Phytomediated synthesis of copper oxide nanoparticles from floating fern Salvinia cucullata Roxb. and their antibacterial, antioxidant, and anticancer potential

The plant-based green synthesis method is creating more interest in safety, low-cost, biocompatibility, and eco-friendly approaches to producing nanoparticles biologically than chemical and physical methods of synthesis. The copper oxide nanoparticles (CuONPs) attract researchers due to the wide range of industrial, pharmacological, and biomedical applications that depend on the size, charge, and shape of the nanoparticles. This research work aimed to synthesize CuO nanoparticles using aqueous extract of Salvinia cucullata, characterization, and assessment of in vitro antibacterial, antioxidant, and anticancer activity. The characterization of CuONPs was performed by different techniques which include UV spectroscopy, FTIR, XRD, TEM, SEM, EDXS, and Zeta size and potential analysis. UV spectroscopy confirms the synthesis of CuONPs with an absorbance peak of 266 nm. The monoclinic crystalline nature of CuONPs was revealed by XRD analysis, and this pattern exhibited similar diffraction peaks with no significant shift in peak position. The functional groups of phytocomponents present in the aqueous extract of S. cucullata which act as reducing and stabilizing agents responsible for CuONPs synthesis were analyzed by the FTIR technique. The spherical shape of the synthesized CuONPs was ascertained by SEM and TEM image techniques, and the selected area for electron diffraction shows the crystal orientation of the CuONPs. EDXS shows that only copper and oxygen were present and the synthesized CuONPs are in pure form. The average size and charge of the synthesized CuONPs were analyzed by PSA as 67.5 nm and − 2.2 mV. The antibacterial potential of synthesized CuONPs was tested against both gram- positive and gram-negative bacterial strains. Among all eight strains, the maximum and minimum zone of inhibition was observed against Enterococcus spp. and Aeromonas hydrophila (maximum inhibition against gram-positive strains than gram-negative strains). The antioxidant and anticancer activity of CuONPs were tested against DPPH and MCF-7 breast cancer cell line and are observed with increased activity in a dose-depending manner with the IC50 value of 81.21 μg/ml and 68.16 μg/ml concentration. The green synthesized CuONPs were characterized and exhibited antibacterial, antioxidant, and anticancer activity. Thus, CuONPs can be utilized for broad-spectrum biomedical applications.