In Vitro Susceptibility of Sporothrix brasiliensis to Essential Oils of Lamiaceae Family.

This study evaluated the chemical, cytotoxic and anti-Sporothrix brasiliensis properties of commercial essential oils of rosemary (Rosmarinus officinalis L.), oregano (Origanum vulgare L.) and marjoram (Origanum majorana L.). Chemical composition of the oils was identified through gas chromatography with flame ionization detector, and cytotoxicity was performed through MTT assay in VERO cell line. Anti-S. brasiliensis activity was performed according to the CLSI M38-A2 guidelines using isolates obtained from cats and dogs. The major compounds found were carvacrol in the oregano oil (73.9 %) and 1,8-cineole in rosemary and marjoram oils (49.4 and 20.9 %, respectively). All S. brasiliensis isolates were susceptible to the plant oils, including itraconazole-resistant ones. Marjoram and rosemary oils showed MIC90 of 0.56 and 1.12 mg ml-1, and MFC90 of 4.5 and 9 mg ml-1, respectively. For oregano oil, a strong antifungal activity was observed with MIC90 and MFC90 values ≤0.07 mg ml-1. The weakest cytotoxicity was observed for rosemary oil. Further studies should be undertaken to evaluate the safety and efficacy of these essential oils in sporotrichosis.