Formulation and evaluation of an antifungal gel for tinea corporis by using Achyranthes aspera leaf extract

Achyranthes aspera, a medicinal plant traditionally used in Sri Lanka, exhibits antidermatophytic properties. This study aimed to formulate and evaluate topical herbal gels incorporating A. aspera leaf extract for activity against Trichophyton rubrum and Trichophyton mentagrophytes. Gels were formulated with different concentrations of A. aspera leaf extract: 1% (A), 3% (B), and 5% (C). Physicochemical properties, including pH, viscosity, and spreadability, and antifungal activity against clinical isolates of T. rubrum and T. mentagrophytes were evaluated using agar well diffusion, with ketoconazole as a positive control and 5% DMSO as a negative control. Stability was monitored over 15 days by assessing changes in physicochemical properties. All formulations were green, homogeneous, opaque, and smooth, with a semi-solid consistency; they maintained a skin-compatible pH (6.5–6.9) and stable physicochemical characteristics throughout the 15 days. All gels exhibited antifungal activity, with formulation C displaying the highest potency, producing zones of inhibition of 23.33 mm against T. rubrum and 24.33 mm against T. mentagrophytes. In comparison, the positive control yielded inhibition zones of 25.66 mm and 29.00 mm, respectively. In conclusion, the A. aspera leaf extract gel demonstrates moderate antifungal activity, particularly the 5% formulation, suggesting its potential as an alternative topical therapy for Tinea corporis. Further preclinical, clinical, and long-term stability studies are warranted.