Screening, characterization of trace a-glucosidase inhibitors from the root of Pueraria lobata and evaluation of their hypoglycemic activity

Pueraria lobata (Willd.) Ohwi (Gegen) is a nutritious medicine food homology plant that has been recorded in many ancient remedies for diabetes. However, its hypoglycemic active components and related mechanisms have not been fully elucidated. In this study, potential alpha-glucosidase inhibitors in Pueraria lobata were investigated by liquid-liquid refined extraction, high-resolution profiling and their hypoglycemic activity were evaluated. Ten compounds showing alpha-glucosidase inhibitory bioactivity were separated and identified, including two new compounds, 8-geranyl-7, 3', 4' -trihydroxy-isoflavone (4) and 8-geranyl-7, 2', 4'-trihydroxy-isoflavone (6), and eight known compounds. All screened compounds showed potential hypoglycemic activity, in which compounds 4, 6, 7, 8, 9 and 10 showed strong inhibitory activity (IC50 < 8 mu M). Furthermore, molecular docking simulation revealed binding energy and interacting amino acid residues of the screened compounds with alpha-glucosidase, strongly supporting their potential as alpha-glucosidase inhibitors.

Automated summary

In this study, potential alpha-glucosidase inhibitors were identified in Pueraria lobata. Ten compounds, including two new compounds, were found to inhibit alpha-glucosidase activity. These compounds showed strong hypoglycemic activity and their potential as alpha-glucosidase inhibitors was supported by molecular docking simulation.