稀土金属镧(III)用于配位氧化控制降解寡糖的分子量分布与抗氧活性

Formation of La(III) with Chitosan and the Molecular Weight Distribution of Oligosaccharides by Oxidating Degradation as well as antioxidant activity

在壳聚糖溶液中加入镧离子使形成壳聚糖镧 (III)配合物 ,用H2 O2 对形成的壳聚糖La (III)配合物进行氧化降解 ,测定了降解产物的分子量分布。结果表明壳聚糖镧配合物在过氧化氢的存在下降解迅速 ,降解从大分子量范围开始 ,降解产物寡糖分子量分布窄于目前通用方法。分布指数与寡糖的平均数均分子量有关 ,分子量在 10个糖以上时 ,DP越小 ,分布指数越小。同时对壳聚糖、壳聚糖镧配合物进行了清除O2 - 自由基的对比研究 ,发现壳聚糖镧配合物清除O2 - 自由基活性高于壳聚糖自身。

Complex of chitosan with La(III) were formed by adding LaCl 3·4H 2O to Chitosan solution. H 2O 2 was used to degrade chitosan-La(III) complex, and molecular distribution of degraded products were investigated. The result suggested that the chitosan could be degrade rapidly, the degradation started from higher molecular weight range, the molecular weight distribution of oligosaccharides is much more narrow than that of degradated products of usual methods, such as hydrolysis acidic and oxidizing conditions. The index of molecular weight distribution is changed with the average degradability. When exceeding 10 oligosaccharides, the smaller of the DP, the smaller of the index. The scavenging effect on the superoxide radical (O 2-) and the inhibitory effect on peroxides were also investigated. The results showed that the inhibitory effect on peroxides of chitosan-La(III) is better than that of chitosan.