title: Isolation and characterization of some antioxidative compounds from the rhizomes of smaller galanga (Alpinia officinarum Hance).
abstract: Antioxidative compounds were isolated from the methanol extract of fresh rhizome of smaller galanga (Alpinia officinarum Hance). Seven phenylpropanoids (1-7) were finally obtained by reversed-phase HPLC, 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-hydroxyphenyl)-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-hydroxyphenyl)-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.
authors.affiliation: The United Graduate School of Agricultural Science, Department of Bioprocessing, Faculty of Agriculture, Gifu University, 1-1 Yanagido, Gifu City, Gifu 501-1193, Japan.
authors.forename: Tram Ngoc
authors.initials: TN
authors.lastname: Ly
authors.forename: Makoto
authors.initials: M
authors.lastname: Shimoyamada
authors.forename: Koji
authors.initials: K
authors.lastname: Kato
authors.forename: Ryo
authors.initials: R
authors.lastname: Yamauchi
mesh_terms: D000475:Alkenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D032429:Alpinia / Q000737:chemistry*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D010936:Plant Extracts / Q000737:chemistry; D027343:Rhizome / Q000737:chemistry*
chemical_list: D000475:Alkenes; D000975:Antioxidants; D010636:Phenols; D010936:Plant Extracts