Thyme essential oil as an antimicrobial and biofilm inhibitory agent against abscesses with P. mirabilis Infections

Introduction: Abscesses are high density microbial infections of which biofilm formation plays a crucial role on their recurrence and chronicity. In this study, the authors aim was to determine biofilm formations of three different abscess cultures and to investigate antimicrobial and antibiofilm effects of clary sage, clove and thyme oils against the identified bacterial strain isolated from the highest biofilm forming abscess culture.Methods: This in vitro study consisted of skin, breast and perianal abscess materials of 3 different patients. "Papanicolaou" staining and "Periodic Acid Schiff" staining methods were performed for cytological examination. Biofilm formation and biofilm inhibition tests were determined by "Crystal Violet Binding" assay and Minimum Inhibitory Concentrations (MIC) of the selected essential oils were calculated by "Micro-Dilution" method.Results: Escherichia coli, Enterobacter aerogenes and Proteus mirabilis strains were isolated from perianal, skin and breast abscesses respectively. The bacterial strain that exists in the highest biofilm forming abscess culture was identified as P. mirabilis. P. mirabilis strain was found as resistant to Ampicillin and Trimethoprim/Sulfamethoxazole. Clary sage oil was unable to inhibit growth of P. mirabilis strain at the highest concentration tested (500 mu L/mL). However, clove and thyme oils inhibited biofilm formation of P. mirabilis strain in addition to inhibiting its growth at very low concentrations (1.95 mu L/mL and 0.98 mu L/mL respectively).Conclusion: Thyme oil having the lowest inhibitory concentration and the highest antibiofilm effect has a good potential to be used as an antimicrobial and antibiofilm agent for the management of abscesses with P. mirabilis infections.