红芪多糖的复合酶联合超声提取工艺、理化特性及抗氧化活性的研究

Complex enzyme combined with ultrasound extraction technology,physicochemical properties and antioxidant activity of Hedysarum polysaccharides

利用复合酶联合超声波提取技术（MC）,以红芪多糖得率和含量为综合指标,通过单因素和正交试验,筛选最优提取组合,并分析了复合酶联合超声提取多糖（HPS-MC）的不同组分和热水浸提多糖（HPS-R）的物理化学特性及体外抗氧化活性。结果表明,复合酶配比对红芪多糖得率和含量影响均达到显著效应,而超声功率能显著提高红芪多糖含量;最佳工艺参数为复合酶配比1∶1、超声功率105 W、超声时间60 min、酶解p H 5,多糖得率和质量分数分别为（14.01±0.64）%,（92.45±1.47）%;与HPS-R相比,HPS-MC的相对分子质量、绝对黏度和蛋白质含量均降低,而糖醛酸含量增加;抗氧化体系中,多糖质量浓度在1~7 g·L^（-1）时,HPS-MC比HPS-R的抗氧化活性高,且相对分子质量最低的HPS-MC（80%）随试验浓度的增大呈显著量效关系。综上所述,MC是一种简单方便、经济环保的提取技术,该法提取的HPS具有明显的抗氧化活性。

In this study,complex enzymes combined with ultrasonic extraction technology（ MC） were used,to select optimal extraction combinations by single factor and orthogonal test,with Hedysarum polysaccharides yield and content as the comprehensive indexes.The components,physicochemical properties and antioxidant activity of Hedysarum polysaccharides from complex enzyme combined with ultrasonic extraction（ HPS-MC） and the Hedysarum polysaccharides from hot water extraction（ HPS-R） were analyzed. The results showed that： complex enzymes had significant effect on the yield and content of Hedysarum polysaccharides,and the ultrasonic power could significantly improve the content of Hedysarum polysaccharides. The optimum technological parameters were as follows： complex enzyme ratio 1∶ 1,ultrasonic power 105 W,ultrasonic time 60 min,and enzymatic hydrolysis pH 5,achieving（ 14. 01 ± 0. 64） % and（ 92. 45 ± 1. 47） % respectively for the yield and content of Polysaccharides. As compared with HPS-R,the molecular weight,absolute viscosity and protein content of HPS-MC were decreased,while the content of uronic acid was increased. In the antioxidant system,the concentration of polysaccharide was within the range of 1-7 g·L^（-1）; the antioxidant activity of HPS-MC was higher than that of HPS-R,and HPS-MC（ 80%） with the lowest molecular weight showed a significant dose effect relationship with the increase of the experimental concentration. In conclusion,MC is a simple,convenient,economical and environmentally friendly extraction technology,and the Hedysarum polysaccharides extracted by this method have obvious antioxidant activity.