Etude des effets antibactériens de l’extrait hydroéthanolique de Salvadora persica sur quelques germes responsables des infections nosocomiales.

Abstract

This study focused on the antibacterial effect of hydro-ethanolic extract of Salvadora persica on the growth of certain bacteria of clinical reference and respensable nosocomial infections namely: Staphylococcus.aureus, Escherichia.coli and Pseudomonas.aeruginosa . The experimental extract was obtained by maceration of a stem intake of the plant under study for 6 hours in an 80/20 aqueous ethanol solution (v/v/ethanol/water) followed by vacuum evaporation. This hydroethanolic extract was concentrated at 0, 20, 40, 60, 80 and 100%. The following measures and controls were tested on the pathogenic bacteria studied (diameter and inhibition rate, growth test, Minimum Inhibitory Concentration and Minimum Bactericidal Concentration). The study revealed that the pure hydro-ethanolic extract of Miswak (Salvadora persica) has a strong antimicrobial activity against reference and clinical bacteria studied. Compared to gentamycin, this extract recorded varying inhibition rates from 49.35 to 97.06% in Pseudomonas aeruginosa, from 55.62 to 69.44 in Escherichia coli and from 55.32 to 105% in Staphylococcus aureus. The minimum MIC inhibitory concentrations were obtained in clinical strains and references to extract preparations of 60 and 40% in Escherichia coli, 80 and 40% in Pseudomonas aeruginosa and 60 and 80% in Staphylococcus aureus, respectively. In contrast, CMB Bactericidal Minimum Concentrations were observed successively at 60 and 40 in Escherichia coli, 80 and 40% in Pseudomonas aeruginosa and 60 and 40% in Staphylococcus aureus. Phenolic extracts are found to exert a bactericidal type action vis-à-vis the studied germs.