Investigation of therapeutic potential in murine cutaneous leishmaniasis and antibacterial using biosynthesized silver nanoparticles using extract of Crocus sativus petals

Leishmaniasis, classified as a neglected tropical disease (NTD), is a parasitic infection caused by protozoa and transmitted through vectors. It is a widespread condition found in over 100 countries, known for its destructive nature. Consequently, there is an increasing need to establish novel approaches for combating leishmaniasis and developing effective strategies to combat the disease. In this study, we report an eco-friendly, cost-effective, and biocompatible process for the preparation of silver nanoparticles (AgNPs) using aqueous extract of Crocus sativus petals and their antibacterial and anti-leishmanial activities. Characterization of biosynthesized AgNPs was conducted by UV-vis spectroscopy, TEM, FTIR, DLS, and FESEM spectroscopy. TEM and FESEM images revealed the existence of spherical/oval morphology with a size range of 30–70 nm. Additionally, functional groups associated with the extract were observed, indicating their involvement in the stabilization and coating of the biologically fabricated AgNPs. Furthermore, the AgNPs were confirmed through the observation of a surface plasmon response (SPR) with a peak wavelength of approximately 423 nm. This was accompanied by noticeable color transformation from transparent to brown, providing further evidence of the successful formation of AgNPs. Biosynthesized AgNPs from saffron wastages showed promising anti-leishmanial and antibacterial activities. The AgNPs displayed a zone of inhibition of 23 mm against Staphylococcus aureus and 10 mm against Pseudomonas aeruginosa, indicating their potential antibacterial performance against these microorganisms. The application of an ointment containing quercetin/saffron-capped silver nanoparticles on mice infected with Leishmania major resulted in promising outcomes. The treated group exhibited a reduction in inflammatory responses and an increase in fibroblast activity compared to the untreated group. These results indicate the potential of this compound to alleviate inflammation and promote the growth of fibroblasts, which are beneficial for wound healing and tissue repair. In conclusion, the utilization of biogenically synthesized silver nanoparticles derived from saffron holds promise as an alternative therapeutic approach for treating cutaneous leishmaniasis.