Antifungal Activity of Mentha × piperita L. Essential Oil Against Trichophyton mentagrophytes

Dermatophytosis, a superficial fungal infection caused by dermatophytes such as Trichophyton mentagrophytes, has become increasingly difficult to manage due to rising resistance to synthetic antifungals like terbinafine. This study evaluates the potential of peppermint (Mentha × piperita L.) essential oil, rich in menthol, as a natural antifungal alternative. Peppermint oil was extracted through water distillation and tested at concentrations of 25%, 12.5%, 6.25%, 3.125%, 1.562%, 0.781%, 0.390%, and 0.195% to evaluate its inhibitory effects on three different strains of T. mentagrophytes. The Minimum Inhibitory Concentration (MIC) was determined using the microdilution method according to CLSI M38 guidelines. Antifungal activity was assessed based on medium turbidity, with itraconazole serving as a positive control. The findings revealed that peppermint oil at a concentration of 0.78125% suppressed the growth of two T. mentagrophytes variants, whereas a concentration of 12.5% was required to inhibit the third variant. These results suggest that peppermint essential oil could serve as a natural antifungal agent against T. mentagrophytes, justifying additional research as an alternative to synthetic therapies.