Solubilization in vitro of tea tree oil and first results of antifungal effect in onychomycosis

Abstract

Introduction: Onychomycosis is the main cause of nail alteration. Hepatotoxicity, interference and low adherence to pharmacological treatment are associated. Therefore, our objective was to assess the in vitro effectiveness of tea tree essential oil (less harmful) against main causative agents of these infections.

Material and methods: Thrichophyton rubrum and Thrichophyton mentagrophytes were isolated and inoculated at a concentration of 3 × 10⁵ CFU/mL in potato agar dextrose and tea tree essential oil at different concentrations to assess its effect by counting colony forming units and radial growth.

Results: Trichophyton rubrum growth inhibition was obtained at concentrations higher than 0.04% of the essential tea tree oil (p = 0.004). In the case of Thrichophyton mentagrophytes, inhibition was obtained at 0.02% (p = 0.017), and even complete inhibition at a final concentration of the oil at 0.07%.

Conclusions: Tea tree essential oil inhibits the in vitro growth of the fungus and may be a less harmful alternative to the onychomycosis treatment.

Keywords: Melaleuca alternifolia; Onicomicosis; Onychomycosis; Tea tree; Trichophyton mentagrophytes; Trichophyton rubrum; Árbol de té.