title: Isorhapontigenin: a novel bioactive stilbene from wine grapes.
abstract: Stilbenes are a family of bioactive compounds found in plants. However, only a few stilbenes are present in the human diet. Grape and wine are the main dietary source of stilbenes, resveratrol and piceid being the most common ones. Ultraviolet C light (UVC) postharvest treatment was used to obtain significantly increased stilbene concentration in grapes. A new, previously undescribed-in-grapes stilbene was found after UVC treatment. The process followed to isolate and identify this unknown stilbene is described in the present work. This isolation involved several fractionation steps including counter current chromatography and semi-preparative HPLC due to its low concentration and the presence of structurally related compounds. The structure of the compound was unequivocally identified by NMR spectroscopy analyses including (1)H-NMR; COSY; ROESY; HSQC and HMBC. The compound was identified as isorhapontigenin (ISOR), a stilbene found in traditional Asian medicinal plants. To the best of our knowledge this is the first report of its occurrence in grapes.
authors.affiliation: Instituto de Investigación y Formación Agraria y Pesquera (IFAPA), Rancho de la Merced, Junta de Andalucía, Ctra. Trebujena, Km 3.2, P.O. Box 589, Jerez de la Frontera 11.471, Cadiz, Spain.
authors.forename: María Isabel
authors.initials: MI
authors.lastname: Fernández-Marín
authors.forename: Raúl F
authors.initials: RF
authors.lastname: Guerrero
authors.forename: María Carmen
authors.initials: MC
authors.lastname: García-Parrilla
authors.forename: Belén
authors.initials: B
authors.lastname: Puertas
authors.forename: Tristan
authors.initials: T
authors.lastname: Richard
authors.forename: Miriam Adriana
authors.initials: MA
authors.lastname: Rodriguez-Werner
authors.forename: Peter
authors.initials: P
authors.lastname: Winterhalter
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Monti
authors.forename: Emma
authors.initials: E
authors.lastname: Cantos-Villar
mesh_terms: D002851:Chromatography, High Pressure Liquid; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification; D013267:Stilbenes / Q000737:chemistry* / Q000302:isolation & purification; D014466:Ultraviolet Rays; D027843:Vitis / Q000737:chemistry* / Q000528:radiation effects
chemical_list: D010936:Plant Extracts; D013267:Stilbenes; C432307:isorhapontigenin