二次正交旋转超声制备黄芪多糖及其抗氧化性分析

Preparation and Antioxidant Activity of Astragalus Polysaccharides by Quadratic Rotation-Orthogonal Combination Design

摘要: 该文主要研究利用超声辅助来提取黄芪多糖。通过醇沉、旋转蒸发浓缩，获到提纯过后的黄芪多糖粉末。然后再通过苯酚–硫酸法来测定出多糖的含量。以单因素实验的实验结果为基础来设计二次正交旋转试验，从而得出黄芪多糖提取率的最佳工艺条件。即当液料比为1:7，超声时间为15 min，水浴时间为50 min，水浴温度为70℃时，提取率靠近最佳值为2.19%。并且通过对黄芪多糖进行红外光谱解析，可以证实实验制备所获得的样品是多糖。然后对该实验制备出来的黄芪多糖进行抗氧化性测定。通过羟基自由基清除作用来测定其抗氧化性的能力大小。运用了芬顿法和水杨酸法两种方法，测定出当黄芪多糖的浓度在1 mg∙mL⁻¹时，自由基的清除率分别为15.58%和33.2%。从而证明了黄芪多糖具有良好的抗氧化能力。

Abstract: This paper mainly studies the use of ultrasound to extract the polysaccharide. The polysaccharide powder is obtained after purification by the concentration of alcohol and spin evaporation. The polysaccharide is then measured by the phenol sulfate method. According to the experimental results of single-factor experiment, the optimum technological conditions of the extraction rate of the polysaccharide were obtained. When liquid ratio is 1:7, ultrasonic time for 15 min, water bath time is 50 min, water bath temperature of 70˚C, the extraction yield close to the optimal value of 2.19%. And by analyzing the infrared spectra of Astragalus polysaccharide, it can be proved that the samples obtained were polysaccharide. The antioxidant properties of Astragalus polysaccharide were determined by the experiment. The antioxidant ability was determined by hydroxyl radical removal. Using the two methods of fenton and salicylic acid, the free radical removal rate was 15.58% and 33.2%, respectively, when the polysaccharide concentration was 1 mg∙mL⁻¹. It is proved that the polysaccharide has good antioxidant ability.