| Proanthocyanidins also called procyanidins, are a kind of flavones, which are widely applied as agents to treat or prevent cancer, atherosclerosis and other diseases because of their biological activities such as scavenging free radicals and antioxidation . Proanthocyanidins widely exist in many plants such as grape, pine, apple, while grape seeds are often used as raw materials. In this paper the extraction from grape seeds have been studied extensively.The content of proanthocyanidins with spectrophotometeric method was deeply analyzed in this paper. In the colormetry, the vanillin-hydrochloric acid-methanol was used as suitable colour agent, and the proper colour-developed condition was determined by orthogonality test. The proper proportion of vanillin-methanol and hydrochloric acid-methanol was 0.15mg/10mL and 4.50mL/10mL; the reaction temperature was 20±1℃ and the proper reaction time was 15 minutes, much less than 15 hours reported. By measuring the absorbency of different content of standard samples, the linearity range was 0.50-3.00mg/mL and relative coefficient was 0.9987.In this paper, the extraction of oligomeric proanthocyanidins from grape seed is also studied. The optimum conditions of extraction were as follows: the rate of solution to solid 7:1, the temperature 40℃, extraction time 27 hours, the extraction times 3, the concentration of ethanol 60%. The extraction yield could be more than 2.71%.Compared with 4 kinds of absorbent resins, X-5 resin was chosen as the best resin to separate proanthocyanidins, higher quality of products could be obtained under the condition as following: the absorptive velocity is 4 bed volume per hour and desorbtive velocity is 2 bed volume per hour, eluant was 20% ethanol, the purity of the product reached 95.33%. Afterextraction of proanthocyanidins, grape seeds oil could also be obtained from the waste materials, the yield was 14.75% by using Soxhlet extraction with petroleum ether as solvent..
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