Green Synthesis of Iron Nanoparticles Using Punica granatum Extract and Evaluation of Their Biological Potential

Abstract

This study investigates the phytochemical composition and biological activities of Punica granatum peel extract and green-synthesized iron nanoparticles (FeNPs) were explored. The FeNPs were synthesized using an aqueous extract of P. granatum peel, with methanol and deionized water as solvents. Phytochemical analysis revealed the presence of phenols, tannins, alkaloids, flavonoids, and steroids. The FeNPs were characterized by UV-Vis spectroscopy, which showed a distinct absorption peak at 366 nm, indicating the presence of Fe-NPs. Fourier-transform infrared (FT-IR) spectroscopy revealed bands corresponding to phenolic and methyl C-H groups, confirming the role of the extract in reducing FeCl₃ to Fe-NPs. Energy dispersive X-ray (EDX) analysis identified iron, carbon, and oxygen, suggesting the formation of iron oxide (Fe₂O₃) nanoparticles. X-ray diffraction (XRD) patterns displayed sharp peaks, confirming the crystalline nature of the Fe-NPs, with additional peaks indicating the presence of carbon. Scanning electron microscopy (SEM) images revealed uniformly distributed, nearly spherical nanoparticles ranging from 19.8 nm to 48 nm in size.

Biological activity tests showed that the peel extract exhibited significant antibacterial effects, inhibiting Staphylococcus aureus (61.53%), Pseudomonas aeruginosa (51.58%), Klebsiella pneumoniae (57.54%), Bacillus pumilus (48%), Salmonella Typhi (33.33%), and Escherichia coli (30.43%). The FeNPs demonstrated enhanced antibacterial activity, with inhibition rates of 73.07%, 66.66%, 76.19%, 56%, 40.74%, and 34.78%. Additionally, both the FeNPs and methanolic extract showed notable insecticidal activity against Tribolium castaneum (60%), Carpophilus analis (70%), and Rhizopertha dominica (50%). Phytotoxic effects were observed at higher concentrations, highlighting their potential for antibacterial, insecticidal, and phytotoxic applications.