枳椇果梗不同极性多酚及抗氧化活性研究

以不同极性有机溶剂对枳椇果梗多酚进行萃取分离，对各部分多酚进行紫外-可见光谱扫描确定其紫外吸收特性；以FC法测定总酚含量，通过清除DPPH自由基、ABTS+ ·能力测定和Fe3+还原法，对不同极性多酚体外抗氧化活性进行评价。结果表明：液-液萃取可以实现不同极性多酚的有效分离，枳椇果梗不同极性多酚萃取物均有特征紫外吸收；不同极性部分的多酚含量、抗氧化活性有显著差异。枳椇果梗多酚含量和抗氧化活性强弱次序为：水相＞正丁醇相＞乙酸乙酯相＞氯仿相。枳椇果梗多酚以极性酚为主。

Separation and Antioxidant Activity of Polyphenols with Different Polarities from Hovenia acerba Fruit

Different polyphenol extracts (crude methanol extract and its fractions soluble in ethyl acetate, chloroform, n-butanol and water) obtained from Hovenia acerba fruit stalks using organic solvents with different polarity were tested for their UV absorption characteristics in the range of 200－700 nm and polyphenol contents, and their antioxidant activity was assessed based on the ability to scavenge DPPH and ABTS free radicals and reduce ferric ions in vitro. The results indicated that liquid-liquid extraction was a successful method for separating polyphenols with different polarities. The crude extract and its different fractions had different spectral characteristics. A significant difference in total polyphenol content and antioxidant activity was observed among the crude extract and its different fractions. Four different fractions of the crude extract could be ranked in the following order: water-soluble fraction ＞ n-butanol-soluble fraction ＞ ethyl acetate-soluble fraction ＞ chloroform-soluble fraction. Therefore, polar polyphenols were dominant in Hovenia acerba fruit stalks.