One-step phytosynthesis of Co3O4 nanoparticles and study of their catalytic, antioxidant, antibiofilm and antibacterial activities

Co 3 O 4 nanoparticles (NPs) were synthesized using Citrus lemon leaf extract, a novel green method. The synthesized NPs were extensively characterized using FTIR, UV-VIS, XRD, and SEM techniques, confirming their synthesis and properties. These NPs demonstrated promising catalytic efficiency (% degradation = 75.16 %), antioxidant potential (IC50 = 0.7 mg/ml), anti-biofilm activity (IC50 = 0.096 ± 0.005 mg/ml for E. coli , 0.08 ± 0.007 mg/ml for S. aureus ) and antibacterial effects (ZOI = 28 mm for E. coli , 23 mm for S. aureus ). This green synthesis method offers scalability and cost-effectiveness as compared to the energy-intensive and wasteful traditional methods. Our study exemplifies a commitment to advancing scientific progress through sustainable practices, contributing to global sustainable development goals. • Co 3 O 4 nanoparticles synthesized using citrus lemon leaf extract • NPs demonstrating 69 % degradation/removal of methyl orange • Antioxidant potential (IC50 = 0.7 mg/mL) of cobalt oxide NPs was promising • Anti-biofilm activity was also demonstrated (IC50 = 0.096 ± 0.005 mg/ml for E. coli , 0.08 ± 0.007 mg/ml for S. aureus ) • Antibacterial effects also successful (ZOI = 28 mm for E. coli , 23 mm for S. aureus )