In-vitro bactericidal and anti-oxidant efficacy of biosynthesized CuO/Cu2O-NiO nanocomposites against the pathogenic bacteria and DPPH free radical

Abstract The biosynthesis of CuO/Cu 2 O-NiO nanocomposites with ratios of 90:10, 80:20, and 70:30 was conducted using Ipomoea carnea leaf extract. This study investigates, for the first time, the antioxidant and antibacterial activities of these nanocomposites against 1,1-diphenyl-2-picryl hydroxyl, Bacillus subtilis , Escherichia coli , and Staphylococcus aureus pathogens. The antibacterial effect of 90:10 nanocomposites (NCs A1) was found to be enhanced compared to 80:20 (NCs B1) and 70:30 (NCs C1) due to particle aggregation, significant reactive oxygen species production, uniform quantum size, and ideal crystalline size. However, 70:30 nanocomposites (NCs C1) exhibited high radical scavenging activity (96.40%), surpassing ascorbic acid (98.63%). The current study revealed that  Ipomoea carnea  plant extract-based 90:10, 80:20, and 70:30 CuO/Cu 2 O-NiO NCs work as a new substitute for the currently utilized antibacterial agents, which are answerable for the multi-drug resistance in common bacteria for living beings and also used for biological importance as antibacterial agents in food packaging industries.