A new technology of extraction and purification of proanthocyanidins derived from sea buckthorn bark

A new technology involving resin purification of proanthocyanidins extracted from sea buckthorn bark has been studied. By investigating single-factor effects, the main factors affecting proanthocyanidin extraction were identified as extraction temperature, pH and ethanol concentration. A central composite design and response surface analysis were used to determine the optimal parameters of the extraction process (temperature 21 degrees C, pH 5.13, ethanol concentration 65%). The optimal resin for purification, D3520, was selected from 16 different resins by means of static adsorption and dynamic adsorption/desorption tests. After using this resin to purify the crude extract, a proanthocyanidin extract was obtained whose yield and purity were above 80% and greater than 95% respectively. Procyanidin dimers and trimers predominated among oligomer procyanidins of the proanthocyanidin extract according to analyses by high-performance liquid chromatography (HPLC) and HPLC/mass spectrometry. (c) 2005 Society of Chemical Industry.