沙棘多糖脱蛋白工艺的优化研究

Optimization of De-protein Process for Polysaccharide of Hippophae rhamnoides

植物多糖纯化过程中脱蛋白是较为重要的环节之一,为了提高多糖纯化效率,对沙棘多糖脱蛋白的工艺进行了优化研究。先选取了3种不同方法脱蛋白,即三氯乙酸法(TCA法)、沙维积法(Sevag法)、酶法与Sevag法联用,通过比较不同方法处理后的蛋白含量及多糖含量来确定最佳的脱蛋白方法。结果表明,对于三氯乙酸法而言,5%的三氯乙酸脱蛋白效率最高且多糖损失最小;对于Sevag法,反复处理5次脱蛋白效率相对较高且多糖损失率较小;对于酶法与Sevag法联用,酶法+Sevag法2次进行脱蛋白效果最好。并且3种方法相比,酶法与Sevag法联用脱蛋白效率相对最高,且多糖损失率最小。因此进一步设计正交试验来确定木瓜蛋白酶法脱蛋白的最佳条件,结果表明,木瓜蛋白酶法脱蛋白的最佳条件是酶加量5 mg/mL,酶解温度60℃,pH6,且此条件下的蛋白清除率为73.58%。

Removing protein is one of the important elements in the process of plant polysaccharide purification. In order to improve the efficiency of polysaccharide purification,the present paper mainly investigated the technology of protein removal from Hippophae rharnnoides polysaccharide,so as to optimize the process of de-protein. Three different methods of removing protein, the acetocaustin method （TCA）, the Sevag method and the combination of enzyme with Sevag method, were compared by analyzing the content of protein and polysaccharide content in the polysaccharide liquor after treated with above approaches. The results showed that, for the method of TCA, 5% trichloroacetic acid had the highest efficiency for removing protein and had the minimum loss of polysaccharide. For the method of Sevag,treatment repeatedly for five times had the relatively good efficiency of protein removal and less loss rate of polysaccharide. For the method of enzyme plus Sevag,treatment for twice is the best choice. By comparison,the combination of enzyme with Sevag is the bset among the three methods. In addition, the paper further designed a orthogonal experiment to determine the best condition of deproteinised method of papain, which indicated that the best condition was the papain volume of 5 mg/mL, hydrolytic temperature of 60 ℃ and pH of 6,under which the protein clearance rate reached to 73. 58%.