title: Composition of grape skin proanthocyanidins at different stages of berry development.
abstract: The composition of grape (Vitis vinifera L. cv. Shiraz) skin proanthocyanidins has been determined at different stages of berry development. Beginning approximately 3 weeks after fruit set and concluding at commercial ripeness, the composition of isolated skin proanthocyanidins was determined using the following analytical techniques: elemental analysis, UV-Vis absorption spectroscopy, reversed-phase HPLC after acid-catalysis in the presence of excess phloroglucinol, gel permeation chromatography, electrospray ionization mass spectrometry (ESI-MS), and (13)C NMR. On the basis of these analyses, berry development was correlated with an increase in proanthocyanidin mean degree of polymerization, an increase in the proportion of (-)-epigallocatechin extension subunits, and increases in the level of anthocyanins associated with the proanthocyanidin fraction. Additionally, data acquired from ESI-MS of the isolates following acid-catalysis in the presence of excess phloroglucinol is consistent with pectin-bound proanthocyanidins.
authors.affiliation: Department of Horticulture, Viticulture and Oenology, Adelaide University, Waite Campus, PMB 1, Glen Osmond, South Australia 5064, Australia. James.Kennedy@orst.edu
authors.forename: J A
authors.initials: JA
authors.lastname: Kennedy
authors.forename: Y
authors.initials: Y
authors.lastname: Hayasaka
authors.forename: S
authors.initials: S
authors.lastname: Vidal
authors.forename: E J
authors.initials: EJ
authors.lastname: Waters
authors.forename: G P
authors.initials: GP
authors.lastname: Jones
mesh_terms: D000872:Anthocyanins / Q000032:analysis*; D002850:Chromatography, Gel; D005638:Fruit / Q000737:chemistry* / Q000254:growth & development; D010860:Pigments, Biological / Q000032:analysis; D044945:Proanthocyanidins; D013057:Spectrum Analysis
chemical_list: D000872:Anthocyanins; D010860:Pigments, Biological; D044945:Proanthocyanidins; C013221:proanthocyanidin