title: Antioxidant polyphenols from tart cherries (Prunus cerasus).
abstract: Montmorency and Balaton tart cherries were lyophilized and sequentially extracted with hexane, ethyl acetate, and methanol. Methanolic extracts of dried Balaton and Montmorency tart cherries (Prunus cerasus) inhibited lipid peroxidation induced by Fe(2+) at 25 ppm concentrations. Further partitioning of this methanol extract with EtOAc yielded a fraction that inhibited lipid peroxidation by 76% at 25 ppm. Purification of this EtOAc fraction afforded eight polyphenolic compounds, 5,7,4'-trihydroxyflavanone (1), 5,7, 4'-trihydroxyisoflavone (2), chlorogenic acid (3), 5,7,3', 4'-tetrahydroxyflavonol-3-rhamnoside (4), 5,7,4'-trihydroxyflavonol 3-rutinoside (5), 5,7,4'-trihydroxy-3'methoxyflavonol-3-rutinoside (6), 5,7,4'-trihydroxyisoflavone-7-glucoside (7), and 6, 7-dimethoxy-5,8,4'-trihydroxyflavone (8), as characterized by (1)H and (13)C NMR experiments. The antioxidant assays revealed that 7-dimethoxy-5,8,4'-trihydroxyflavone (8) is the most active, followed by quercetin 3-rhamnoside, genistein, chlorogenic acid, naringenin, and genistin, at 10 microM concentrations.
authors.affiliation: Bioactive Natural Products Laboratory, Department of Horticulture and National Food Safety and Toxicology Center, East Lansing, Michigan 48824, USA.
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.forename: M G
authors.initials: MG
authors.lastname: Nair
authors.forename: G M
authors.initials: GM
authors.lastname: Strasburg
authors.forename: A M
authors.initials: AM
authors.lastname: Booren
authors.forename: J I
authors.initials: JI
authors.lastname: Gray
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification; D005419:Flavonoids; D005612:Freeze Drying; D005638:Fruit / Q000737:chemistry*; D015227:Lipid Peroxidation; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification; D010936:Plant Extracts / Q000032:analysis*; D011108:Polymers / Q000737:chemistry* / Q000302:isolation & purification; D059808:Polyphenols
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D011108:Polymers; D059808:Polyphenols