Proanthocyanidins are polymerized by (+) - catechin, (-) - epicatechin and (-) - epicatechin - 3 - gallate. It is difficulty to separate and analyze because of a variety of isomers of different degrees of polymerization. The antioxidant activity of proanthocyanidins largely depends on the degree of polymerization. Proanthocyanidins were separated according to the degree of polymerization, and the property of different products was evaluated. Ethanol concentration of 10% ~40% and 60% were selected in gradient eluting by AB -8 resin. The eluting recovery achieved 98. 63%. According to the average degree of polymerization and antioxidant activity of proanthocyanidins, ethanol 0 ~ 10% eluent contained only monomer, ethanol 12% ~32% eluent contained mainly OPC, ethanol 32% ~60% eluent contained PPC. The an-tioxidation activity of 12% ~32% eluent was the highest with the free radical clearance rate 44. 85% which is equivalent of VC 19. 38 μg/mL.%原花青素由(+)-儿茶素、(-)-表儿茶素、(-)-表儿茶素没食子酸酯聚合而成,聚合度、单体及连接键的不同使得原花青素具有多种异构体,造成分离分析困难.原花青素的抗氧化活性受聚合度影响,按聚合度大小对原花青素分级分离,对产品性能进行评价.用10％～ 40％和60％乙醇溶液对吸附在AB-8大孔树脂上的原花青素梯度洗脱,原花青素洗脱收率达到98.63％.分析各乙醇洗脱液中原花青素平均聚合度和抗氧化活性,0％ ～ 12％乙醇洗脱液中为单体,12％ ～32％洗脱液中主要为低聚体,32％～60％洗脱液中为高聚体,12％ ～ 32％洗脱液原花青素抗氧化活性最高,自由基清除率为44.85％,维生素C当量浓度为19.38 μg/mL.
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