褐藻硫酸多糖铁配合物的稳定性及其清除自由基的作用

STABILITY OF SEAWEED POLYSACCHARIDE IRON COMPLEX AND ITS ACTIVITIES ON SCAVENGING FREE RADICALS

目的对褐藻硫酸多糖(SP)和SP作为配体合成的一种新型的功能性补铁剂褐藻硫酸多糖铁复合物(SPIC)的理化性质、结构组成,以及自由基清除能力做了对比研究。方法通过SP与Fe(Ⅲ)在适当浓度和条件下络合生成SPIC,用苯酚法测定SP和SPIC的总多糖含量、Hodgson法测定二者的硫酸根含量和Folin酚试剂法测定蛋白含量,红外光谱分析结构,以及电子自旋共振(ESR)结合自旋捕捉检测二者对自由基的清除作用。结果SP与SPIC都具有很好的稳定性且二者的多糖含量相当,而SPIC中蛋白质含量较SP中低,硫酸根含量约为SP的1/2,Fe(Ⅲ)的含量为21.22%。红外光谱分析,可以鉴别SPIC含有稳定的FeOOH核的类型。二者都有清除自由基的作用,但SPIC对超氧自由基的清除作用更强,而对羟自由基清除作用减弱。结论SPIC中铁的络合,有可能达到既补铁,又发挥SP可清除自由基抗氧化功能的双重作用。

Objective To study the component, structure of seaweed sulfated polysaccharides iron complex （SPIC） and its activity of scavenging free radicals. Method SPIC was synthesized with Fe^3＋ and seaweed polysaccharides （SP） isolated from seaweed. The functional components and stability between SP and SPIC were measured with physico-chemical property and infrared spectra, and their activity of scancenging free radicals was detected with ESR. Results Both SPIC and SP had good stability and almost equivalency in content .But the content of sulfate was almost half of SP while protein was much lower in SPIC than that in SP. The investigation with infrared spectra indicated that the structure of SPIC had been an interfacial complex of FeOOH core. SPIC and SP could scavenge free radicals, but SPIC was highly active in scavenging superoxide anion and less active in scavenging peroxide hydroxyl. Conclusion The chelator SPIC from SP and Fe^3＋ is feasible to exert not only the role of iron supplement but antioxidant activity.