Phyto-fabrication and characterization of silver nanoparticles from Trachyspermum ammi (Ajwain) seeds and assessment of their antifungal activity

Abstract

The rising incidence of fungal infections combined with the emergence of resistance to existing antifungal drugs highlight the urgent need for novel, safe, and eco-friendly therapeutic options. Green nanotechnology provides a sustainable way to build such alternatives. The present study reports an inexpensive, environmentally acceptable, and non-toxic green method for the biosynthesis of silver nanoparticles (AgNPs) utilizing aqueous seed extract of Trachyspermum ammi (TA). The biosynthesized T. ammiAgNPs (TA-AgNPs) were characterized using several sophisticated analytical techniques, and their antifungal efficacy was studied. The formation of AgNPs was visually represented by a shift from a light brown to a dark or red-brown color and confirmed by the surface plasmon resonance band at 419 nm. The particle size, polydispersity index, and zeta potential of AgNPs were found to be 101.5 nm, 0.270, and – 41.7 mV respectively. Studies using a transmission electron microscope (TEM), energy dispersive X-ray spectroscopy (EDX), selected area electron diffraction (SAED) spectrum, and X-ray diffraction (XRD) confirmed that the biosynthesized AgNPs were spherical, contained elemental silver, and had a crystalline structure. The TA-AgNPs showed distinctive antioxidant potential, biocompatibility, and promising antifungal activity against Candida species and Aspergillus niger. The disc diffusion method demonstrated that TA-AgNP's gel had more pronounced antifungal activity than the commercially available Silverex^™ ionic (silver nitrate 0.2% w/w) gel. In conclusion, the present work showed that TA seed extract mediated AgNPs gel could be the potential therapeutic agent for human fungal infections.