3.5.4. Metal Chelating Activity Assay

The plant’s hydroalcoholic extract’s ability to chelate metals compared to the EDTA was estimated using the method of Zengin et al. [85]. In brief, a mixture of the extract solution (2 mL of ethanol containing 200 µg of extract) and ferrous chloride (25 µL, 2 mM) was added to 100 µL of ferrozine to inchoate the color. The mixture’s absorbance was recorded at 562 nm against a blank (2 mL of the extract plus 200 µL of the ferrous chloride without ferrozine). The standard calibration curve of EDTA was prepared, and the chelating activity of the extract was calculated as the equivalent of the EDTA.