Investigation of the Antioxidant, Antibacterial, and Food Safety Potential of Silver and Copper Nanoparticles Green Synthesized Using Pointed Cherry Laurel (Prunus laurocerasus L.) Extract

Abstract This study reports the green synthesis of silver (PFAgNPs) and copper (PFCuNPs) nanoparticles using an aqueous extract of pointed cherry laurel (Prunus laurocerasus L.) fruit (PF-E) and explores their applicability in food safety. The NPs were characterized via UV–Vis spectroscopy, FT-IR, XRD, SEM, EDX, and TEM confirming their successful formation and morphology. Total phenolic content (TPC), flavonoid content (TFC), and antioxidant capacity (TAC) were measured for both PF-E and the synthesized NPs. While PFCuNPs exhibited higher TPC, PFAgNPs showed superior TFC and TAC. Notably, antioxidant assays (DPPH, ABTS, FRAP) indicated stronger radical scavenging activity for PFCuNPs. Antibacterial tests against Escherichia coli , Enterococcus faecalis , Staphylococcus aureus , and Pseudomonas aeruginosa revealed broad-spectrum activity of PFAgNPs, with the highest inhibition against E. coli (19.4 ± 0.3 mm), whereas PFCuNPs showed dose-dependent efficacy, strongest against E. faecalis (9.6 ± 0.2 mm). LC–MS/MS analysis of the PF-E extract revealed quinic acid (63.42 mg/g), chlorogenic acid (2.38 mg/g), protocatechuic acid (0.07 mg/g), protocatechuic aldehyde (0.04 mg/g), hesperidin (0.03 mg/g), and naringenin (0.02 mg/g) as major components. The adsorption efficiencies of the synthesized PFAgNPs and PFCuNPs were evaluated against the toxic food contaminants patulin and HMF using both standard aqueous solutions and real food systems (apple juice). In standard aqueous solutions, PFAgNPs achieved removal efficiencies of 70.96% for patulin and 52.22% for HMF, while PFCuNPs showed 61.08% and 36.38%, respectively, at 5 g/L after 240 min. In real food systems, the adsorption efficiencies decreased, with PFAgNPs and PFCuNPs removing 34.24% and 32.90% of patulin, and 39.09% and 31.87% of HMF, respectively. The adsorption kinetics of HMF and patulin onto PFCuNP and PFAgNP were found to conform to both the pseudo-first-order and pseudo-second-order kinetic models for aqueous solutions as well as real samples. These findings confirm that the biosynthesized NPs offer dual functionality as antibacterial agents and toxin adsorbents, presenting a green, sustainable approach to food safety enhancement.