Green synthesis of cerium oxide nanoparticles using Tribulus terrestris: characterization and evaluation of antioxidant, anti-inflammatory and antibacterial efficacy against wound isolates

Abstract Multi-drug resistance (MDR) infections are a significant global challenge, necessitating innovative and eco-friendly approaches for developing effective antimicrobial agents. This study focuses on the synthesis, characterization, and evaluation of cerium oxide nanoparticles (CeO 2 NPs) for their antioxidant, anti-inflammatory, and antibacterial properties. The CeO 2 NPs were synthesized using a Tribulus terrestris aqueous extract through an environmentally friendly process. Characterization techniques included UV–visible spectroscopy, Fourier Transform Infrared Spectroscopy (FT-IR), x-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive x-ray (EDX) analysis. The UV–vis spectroscopy shows the presence of peak at 320 nm which confirms the formation of CeO 2 NPs. The FT-IR analysis of the CeO 2 NPs revealed several distinct functional groups, with peak values at 3287, 2920, 2340, 1640, 1538, 1066, 714, and 574 cm −1 . These peaks correspond to specific functional groups, including C-H stretching in alkynes and alkanes, C=C=O, C=C, alkanes, C-O-C, C-Cl, and C-Br, indicating the presence of diverse chemical bonds within the CeO 2 NPs. XRD revealed that the nanoparticles were highly crystalline with a face-centered cubic structure, and SEM images showed irregularly shaped, agglomerated particles ranging from 100–150 nm. In terms of biological activity, the synthesized CeO 2 NPs demonstrated significant antioxidant and anti-inflammatory properties. The nanoparticles exhibited 82.54% antioxidant activity at 100 μg ml −1 , closely matching the 83.1% activity of ascorbic acid. Additionally, the CeO 2 NPs showed 65.2% anti-inflammatory activity at the same concentration, compared to 70.1% for a standard drug. Antibacterial testing revealed that the CeO 2 NPs were particularly effective against multi-drug resistant strains, including Pseudomonas aeruginosa , Enterococcus faecalis , and MRSA, with moderate activity against Klebsiella pneumoniae . These findings suggest that CeO 2 NPs synthesized via T. terrestris have strong potential as antimicrobial agents in addressing MDR infections.