Study On Extraction, Separation And Purification Of Proanthocyanidins From Grape (Vitis Davidii Fo(?)x) Seeds

The technics of extraction and purification of proanthocyanidins from grape seedswere studied, with grape (Vitis davidii Fo(?)x) "Ziqiu" as the experimental material inthis paper, and the content of proanthocyanidins B₂ by this method was determined.The results were as follows:Five extraction conditions were studied by orthogonal experiment: concentration ofsolvent, extraction temperature, extraction times, ratio of solvent to grape seed, andextraction times. With the selectivity of extraction of optimal condition, the optimalextraction conditions were as follows: solvent was 60% ethanol, ratio of solvent togrape seed was 7:1, temperature was 60℃, extraction times were 2h. Extraction yieldof proanthocyanidins was about 76.9%, the content of proanthocyanidins in oligomersproduct was 42.3%.The purification technics of proanthocyanidins from grape seeds by macroporousabsorption resin was studied.YWD-06C resin was selected as sorbent by static testing,and the optimal adsorption conditions were determined by orthogonal experiment:temperature was 20℃, adsorption time was 6h, pH=4; the optimal desorptionconditions were: solvent 60% ethanol, pH=4, desorption time was 6h, temperaturewas 25℃;The adsorption speed was 4BV/h and the desorption speed was 2BV/h,which were established by dynamic testing. The content of proanthocyanidins afterpurified was 92.57%, the content of B₂ was 33.5%, which was determined by HPLC.The characteristic of this technics was as follows: the method of macroporous resinscan remove most of the impurity, improving the content of proanthocyanidins,concentrate proanthocyanidins B₂, the strongest antioxidants of proanthocyanidins indifferent polymerization degree.The separation condition of purified proanthocyanidins was studied preliminaryby preparative high-performance liquid chromatography (PHPLC), which makes asolid step to the further separation to the proanthocyanidins.