Young apple polyphenols as natural α-glucosidase inhibitors. - GreenMedInfo Summary
Young apple polyphenols as naturalα-glucosidase inhibitors: In vitro and in silico studies.
Bioorg Chem. 2020 Jan 28 ;96:103625. Epub 2020 Jan 28. PMID: 32028059
In this study, the inhibitory activity of young apple polyphenols (YAP) onα-glucosidase was investigated. Composition and inhibition analyses suggested that tannic acid (TA), (-)-epicatechin (EC) and phlorizin (PH) were the main active constituents in YAP showing α-glucosidase inhibition. PH was a competitive inhibitor, while YAP, TA and EC were the mixed-type ones. YAP, TA, PH and EC quenched the fluorescence spectrum of α-glucosidase significantly. Interestingly, the constants that indicate binding interaction between α-glucosidase and TA, PH, EC, including reciprocal of competitive inhibition constant (1/K), fluorescence quenching constant (K) and binding energy (E), were shown similar orders as TA > PH > EC, contrary to ICvalues. This indicates that binding interactions between polyphenols andα-glucosidase caused the enzyme inhibition. Additionally, potential enzyme unfolding by polyphenols interactions indicated by red-shift of maximum emission wavelength is supported by the decrease in α-helix and β-sheet contents of the enzyme. Conclusively, the α-glucosidase inhibition indicatesthat YAP may have potentials in alleviation of type 2 diabetes symptom.