Green Synthesis of Chromium Oxide Nanoparticles Using Arachis hypogaea Leaf Extract with Antibacterial and Anti-enzymatic Activity against Phytopathogenic Bacteria

Green synthesis of metal oxide nanoparticles offers an eco-friendly route for developing functional antimicrobial materials. In this study, chromium (III) oxide (Cr₂O₃) nanoparticles were synthesized using Arachis hypogaea leaf extract as a reducing and stabilizing agent and evaluated for antibacterial and anti-virulence activity against Erwinia carotovora and Pseudomonas fluorescens. The nanoparticles were tested at final concentrations of 15, 25, and 35 µg/mL. Results showed concentration-dependent antibacterial activity, with inhibition zones reaching 46.0 ± 1.2 mm for Erwinia carotovora and 39.0 ± 1.0 mm for Pseudomonas fluorescens at 35 µg/mL. In addition, Cr₂O₃ nanoparticles significantly reduced the activity of key extracellular virulence enzymes, including cellulase and pectinase. These findings demonstrate that green-synthesized Cr₂O₃ nanoparticles exhibit dual antibacterial and anti-virulence properties, supporting their potential application as environmentally friendly antimicrobial materials.