目的 分离纯化三七药渣中主要多糖组分，分析其单糖组成，并对比研究各组分多糖的抗氧化活性。方法 采用水提醇沉法提取三七药渣粗多糖；经DEAE Fast Flow阴离子交换柱、Sephadex G-50柱色谱法进行分离纯化。采用高效凝胶渗透色谱(HPGPC)法测定其相对分子质量及纯度，通过扫描电子显微镜(Scanning Electron Microscope，SEM)、傅里叶变换红外光谱仪(Fourier Transform Infrared spectroscopy，FT-IR)、HPLC-衍生化等方法对各组分多糖的单糖组成和初级结构进行分析。分析其抗氧化能力以及对RAW 264.7细胞氧化损伤的保护作用。结果 分离得到3个多糖组分(PNPS-0、PNPS-0.2、PNPS-0.3)，3者的单糖组成和比例存在差异：PNPS-0主要由D-葡萄糖(52.28%)和D-半乳糖(34.14%)组成；PNPS-0.2主要由D-半乳糖(40.89%)、D-阿拉伯糖(19.38%)和D-葡萄糖(12.25%)组成；PNPS-0.3主要由D-葡萄糖醛酸(40.43%)、D-半乳糖(22.61%)和D-葡萄糖(18.32%)组成。抗氧化结果表明，PNPS-0.3的总还原能力最强，对DPPH自由基、OH^-自由基、ABTS自由基以及超氧阴离子自由基的清除活性最高，对RAW 264.7细胞氧化损伤保护作用最好，并呈现浓度相关性。结论 从三七药渣中得到了3种具有抗氧化活性的多糖片段，抗氧化活性与多糖结构密切相关。为三七资源的二次开发利用提供了新的研究思路。

Objective To separate and purify the main polysaccharide components from Panax notoginseng residues, analyze its monosaccharide composition and compare its antioxidant activities. Methods The crude polysaccharides from P. notoginseng residues (PNPS) were extracted by water extraction and alcohol precipitation, and separated and purified by DEAE Fast Flow anion exchange column and Sephadex G-50 column. The relative molecular mass was analyzed by HPGPC and the monosaccharide composition and primary structure were preliminarily identified by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), HPLC of derivatizing method. The antioxidant capacity and the protective effect of polysaccharide components on oxidative damage of RAW264.7 cells were explored. Results Three polysaccharide components (PNPS-0, PNPS-0.2, and PNPS-0.3) were isolated and purified. There were differences in monosaccharide composition and proportion among the three: PNPS-0 was mainly composed of D-glucose (52.28%) and D-galactose (34.14%), PNPS-0.2 was mainly composed of D-galactose (40.89%), D-arabinose (19.38%) and D-glucose (12.25%) and PNPS-0.3 was mainly composed of D-glucuronic acid (40.43%), D-galactose (22.61%) and D-glucose (18.32%). The antioxidant results showed that PNPS-0.3 had the strongest total reducing ability, the highest scavenging activity on DPPH free radical, OH^- free radical, ABTS free radical and superoxide anion free radical, and the protective effect on oxidative damage of RAW 264.7 cells was the best in a concentration dependent manner. Conclusion Three polysaccharide fragments with antioxidant activity were obtained from P. notoginseng residues. The antioxidant activity was closely related to the structure and composition of polysaccharide. Therefore, this study provides a new research idea for the secondary development and utilization of P. notoginseng resources.

国家自然科学基金项目(81760642)；国家自然科学基金项目(82060645)；云南省科技重大专项(202002AA100004-2)；云南省科技重大专项(202102AA310045)；云南省科技重大专项(202002AA1000056)；云南省应用基础研究计划面上项目(202101AT070099)