Green synthesis of silver nanoparticles using Catalpa bignonioides fruit

For the first time, the aqueous extract of Catalpa bignonioides fruit was used as a reducing agent in the synthesis of silver nanoparticles with antibacterial and antioxidant properties by the green method. Physicochemical, antioxidant, and antibacterial properties of silver nanoparticles were investigated. The synthesized silver nanoparticles were characterized by UV–visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscope, and dynamic light scattering methods. The synthesis of silver nanoparticles was confirmed by red-brown color formation for visual observation. The surface plasmon resonance peak was observed at about 419 nm. The physicochemical test result shows that the average particle size of silver nanoparticles was between 22 and 31 nm. According to the antibacterial test results, silver nanoparticles exhibited good antibacterial properties by inhibiting the growth of gram-positive Staphylococcus aureus and gram-negative bacteria Escherichia coli. The 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity of the synthesized silver nanoparticles was investigated, and they exhibited antioxidant activity. Antibacterial and antioxidant silver nanoparticles have the potential to be used in textiles, cosmetics, food packaging, and biomedical applications.