Antioxidant activity of prune (Prunus domestica L.) constituents and a new synergist.
Ethanol extract of prune was separated into hexane-soluble and H(2)O-soluble fractions, and the H(2)O-soluble fraction was further separated into a methanol (MeOH) eluate and an H(2)O eluate by Diaion HP-20 column chromatography. The MeOH eluate exhibited the strongest antioxidant activity among the separated fractions evaluated by oxygen radical absorbance capacity (ORAC). Further purification of the MeOH eluate led to isolation of a novel compound, 4-amino-4-carboxychroman-2-one, together with four known compounds (p-coumaric acid, vanillic acid beta-glucoside, protocatechuic acid, and caffeic acid), structures of which were identified by NMR and MS analyses. The ORAC values of these isolated compounds showed 0.15-1.43 units (micromol of Trolox equiv)/micromol, and the new compound showed a remarkable synergistic effect on caffeoylquinic acid isomers. The antioxidant activity of the MeOH eluate was highly dependent on the major prune components, caffeoylquinic acid isomers, with a contribution from the new synergist.
Kayano
Shin-Ichi
S
Research and Development Institute, MIKI Corporation, 12-4 Naruohama 3, Nishinomiya 663-8142, Japan.
Kikuzaki
Hiroe
H
Fukutsuka
Naoko
N
Mitani
Takahiko
T
Nakatani
Nobuji
N
D000975:Antioxidants / Q000302:isolation & purification* / Q000494:pharmacology*; D002109:Caffeic Acids / Q000302:isolation & purification / Q000494:pharmacology; D002839:Chromans / Q000302:isolation & purification / Q000494:pharmacology; D003373:Coumaric Acids / Q000302:isolation & purification / Q000494:pharmacology; D004357:Drug Synergism; D000431:Ethanol; D006586:Hexanes; D062385:Hydroxybenzoates / Q000302:isolation & purification / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D000432:Methanol; D010936:Plant Extracts / Q000737:chemistry*; D011422:Propionates; D027861:Prunus / Q000737:chemistry*; D017382:Reactive Oxygen Species / Q000737:chemistry; D014641:Vanillic Acid / Q000302:isolation & purification / Q000494:pharmacology; D014867:Water
C460240:4-amino-4-carboxychroman-2-one; D000975:Antioxidants; D002109:Caffeic Acids; D002839:Chromans; D003373:Coumaric Acids; D006586:Hexanes; D062385:Hydroxybenzoates; D010936:Plant Extracts; D011422:Propionates; D017382:Reactive Oxygen Species; D014867:Water; C009091:protocatechuic acid; D000431:Ethanol; D014641:Vanillic Acid; C495469:p-coumaric acid; C040048:caffeic acid; D000432:Methanol