Background: Bauhinia winitii (BW) (Fabaceae) plant revealed poor phytochemical investigation and anti-diabetic report. As one of the Bauhinia family which known with abundant flavonoids content, contrary, BW was only used for the treatment of diarrhea in Thai conservative remedy. Objectives: The aim of this study was to investigate the phytochemical constituents and anti-alpha glucosidase activity of BW. Materials and Methods: Phytochemical study was based on the alpha-glucosidase inhibitory effect. Isolated compounds were determined by chromatographic and spectroscopic techniques. The alpha-glucosidase enzymatic inhibitory test was then connected with molecular docking affirmation. Results: The ethyl acetate and ethanol extracts from leaves and woods exhibited the strongest activity with above 60% inhibition. Six compounds were isolated from these extracts, naringenin (1), luteolin (2), isoquercitrin (3), griffonilide (4), lithospermoside (5), and epi-β amyrin (6). The alpha-glucosidase inhibitory test showed that flavonoids performed potential results with naringenin as the highest IC50 on 0.41 mM. The docking ensured the flavonoids activated at the same binding of alpha-glucosidase enzyme active site. Conclusion: This study would be the first report of chemical constituents from BW with its isolated compounds was presented anti-diabetic activity as alpha-glucosidase inhibitors.
Keywords: Alpha-glucosidase inhibitor, anti-diabetes, Bauhinia winitii, molecular docking, phytochemical investigation