2001 年 47 巻 2 号 p. 167-171
Constituents of the fruits of greater cardamom (Amomum subulatum) Were fractionated into three fractions, the dichloromethane extract, and the ethyl acetate-soluble and water-soluble fractions of the 70% aqueous acetone extract. The ethyl acetate-soluble fraction showed a high radical-scavenging activity against 1, 1-Biphenyl-2-picrylhydrazyl (DPPH). Four compounds were isolated from the ethyl acetate-soluble fraction, and their structures were ascribed to protocatechualdehyde (1), protocatechuic acid (2), 1, 7-bis(3, 4dihydroxyphenyl)hepta-4E, 6E-dien-3-one (3) and 2, 3, 7-trihydroxy-5-(3, 4-dihydroxy-Estyryl)-6, 7, 8, 9-tetrahydro-5H-benzocycloheptene (4) on the basis of spectroscopic evidence. This is the first isolation of these compounds from greater cardamom. In particular, 4 was a new type of cyclic diarylheptanoid. DPPH radical-scavenging activity of these compounds was measured by colorimetric analysis. Compounds 1 and 3 showed stronger activity than such natural antioxidants as a-tocopherol and L-ascorbic acid. Compounds 2 and 4 were comparable to α-tocopherol and L-ascorbic acid.
