Romanian Society of Pharmaceutical Sciences

« Back to Farmacia Journal 4/2022

SYNERGISTIC INTERACTION BETWEEN LAMIACEAE ESSENTIAL OILS AND ANTIFUNGAL DRUGS AGAINST CANDIDA ALBICANS ATCC 10231

NELI ERMENLIEVA 1, EMILIYA GEORGIEVA 2, SILVIYA MIHAYLOVA 3*, SYLVIA STAMOVA 4, KRASIMIRA LALEVA 5, GABRIELA TSANKOVA 1, ANTOANETA TSVETKOVA 3

1Department of Microbiology and Virusology, Medical University of Varna, Bulgaria
2Training Sector “Medical Laboratory Assistant”, Medical College-Varna, Medical University of Varna, Bulgaria
3Training Sector “Assistant Pharmacist”, Medical College-Varna, Medical University of Varna, Bulgaria
4Department of Pharmaceutical Chemistry, Pharmacy Faculty, Medical University of Varna, Bulgaria
5Department of Social Medicine and Health Care Organization, Medical University of Varna, Bulgaria

Download Full Article PDF

Several Candida species are part of the normal human microbiota. One of the main characteristics of Candida is its ability to form highly drug tolerance biofilms in the human host. The antifungal therapeutic options are still limited to only a few drug classes, none of which fulfils all desired expectations. Systemic Candida infections demonstrate the advantages of combined therapies carried out with combinations of at least two different antifungal drugs, or/and combinations with natural antifungal agents such as essential oils (EOs), peptide molecules etc. In this work we evaluated the antifungal effect of thyme and oregano essential oils against C. albicans ATCC10231 and their potential synergistic interactions with frequently used antifungal agents – nystatin and fluconazole. Synergic interactions between nystatin and fluconazole and EOs were determined by the checkerboard microtiter assay. The results of the study showed that fluconazole has a synergistic effect with Thymus vulgaris EO in combination with 9.37 μg/mL antifungal and 2 μg/mL essential oil, respectively (FIC index values 0.49). In combination with other concentrations of antimicrobial agents, the effect is additive or interfering. Fluconazole did not show a synergistic interaction with oregano EO at any of the combinations in different concentrations of antimicrobial agents (FIC index values 0.75). The MIC of fluconazole was again reported as 37.5 μg/mL and that of oregano EO - 16 μg/mL. Our findings showed an experimental occurrence of a synergistic interaction between and oregano EO and nystatin, thyme EO and nystatin and between fluconazole and Thymus vulgaris EO.