Green nanoparticles synthesized from damask rose petals: Evaluation of their antioxidant, antimicrobial, anti-diabetic, anti-Alzheimer, and photocatalytic properties

Green synthesis, an approach that has gained widespread recognition in recent years due to environmental and health concerns, was employed to synthesize green zinc oxide nanoparticles (G-ZnO NPs) using a hydro-alcoholic extract derived from dried damask rose petals. The synthesized nanoparticles were confirmed using an X-ray diffractometer, UV-visible, and Fourier transform infrared spectrometry. A morphological examination with a field emission scanning electron microscope revealed that the G-ZnO NPs had a diameter ranging from 44.66 to 83.74 nm and a purity of 93.2 %. Furthermore, the antioxidant, photocatalytic, antimicrobial, and anti-diabetic properties of G-ZnO NPs were investigated and compared with two commercial ZnO NPs of different sizes (C-ZnO NPs1 (10-30 nm) and C-ZnO NPs2 (50-60 nm)). The G-ZnO NPs demonstrated the highest antioxidant activity (46.49 %). In terms of photocatalytic activity against methylene blue, G-ZnO NPs exhibited a higher degradation rate (61 %) than C-ZnO NPs1 and C-ZnO NPs2 (53.65 and 25.63 %). The ability of nanoparticles to inhibit the growth of two bacteria <i>Escherichia coli</i> and <i>Staphylococcus aureus</i> showed that G-ZnO NPs displayed the highest inhibition rate against bacterial growth for both strains. Finally, the inhibitory effect of ZnO NPs on α-glucosidase and acetylcholinesterase enzymes was examined, revealing significant inhibition. G-ZnO NPs (600 μg/ml) exhibited stronger inhibitory effects compared to C-ZnO NPs1 and C-ZnO NPs2 for both enzymes.