岩藻聚糖硫酸酯低聚糖的制备及其抗氧化活性研究

Preparation and Antioxidative Activity of Low Molecular Weight Fucoidan

探讨H2O2降解岩藻聚糖硫酸酯的条件及其产物的抗氧化活性。采用Cu2+-H2O2体系降解原料Fucoidan,结果发现反应时间越长得到的高分子量的组分越少,而低分子量的低聚糖产量增加;H2O2浓度增高,水解所得主要组分的分子量明显减小;温度升高,水解速度明显加快;产物的硫酸根含量随反应温度和H2O2浓度的降低而增加。用Pyrogallol—Luminol系统对水解产物的抗氧化活性进行了研究,发现硫酸根含量低的Fucoidan水解产物除O2.-的活性较好,其中15%H2O2降解得<5KD的低聚糖清除O2.-的活性明显高于肌肽(IC50为0.65mg/mL),IC50为0.17mg/mL。

The conditions of fucoidan degradation by H2O2 and the antioxidative activities of degradated products studied. The raw fucoidan was degradated by a Cu^2 ＋ -H2O2 assay, the results showed that the percentage of the products of high molecular weight decreased with the reaction time; however, those of low molecular weight increased; the molecular weight of the hydrolysate showed a negative relationship with the concentration of H2O2; the reaction rate of degradation was enhanced marked with increasing temperature; and the SO4^2- content of the oligosaccharides increased with decreasing temperature and H2O2 concentration. The antioxidatire activities of degradated products were assessed by the pyrogallcl-luminol system, the results showed that the O2- scavenging ability of the degradated products of lower SO4^2- contents was better, the fraction with MW〈 5KD（degradated by 15% H2O2） had obvious higher O2 - scavenging ability than Sarcosine（ IC50 = 0.65mg/mL）, whose IC50 was 0.17mg/mL.