Relevance and Standardization of In Vitro Antioxidant Assays: ABTS, DPPH, and Folin–Ciocalteu

Figure 2

The number of exchanged electrons per molecule as a function of incubation time at 25°C for caffeic acid (CA), chlorogenic acid (CGA), gallic acid (GA), and Trolox in DPPH assay in methanol (thin purple) or DPPH assay in the mixture of methanol and buffer (pH 7.4) (thick purple) and ABTS assays in MilliQ water (thin green) or buffer (pH 7.4) (thick green). Black lines correspond to the number of OH groups in the molecule. (a) Caffeic acid (CA), (b) chlorogenic acid (CGA), (c) gallic acid (GA), (d) trolox.

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