Antimicrobial resistance motivates antibacterial agents with multi-target mechanisms. We evaluated Moroccan rosemary essential oil (ROEO) against four pathogens ( Escherichia coli , Citrobacter freundii , Staphylococcus aureus , Enterococcus faecalis ) by disk diffusion and broth microdilution. ROEO inhibited all strains (zones 11.3–21.0 mm); activity was bactericidal for E. faecalis (MBC/MIC = 2.0) and bacteriostatic for others (MBC/MIC > 4). Bioassay-guided silica chromatography, using E. faecalis as the pre-specified indicator, localised activity to a polar fraction (F8; 18.5% of the oil; 14.0 ± 1.71 mm). GC–MS showed F8 was enriched in oxygenated monoterpenes (97.45%): myrtenol, verbenone, p-cymen-8-ol, γ-terpinen-7-al, carvone, β-thujone. Docking (AutoDock Vina) predicted binding of major constituents to essential enzymes (tyrosyl-tRNA synthetase, L-methionine γ-lyase, DNA gyrase B, and NAD⁺-dependent DNA ligase); native-ligand redocking reproduced crystallographic poses (RMSD ≤ 2.0 Å). In silico ADMET supported drug-like properties with high intestinal absorption and class-typical CNS-penetration and skin-sensitisation alerts. ROEO’s antibacterial profile is underpinned by an oxygenated-monoterpene fraction and yields testable hypotheses for enzyme validation, synergy studies, and in vivo efficacy and safety.
Lahlou et al. (Mon,) studied this question.