Biosynthesis and Evaluation of the Qualitative Characteristics of Bacillus subtilis Silver Nanoparticles as Biopesticides

Silver nanoparticles (AgNPs) were biosynthesized using Bacillus subtilis bacteria and characterized. First, the reaction color change from light to dark indicated the production of AgNPs. After that, the AgNPs were characterized by conducting a series of tests. UV/Vis spectrometer examination showed the highest value of the ultraviolet spectrum at 401 nm. The Fourier-transform infrared spectroscopy spectrometry examination showed primary and secondary amides from the solution, as evidenced by the presence of amino acid residues and proteins that strongly bind metals. When measuring X-ray diffraction of the resulting AgNPs, the crystal structure was cubic, and the crystal planes formed were (111), (200), (220), and (311), which correspond to the diffraction angles (38.117, 44.270, 64.425, and 77.424?). Scanning electron microscopy showed homogeneous spherical shapes of AgNPs ranging from 15.05 to 20.61 nm..