An interlaboratory comparison of methods used to assess antioxidant potentials¹

Abstract

Many analytical methods are used to measure the antioxidative activity of substances yet little is known about the comparability of the test results between laboratories. After an initial evaluation of a broad range of methods conducted by one laboratory, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, the trolox equivalent antioxidant capacity (TEAC) assay, the lipid assay (or 2,2'-azobis(2-aminepropane) (ABAP) assay) and the thiobarbituric acid (TBA) assay were selected to be evaluated in the interlaboratory study. The antioxidative potentials of trolox, tocopherol, lipochroman-6, ascorbic acid, 4-methyl-brenzcatechin, and/or 3,5-di-tert-butyl-4-hydroxytoluene (BHT) were assessed using each of the methods. These methods were then evaluated in respect of their reproducibility and classification properties. Based on the results of this study, the DPPH assay followed by the TEAC assay yielded the best results based on reproducibility and sensitivity both within one laboratory and between laboratories. The results of the interlaboratory study were then compared with the single center results obtained from the commercially available photochemolumiescence (PCL) kit. To assess the transferability of chemical data to biological systems, they were also compared with the single center results obtained using the cell-based Dichlorodihydrofluoresceine (DCFH) assay.

Phenolic Content, Antioxidant Potential, and Antimicrobial Activities of Fruit and Vegetable By-Product Extracts

“…Therefore, the use of at least two different analytical approaches to test the antioxidant capacity of specific substrates is recommended. [39] Buenger et al [40] reported that the DPPH˙ assay, followed by the ABTS˙+ assay, yield the best results (based on reproducibility and sensitivity). These tests, involving chromogen compounds of a radical nature, are also the most common antioxidant capacity assays, used for their ease, speed and sensitivity.…”

Antioxidant activities of fractions from longan pericarps

“…However, the action of free radicals and active oxygen can be balanced by a system of antioxidant defenses, including antioxidant compounds and enzymes (Gutteridge & Halliwell, 1992). Synthetic compounds such as butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) and tertiarybutylhydroquinone (TBHQ), are widely employed as preservatives in the food and pharmaceutical industry nowadays (Buenger et al, 2006). But there are numerous reports on adverse effects of synthetic antioxidants such as toxicity and carcinogenicity (Chotimarkon et al, 2008).…”

Antioxidant Activity of Different Solvent Fractions from Prunella vulgaris var. lilacina

“…It reported that these assays require relatively standard equipment and yield the fast and most reproducible results (Buenger et al, 2006). From these results, it was demonstrated that the n-BuOH fraction from 70% EtOH crude extract of Prunella vulgaris var.…”