Activity of Thymus caespititius essential oil and α-terpineol against yeasts and filamentous fungi

The composition and antifungal activity of the essential oil (EO) of Thymus caespititius and alpha-terpineol against yeast, dermatophyte, and Aspergillus strains, responsible for human infections and food contamination, were studied. The cytoxicity and the effect of EO on the yeast-mycelium conversion in Candida albicans were also evaluated. Analyses by GC and GC/MS showed high amounts of alpha-terpineol (35.7%), unusual in Thymus species. T. caespititius EO has a broad-spectrum antifungal activity that may be due to alpha-terpineol but also to a synergistic effect of other components. The dimorphic transition in C albicans, an important virulence factor, was influenced by the EO and alpha-terpineol. Filamentation was almost completely inhibited at concentrations sixteen times lower than the minimum inhibitory concentration. According to FDA, many EOs and individual components are classified as GRAS (generally regarded as safe). The low cytotoxicity observed for T. caespititius and alpha-terpineol and their antifungal activity are compatible with the development of new phytopharmaceuticals for mycosis treatment and the use as food preservatives. (C) 2014 Elsevier B.V. All rights reserved.