Activityread at 560 nm after a 10 min incubation period in the dark. Trolox was used as standard and quercetin and rutin were used as positive controls. All analyses were done in triplicates. Superoxide anion scavenging activity was calculated using the following equation: ? of inhibition?Absorbance lank? bsorbance ample??=Absorbance lank?X 100 Results were expressed as IC50, i.e. concentration of the plant extract required to inhibit 50 of the superoxide anion radicals.Nitric oxide radical scavenging activityThis assay was used to evaluate the radical scavenging activity of antioxidants in the plant extracts against a chemically-synthesised radical, 2,2-diphenyl1-picryl-hydrazyl (DPPH). In this assay, 100 l of the extract (0?00 g/ml) was added to 600 l of DPPH reagent (100 M), mixed thoroughly and incubated in the dark at room temperature for 20 min. The decrease in absorbance was measured at 517 nm. The experiment was carried out in triplicate using Trolox as standard. Quercetin and rutin were used as positive controls. The DPPH radical scavenging activity was calculated using the following equation: ? of inhibition?Absorbance lank? bsorbance ample??=Absorbance lank?X 100 Results were expressed as IC50, i.e. concentration of the plant extract required to inhibit 50 of the DPPH radicals.Superoxide anion radical scavenging activityThe nitric oxide radical scavenging activity was conducted based on the method of Rai, Wahile, Mukherjee, Saha, Mukherjee (2006) [21]. Briefly, 0.5 ml of sodium nitroprusside (10 mM) was mixed with 0.5 ml PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/28854080 of the plant extract (0?00 g/ml). The mixture was kept in the dark at room temperature for 150 min. Thereafter, 1 ml of sulfanilic acid reagent was added to 0.5 ml of the reaction mixture and incubated for 5 min. One ml of 0.1 naphthyl ethylene diamine dihydrochloride was then added, mixed and incubated for 30 min at 25 before the absorbance was read at 540 nm. Trolox was used as standard while quercetin and rutin were used as positive controls. All analyses were done in triplicate. Nitric oxide scavenging activity was calculated using the following equation: h of inhibition?Absorbance lank ??Absorbance ample ??=Absorbance lank ?X 100 Results were expressed as IC50, i.e. concentration of the plant extract required to inhibit 50 of the nitric oxide radicals.Hydroxyl radical scavenging activityThe superoxide anion radical scavenging activity was measured based on the method by Siddhuraju Becker (2007) [20]. Superoxide anion reacts with nitroblue tetrazolium (NBT) to generate a colored compound which can be measured at a wavelength of 560 nm. The reaction mixture contained 0.1 M phosphate buffer (pH 7.4), 150 M NBT, 60 M phenazine methosulphate, 468 M NADH and the plant extracts (0?00 g/ml), added in that sequence. Absorbance of the mixture wasThis assay measures the competition between deoxyribose and antioxidants in the plant extract for hydroxyl radicals generated from the Fe3+/ascorbate/H2O2 XR9576 cost system. Briefly, 0.2 ml of plant extract was mixed with 0.2 ml of ferric chloride (100 mM), 0.2 ml of hydrogen peroxide (1.25 mM), 0.2 ml of deoxyribose (2.5 mM) and 0.2 ml of ascorbic acid (100 mM). The reaction mixture was then incubated for 1 h at 37 before the addition of 1 ml of thiobarbituric acid solution and 1 ml of trichloroacetic acid. The mixture was heated for 30 min at 80 and cooled on ice. Absorbance of the mixture was measured spectrophotometrically at 532 nm. Each analysis was done in tripl.
