Abstract:
The antimicrobial activity of honey is well documented and results from a complex interplay of physicochemical and
biological factors such as low pH, high sugar content, enzymatic antioxidants, phenolic compounds, and microbial
metabolites. This study evaluated the antimicrobial and antibiofilm properties of 14 honey varieties from Alba County,
Romania, against multidrug-resistant Escherichia coli and Staphylococcus aureus strains isolated from wound
secretions. Minimum inhibitory concentration (MIC) was determined by broth microdilution, while biofilm inhibition
(PI%) was assessed using the crystal violet microplate assay. MIC values ranged from 8% to 30% (v/v), depending on
honey type and bacterial strain. The most effective samples (MIC ≤ 15%) included mountain, forest, raspberry, fir, and
polyfloral honeys, while acacia, linden, rape, heather, and dandelion honeys showed lower efficacy (MIC ≥ 25%).
Biofilm inhibition rates varied between 55% and 92%, with the highest activity observed in mountains, forest, and
polyfloral honeys (PI% ≥ 85%). Statistical analysis revealed significant positive correlations between polyphenol
content and antibiofilm activity (r=0.73 for E. coli; r=0.65 for S. aureus, p<0.01). These findings highlight the
therapeutic potential of selected honey varieties as natural complementary agents in the prevention and management of
multidrug-resistant bacterial infections.
