玉竹多糖的微波超声提取及其抗氧化研究

Study on Extraction and Antioxidation of Polysaccharide from Polygonatum Odoratum by Microwave and Ultrasonic

以玉竹为原料,水为溶剂,微波和超声波辅助对玉竹中多糖进行提取,在单因素实验基础上,选取微波功率、超声温度、液料比为自变量,玉竹多糖的提取率为响应值,采用Box-Behnken中心组合设计和响应面分析法对其提取工艺进行研究;并对提取的玉竹多糖的还原力、DPPH·和·OH自由基的清除能力进行了测定。建立了回归方程的预测模型,在乙醇浓度为70%、超声时间为8 min时,确定最佳提取条件为:微波功率250 W、超声温度50℃、液料比30∶1,此条件下玉竹多糖的提取率为8.5 g/100 g;当玉竹多糖浓度为0.85 mg/mL时对DPPH·和·OH自由基清除率分别达到34.58%和97.65%。中心组合设计-响应面法可在连续范围内进行分析,具有实验周期短、精密度高的优点,抗氧化性研究结果表明,玉竹多糖是一种具有开发潜力的天然抗氧化剂,结果可为玉竹多糖产品的开发提供参考依据。

Based on the single factor experiment,microwave power,ultrasonic temperature,liquid to material ratio were selected as independent variables,and the extraction rate of Polygonatum odoratum polysaccharide was selected as response value.The extraction process was studied by Box-Behnken central composite design and response surface analysis.The reducing power,DPPH and OH radicals of the polysaccharide were determined.The prediction model of regression equation was established.When the ethanol concentration was 70%and the ultrasonic time was 8 min,the optimal extraction conditions were determined as follows:the microwave power was 250 W,the ultrasonic temperature was 50℃,and the ratio of liquid to solid was 30∶1.Under this condition,the extraction rate of Polygonatum odoratum polysaccharide was 8.5 g/100 g.When the concentration of the Polygonatum odoratum polysaccharide was 0.85 mg/mL,the scavenging rates of DPPH and OH radicals were 34.58%and 97.65%,respectively.Box-Behnken Center combination design and the method of response surface analysis can be used to analyze in a continuous range,which has the advantages of short experimental period and high precision.The results of antioxidant research showed that Polygonatum odoratum polysaccharide was a natural antioxidant with development potential,and the results can provide reference for the development of the Polygonatum odoratum polysaccharide products.