Novel Eco-Friendly Synthesis of CoO NPs: Evaluation of Their Diode Laser-Enhanced Inhibitory Activity Through Combined In Silico and In Vitro Approaches.

In our study, for the first time worldwide, to the best of our knowledge, cobalt oxide nanoparticles (CoO NPs) were synthesized using naringin (Nar) extracted from citrus peels. The properties of the prepared Nar-CoO NPs were studied using field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), ultraviolet-visible (UV-Vis), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. All the test results demonstrated the efficiency and success of the nanofabrication process. The solution was then exposed to three types of diode lasers: red (650 nm), green (532 nm), and blue (405 nm). The purpose of this study was to investigate the effect of the diode laser on the inhibitory activity of Nar-CoO NPs against common bacterial species causing urinary tract infections (UTIs), namely Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The inhibitory effect was greater against E. coli than against S. aureus. The molecular docking of naringin with a set of important proteins in the studied bacteria was also investigated. For E. coli, the proteins 1BTL, 9N6C, 6GTS, and 5FCD were targeted, yielding binding affinities of -7.6 to -10.2 kcal/mol. For S. aureus, the proteins 1BQB, 3RTL, 4M00, and 7PCH were targeted, yielding binding affinities ranging from -7.5 to -9.1 kcal/mol. We concluded that the synthesis process was efficient and that the ligand played a crucial role in inhibiting the functions of many proteins essential for virulence, pathogenicity, and antibiotic resistance, as demonstrated by its high inhibitory activity.