Chemical composition and antimycotic potential of basil, rosemary, clove and cinnamon essential oils against Trichophyton rubrum and Trichophyton mentagrophytes

Onychomycosis is a disease caused by fungi that affects the nails whose incidence is becoming increasingly frequent. The present study aimed the evaluation of the antifungal activity of essential oils from clove (Syzygium aromaticum), Chinese cinnamon (Cinnamomum cassia), rosemary (Rosmarinus officinalis) and basil (Ocimum basilicum), against the most prevalent dermatophytes implicated in onychomycosis: Trichophyton rubrum and Trichophyton mentagrophytes. The chemical composition of the oils was determined by GC-MS. The volatile oil of clove and Chinese cinnamon and basil presented, respectively, the phenylpropanoids eugenol (80.2%), E-cinnamaldehyde (99.4%) and methyl chavicol (68.81%) as the main components. The volatile oil of rosemary exhibited 1,8-cineole and camphor as the major compounds, representing 47% and 15% of the total content, respectively. The results obtained in broth microdilution tests indicate that basil oil presented the best antifungal potential against the tested strains of Trichophyton rubrum and Trichophyton mentagrophytes at concentrations that ranged from 8 mg/mL to 2 mg/mL. These findings point to the potential prospecting of Ocimum basilicum essential oil as a promising source of natural antimycotics to be subjected for further investigations.