title: Glyceraldehyde bridging between flavanols and malvidin-3-glucoside in model solutions.
abstract: Hydroxyl radicals (.OH) seem to have an important role in the oxidation of wine constituents and the production of important electrophilic aldehydes and ketones. In this experiment, glyceraldehyde, a .OH oxidation product of glycerol, recently described in wine, reacts with (+)-catechin, (-)-epicatechin, and malvidin-3-glucoside (Mv3gl), in model solutions, yielding new condensed phenolic compounds. The adduct compounds formed were separated by means of reversed phase liquid chromatography and detected and characterized using UV-vis and electrospray ionization mass spectrometry. Flavanol-flavanol and anthocyanin-flavanol adducts linked with glyceraldehyde yielded compounds with m/z ratios for their main ions, in positive ion mode, of 653.2 for the (+)-catechin dimer or the (-)-epicatechin dimer and 855.5 for Mv3gl/(+)-catechin or Mv3gl/(-)-epicatechin dimers. The possible occurrence of these compounds in wine is suggested, and the potential role of these and related reactions in wine aging is discussed.
authors.affiliation: Department of Viticulture and Enology, University of California, Davis, CA 95616, USA.
authors.forename: V Felipe
authors.initials: VF
authors.lastname: Laurie
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Waterhouse
mesh_terms: D000872:Anthocyanins / Q000737:chemistry*; D005419:Flavonoids / Q000737:chemistry*; D005960:Glucosides; D005985:Glyceraldehyde / Q000737:chemistry*; D006801:Humans; D008956:Models, Chemical; D012996:Solutions; D014920:Wine / Q000032:analysis*
chemical_list: D000872:Anthocyanins; D005419:Flavonoids; D005960:Glucosides; D012996:Solutions; D005985:Glyceraldehyde; C458419:malvidin-3-glucoside