Utilization of Lichen Metabolites as Natural Antifungal Drug against Dermatophytosis

Abstract

During antifungal screening the aqueous extract of some lichens, Peltegera paraetaxtala tested at different concentrations against human pathogenic fungi (dermatophytes), Epidermophyton floccosum, Microsporum audouinii, M. nanum, M. canis, M. gypseum, Trichophyton mentagrophytes, T. rubrum, T. violaceum and T. tonsurance by MSGIT of Shahi et al, (1997). The lichen Peltegera paraetaxtala was found effective at 40 µl/ml at which extract showed fungistatic action, while the minimum fungicidal concentrations (MCCs) were found to be 60 µl/ml against human pathogenic fungi. The extract at MCCs showed heavy doses of inoculum potential and its toxicity did not expire even upto 24 months of storage. Moreover, extract did not exhibit any adverse effect on mammalian skin up to 10% concentration. Further, the extract of Peltegera paraetaxtala was formulated in the form of ointment and trialed clinicaly in MLN Medical college, Allahabad. 30 patients were selected, showing positive potassium hydroxide (KOH) results at the start of the trial. Patients were diagnosed as either tinea corporis, tinea cruris or tinea pedis. All patients were treated with ointment twice in a day for 3 week. At the end of medication, 35.0% of patients’ recovered complete cure, 40.0% showed significant improvement from the disease. No KOH negative cases of relapse were observed when patients were reexamined after two month following the end of treatment thereby, denoting the absence of relapse. The ointment was found cost effective, had long shelf life and absence of any adverse effects. Thus, the essential oil could be used as potential sources of antidermatophytic agent after undergoing successful multicentre clinical trial.