Assessing enzymatic inhibitory effects of essential oil from Distichochlamys orlowii K. Larsen & MF Newman rhizomes

Distichochlamys orlowii, belonging to the Zingiberaceae family, is an endemic species in Vietnam. In the present study, the chemical composition of essential oil (EO) from D. orlowii rhizomes and its inhibitory activities against alpha-amylase, alpha-glucosidase, and tyrosinase were investigated. The gas chromatography - mass spectrometry results demonstrated the presence of four major constituents in the EO, including (E)-citral (37.65%), (Z)-citral (22.13%), geranyl acetate (17.73%), and geraniol (5.90%). In the enzymatic inhibition assays, the EO showed a potent alpha-amylase inhibitory activity (IC50 = 81.86 +/- 0.95 mu g/ml) but had no inhibition of alpha-glucosidase. With respect to the tyrosinase inhibition test, the EO exerted a weak inhibitory activity.