COMPARATIVE NON-ENZYMATIC AND ENZYMATIC ANTIOXIDANT POTENTIAL SCREENING IN SPECIES OF GENUS URTICA

Objective: The current study has been conducted to analyze the potential of antioxidant activity found in two species of genus Urtica, i.e., Urtica dioica and Urtica urens. Methodology: The antioxidant analysis was performed on the crude extract of root, stem and leaves of both the plants, employing both non-enzymatic and enzymatic methods. For non-enzymatic antioxidant activity determination, methods such as 2, 2- diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and Ferrous Reducing Antioxidant Power (FRAP) were opted, whereas for enzymatic analysis, the specific activity of catalase and ascorbate peroxidase assay was examined. Results and Conclusion: The antioxidant activity found via DPPH assay in U. urens ranges from 32.72±0.22 μg/ml to 43.06±1.12 μg/ml and in U. dioica it ranges from 14.28±0.22 μg/ml to 30.88±0.278 μg/ml, while by using FRAP assay the antioxidant activity range found to be 10.412±2.235 μg/ml to 14.005±2.55 μg/ml and 1.526±0.146 μg/ml to 8.014±1.38 μg/ml in U. urens and U. dioica, respectively. The specific activity of antioxidant enzymes catalase and ascorbate peroxidase were exhibited in a range of 16.11±2.146 U/mg to 26.869±6.811 U/mg and 4.497±0.542 U/mg to 6.28±1.57 U/mg respectively in U. urens, while in U. dioica the catalase and ascorbate peroxidase enzyme specific activities range from 0.49±0.015 U/mg to 0.583±0.0318 U/mg, respectively. The conducted study indicated the better potential of antioxidant activity found in U. urens than in U. dioica.