红枣硒多糖的合成及性质研究

Synthesis and Properties of Selenium Red Jujube Polysaccharides

究了红枣硒多糖的合成工艺、结构及理化性质。采用水热浸提法从红枣中提取出多糖,在硝酸的催化作用下,利用亚硒酸钠对红枣多糖进行分子修饰,合成出红枣硒多糖。利用单因素和正交试验,确定出最佳合成工艺条件;反应温度70℃、反应时间6 h、亚硒酸钠加入量0.3 g、硝酸浓度0.75%,在此条件下,硒含量为4.454 mg/g。红外光谱显示硒多糖中含有C-Se=O键和Se-H键。理化性质表明硒多糖为棕色固体、无臭无味、能缓慢溶解于热水,不溶于乙醇、乙醚、氯仿等有机溶剂;常温下干品的稳定性比液相的好,高温下的稳定性差;红枣硒多糖比红枣多糖有更强的清除超氧负离子自由基、羟基自由基的能力及更强的还原能力。为红枣资源的进一步开发利用提供了理论依据。

Synthesis technology,structures and physicochemical properties of Se-RJP were studied.The Hot-water extraction was used to extract red jujube polysaccharides（RJP）.Selenium red jujube polysaccharides（Se-RJP） were prepareded by employing sodium selenite to modify the polysaccharide under the catalysis of nitric acid.Marking use of the single factor experiment and orthogonal experiment,the optimal reaction conditions were determined reaction temperature was 70 ℃,reaction time was 6 h,the quantite of sodium selenite was 0.3 g,the concentration of nitric acid was 0.75%.At the optimum parameters,the selenium content in Se-RJP reached 4.454 mg/g.The infrared spectrum showed that Se-RJP contained C-Se=O and Se-H.Se-RJP was abrown odorless tasteless solid.Se-RJP can slowly soluble in hot water and cannot soluble in alcohol,ether,chloroform and other organic solvents.The stability test showed that dry Se-RJP were stabler than Se-RJP solution in room temperature,were unstable in high temperature.The experiments of antioxidant effect in vitro and total reducing capacity confirmed Se-RJP had higher reducing capacity and scavenging effects on superoxide anion radical and hydroxide free radicals.The results provide a theoretical basis for further development and use of red jujube resource.