however, inhibition mechanism of molecular size-dependent polyphenols on enzyme activity is still lacking. Herein, inhibition effect and binding interactions of three different structural polyphenols (catechol, quercetin and hesperidin) on α-amylase were studied. Inhibition assays proved that polyphenols significantly inhibited α-amylase and their effects were increased with their molecular sizes. Hesperidin showed the highest inhibition ability of α-amylase, which was determined as IC50 = 0.43 mg/mL. Fluorescence and FT-IR spectroscopy proved that inter-molecular interactions between polyphenols and α-amylase occurred through non-covalent bonds. Besides, the secondary structure of α-amylase was obviously changed after binding with polyphenols. Inter-molecular interactions were investigated using solid-state NMR and molecular docking. Findings proved that hydrogen bonds and π-π stacking interactions were the mainly inter-molecular interactions. We hope this contribution could provide a theoretical basis for developing some digestive enzyme inhibitors from natural polyphenols.