The ABTS method was employed to assess the sample's antioxidant activity [18] (link). The procedure commenced with preparing a seven mM ABTS solution, a 140 mM potassium persulfate solution, and the ABTS radical solution. 72.05 g of ABTS was dissolved in 20 mL of distilled water to create the seven mM ABTS solution. The 140 mM potassium persulfate solution was prepared by dissolving 756.91 mg potassium persulfate in 20 mL of distilled water. The ABTS radical solution was generated by combining 20 mL of the seven mM ABTS solution with 352 μL of the 140 mM potassium persulfate solution. This mixture was left in a dark room for 18 hours. Next, 1 mL of the ABTS radical solution was diluted with distilled water to achieve a solution with an absorbance reading of 0.75 at 734 nm. The analysis was done by mixing 25 μL of the sample with 1 mL of the diluted ABTS radical solution, followed by a 6-minute incubation period. Finally, the absorbance was measured using a spectrophotometer at 734 nm. The results were expressed as a percentage of inhibition (%), and the antioxidant analysis was conducted in triplicate. The results are expressed in percent (%) inhibition. The percentage of ABTS inhibition was calculated using the following equation:
(1)