Évaluation biologique d'une plante médicinale de la région de l'oued

Abstract

Origanum majorana L. is known as marjoram, it is a medicinal plant very rich in essential oils and polyphenols. Widespread in European and North African countries. This species used in traditional medicine because of these many therapeutic characteristics. The objective of this work is the phytochemical study, the evaluation of the antioxidant and antibacterial activity of the extract of an Algerian medicinal plant Origanum majorana L. harvested from the region of OUED SOUF. The aqueous and methanolic extracts were obtained by maceration using distilled water and methanol as solvent and essential oils by hydrodistillation of the leaves of Origanum majorana L. The yield was obtained 24% for the methanolic extract, 20% for aqueous extract and 0.51% for essential oils. The total polyphenols content in the different extracts is determined by the Folin-Ciocalteu reagent method (FCR). The polyphenol contents for the aqueous and methanoic extracts are respectively 123.5±7.75 and 134.4±8.43mgEAG/g EXT. The total flavonoid content contained in the extracts is carried out by the aluminum trichloride method (AlCl₃), the results show that the aqueous and methanolic extracts respectively are 19.77±1.39 and 26.3±0.94 mg QE / g extract. Antioxidant activity was assessed using the DPPH method. The CI₅₀ was estimated to be 4.9±0.416 and 7.099±0.149 and 7.61±0.134 μg/ml for methanolic and aqueous extract and essential oils. The antibacterial activity of extracts of Origanum majorana L. by the method of diffusion of discs on solid agar media, Mueller-Hinton for bacteria (E. coli, Listeria, S. aureus and Pseudomonas aeruginosa) the power of aqueous and methanolic extracts is zero. The oil exerted considerable inhibitory powers against several of the bacteria; it was found that HE has a bacteriostatic effect against S. aureus (Inhibits the spread of bacteria) and a bactericidal effect against E. coli (kills bacteria).