Biosynthesis of a biovaccination based on copper nanocomposites and study of their effectiveness to protect against bacterial infections

Abstract

This work investigates the biosynthesis of a biovaccination based on copper nanocomposites (CuNPs) using Salmonella enterica and Escherichia coli bacteria and the study of their effectiveness to protect against bacterial infections. Furthermore, UV-Vis and FT-IR spectroscopy, scanning electron microscopes (SEM) and EDX technique were used to verify the biosynthesis of copper nanoperticles. In-vitro antioxidant and anti-inflammatory activities of copper nanocomposites were evaluated by standard techniques. In in-vivo study, twenty male albino Wistar rats were randomly diveded to five groups (four rats in each): (1) healthy rats (control), (2) rats infected with S. enterica, (3) rats infected with E. coli, (4) rats vaccinated with SE-CuNPs and subsequently exposed to S. enterica, and (5) rats vaccinated with EC-CuNPs and subsequently exposed to with E. coli. The biovaccination was done by intraperitoneal injection at a dose of 7 mg/kg. After a two-week period, all groups, except the control, were exposed to a bacterial dose. Some hematological, biochemical, enzymatic parameters, and oxidative stress markers were evaluated, along with conducting microscopic examinations of spleen tissue. Results of in-vitro study revealed that EC-CuNPs and SE-CuNPs exhibited oval shapes with sizes ranging from 73 to 183 nm and from 135 to 202 nm, respectively. EC￾CuONPs showed high antioxidant activity (IC50= 61.86 μg/ml), while SC-CuNPs exhibited enhanced anti-hemolysis activity (IC50= 40.1 μg/ml). The biological findings indicate significant alterations induced by bacterial infection, including physiological changes and disturbances in biochemical parameters and antioxidant defense systems in various organs. Rats vaccinated with SE-CuNPs and EC￾CuNPs showed significant improvements in biological parameters and histological analyses, suggesting the efficacy of vaccination in mitigating bacterial infection damage. These findings suggest that both biovaccins SE-CuNPs and EC-CuNPs are effective in providing protection against bacterial infection with minimal side effe