Efficient isolation of major procyanidin A-type dimers from peanut skins and B-type dimers from grape seeds

Laboratory of Food Chemistry, Wageningen University, Bomenweg 2, 6700 EV Wageningen, The Netherlands; RIKILT – Institute of Food Safety, Bornsesteeg 45, 6700 AE Wageningen, The Netherlands; INRA, UMR SPO, 2 Place Viala, 34060 Montpellier, France
Food Chemistry 01/2009; DOI: 10.1016/j.foodchem.2009.04.047
Source: OAI

ABSTRACT In order to fully explore the biofunctional potential of proanthocyanidins (PA), isolated and well-characterised PA dimers are of great importance. Current methods to obtain pure A- and B-type dimers are laborious, because they comprise multiple chromatographic steps, often yielding only one or two specific dimers. In the current study, an efficient isolation procedure is described, to isolate a large variety of A-type dimers from peanut skins and B-type dimers from grape seeds. Yields increased 20–400 times for A-type dimers and about 10 times for B-type dimers compared to other methods with a lesser number of chromatographic steps. Dimers isolated from peanut skins were identified as; epicatechin-(2-O-7, 4-8)-catechin (A1), epicatechin-(2-O-7, 4-8)-epicatechin (A2), epicatechin-(2-O-7, 4-6)-catechin, epicatechin-(2-O-7, 4-8)-entcatechin, isolated from peanut skins for the first time, and epicatechin-(4-6)-catechin (B7). Dimers from grape seeds were identified as; epicatechin-(4-8)-catechin (B1), epicatechin-(4-8)-epicatechin (B2), catechin-(4-8)-catechin (B3) and catechin-(4-8)-epicatechin (B4).

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