浒苔硒多糖的制备及其活性研究

摘要

以自制的浒苔多糖为原料,在硝酸催化下与亚硒酸钠进行硒化反应,制备了浒苔硒多糖.通过单因素实验和正交实验确定最佳合成条件为:亚硒酸钠与浒苔多糖的质量比1.0∶1、反应时间8h、反应温度60℃、硝酸体积分数0.5％,此条件下合成的浒苔硒多糖的硒含量为512.3μg·g-1,其单糖组成为D-甘露糖∶L-鼠李糖∶D-半乳糖醛酸∶D-葡萄糖∶D-木糖=0.01∶0.80∶0.12∶0.65∶0.09(物质的量比).光谱分析表明产品中含有亚硒酸酯基团.与浒苔多糖相比,浒苔硒多糖清除有机自由基DPPH的能力明显增强,在1.0～10.0 mg·mL-1浓度范围内具有一定的还原能力,但清除羟自由基(·OH)的能力变化不大.%Selenium Enteromorpha poIysaccharides(Se-EP) were synthesized from sodium selenite and isolated Enteromorpha polysaccharides(EP) with the catalysis of nitric acid.Through single factor experiment and orthogonal experiment,the optimal reaction conditions were determined as follows:the mass ratio of sodium selenite to EP was 1.0:l,the reaction time was 8 h,the reaction temperature was 60℃ ,the volume fraction of nitric acid was 0.5%.The selenium content in Se-EP reached 512.3 μg · g-1 and the monosaccharide compositions were D-mannose,L-rhamnose,D-galacturonic acid,D-glucose and D-xylose,with a molar ratio of 0.01:0.80: 0.12:0.65:0.09.From the UV-Vis spectrum and infrared spectrum.it was shown that Se-EP contained selenium acid ester group.Compared to EP,the scavenging capability of Se-EP to DPPH radical was significantly enhanced.And Se-EP had reducing capability at the concentration range of 1.0~10.0 mg · mL-1.But the scavenging capability to ·OH had no obvious increase.