裙带菜多糖的超声波提取及其性质研究

Study on the ultrasonic-assisted extraction of polysaccharide from Undaria pinnatifida and its characterization

采用超声波法提取裙带菜中的多糖,利用苯酚-硫酸比色法测定多糖的含量,研究了提取温度、提取时间、料液比三个因素对多糖提取率的影响,并通过正交实验得出多糖提取的最佳工艺;同时对其理化性质进行初步研究,探讨了温度、pH、硼酸和Ca2+对多糖构象的影响。实验结果表明:裙带菜多糖的最佳提取工艺条件为:料液比1∶45(g/mL)、提取温度80℃、提取时间40min,该条件下裙带菜多糖的提取率达到了7.56%。超声提取得到的裙带菜多糖不含淀粉,但含有少量蛋白质和硫酸基团;温度和硼酸对多糖的构象没有影响,酸和碱对多糖构象产生较小影响,但Ca2+可显著破坏多糖的构象。

In this paper, Undaria pinnatifida polysaccharides（UPPS） were extracted by ultrasonic-assisted method. The content of polysaccharides was measured by phenol-sulfate method. Effects of three factors on the extraction, including extraction temperature,extraction time and solid/solvent ratio were studied by single factor and the optimum extraction conditions were then determined through the orthogonal experiment. Meanwhile,physical and chemical properties of the resultant polysaccharide were also concerned in this paper. Results showed that these optimum extraction conditions as follows-solid/liquid ratio 1：45 （g/mL）,extraction temperature 80℃ ,and extracting duration 40min. Under such conditions,the yield of the polysaccharide reached 7.56%. Physicochemical analysis revealed that the polysaccharide contained protein and sulfate radicals,but no starch was detected in it. The structure of the Undaria pinnatifida polysaccharides remained intact after exposure to high temperature or H3B04. However,the polysaccharide was slightly affected by acid or alkali and the conformation of the polysaccharide was significantly damaged by Ca^2＋.