Assessment of the synergistic effects of essential oils and antibiotics on antibiotic-resistant food-borne disease bacteria in Burkina Faso

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Résumé

Background: Antibiotic resistance is a major public health concern in Burkina Faso, highlighting the urgent need for alternative therapeutic strategies. This study aimed to
evaluate the in vitro synergistic effects of essential oils extracted from two medicinal plants in Burkina Faso, Hyptis suaveolens and Laggera aurita, in combination with ampicillin,
amoxicillin, amoxicillin + clavulanic acid, and colistin against antibiotic-resistant bacteria. Methods: The study assessed the antimicrobial activity of essential oils and antibiotics
and that of their combination against seven bacterial strains: Staphylococcus aureus ATCC 2523, Enterococcus faecalis 0366 V, Escherichia coli ATCC 25922, Salmonella typhi
SKN 1152, Salmonella paratyphi SKN 601, Yersinia enterocolitica 0938 V, Pseudomonas aeruginosa ATCC 9027. The agar diffusion well, microdilution, checkerboard, and kill
curve methods were employed. Results: L. aurita essential oil showed a mean inhibition diameter of 37.83 ± 1.24 mm, with MIC values ranging from 0.59 to 7.97 mg/mL. H.
suaveolens essential oil showed a mean inhibition diameter of 14.67 ± 0.40 mm, with MIC values ranging from 2.02 to 8.11 mg/mL. The combination of L. aurita and H. suaveolens
essential oils with antibiotics exhibited synergistic effects in 64.7% and 60% of cases, respectively. The kill curve assay demonstrated the shortest bacterial killing time at 4 hours and the longest at 16 hours, depending on the synergistic combination. Conclusion: The study suggests that combining essential oils with antibiotics could serve as an alternative
treatment for multidrug-resistant infections. Further investigations, including clinical trials, are necessary to confirm the therapeutic potential of these combinations.

Mots-clés

Antibiotics bacterial resistance essential oils synergy multidrug-resistant infections.