3.6.2. Ferric-Reducing Antioxidant Power Assay (FRAP)

The protocol described in detail by Nazir et al. [29] was used for the assessment of reducing the power of extracts. Briefly, the FRAP solution (190 μL) was first prepared (10 mM TPTZ, 20 mM FeCl₃, 6H₂O and 300 mM acetate buffer pH 3.6; ratio 1:1:10 (v/v/v)). The reaction mixture was prepared by adding 10 μL of the plant extract to 190 µL of FRAP solution. The mixture was incubated at (25 ± 1 °C) for 15 min. A BioTek Synergy II absorbance microplate reader was used for measurement of absorption at 630 nm. The assay was performed in triplicate and reducing potential expressed in Trolox C-equivalent antioxidant activity (TEAC).