Antibacterial Activity and Antibiofilm of Essential Oils of Clove and Thyme Against Clinical Isolates of Multidrug-Resistant Acinetobacter Baumannii Associated with Nosocomial Infections

Author(s): Nihal EZZARIGA, Oumaima ZOUHARI, Amal RHARS, Asmaa WAKRIM, Mohamed AGHROUCH, Zohra LEMKHENTE

In recent years, Acinetobacter baumannii infections have drawn significant medical interest. This opportunistic pathogen often causes nosocomial infections. The antibiotic resistance in A. baumannii biofilms complicates treatments, necessitating new control strategies. This study evaluated the antibacterial and antibiofilm activities of clove and thyme essential oils. Seven multidrug-resistant A. baumannii strains, including six clinical isolates and one reference strain (ATCC 19606), were tested. Essential oils demonstrated strong antibacterial effects, with inhibitory zone diameters (IZDs) of 14-31 mm for Syzygium aromaticum and 17-39 mm for Thymus vulgaris. MIC values ranged from 0.78 to 12.5µl/ml for S. aromaticum and 0.19 to 12.5µl/ml for T. vulgaris. All strains formed biofilms, and the oils effectively inhibited biofilm formation. These results suggest that clove and thyme oils could offer new strategies for managing nosocomial infections.