L’effet antibactérien des huiles essentielles des citrus (limonum et sinensis) sur différentes souches Escherichia coli, Pseudomonas aeruginosa et Staphylococcus aureus

Abstract

In order to select new plant products with pharmacological activities and potentials, the present study focuses on the evaluation of the antibacterial effects of citrus essential oils against certain pathogenic strains. The objective of our work is to evaluate the antibacterial effect of essential oils extracted from the leaves of two Citrus species. C. limonum (lemon) and C. sinensis (orange) growing in the Wilaya of Mostaganem. To do this, we first extracted the essential oils from the cirtus by steam distillation; the yield was very low, 0.20% for C. limonum and 0.12% for C. sinensis. The antibacterial activity was evaluated by inhibition on MH agar on three strains (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa). The essential oil of C.limonum (lemon) revealed an interesting activity revealed by inhibition zones between 7 and 24 mm comparable to that due to C. sinensis (orange) with inhibition zones varying between 7 and 23 mm. The dilutions were characterised by a lower zone of inhibition. Among all the bacteria tested, Escherichia coli, Staphylococcus aureus showed the highest sensitivity. The study of the antimicrobial activity of citrus essential oils was determined by their bactericidal or inhibitory effects in our in vitro study, and leads us to conclude that, whether pure or diluted, they present excellent alternatives to synthetic antibiotics to combat bacterial infestations caused by E. coli and S. aureus, which will allow us to face the problems of antibiotic resistance and the dramatic side effects of the excessive consumption of synthetic antibiotics.