Antibacterial and antifungal activity of green synthesized silver nanoparticles using aqueous extracts of Silybum marianum L. and Portulaca oleracea L.

The use of plant extracts to produce metal particles at the nanoscale has attracted intensive research interest due to their cost-effectiveness and eco-friendliness. This study aimed to investigate the synthesis of silver nanoparticles (AgNPs( using aqueous extracts of Silybum marianum L. and Portulaca oleracea L. and to assess their effectiveness as antibacterial and antifungal agents using the agar-well diffusion method. The production of AgNPs was confirmed through spectrophotometry, and their size and shape were measured using Transmission Electron Microscopy (TEM). The role of organic compounds in nanoparticle synthesis was also explored through Fourier Transform Infrared Spectroscopy (FTIR). The FTIR analysis identified the functional groups of organic compounds in S. marianum and P. oleracea extracts that were responsible for reducing Ag ions and capping the resulting AgNPs. The nanoparticles demonstrated potent antimicrobial properties against Escherichia coli, Staphylococcus aureus, Fusarium graminearum, and Alternaria alternata. It was concluded that, in addition to their unique medicinal properties, S. marianum and P. oleracea can be utilized in the production of AgNP for medical and pharmaceutical purposes against Gram-positive and Gram-negative bacteria, as well as fungal infections. In summary, the seed extracts of S. marianum and P. oleracea, which are among the available plant sources, can be used for the highly stable production of AgNPs as a reducing and capping agent.