摘要
以吩嗪硫酸甲酯—还原型辅酶Ⅰ烟酰胺腺嘌呤二核苷酸(NADH)为超氧阴离子自由基(O2.-)产生、检测体系和EDTANa2-Fe(Ⅱ)-H2O2为羟自由基(.OH)产生、检测体系,对不同分子量壳聚糖和硫酸酯衍生物进行了抗O2.-和.OH自由基的活性研究。结果表明,壳聚糖分子量大小对O2.-和.OH自由基的清除能力有较大影响。质量浓度为1.6 g/L和壳聚糖分子量为9×103时,对O2.-清除率达85.86%,而分子量在7.6×105时,对O2.-清除率仅为35.50%;壳聚糖硫酸酯对于O2.-自由基的清除能力明显高于壳聚糖;在质量浓度为0.05 g/L时,低分子量壳聚糖硫酸酯对O2.-自由基的清除能力达到86.26%;壳聚糖硫酸酯对.OH自由基的清除能力(89.82%)低于相同分子量的壳聚糖(91.22%),而高于高分子量壳聚糖7.6×105(16.77%);低分子量壳聚糖硫酸酯对O2.-和.OH自由基的清除能力高于高分子量壳聚糖硫酸酯;各样品对O2.-和.OH自由基的清除能力均随着质量浓度的增加而上升,壳聚糖硫酸酯在相当低的质量浓度下(0.1 g/L)就可以达到明显清除O2.-自由基的效果(≥90%)。
The O2^· - and · OH scavenging activities of DMW chitosans and sulfated chitosans of corresponding molecular weight were investigated. Colorimetric method was used, by which phenzine methosulphate （PMS）/dinucleotide-reduced（NADH） and Fe/H2O2 were used as producing reagent and Nitro blue tetrazolium（NBT） and Fanhonghua as detecting reagent for O2^· - and · OH. We obtained several satisfied results, as follows ： Firstly, low molecular weight chitosans and their derivatives show stronger scavenging effects on O2^· - and · OH than high molecular weight chitosan and their derivatives. For example, when the mass concentration of samples is 1.6 g/L, the O2^· - scavenging activity of low molecular weight chitosan （9 × 10^3） and high molecular weight chitosan （7.6 × 10^5） are 85.86% and 35.50% respectively. Secondly, compared with DMW chitosans, DMW sulfated chitosans show stronger inhibition effect on O2^· - At 0. 05 g/L, the scavenging activity on O2^· - reaches to 86.26% for low molecular weight chitosan sulfate（9 × 10^5）, but that of low molecular weight chitosan （ 9 × 10^3 ） is 85.86% when mass concentration of the sample is 1.6 g/L. Thirdly, scavenging activity of chitosan sulfates（9 × 10^3, 89. 82%, 1.2 × 10^5, 59.68%, 3.2 g/L） on OH is between those of low molecular weight chitosan（9 × 10^3, 91.22% , 3.2 g/L） and high molecular weight chitosan（1.2 × 10^5, 44. 11%, 7.6 × 10^5, 16.77%, 3.2 g/L）. Fourthly, low molecular weight chitosan sulfates show more effective scavenging activities on O2^· - and · OH than high molecular weight chitosan sulfates. Finally, the scavenging activities of DMW chitosan and their sulfated derivatives increase with the increase in their mass concentration. However, sulfated chitosans show quite strong scavenging action on O2^· - At 0. 2 g/L, the scavenging activities reach to 95.87% and 91.96% respectively, but their scavenging activities barely increase over 0. 2 g/L. This resuh also shows sulfated chitosans are very effective antioxidant.
出处
《应用化学》
CAS
CSCD
北大核心
2005年第9期958-961,共4页
Chinese Journal of Applied Chemistry
基金
青岛市科技局资助项目(H11022506)
