基于ORAC评价多酚类化合物抗氧化活性

摘要

采用氧自由基清除能力(ORAC)方法考察20种多酚类化合物的抗氧化活性。结果表明，该方法具有较优的线性关系(R2=0.997）；检测限(LOD）和定量限(LOQ）为0.5～3.1μmol·L-1，精密度＜18%，准确度91%～105%。比较20种多酚类化合物抗氧化活性，对羟基苯甲酸类化合物中，鞣花酸和没食子酸具有较强的抗氧化活性；对羟基肉桂酸类以咖啡酸及其衍生物抗氧化活性最高；在类黄酮组分中，黄烷-3-醇表现出优良的抗氧化特性，黄酮醇次之。ORAC 可作为评价多酚类化合物抗氧化的简便、高效的标准化检测方法。%The oxygen radical absorbance capacity (ORAC) method was validated, and then ORAC values of selected 20 phenolic compounds were determined. The results indicated that linearity (R2 =0.997), limit of detection and limit of quantification (0.5—3.1 μmol·L-1), precision (<18%), accuracy (91%—105%) were determined. And ellagic acid and gallic acid had strong antioxidant activity in p-hydroxy benzoic acid compounds. Caffeic acid and its derivatives had highest antioxidant activity in hydroxy cinnamic acid. In the flavonoid constituents, flavan-3-ols showed good antioxidant properties, followed by flavonol. ORAC was considered as simple, efficient detection method of standardization for evaluation of antioxidant activity of the phenolic compounds.