Mechanism of action of essential oil-antibiotic combinations on bacteria involved in foodborne toxin infections

Background. Bacterial resistance to antibiotics threatens public health in Burkina Faso. This calls for exploring alternative solutions alongside traditional methods. Objectives. To evaluate the efficacy of combined essential oils-antibiotic against antibiotic-resistant pathogens causing toxic infections in Burkina Faso. Methods. The methodological approach involved testing the combined effects of essential oils from two plants, Hyptis suaveolens and Laggera aurita with two antibiotics: amoxicillin plus clavulanic acid, and colistin, on pathogenic bacteria. The antibacterial properties of the essential oils were confirmed through MIC and MBC tests. The antibacterial mechanism was examined on bacteria such as Staphylococcus aureus ATCC 2523, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 9027, Enterococcus faecalis 0366 V, Bacillus cereus 0998 V and Yersinia enterocolitica 0938 V. The mechanism of action of the essential oil-antibiotic combination was examined by quantifying the released DNA. Results. The main results showed MIC values ranging from 9.57 mg/mL to 38.28 mg/mL for Hyptis suaveolens and from 1.69 mg/mL to 64.92 mg/mL for Laggera aurita. Of the 20 combinations essential oils-antibiotics tested on bacteria, 70% showed total synergy, 15% showed partial synergy and no synergy respectively. The DNA release rate was 93.76%, indicating a mechanism involving simultaneous damage to the peptidoglycan and plasma membrane. Conclusion. Essential oils and antibiotics combination could constitute an excellent mean against bacterial resistance to antibiotics. Keywords: Antibacterial mechanism; Antibiotics; Essential oils; Hyptis suaveolens; Laggera aurita; Combination action.