α-Glucosidase inhibition by flavonoids: an <i>in vitro</i> and <i>in silico</i> structure–activity relationship study

<p>α-Glucosidase inhibitors are described as the most effective in reducing post-prandial hyperglycaemia (PPHG) from all available anti-diabetic drugs used in the management of type 2 diabetes <i>mellitus</i>. As flavonoids are promising modulators of this enzyme’s activity, a panel of 44 flavonoids, organised in five groups, was screened for their inhibitory activity of α-glucosidase, based on <i>in vitro</i> structure–activity relationship studies. Inhibitory kinetic analysis and molecular docking calculations were also applied for selected compounds. A flavonoid with two catechol groups in A- and B-rings, together with a 3-OH group at C-ring, was the most active, presenting an IC<sub>50</sub> much lower than the one found for the most widely prescribed α-glucosidase inhibitor, <b>acarbose</b>. The present work suggests that several of the studied flavonoids have the potential to be used as alternatives for the regulation of PPHG.</p>