两种体外评价抗氧化活性方法影响因素分析:DPPH和ABTS

Influence factors analysis of two methods for evaluating antioxidant activity in vitro:DPPH and ABTS assays

目前体外评价抗氧化活性方法在食品、医药和化妆品等领域广泛应用,但没有一种方法可真实准确反映抗氧化剂的“总抗氧化能力”,每种检测方法都存在一定缺点和局限性。DPPH法和ABTS法因快速、简单、成本低、可检测大量样本等优点,被广泛接受并使用,但不同抗氧化剂溶剂、结构、浓度和空间可及性、吸收信号、反应时间等因素对测定结果准确性存在影响。本研究依据影响DPPH法和ABTS法检测准确性的不同因素分析发现,DPPH法更适合评价以有机溶剂为反应溶剂、非极性/极性较小、反应较慢的抗氧化剂,且容易受到抗氧化剂颜色的影响,如色素;光照、金属离子、pH值波动也会影响DPPH法的稳定性。ABTS法更适合评价以水为反应溶剂、极性较大、反应迅速的抗氧化剂。因此,为准确测定抗氧化剂活性,应依据样品特征选择适合方法,同时建议使用至少两种或以上方法,以全面反映抗氧化剂活性。

Currently,in vitro evaluation of antioxidant activity is widely used in the fields of food,medicine and cosmetics,but none of the methods can truly and accurately reflect the“total antioxidant capacity”of antioxidants,and each assay has certain shortcomings and limitations.The DPPH and ABTS methods are widely accepted and used because they are rapid,simple,low-cost,and can detect a large number of samples.However,different antioxidant solvents,structures,concentrations and spatial polarizability,absorption signals,and reaction times have an impact on the accuracy of the results.In this study,based on the analysis of different factors affecting the accuracy of the DPPH and ABTS methods,it is found that DPPH method is more suitable for evaluating antioxidants with organic solvents as reaction solvents,nonpolar/lower polarity,and slower reaction,and the method is easily affected by the color of the antioxidants,such as pigments,light,metal ions,and fluctuations in pH.The ABTS method is more suitable for evaluating antioxidants with water as the reaction solvent,high polarity and rapid reaction.Therefore,in order to accurately determine the antioxidant activity,suitable methods should be selected according to the characteristics of the samples,and it is also recommended to use at least two or more methods to fully reflect the antioxidant activity.