Background: Antibiotic resistance is today one of the most serious threats to global health, food security and development. A growing number of infections, treatment becomes more difficult, if not impossible, because of the loss of antibiotic efficacy.
Objectives: In the present investigation, chemical composition of essential oils of Ammoides verticillata and Satureja candidissima and their synergistic effects antimicrobial activities were investigated.
Methods: The chemical composition of the essential oil was analyzed by Gas Chromatography (GC) and Gas Chromatography Mass Spectroscopy (GC/MS). The antimicrobial activity of the essential oils was investigated using dilution-agar method against nine bacterial strains three Gram-negative Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853) and Salmonella typhi (ATCC 14028), and six Gram-positive: Staphylococcus aureus (ATCC 43300,) Clostridium sporogenes (ATCC 19404), Bacillus subtilis (ATCC 6633), Enterococcus faecalis (ATCC 7314), Lactobacillus rhamnosus (ATCC 53103) and Bacillus cereus (ATCC 14579).
Results: The essential oil of A. verticillata was characterized principal by carvacrol (44,3%), limonene (19,3%) and p-cymene (19,2%). The constituents identified of S. candidissima essential oil were principally oxygenated monoterpenes represented by pulegone (70,4%). The essential oil of A. verticillata had a good antimicrobial activity against four bacterial strains (Escherichia coli, Salmonella typhi, Lactobacillus rhamnosus and Bacillus cereus) with MIC and MBC values between 0.2-0.4 μl/ml and 0.2-6.2 μl/ml, respectively. While, S. candidissima essential oil had moderated antimicrobial activities against all strains with MIC and MBC values between 1.5-6.2 μl/ml and 6.2-12.5 μl/ml, respectively. The results of antimicrobial activity of essential oils blend presented higher antimicrobial activity against all tested bacteria with MIC and MBC values between 0.3-1.5 μl/ml and 0.4-6.2 μl/ml, respectively.
Conclusion: These results, therefore, represent a basis for further studies that could lead to the development of a new treatment based on combination of these essential oils against the most resistant microbial strains.