Comparative evaluation of antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) methods

Abstract

Ultraviolet—visible (UV—vis) spectrometry, electron paramagnetic resonance spectroscopy, high-performance liquid chromatography, and thin-layer chromatography were used for the evaluation of the antioxidant activity of natural samples. All the methods used free radicals to determine antioxidant capacity and standard antioxidant compounds, usually Trolox or vitamin C, to express the results. In this study, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) methods for the determination of the antioxidant activity of some wines previously separated by high-performance thin-layer chromatography (HPTLC) are statistically compared. The antioxidant activities were quantified based on the calibration curves obtained after elution under the same chromatographic conditions of different quantities of Trolox. Also, the reaction time was established to be between 10 and 30 min. The results show that the values found for DPPH and ABTS assays are well correlated, the...