Antifungal activity of essential oils against azole-resistant and azole-susceptible Candida glabrata strains vaginal isolates

Candida glabrata is an opportunistic pathogen, associated with endocarditis, meningitis and disseminated disease and also with complicated vaginitis. Essential oils derived from aromatic plants are known in traditional medicine as antimicrobial agents and have antifungal properties. The aim of this work was to evaluate whether the twelve tested essential oils (tea tree, laurel, anise, basil, bergamot, lavender, mint, oregano, grapefruit, rosemary, winter savory and ginger) could have a transverse effect on C. glabrata sensitive strains but, above all, on strains resistant to the three main used azole antifungals (clotrimazole, fluconazole, itraconazole). For this reason, different strains of C. glabrata, vaginal isolated, were characterized (disk diffusion assay, MIC) with respect to their response to such antifungals. Electron microscopy analyses were performed to examine in depth cellular damages. Subsequently, we wanted to evaluate the effect of the oils also on human cells in order to estimate their potential cytotoxicity. Oregano and winter savory were the two most effective essential oils inducing: growth inhibition, cell damage of C. glabrata strains (both sensitive and resistant to azole antifungal drugs) and medium-high level of toxicity against human keratinocytes. The results of this work support the research for new alternatives or complementary therapies against vaginal candidiasis.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author