Green Biosynthesis of Bimetallic Copper Oxide-Selenium Nanoparticles Using Leaf Extract of Lagenaria Siceraria: Antibacterial, Anti-Virulence Activities Against Multidrug-Resistant Pseudomonas Aeruginosa

INTRODUCTION: Clinical isolates of Pseudomonas aeruginosa (P. aeruginosa) are among the most recovered bacteria with phenotypic antimicrobial resistance. Bimetallic nanoparticles (BNPs) have received much attention for antimicrobial activity in the last decade. This research aimed to biosynthesize bimetallic copper oxide-selenium nanoparticles (CuO-Se BNPs) and to assess its bioactivity on various P. aeruginosa clinical isolates.

METHODOLOGY: Based on the possible synergistic effects, CuO-Se BNPs were selected and biosynthesized using leaf extract of Lagenaria siceraria (L. siceraria) for the first time. The obtained BNPs were characterized using UV-vis spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and transmission and scanning electron microscopes. The capability of Cu-Se BNPs to cease the growth of P. aeruginosa isolates and to reduce their virulence characters was evaluated. Also, different cell lines were used to assess its cytotoxicity and anticancer activity.

RESULTS: The elemental composition of CuO and Se was revealed by the UV, XRD, and EDX data, indicating the synthesis of CuO-Se core shell BNPs with a size of 50 nm. In well diffusion assay, CuO-Se BNPs P. aeruginosa growth with 10-21 mm inhibition zone diameter and 38-95% inhibition. Also, the minimum inhibitory concentration and minimum bactericidal concentration were in a relatively wide range of 7.8-250 μg/mL and 31.2-500 μg/mL, respectively, with tolerance level range of 2-16. Additionally, CuO-Se BNPs shown anti-pyocyanin activity of 4.35-63.21% inhibition while the anti-proteolytic activity was in a range of 4.96-12.59% and anti-pyoverdine effect was in a range of 0.24-83.41%. The IC50 against Wi-38 normal cells was 267.2 µg/mL while the IC50 were 31.1 and 83.4 µg/mL against MCF-7 and Hep-G2, respectively, indicating promising anticancer activity.

CONCLUSION: This research demonstrates the promising antibacterial, anti-virulence, and antitumor properties with safe low concentrations of CuO-Se NPs, synthesized via an eco-friendly green synthesis method without the use of toxic chemicals, offering a sustainable and cost-effective alternative.