Sitosterol and stigmasterol have been reported to have very low α-glucosidase inhibitory activities (Atta-ur-Rahman et al.,2008;Kumar et al.,2013). Apigenin has also been identified as a weak α-glucosidase inhibitor due to its structure, which contains only one hydroxyl substitution on the B-ring and no substitution at the 3-position (Tadera et al.,2006). According to a comparative study on several phenolic compounds by Kwon et al.(2008), caffeic acid is a potent α-glucosidase inhibitor.Thus,the pronounced α-glucosidase inhibitory activity of the hexane extract of Murdannia bracteata might be ascribed to the presence of this compound.