In this study, silver nanoparticles (AgNPs) were synthesized using a biological method with orange (Citrus sinensis) peel essential oil (CsEO) as a reducing and stabilizing agent. UV-Vis spectroscopy results showed a characteristic absorption peak around 400-405 nm, reflecting the successful formation of AgNPs. Fourier-transform infrared spectroscopy indicated the presence of functional groups such as -OH, C=O, C-H, and C-O, confirming the role of phytochemical compounds in CsEO in reducing and stabilizing the nanoparticles. Dynamic light scattering (DLS) results indicated an average particle size of approximately 74.1 nm, with a distribution range of 270 to 280 nm, consistent with stable nanoscale properties observed in previous studies. Scanning electron microscopy (SEM) images revealed that the particles were spherical in shape, uniformly distributed, and displayed less agglomeration. AgNPs-CsEO exhibited significant antibacterial activity against both Gram-negative and Gram-positive bacteria, especially against Salmonella enteritidis (19.13 mm), Escherichia coli (16.47 mm), Staphylococcus aureus (9.75 mm), and Bacillus cereus (16.80 mm). 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays were used to measure antioxidant activity; the IC50 values were 56.72±3.72 μg/mL and 98.63±6.84 μg/mL, respectively. These results indicate the potential application of AgNPs-CsEO in the fields of food, pharmaceuticals, and biomedical materials.
Phuong et al. (Wed,) studied this question.