Chilean Honey as Alternative Antibacterial: In Vitro Activity Against Multidrug-Resistant Canine Bacterial Pathogens

Area of Science:

• Veterinary Medicine
• Microbiology
• Natural Products Chemistry

Background:

• Antimicrobial resistance (AMR) is a growing concern in veterinary medicine, especially for bacterial skin infections in dogs.
• Natural products like honey offer potential alternatives to conventional antibiotics.
• Multidrug-resistant (MDR) bacterial infections pose a significant threat to canine health.

Purpose of the Study:

• To evaluate the antimicrobial activity of methanolic honey extracts against MDR canine bacterial isolates.
• To correlate antimicrobial potency with the bioactive compound content (phenolics, flavonoids) and antioxidant capacity of different honey types.
• To explore the influence of season and floral origin on honey's antimicrobial properties.

Main Methods:

• Methanolic extracts from four Central Chile honey types were tested.
• Minimum Inhibitory Concentration (MIC) determined antimicrobial activity against Enterococcus faecium, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Pasteurella multocida, and Enterobacter cloacae.
• Phenolic, flavonoid content, and antioxidant capacity (FRAP) were quantified; seasonal and apiary variations were analyzed.

Main Results:

• All honey extracts demonstrated antimicrobial activity against tested MDR bacteria.
• E. coli, E. faecium, and S. aureus were most susceptible (MIC 3.13% w/v).
• Gram-negative bacteria (P. aeruginosa, P. multocida, E. cloacae) required higher concentrations (MIC 12.5% w/v).
• Apiary 2 honey exhibited higher phenolic and flavonoid content in summer.
• Antioxidant capacity did not show significant differences across samples.

Conclusions:

• Honey extracts possess significant antimicrobial properties against MDR bacteria relevant to canine infections.
• The antimicrobial efficacy of honey is linked to its bioactive composition, influenced by season and floral source.
• Honey represents a promising, sustainable alternative to antibiotics in veterinary medicine, aligning with the One Health approach.