茉莉花渣中果胶型多糖的结构特征与免疫调节作用

为探究茉莉花渣中果胶型多糖的结构特征与免疫调节作用，本研究通过水提醇沉、蛋白脱除、阴离子交换柱层析和凝胶柱层析分离得到两种多糖JSP-3和JSP-4。通过相对重均分子量测定、单糖组成测定、部分酸水解液-质联用测定以及核磁共振波谱分析了两种多糖结构特征，最后以小鼠巨噬细胞RAW 264.7为模型，通过探究其对小鼠巨噬细胞的增殖率、吞噬率、ROS产生量以及NO、TNF-α、IL-6分泌量的影响来研究免疫调节作用。结果表明，JSP-3和JSP-4为两种均一多糖，相对重均分子量分别为15.48 kDa和 44.75 kDa，主要由半乳糖醛酸、鼠李糖、半乳糖和阿拉伯糖构成，存在不同比例的半乳糖醛酸聚糖结构域（JSP-3:32.87%±3.53%；JSP-4:68.64%±0.67%）与鼠李糖半乳糖醛酸聚糖结构域（JSP-3:61.12%±3.37%；JSP-4:28.28%±0.46%），说明两者均为果胶型多糖。与对照组相比，JSP-3和JSP-4在12.5~100 μg/mL的浓度范围内无细胞毒性，在一定浓度下能够通过促进小鼠巨噬细胞的吞噬作用，显著增加ROS产生量以及NO、TNF-α和IL-6的分泌量（P<0.05）。在相同浓度下，JSP-4比JSP-3能够刺激细胞分泌更多的NO、TNF-α和IL-6，说明JSP-4具有更强的免疫调节作用，这可能与其更高的半乳糖醛酸结构域比例和相对重均分子量有关。上述研究成果初步证明了茉莉花渣果胶型多糖的免疫调节作用，为其在免疫调节剂方面的应用提供了初步依据。

Structural Analysis and Immunomodulatory Effects of Pectic Polysaccharides Separated from Jasminum sambac Flower Waste

In order to explore the structural characteristics and immunomodulatory effects of pectic polysaccharides in Jasminum sambac flower waste, two polysaccharides, JSP-3 and JSP-4, were separated by water extraction, alcohol precipitation, deproteinization, anion exchange chromatography and gel chromatography. Its structural characteristics were analyzed with relative weight average molecular weight, monosaccharide composition, partial acid hydrolysis-LC-MS and NMR. Finally, the immunomodulatory effects of two polysaccharides were studied by using murine macrophage RAW 264.7 as a model, and measuring the effects on proliferation, phagocytosis, ROS production and secretion of NO, TNF-α and IL-6. The results showed that JSP-3 and JSP-4 were two homogeneous polysaccharides with relative molecular weights of 15.48 kDa and 44.75 kDa, respectively, mainly composed of galacturonic acid, rhamnose, galactose and arabinose, with different proportions of galacturonan domain (JSP-3: 32.87%±3.53%, JSP-4: 68.64%±0.67%) and rhamnogalacturonan domain (JSP-3: 61.12%±3.37%, JSP-4: 28.28%±0.46%), indicating that both are pectic polysaccharides. Compared with the control group, JSP-3 and JSP-4 have no cytotoxic effect within 12.5~100 μg/mL. At a certain concentration, it increased the production of ROS and the secretion of NO, TNF-α and IL-6, also promoted the phagocytosis of mouse macrophages significantly (P<0.05). At the same concentration, JSP-4 could stimulate cells to secrete more NO, TNF-α and IL-6 than JSP-3, indicating that JSP-4 had a stronger immunoregulatory effect, which might be associated with its higher proportion of galacturonan domain and relative molecular weight. The above research results preliminarily proved the immunomodulatory effect of pectic polysaccharide from Jasminum sambac flower waste, and would provide a basis for its potential application in immunomodulators.