Characterization of Procyanidins of Vitis vinifera Variety Tinta del Pais Grape Seeds

Abstract

[EN]HPLC has been applied for the analysis of procyanidins in seeds grapes of Vitris vinifera variety Tinta del País. Use of a diode arrat detector permitted the location on ghe chromatogram of peaks corresponding to procyanidins and procyanidin gallates and also a possible procyanidin esterified with p-coumaric acid. A seed extract was fractionated by gel chromatography on Sephadex LH-20 and then by preparative HPLC isolate compunds and permit their identification. Structures were characterized by TLC, complete and partial acid hydrolisis, enzymatic hydrolisis and thiolysis in the presence of phenylmethanethiol with later desulfuration of the benzyl thioethers obtained. The heptamers could be the compound wiht the highest degree of polymerization present in the extract, although only dimer, trimer and tetramer procyanidins were isolated