壳聚糖硫酸酯金属配合物的抗氧化活性

摘要

The O_2~(·-)and ~·OH scavenging activities of the complexes of sulfation chitosan with copper(Ⅱ)or zinc(Ⅱ)and DMW chitosan were investigated.Colorimetric method was used,where phenzine methosulphate(PMS)/dinucleotide-reduced(NADH)and Fe/H_2O_2 were used as producing reagents and Nitro blue tetrazolium (NBT) and Fanhonghua as detecting reagents for O_2~(·-)and ~·OH.As expected,we obtained several satisfying resulte, as follow:rnFirstly,compared with DMW chitosan,the complexes of sulfation chitosan with copper(Ⅱ)or zinc (Ⅱ)had the stronger inhibition effect on O_2~(·-).For example,when mass concentration of samples was 0.025 g/L,the O_2~(·-)scavenging activity of the complexes of sulfation chitosan with copper(Ⅱ)and the complexes of sulfation chitosan with zinc(Ⅱ)were 94.18%and 93.19%respectively.Secondly,scavenging activity of the complexes of sulfation chitosan with copper(Ⅱ)or zinc(Ⅱ)(67.39%,60.46%,3.2 g/L)on ~·OH was between low molecular weight chitosan(20 ku,88.06%,3.2 g/L)and high molecular weight chitosan(761 ku,18.71%,3.2 g/L).Thirdly,low molecular weight chitosan had stronger scavenging effect rnon O_2~(·-)and ~·OH than high molecular weight chitosan.At 1.6 g/L,the scavenging activity of low molecular weight chitosan(20 ku)on O_2~(·-)reached 54.69%,while that of high molecular weight chitosan(761 ku)was 35.50%.Finally,the scavenging activity of several samples increased with increase in their mass concentration.However,the complexes of sulfation chitosan with copper(Ⅱ)or zinc(Ⅱ)had a quite strong scavenging action to O_2~(·-),their scavenging activity barely had obvious changing over 0.025 g/L.This result also showed that the complexes of sulfation chitosan with metalion were very effective antioxidant.%以吩嗪硫酸甲酯-NADH为超氧阴离子自由基(O_2~(·-))产生、检测体系和EDTANa_2-Fe(Ⅱ)-H_2O_2为羟自由基(~·OH)产生、检测体系,对壳聚糖硫酸酯铜、锌配合物和不同分子质量壳聚糖进行了抗O_2~(·-)和~·OH自由基的活性研究.结果表明,壳聚糖硫酸酯金属配合物对于O_2~(·-)自由基的清除能力明显高于壳聚糖,在质量浓度为0.025 g/L时,壳聚糖硫酸酯铜配合物对O_2~(·-)自由基的清除能力达到94.18%,壳聚糖硫酸酯锌配合物达到93.19%;壳聚糖硫酸酯铜、锌配合物对~·OH自由基的清除能力(67.39%、60.46%)低于相同分子质量的壳聚糖(88.06%),而高于高分子质量壳聚糖761 ku(18.71%);壳聚糖分子质量大小对O_2~(·-)和~·OH自由基的清除能力有较大影响,质量浓度为1.6 g/L壳聚糖分子质量为20 ku时,对O_2~(·-)清除率达54.69%,而分子质量在761 ku时,对O_2~(·-)清除率仅为35.50%;各样品对O_2~(·-)和~·OH自由基的清除能力均随着质量浓度的增加而上升,壳聚糖硫酸酯铜、锌配合物在相当低的浓度下(0.025 g/L)就可以达到明显清除O_2~(·-)自由基的效果(≥90%).