Utilizing the antidermatophytic potential of aromatic essential oils and their major constituents against clinically relevant dermatophytes

Abstract

Dermatophytosis is a common fungal infection of keratinized tissues (skin, hair, nails) caused by dermatophyte fungi. Conventional treatments rely on synthetic antifungals that can be costly, slow-acting, and prone to resistance or side effects. This has spurred interest in natural antifungal agents such as essential oils (EOs) from aromatic plants. Seven EOs from Origanum syriacum , Aloysia citrodora , Chiliadenus iphionoides , Salvia officinalis , S. fruticosa , Clinopodium serpyllifolium , and Rosmarinus officinalis were hydrodistilled and analyzed by gas chromatography–mass spectrometry (GC‒MS). Their antifungal efficacy against Microsporum canis , Trichophyton rubrum , T. mentagrophytes , and Epidermophyton floccosum was evaluated using poisoned-food assay (EO-amended agar). Additionally, minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) were determined via standard broth dilution methods. A.citrodora and O. syriacum essential oils completely inhibited all tested dermatophytes at 0.5 µL mL⁻¹ and exhibited the lowest MIC and MFC values between 0.06 and 0.25 µL mL⁻¹, indicating their potent fungicidal effects. The efficacy of these EOs is likely attributed to high levels of thymol and carvacrol in O. syriacum and citral in A. citrodora . C. iphionoides EO had strong but variable inhibition across the dermatophytes. Other oils showed moderate to low effects. Certain essential oils, particularly those rich in phenolic monoterpenes or citral, demonstrated significant antidermatophytic activity. The strong efficacy of O. syriacum and A. citrodora oils highlights their potential as natural antifungal agents. These findings support further development of EO-based treatments for dermatophytosis, which could serve as safer, plant-derived alternatives or complements to conventional antifungal therapies.