title: Survey of grapevine Vitis vinifera stem polyphenols by liquid chromatography-diode array detection-tandem mass spectrometry.
abstract: Grapes and red wine prepared from Vitis vinifera L. contain a variety of polyphenols. Some information is available about the polyphenols of the seeds and leaves of grapevine, but considerably less is known about the polyphenols of woody stems. In this paper, we describe the results of a study of polyphenolic compounds in grapevine stems. We demonstrate how a combination of reversed phase high-performance liquid chromatography with ultraviolet-diode array detection and electrospray ionization-tandem mass spectrometry ion-trap detection enables characterization of a phytochemical mixture of considerable complexity. As the polyphenol source, the stems of three frost-hardy grapevine varieties [Hasaine (Hasansky) sladki, Zilga, and Yubilei Novgoroda] were used. The main group of methanol-extractable polyphenols of stems consists of trans-resveratrol and its derivatives including oligomers and glucosides. As minor components of the extract, stilbenoid piceatannol as well as a number of nonstilbenoid polyphenols, mostly flavan-3-ols and phenolic acids glucosides, were determined. The total polyphenol content of the grapevine stems depends on the variety, whereby the stems of cultivar Yubilei Novgoroda with white grapes contain significantly less of both groups of polyphenols.
authors.affiliation: Department of Food Hygiene and Control, Estonian University of Life Sciences, Kreutzwaldi 58A, 51014 Tartu, Estonia.
authors.forename: Tõnu
authors.initials: T
authors.lastname: Püssa
authors.forename: Janar
authors.initials: J
authors.lastname: Floren
authors.forename: Paul
authors.initials: P
authors.lastname: Kuldkepp
authors.forename: Ain
authors.initials: A
authors.lastname: Raal
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005419:Flavonoids / Q000032:analysis*; D010636:Phenols / Q000032:analysis*; D018547:Plant Stems / Q000737:chemistry*; D059808:Polyphenols; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013267:Stilbenes / Q000032:analysis; D027843:Vitis / Q000737:chemistry*
chemical_list: D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D013267:Stilbenes