Antibacterial and antifungal activities of Platycladus orientalis leaf extract-mediated Fe₂O₃ and Ce-doped Fe₂O₃ nanoparticles

Green synthesis of nanomaterials harnesses naturally occurring materials, including plant extracts, to offer environmentally friendly alternatives to conventional biomedicine, agriculture, and other field applications. This study explores the green route to Fe₂O₃ and cerium-doped Fe₂O₃ (Ce-doped Fe₂O₃) nanoparticles synthesized for the first time using the leaf extract of Platycladus orientalis. The synthesized nanoparticles were characterized for their structural, morphological, chemical, and optical properties. The hematite phase of Fe₂O₃ nanoparticles with spherical morphology was obtained. The introduction of Ce as a dopant into Fe₂O₃ increased the lattice strain of Ce-doped Fe₂O₃ nanoparticles (0.51%) compared to pristine Fe₂O₃ (0.46%) even though the size of both nanomaterials was similar. Compared to pristine Fe₂O₃ nanoparticles, Ce-doped Fe₂O₃ nanoparticles also demonstrated enhanced antimicrobial and antifungal activities against Escherichia coli, Enterococcus faecalis, Listeria monocytogenes, Penicillium chrysogenum, Aspergillus niger, and Mucor mucedo. The green-synthesized Ce-doped Fe₂O₃ nanoparticles possess potential for application in biomedical and environmental fields based on their relevance to human health and food safety, diversity in microbial characteristics, and potential for resistance to conventional treatments.