目的 优选高山红景天多糖（RSP）的最佳硫酸化修饰条件，提高RSP的抗氧化活性。方法 利用氯磺酸-吡啶法对RSP进行了硫酸化修饰，并通过单因素实验确定了硫酸化反应的最佳工艺条件；应用红外光谱（IR）和扫描电子显微镜（SEM）对RSP和硫酸化高山红景天多糖（S-RSP）的理化性质进行了分析；通过测定RSP和S-RSP对1，1-二苯基-2-三硝基苯肼（DPPH）自由基的清除能力，考察了S-RSP的取代度（DS）与多糖抗氧化活性之间的关系。结果 当氯磺酸与吡啶的体积比为1∶4、反应时间为2 h、反应温度为60℃时，制得的S-RSP的含硫量最大值为18.83%，取代度最大值为2.38。RSP经硫酸化修饰后，增强了其抗氧化活性，S-RSP的DS与DPPH自由基清除能力存在一定的正比例关系。结论 氯磺酸与吡啶的体积比影响S-RSP的DS大小；RSP经硫酸化修饰后通过改变多糖的极性而增加了其抗氧化能力。

Objective To optimize the sulfated modification conditions of Rhodiola sachalinensis polysaccharide (RSP) and improve the anti-oxidant activity of RSP. Methods RSP were sulfated by chlorosulfonic acid-pyridine method, and the optimal conditions for the sulfated modification were determined by single factor experiments. The physical and chemical properties of RSP and sulfated RSP (S-RSP) were analyzed by infrared spectroscopy (IR) and scanning electron microscopy (SEM). The relation between substituting degree (DS) of S-RSP and anti-oxidative activity of polysaccharide was investigated by testing the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging ability of RSP and S-RSP. Results When the volume ratio of chlorosulfonic acid to pyridine was 1:4, the reaction time was 2 h and the reaction temperature was 60℃, the maximum sulfur content of S-RSP was 18.83% and the DS was the highest for 2.38. Moreover, the anti-oxidant activity of RSP was enhanced by the sulfated modification, and there was a certain positive proportional relationship between DS and DPPH free radical scavenging ability of S-RSP. Conclusion The volume ratio of chlorosulfonic acid to pyridine affects the DS of S-RSP, and the sulfated modification can increase the anti-oxidant capacity of RSP by changing its polarity.

国家自然科学基金项目（31401203）；中国博士后科学基金项目（2017M610155）；吉林省分子老年医学重点实验室（20130624003 JC）；吉林省教委科研基金（吉教科合字[2016]第53号）