Antifungal activity of green sulfur nanoparticles synthesized using Catharanthus roseus extract against Microsporum canis

Elemental sulfur has been used for a long time to treat superficial mycoses in both medical and veterinary practices, but effective treatment requires high concentrations of sulfur. Encapsulation of sulfur in nanoparticles can potentially allow the delivery of high concentrations of sulfur to infections. Sulfur nanoparticles were synthesized from Catharanthus roseus extract and sodium sulfide at various pH conditions (4, 6, and 7). Particle identification and characterizations were performed by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and dynamic light scattering analysis. Broth microdilution and time-kill assays were used to determine the antifungal effect against Microsporum canis DMST29297. The X-RD analysis showed that the fine yellow powder of sulfur nanoparticles contained alpha-orthorhombic sulfur and SEM showed a uniform distribution and similarity in size of almost spherical particles. Sulfur nanoparticles synthesized with C. roseus extract at pH 7 had the smallest average size (480 +/- 39.6 nm) and highest antifungal activity (MIC 1.56 mg/ml). The fungicidal activity of the sulfur nanoparticles was time dependent, eliminating M. canis DMST29297 only after 24 hours. Green sulfur nanoparticles synthesized with C. roseus extract have potential to be developed as an antifungal agent against M. canis. However, increased antifungal activity should be further developed.