室温下龙须菜多糖提取工艺及免疫活性研究

Optimization of Extraction Technology of Polysaccharides from Gracilaria lemaneiformis at Room Temperature and Their Immunocompetence

本实验对室温下龙须菜多糖浸提工艺、分离纯化及多糖免疫活性进行研究。L9(34)正交试验结果显示,提取次数和提取时间是影响多糖得率的主要因素(p<0.05),最佳工艺为料液比1:20(m/V)、提取时间12h、提取次数3次,多糖得率为9.96%;蛋白去除实验结果显示:Sevag法处理5次效果较好,去除率达32%。免疫活性实验显示,室温下浸提多糖(GCp)刺激小鼠淋巴细胞增殖作用优于同浓度下采用高温提取工艺(100℃)和高压提取工艺(121℃)浸提多糖。采用冻融、超滤和Sevag法对龙须菜粗GCp进行纯化,获得GCp-1、GCp-2、GCpF1、GCpF2和GCp-S五种多糖。免疫活性研究表明,6种多糖均具有刺激淋巴细胞增殖作用,且表现剂量依赖性,其中GCp和超滤获得的多糖GCpF1、GCpF2优于冻融多糖GCp-1、GCp-2和除蛋白多糖GCp-S。

The extraction technology of crude polysaccharides from Gracilaria lemaneiformis （GCp） at room temperature was optimized by orthogonal test, and the inducing effects of GCp and different fractions of GCp obtained by different methods on proliferation of mouse lymphocyte were investigated. The results indicated that extraction times and extraction time were the significant factors affecting the yield of GCp. The maximum yield of 9.96% was obtained by extracting three times for 12 h at the solid to liquid ratio of 1：20. 32% of protein contained in crude polysaccharide could be removed by Sevag method （repeated 5 times）. The inducing effect of GCp extracted at room temperature on proliferation of mouse lymphocyte was significantly higher than thoseot obtained at 100 ℃ and 121 ℃ at the same concentration. Five kinds of polysaccharides were obtained by ultra- filtration, freeze-thaw and Sevag method （GCpF1 and GCpF2 by ultra-filtration, GCp-1 and GCp-2 by freeze-thaw, and GCp- S by Sevag method）. The immunocompetence assay revealed that all GCp and the five polysaccharide fractions were able to induce proliferation of mouse lymphocyte in a concentration-dependent manner, and GCp, GCpF1 and GCpF2 were more active than GCp-1, GCp-2 and GCp-S.