Fabrication of chitosan/CuO/grape seed extract biocomposite exhibiting synergistic antioxidant and antibacterial activity

The overuse of antibiotics has resulted in antibiotic-resistant microorganisms, a worldwide health concern. This resistance interferes with treatment methods and requires new approaches. Antibacterial and antioxidant nanocomposites represent promising fields of research. These nanocomposites may enhance traditional antibiotics by mitigating cellular oxidative stress and combating pathogens. The unique characteristics of nanomaterials will be utilized to provide efficient treatments for resistant bacterial strains. The current study's goal was to investigate the antibacterial and antioxidant qualities of chitosan (CS)/copper oxide nanoparticles (CuONPs) mediated by grape seed extract (GSE). Consequently, the biosynthesized materials were characterized by using several techniques involving transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), elemental analysis (EDX), and Fourier transform infrared spectrum (FTIR). The prepared CS/CuO/GSE nanocomposite revealed significant scavenging efficacy (74.2 ± 3.43 % at a 100 μg/mL) concentration for a DPPH radical (2,2-diphenyl-1-picrylhydrazyl), comparable with that of ascorbic acid (87.43 ± 0.89 %), regarded as a standard employing the agar well diffusion technique. The antibacterial efficacy of CS/GSE/CuO was examined, and minimal inhibitory concentrations were determined. In antibacterial assays, CS/CuO/GSE demonstrated the inhibition zone in Escherichia coli. at 9 mm and Streptococcus mutans at 14 mm at 100 µg/ml, respectively. Also, the MIC of the CS/CuO/GSE against Streptococcus mutans and Escherichia coli was determined to be 312μg/ml and 5 mg/ml, respectively. As demonstrated by experiments, the (CS/CuO/GSE) composite shows remarkable biological efficacy, particularly in antioxidant and antibacterial activity.