目的 研究苦豆子多糖SAP的一级结构及其抗肿瘤活性。方法 采用高效凝胶渗透色谱法、红外广谱、GC-MS结合NMR法解析SAP的结构；考察SAP对CT26荷瘤小鼠的抗肿瘤活性。结果 SAP为半乳甘露聚糖，其相对分子质量为9.6×10⁵，以1，4-β-D-Man为主链，在其某些C-6的位置上连接1，6-α-D-Gal片段，末端为半乳糖。体内抗肿瘤实验结果表明，SAP高、中、低剂量组对CT26荷瘤小鼠肿瘤生长有抑制作用，且呈剂量依赖关系，对CT26荷瘤小鼠的抑瘤率可达44.03%。结论 SAP的结构确定为其构效关系研究奠定理论基础，该多糖有望进一步开发成为高效低毒的抗结肠癌新药。

Objective To study the structure of Sophora alopecuroides polysaccarides (SAP) and its antitumor activity on CT26 transplanted tumor in mice. Methods The structure was characterized by high-performance gel permeation chromatography (HPGPC), gas chromatography-mass spectrometer (GC-MS), infrared spectroscopy (IR), and nuclear magnetic resonance spectroscopy (NMR). And then the anticancer activity of CT26-bearing mice was investigated in vivo. Results The results showed that SAP was consisted of D-mannopyranose and D-galactopyranose residues. The main chain of the galactomannan comprises β-(1,4)-linked D-mannopyranose residues, with branches of galactose, linked to the carbohydrate core through α-D-Gal (1,6) linkage. SAP could inhibit the tumor proliferation of CT26-bearing mice in a dose-dependent manner with inhibitory rate of 44.03% at high dose. Conclusion Structure determination of SAP provides the theoretical basis for structure-activity relationship study. And it is expected to be further developed as a new antitumor drug with high efficiency and low toxicity.

天津市科委抗癌重大科技专项（12ZCDSY19200）；天津市卫生局科技基金项目（2012KY30）