Isolation and purification of dimeric and trimeric procyanidins from grape seeds

An improved method used for the isolation and purification of low-molecular-mass procyanidins (i.e., dimeric B-1, B-2, B-3, B-4, B-1-3-O-gallate, B-2-3-O-gallate, B-2-3'-O-gallate, trimer C-1 and trimer T-2) from grape seeds, is described. Prefractionation in oligomers and polymers was performed by chromatography on an open column (LiChroprep RP-18). The oligomer fraction, rich in dimeric and trimeric procyanidins, was then chromatographed on a Toyopearl TSK HW-40 (F) column. The major fractions obtained from Toyopearl TSK HW 40 (F) chromatography were further separated by semi-preparative HPLC, to obtain pure procyanidins. The main advantages of this method are that it is easy to use, less time-consuming and gives very high yield of dimeric and trimeric procyanidins by each manipulation. (C) 1999 Elsevier Science B.V. All rights reserved.