Investigating the antibacterial and antioxidant properties of silver nanoparticles synthesized by turmeric extracts

The aim of the study was to determine how to produce green silver nanoparticles (AgNPs) from silver precursors in an economical and environmentally responsible manner. In order to achieve the green synthesis of AgNPs using the aqueous extract of turmeric powder, plant biomaterials were employed as a capping and reducing agent. Energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) and ultraviolet-visible spectrophotometer was used to analyze AgNPs. The UV-vis spectrum's highest absorption was measured at 431 nm. SEM showed the presence of several silver particles at the nanoscale, which indicates the success of the AgNPs biosynthesis. Furthermore, X-ray diffraction showed that the AgNPs are crystalline and face-centered cubic (FCC) in nature, while FT-IR spectral analysis identified the number of functional biological groups that serve as capping or stabilizing agents in the stabilization of nanoparticles. The presence of the silver element in the produced AgNPs was further confirmed by EDX. The green-produced AgNPs exhibit effective antibacterial activity against urinary tract infection-causing isolates of bacteria. The concentration of 8 mM showed the highest rate of inhibition zone against Escherichia coli, Staphylococcus spp., Pseudomonas aeruginosa and Klebsiella pneumoniae with inhibition zone value of 19 mm, 17.4 mm, 12.6 mm and 10.7 mm respectively. These results imply that isolates of E. coli are the main target of AgNPs' inhibitory action. Furthermore, at 75 µg/mL, AgNPs show efficient antioxidant activity (IC50), which is greater than that of the common antioxidant Trolox, which reduces the ABTS radical at 25 µg/mL.