STUDY ON CHEMICAL CONSTITUENTS AND BIOLOGICAL ACTIVITIES OF ALPINIA KWANGSIENSIS T. L. WU AND S. J. CHEN COLLECTED IN VIETNAM

Three compounds named ester methyl- trans-p -coumarate (1), 7-hydroxy-6-methoxycoumarin (2), and (+) -gallocatechin (3) have been isolated from the ethyl acetate fraction of methanol extract of Alpinia kwangsiensis roots collected in Thai Nguyen province. Their structures were elucidated on the basis of spectroscopic data and by comparison with their spectral data reported in literature. This is the first isolation of three compounds from this species. The ethyl acetate fraction was found to be active against bacterias as Staphylococcus aureus and Bacillus subtilis with the IC 50 values ranging at 74.65 mg/ml and 80.54 mg/ml, respectively. This fraction also showed antioxidant activity through DPPH test with the EC 50 value 87.98 mg/ml.