Mechanistic Insights into Honey-Mediated Antibacterial Activity Against Enterobacteriaceae: A Multifaceted Approach...

The escalating crisis of antibiotic resistance necessitates exploration of alternative antimicrobial agents. This study investigates the multifaceted antibacterial mechanisms of Egyptian honey against clinically significant Enterobacteriaceae. We employed an integrated experimental approach that combined microbiological assays, biochemical analyses, and bioinformatics to elucidate the mode of action of honey. Results demonstrated potent antibacterial activity with minimum inhibitory concentrations ranging from 12.5% to 25% (v/v) against multidrug-resistant Escherichia coli, Klebsiella pneumoniae, and Salmonella typhimurium. Mechanistic studies revealed that honey induces severe membrane perturbation, evidenced by 78.3% potassium ion leakage and 82.6% protein leakage at sub-inhibitory concentrations. The honey exhibited remarkable antioxidant capacity (IC₅₀ = 18.42 mg/mL, TBARS lipid peroxidation assay) and a high phenolic content (287.3 ± 12.4 mg GAE/100 g), correlating with its membrane‑destabilizing activity. Furthermore, honey demonstrated prebiotic effects, enhancing the growth of Lactobacillus and Bifidobacterium by 45-52%, while simultaneously inhibiting Quorum‑sensing-related redox activity by 64-71%. Protein synthesis assays revealed suppression of ribosomal protein expression by 67.4%, as determined by radiolabeled methionine incorporation and SDS-PAGE. Gene ontology enrichment analysis identified 143 downregulated genes associated with membrane transport, cell wall biosynthesis, and biofilm formation. These findings establish honey as a multitarget antimicrobial agent operating through synergistic perturbation of membrane integrity, metabolic inhibition, and virulence attenuation, offering promising therapeutic potential against resistant Enterobacteriaceae.