Biofabrication of Silver Nanoparticles Using Pergularia tomentosa Extract and Evaluation of Their Antibacterial, Antioxidant, and Cytotoxic Properties

The biosynthesis of silver nanoparticles using plant extracts is a promising field of research because of the useful biomedical applications of metal nanoparticles. In this study, the antibacterial and antioxidant properties of silver nanoparticles biosynthesized with the aqueous leaf extract of <i>Pergularia tomentosa</i> were defined using a simple, eco-friendly, consistent, and cost-effective method. The leaf extract of <i>Pergularia tomentosa</i> (PT) served as a capping and reducing agent to biosynthesize silver nanoparticles. The effects of several parameters, such as the concentration of AgNO₃, ratio of AgNO₃ to extract, pH, and incubation time, were examined to optimize the synthesis process. In total, 5 mM of AgNO₃, a 1:0.06 ratio of AgNO₃ to <i>Pergularia tomentosa</i> extract, pH 9.0, and reaction mixture incubation for 24 h were found to be the ideal parameters for biosynthesizing silver nanoparticles (AgNPs). UV-visible spectroscopy, X-ray diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), and scanning electron microscopy were used to characterize the biosynthesized <i>Pergularia tomentosa</i> silver nanoparticles (PT-AgNPs). Gram-positive bacteria (<i>Staphylococcus aureus</i> and <i>Bacillus cereus</i>) and Gram-negative bacteria (<i>Salmonella enteritides</i> and <i>Escherichia coli</i>) were used to test the PT-AgNPs' antibacterial activity. The presence of different functional groups was determined using FTIR. The AgNPs were hexagon shaped. The nanoparticles were more toxic against <i>S. enteritides</i> than both <i>B. cereus</i> and <i>E. coli</i>. In antioxidant analyses, the AgNPs were found to be as strong at free radical scavenging as gallic acid (standard), with IC₅₀ values of 0.69 and 22.30 μg/mL for DPPH and ABTS radicals, respectively. Interestingly, the PT-AgNPs displayed increased anti-inflammatory activity compared with the <i>P. tomentosa</i> leaf extract (79% vs. 59% at 500 µg/mL). The PT-AgNPs did not display any cytotoxicity against the MCF-7 cell line at the MIC. In conclusion, silver nanoparticles fortified with <i>Pergularia tomentosa</i> extract exhibited potential as effective antibacterial, anti-inflammatory, and antioxidant agents, suggesting their viability as alternatives to commercially available products.