Antibacterial and Antibiofilm Activity of Eucalyptus camaldulensis Derived Fe3O4 Nano-particles against Foodborne Pathogens

Foodborne pathogens are zoonotic and multidrug resistant, which are not only affecting economy but also accountable for public health burdens. The present study was aimed to evaluate the efficacy of medicinal plant i.e., Eucalyptus camaldulensis extract mediated Fe3O4 and ZnO nanoparticles against the 27 foodborne pathogenic strains, isolated from milk, meat, dry fruits and vegetable samples collected from Multan, Pakistan. In phytochemical screening, the plant extract was found to contain numerous bioactive compounds including flavonoids, phenolic compounds, tannins, quinones, and anthocyanins. Fe3O4 NPs synthesized from Eucalyptus camaldulensis displayed the highest antibacterial activity with zones of inhibition of 12-13mm against pathogens. Fe3O4 NPs were found to have highest anti-inflammatory potential with recorded percentage of 67% at 40 μg/ml. Fe3O4 NPs also demonstrated the highest antibiofilm activity after 120 hours of incubation. For DDPH antioxidant assay, the highest antioxidant activity was displayed by Fe3O4 NPs and their absorbance recorded was 1.43. Therefore, Eucalyptus camaldulensis mediated Fe3O4 NPs proved as an effective and eco-friendly approach to combat multidrug resistance in bacterial infections throughcharacteristic antibacterial, antibiofilm and antioxidant properties.