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作 者 ：孙曦晓;刘再枝;杜新琦;赵春建*;王化;杨磊;汪贵斌;祖元刚

期 刊 ：植物研究 2014年 34卷 03期 页码：428-432

关键词：杜仲多糖；DPPH自由基的清除能力；铁还原能力；

Keywords:Eucommia ulmoides polysaccharide, DPPH free-radical scavenging ability, ferric-reducing power, vitamin C,

摘 要 ：以杜仲树皮为原料，采用超声辅助法提取杜仲多糖，考察了预浸泡时间、超声功率、超声时间、超声温度、料液比和提取次数对杜仲多糖得率的影响，最佳提取条件为：预浸泡时间2 h，超声功率250 W，超声时间30 min，超声温度40℃，料液比1∶12 g·mL^-1，提取次数2次。在上述提取条件下提取杜仲多糖，多糖得率为1.94%。此外，对杜仲多糖的抗氧化活性进行了分析评价。结果表明，在相同浓度下，杜仲多糖对DPPH自由基的清除能力高于维生素C。然而，杜仲多糖的铁还原能力低于维生素C的铁还原能力,并且与浓度呈正相关。

Abstract:Ultrasonic-assisted extraction was used for the extraction of polysaccharide from Eucommia ulmoides bark. The effects of the pre-soaking time, the ultrasonic power, the extracting time, the ultrasonic temperature, the ratio of liquid to solid and the extraction times were examined. The optimal conditions for ultrasound extraction were obtained as following: pre-soaking time 2 h, extraction power 250 W, extracting time 30 min, ultrasonic temperature 40℃， liquid to solid ratio 1∶12 g·mL^-1, and extraction 2 times. The highest polysaccharide yield (1.94%) was obtained under the optimal extraction condition. In addition, the antioxidant activity of polysaccharide from E.ulmoides was analyzed and evaluated. The results showed that the DPPH free-radical scavenging ability of polysaccharide is much higher than that of vitamin C at the same concentration. While compared with vitamin C, it exhibited a moderate and concentration-dependent ferric-reducing power.

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