Antibacterial Activity of CuO Nanoparticles Synthesized by Justicia adhatoda Leaf Extract

Aims: To determine the antibacterial activity of CuO nanoparticles (CuO NPs) synthesized by Justicia adhatoda leaf extract.

Study Design: Synthesis, characterization and antibacterial activity determination of CuO NPs.

Place and Duration of Study: PG and Research Department of Chemistry, V.O.Chidambaram College, Tuticorin, Tamilnadu, India, between April 2019 and April 2020.

Methodology: CuO NPs were synthesised using Justicia adhatoda leaf extract. UV-Visible spectroscopy was used to characterize CuO NPs. The role of biomolecules in plant extract in the formation of the CuO NPs was identified using Fourier transform infrared spectroscopy. The particle size and lattice properties of CuO NPs were determined using XRD. The surface morphology of CuO NPs was studied using SEM. The presence of Cu and O in CuO NPs was confirmed using EDAX analysis. Bacterial antimicrobial activity was investigated.

Results: An absorbance band at 285 nm in the UV–visible spectrum clearly revealed the formation of CuO NPs. In the FTIR, CuO NPs had a distinct absorption peak at 608 cm-1, confirming metal–oxygen stretching in Cu-O nanostructures. The presence of crystalline CuO NPs was confirmed by XRD patterns, and they were found to be spherical in shape with a size range of 23.21–37.57 nm, as evidenced by FESEM. The biosynthesized CuO NPs exhibited a strong antibacterial activity against Staphylococcus epidermidis and Bacillus cereus bacteria.

Conclusion: Justicia adhatoda leaf extract mediated CuO NPs have shown significant antibacterial activity and they are considered potent antibacterial agents.