盐离子浓度对氧自由基吸收能力(ORAC)检测准确性的影响  

Effect of salt ion concentration on the accuracy of oxygen radical absorption capacity(ORAC) detection

作　　者：顾敏[1] 赵谋明[1] 任娇艳[1] 

机构地区：[1]华南理工大学轻工与食品学院,广东广州510641

出　　处：《食品工业科技》2012年第20期84-86,90,共4页Science and Technology of Food Industry

基　　金：国家自然科学基金(31000759);广东省重大科技专项资助项目(2011A080403019);广东省部产学研项目(2011A090200078)

摘　　要：氧自由基吸收能力(ORAC)检测是在抗氧化和应激氧化领域中被广泛使用的抗氧化评价方法。现有ORAC检测方法中,基本未考虑抗氧化物质在分离纯化过程中引入的盐对检测结果的影响。通过在抗氧化标品Trolox中分别添加不同种类及不同浓度盐离子(NH4Cl、CH3COONa、CH3COONH4和NaCl),分析盐离子对ORAC实验结果准确性的影响。结果表明,样品中盐离子的存在使测得的ORAC值都有不同程度的提高,其中CH3COONa的影响最为明显;原因可能是盐的存在影响荧光素的电离,从而改变荧光素的氧化速率。可在标准曲线样品中加入与待测样品同等浓度的盐来消除样品中盐引起的测定误差。The oxygen radical absorbance capacity（ORAC） assay method has been employed extensively in the field of antioxidant and oxidative stress. The ignorance of the effect of salt ion in the sample on ORAC method resulted in the incorrect evaluation of the antioxidant capacity. The present study investigated the effect of salt on ORAC assay＇s accuracy in terms of adding different salt（including NH4Cl,CH3COONa,CH3COONH4 and NaCl） to Trolox,ORAC values increased due to the the salt ions in the sample,especially CH3COONa,which may be attributed to the fact that the change of ionization of fluorescein caused by salt ion lead to the alteration of its oxidation rate. Therefore,measuring error could be eliminated by addition of same concentration of salt ion in tested sample in Trolox for determination of standard curve.

关 键 词：氧自由基吸收能力 盐离子 Trolox氧化 荧光氧化 

分 类 号：TS201.2[轻工技术与工程—食品科学]