响应面法优化藜麦糠皂苷的提取及抗氧化活性

Optimization of Extraction Conditions for Saponins from Chenopodium quinoa Bran by Response Surface Method and Its Antioxidant Activities

采用超声波浸提法提取皂苷,通过单因素试验考察液料比(A)、乙醇体积分数(B)和超声时间(C)对藜麦糠皂苷得率的影响,并采用Box-Behnken中心组合实验及响应曲面分析法优化藜麦糠皂苷的提取;同时采用还原Fe3+能力及清除1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基、羟自由基(·OH)和超氧阴离子(O2-·)能力分析藜麦糠皂苷抗氧化活性。结果表明,最佳提取工艺条件为液料比39∶1(m L/g),乙醇体积分数74%,超声时间33 min。在此条件下,皂苷得率为23.371 mg/g。抗氧化试验结果表明,藜麦糠皂苷有显著的抗氧化活性,且与皂苷的质量浓度呈剂量依赖性。

The ultrasonic extraction of saponins from Chenopodium quinoa Bran was optimized with the combined use of single- factor method and response surface method based on Box- Behnken design. The antioxidant activities of the extracted saponins was evaluated by DPPH,·OH and O2-·radical scavenging and Fe3＋reducing power assays. The results showed that optimum conditions were as follows： liquid- solid ratio 39∶1（m L/g）, ethanol volume fraction 74%, ultrasonic time 33 min. Under the above optimized conditions,saponins extraction rate in Chenopodium quinoa Bran was 23.371 mg/g. Antioxidant tests indicated that the saponins obtained from Chenopodium quinoa Bran had antioxidant activity. Saponins＇ concentrations and antioxidant activity were in a dose- dependent manner.