Biosynthesis, Characterization, Antibacterial and Anti-Biofilm Activity of CuO Nanoparticles using Ephedra major Plant Extract against Pseudomonas aeruginosa.

Abstract

Introduction: Nanoparticles are nanometer-sized particles that have unique properties and are used in various fields such as medicine, environment, and technology. The Ephedra major plant, with its medicinal properties, is a rich source for extracting molecules that can be used as agents for the biosynthesis of nanoparticles and improve their properties. The aim of the current study was the biosynthesis of copper oxide nanoparticles (CuONPs) using Ephedra major extracts, as well as the evaluation of their antibacterial and anti-biofilm activity against Pseudomonas aeruginosa.

Materials and methods: The synthesis of CuO nanoparticles was performed using the aqueous extract of the leaves of Ephedra major plant .The synthesized nanoparticles were evaluated by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The well diffusion method investigated the antimicrobial activity of CuO-NPs synthesized against Pseudomonas aeruginosa. Then, the MIC and MBC of the synthesized nanoparticles were determined in 96-well microplates with different concentrations of CuO-NPs, aqueous extract, and chloramphenicol. The inhibition of Pseudomonas aeruginosa biofilm was investigated by staining with 1% crystal violet.

Results: The results of the UV-Vis analysis showed that the absorption at the wavelength of 385 nm was the highest, which confirmed the formation of CuO-NPs. SEM and EDX results indicated that the nanoparticles formed in a spherical shape with an average size of 30 to 80 nm. Also, EDX analysis showed the presence of copper, carbon, and oxygen elements in nanoparticles. The CuO-PNs at the concentration of 2000 μg/ml exhibited a significant inhibitory effect against P. aeruginosa. Also, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of nanoparticles were 312 μg/ml. In addition, the results showed that CuO-NPs have an effect in inhibiting biofilm formation.The inhibitory effect against biofilm was greater with increasing concentration.

Conclusion: The results of this study prove that CuO-NPs synthesized from the aqueous extract of Ephedra major plant can be used as an effective option in treating infections caused by P. aeruginosa.