Investigating the antimicrobial & antioxidant potential of copper oxide nanoparticles derived from Azolla pinnata

In this study, we fabricate Copper Oxide Nanoparticles (CuO NPs) through a green synthesis method using plant extracts. We assessed their antimicrobial and antioxidant activities. For the antimicrobial tests, we used the zone of inhibition method against common dental pathogens, Staphylococcus aureus and Escherichia coli , comparing the results to standard tetracycline. CuO NPs showed strong antibacterial activity, with the largest inhibition zone against S. aureus at concentrations of 50 mg/L and 70 mg/L. The antibacterial action comes from the electrostatic interaction between the positively charged Cu ions and the negatively charged bacterial cell membranes, which disrupt and kills the cells. We evaluated the antioxidant activity using the DPPH radical scavenging assay. This showed that the scavenging efficiency increased with concentration. The highest scavenging activity of 72% was noted at 90 mg/mL, with an IC₅₀ value of 36.19 mg/mL, indicating moderate antioxidant potential. Functional groups like hydroxyl, carbonyl, and ether formed during the green synthesis likely enhance the bioactivity observed. The dual functionality of CuO NPs suggests they could be useful in biomedical applications, including antimicrobial treatment and antioxidant formulations.