Antimicrobial and Catalytic Activities of Green Synthesized Silver Nanoparticles Using Bay Laurel (Laurus nobilis) Leaves Extract

In this study, bay laurel extract (BLE) used as a reducing and capping agent for the synthesis of silver nanoparticles (AgNPs). The green-prepared AgNPs investigated using UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), Scanning Electron Microscopy with Energy Dispersive X-ray (SEM-EDX) and Transmission electron microscopy (TEM). Formation of AgNPs monitored at ambient temperature by a change in color from the starting solution to dark brown. Green synthesis AgNps were investigated for antimicrobial activity. The microorganisms employed were E. coli, K. pneumoniae, B. cereus, S. aureus, C. lbicans and Aspergillus. The susceptibility of microorganisms against the six AgNPs solutions was determined using the disk diffusion method. The catalytic activity of the prepared AgNPs (sample, d) for basic brown 1 dye was investigated. The results showed the characteristic surface plasmon resonance peak of the AgNPs appeared at approximately 415 - 440 nm. XRD revealed peaks at 38.2, 44.16, 64.24 and 77.22 Ɵ, and the intensity of these peaks enhanced when using microwave curing compared to ambient temperature. SEM and TEM results showed that the silver nano particles have a spherical shape and the particle size for samples is less than 34 nm. FTIR spectroscopy measurements showed the binding of organic compounds on the surface of the silver nanoparticles. Highest antibacterial activity was enhanced with increasing of AgNPs dose and with increasing of extract ration against most of microorganisms except. Removal of basic brown 1 dye by the prepared AgNPs indicated complete dye removal after 8 h.