该论文研究了酶解糖化下的滇黄精多糖结构和免疫活性，以探究酶解糖化下的黄精多糖结构特征及免疫活性的影响。结果表明，酶解糖化黄精多糖（SPKP）的多糖和还原糖含量分别为94.05%、4.1%。多糖结构分析表明，SPKP的红外光谱在1 016~1 147和931 cm-1处有吡喃糖特征吸收峰；单糖组成及摩尔比为阿拉伯糖:半乳糖:葡萄糖:甘露糖:果糖=0.032:0.117:0.419:0.048:0.383，重均分子量（Mw）为3 820 u。甲基化结果表明SPKP主要的糖苷键连接方式为→4)-Glcp-(1→，占比47.1%，分支度为34.1%，结合碘碘化钾和刚果红实验结果可以推测SPKP是一种含有复杂分支的三股螺旋多糖。RAW264.7细胞实验结果表明，酶解糖化黄精多糖在比较广的浓度范围内无毒性，均能促进细胞增殖，且有较高的细胞吞噬能力和NO水平，因此可以推测SPKP具有较好的免疫活性，且与其多糖结构有一定的关系。该研究可以为多糖与免疫活性的构效关系以及黄精新炮制方法的开发提供一定参考。

The structural characteristics and immunomodulatory activity of Polygonatum kingianum Coll. et Hemsl polysaccharides were investigated under conditions of enzymatic saccharification. The results revealed that among the products of enzymatic saccharification in P. kingianum (SPKP), the contents of polysaccharides and reducing sugars accounted for 94.05% and 4.1%, respectively. Structural analysis of the polysaccharides using Fourier transform infrared spectroscopy revealed that these had furanose-specific absorption peaks at 1 016~1 147 and 931 cm-1, whereas the monosaccharide composition and molar ratios were arabinose: galactose: glucose: mannose: fructose (0.032: 0.117: 0.419: 0.048: 0.383), and the molecular weight (Mw) was 3 820 u. The main type of linkage was →4-Glcp-1→ (47.1%), and the corresponding branching degree was 34.1%. Combined with the results of the iodine–potassium iodide and Congo Red staining experiments, SPKP were inferred to be a three-stranded helical polysaccharides containing complex branches. The findings of RAW264.7 cell experiments indicated that P. kingianum polysaccharides are non-toxic within a wide range of concentrations and can promote cell proliferation, phagocytic capacity, and production of NO. Accordingly, it can be speculated that SPKP have good immunomodulatory activities, which are associated with polysaccharide structures. Our findings in this study may provide a reference for determining the structure-function relationships between polysaccharides and immunomodulatory activity, as well as the development of new methods for processing P. kingianum.

财政部和农业农村部：国家现代农业产业技术体系资助项目（CARS-21）