Étude phyto-chimique et microbiologique de l’huile essentielle de LIPPIA CITRIODORA

Abstract

Lippia citriodora, known in Arabic as (Louisa), is an aromatic medicinal plant belonging to the Verbenaceae family, one of the most important families in Algerian flora. Our work has focused on the physicochemical study and biological activities of lemon verbena essential oil, carried out in the laboratory of the national agricultural research institute laboratory in setif. The study of the chemical composition of essential oil extracted by the CGMS method was carried out in the Toxicology laboratory of the Setif pharmacy department during the 2022-2023 academic year. The essential oil obtained by a Clevenger-type hydrodistiller is yellow in color, with a pleasant lemony odor and an average yield of (1.31 ± 0.11%) of the plant. GC-MS analysis of the essential oil enabled us to identify 39 compounds representing 97.57% of the total oil, dominated by the presence of the major compounds: Limonene as the major constituent (30.99%), citral (14.29%), Neral (13.36%), Spathulenol (10.66%), Ar-curcumene (5.22%), which represented 74.52% of HE. The study of the antioxidant activity of essential oils by the DPPH method, showed the existence of significant antioxidant activity as they inhibited more than (80%) of the DPPH compared with standard BHT, and an IC50 of (64566.75 ± 348.02 µg /ml). Evaluation of antiinflammatory activity in Vitro by the HRBC red blood cell assay (human blood membrane stabilization procedure) shows that the essential oil possesses medium anti-inflammatory power, with a maximum hemolysis inhibition percentage of 52.61% and an IC50 of (875.1 ± 145.47 µg /ml). The aromatogram method enabled us to determine strong anti-bacterial activity of the oil against the Gram-positive bacterial strains examined: Bacillus ATCC6633 ATCC27853 and Staphylococcus Aureus ATCC25923 as well as against gram-negative bacteria: Escherichia Coli ATCC25922, Bacillus ATCC6633.