Antioxidative compounds isolated from the rhizomes of smaller galanga (Alpinia officinarum Hance).
Antioxidative compounds were isolated from the methanol extract of fresh rhizome of smaller galanga (Alpinia officinarum Hance). Seven phenylpropanoids (1-7) were obtained and their structures were elucidated by MS and NMR analyses. They comprised the two known compounds, (E)-p-coumaryl alcohol gamma-O-methyl ether (1) and (E)-p-coumaryl alcohol (6); and the five novel compounds, stereoisomers of (4E)-1,5-bis(4-hydroxy-phenyl)-1-methoxy-2-(methoxymethyl)-4-pentene (2a and 2b), stereoisomers of (4E)-1,5-bis(4-hydroxyphenyl)-1-ethoxy-2-(methoxymethyl)-4-pentene (3a and 3b), (4E)-1,5-bis(4-hydroxy-phenyl)-1-[(2E)-3-(4-acetoxyphenyl)-2-propenoxy]-2-(methoxymethyl)-4-pentene (4), (4E)-1,5-bis(4-hydroxyphenyl)-2-(methoxymethyl)-4-penten-1-ol (5), and (4E)-1,5-bis(4-hydroxyphenyl)-2-(hydroxymethyl)-4-penten-1-ol (7). Compounds 1-7 were detected for the first time as constituents of galanga rhizomes and exhibited antioxidative activities against the autoxidation of methyl linoleate in bulk phase.
Ly
Tram Ngoc
TN
Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu City, Gifu 501-1193, Japan.
Shimoyamada
Makoto
M
Kato
Koji
K
Yamauchi
Ryo
R
D032429:Alpinia / Q000737:chemistry*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification*; D008041:Linoleic Acids / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D010084:Oxidation-Reduction; D027343:Rhizome / Q000737:chemistry*
D000975:Antioxidants; D008041:Linoleic Acids; C005575:methyl linoleate