响应面法优化超声辅助提取蔓菁多糖工艺及其体外抗氧化性研究

Optimization of Ultrasonic Assisted Extraction Process by Response Surface Methodology and Antioxidant Activity in Vitro for Polysaccharides from Turnip

通过响应面试验优化超声辅助提取蔓菁多糖工艺,并对其体外抗氧化性进行研究。经过单因素试验考察液料比、提取温度、提取时间和超声功率对蔓菁多糖得率的影响,用Design-Expert 8.0.6软件进行四因素三水平的试验设计,并以多糖得率为响应指标进行响应面分析,得到蔓菁多糖的最佳提取条件。通过对羟基自由基(·OH)的清除能力来评价蔓菁多糖的抗氧化活性。结果表明,蔓菁多糖的最优提取条件为:液料比44∶1(mL/g)、提取温度57℃、提取时间56 min、超声功率为180 W,在此条件下蔓菁多糖得率为65.43%,与预测值的相对误差为0.12%;蔓菁多糖对·OH的清除能力强于抗坏血酸,半抑制浓度(half inhibitory concentration,IC50)为0.415 mg/mL。故此优化试验有效可行且蔓菁多糖具有较强的抗氧化性。

Response surface methodology was applied to optimize the ultrasonic-assisted extraction technology of polysaccharides from turnip and the antioxidant activity of polysaccharides in vitro was studied.Single factor experiment was used to explore the effects of solvent-to-solid ratio,extraction temperature,extraction time and ultrasonic power on extraction yield.On this basis,the process conditions were optimized by Design-Expert 8.0.6 software for the response surface analysis.The antioxidant activity of the turnip polysaccharides was evaluated using the scavenging experiments of hydroxyl radicals(·OH).The results showed that the optimal extraction conditions were solvent-to-solid ratio of 44∶1(mL/g),extraction temperature of 57℃,extraction time of 56 min,ultrasonic power of 180 W.Under these optimal conditions,the yield of turnip polysaccharides was 65.43%and the relative error with the predicted value was 0.12%.Turnip polysaccharides had better ability to scavenge·OH than ascorbic acid,and the half inhibitory concentration was 0.415 mg/mL.Therefore,the optimization experiment is effective and feasible,and the turnip polysaccharide has strong antioxidant activity.