IN VITRO EVALUATION OF ANTIOXIDANT CAPACITY OF ALGERIAN ORIGANUM PLANT BY SPECTROPHOTOMETRICAL AND ELECTROCHEMICAL ASSAYS

Objective: The aim of the present study was to evaluate the antioxidant capacity and total phenolic of ethanolic extracts of two plants; Origanummajorana and Origanumvulgare . Methods: Total phenolic was estimated by the Folin-Ciocalteu method. The antioxidant capacity was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method forspectrophotometrical technique and cyclic voltammetry for electrochemical assay. Results: According to the results leaves extracts have very important values for polyphenols (266.86 mg GAE/g and 194.78 mg GAE/g) and high antioxidant activity; DPPH (IC 50 = 1.37 mg/L and IC 50 = 1.53 mg/L) for species majorana, and vulgare respectively. The antioxidant capacity of two species of Origanum was measured using ascorbic acid equivalent antioxidant capacity assays. The O. majorana extract showed the highest antioxidant capacity (292.97mg/g) followed by O. vulgare extract (163.64mg/g). Conclusion: The results show that the antioxidant capacity expressed in terms of ascorbic acid equivalent antioxidant capacity obtained from electrochemical experiments (cyclic voltammetry) is higher than that obtained from spectrophotometrical experiments using DPPH. This outcome can be attributed to the overestimation of the total polyphenolic contents due to the interferences of other non-phenolic species.

• Origanum majorana
• oregano
• antioxidant capacity
• total phenolic content
• polyphenols
• DPPH radical scavenging
• cyclic voltammetry
• ethanolic plant extract
• leaf extract
• method comparison

• Phytochemicals and Antioxidant Activities
• Essential Oils and Antimicrobial Activity
• Medicinal Plant Research
• Origanum majorana
• oregano
• antioxidant capacity
• total phenolic content
• polyphenols
• DPPH radical scavenging
• cyclic voltammetry
• ethanolic plant extract
• Biochemistry
• Food Science
• Plant Science
• Medicine
• Agricultural and Biological Sciences