摘要
利用ESR和自旋捕集技术,首次观察了不同方法提取的两种褐藻硫酸多糖(SP)对Fenton反应和光照H2O2两个体系产生的·OH清除作用,及对次黄嘌呤/黄嘌呤氧化酶和光照核黄素两个体系产生的O-.2(HO·2)清除作用,并且对其清除·OH和O-.2的动力学进行了研究。结果表明,热提取物(SPh)和冷提取物(SPc)均有明显清除OH和O-.2作用,且呈量效关系。对O-.2的清除率高于对·OH的清除率(84.7%vs69.2%)。SPh对两种自由基的清除效果比SPc好。在光照核黄素体系中SPh30g/L几乎完全清除O-.2,SPc可清除68.9%,而在次黄嘌呤/黄嘌呤氧化酶体系中只需3g/LSPh便可完全清除O-.2。15g/LSPh和30g/LSPc对Fenton反应产生的·OH的清除率分别为77.7%和68.7%。动力学研究表明,SPh与·OH和O-.2反应的表观速率常数分别为7.1×109mol-1·s-1和3230.5mol-1·s-1。实验提示SP可作为一种预防性的抗氧化剂。确证SP清除自由基为研究其抗HIV及肿瘤的机理提供了一条新途径。
The purpose of this study is to investigate the scavenging effects of the sulfated polysaccharides (SP) from brown seaweed Laminaria Japonica(hot water extract SPh and cold water extract SPc)on superoxide radical (O . 2 or HO · 2) and hydroxyl radical ( ·OH) and their spin trapping kinetics by electron spin resonance (ESR) in vitro.The results showed that both SPh and SPc had significant effects of scavenging ·OH and O . 2 with dose effect relationships.The scavenging effects of SPh were better than those of SPc.In the light riboflavin system,30g/L SPh almost completely scavenged O . 2(or HO · 2) and only 3g/L SPh were needed in the xanthine oxidase system.30g/L SPc scavenged 68.9% O . 2.The scavenging effects of 15g/L SPh and 30g/L SPc on ·OH were 77.7% and 68.7%,respectively.The rate constants of SPh for ·OH and O . 2 were 7.1×10 9mol -1 ·s -1 and 3230.5mol -1 ·s -1 respectively.These suggested that SP might be a preventive antioxidant beneficial in treatment for some diseases associated with oxidative stress,including cancer and HIV infections.
出处
《营养学报》
CAS
CSCD
北大核心
1997年第1期32-37,共6页
Acta Nutrimenta Sinica
关键词
褐藻多糖
氧自由基清除
羟基自由基
ESR
sulfated polysaccharides superoxide radical(O . 2 or HO · 2) hydroyl radical( ·OH) electron spin resonance (ESR)