Bacterial-mediated synthesis and characterization of copper oxide nanoparticles with antibacterial, antioxidant, and anticancer potentials

Abstract

The application of novel bacterial strains for effective biosynthesis of nanoparticles minimizes negative environmental impact and eliminates challenges of available approaches. In the present study, cell-free extract of Stenotrophomonas sp. BS95. was used for synthesis of copper oxide nanoparticles (CuONPs). Characterization of crude and calcined CuONPs was carried out by UV-vis spectroscopy, X-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy, zeta potential, dynamic light scattering, field emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. Afterward, biogenic CuONPs were evaluated for antibacterial, antioxidant, and cytotoxic effects using broth micro-dilution method, DPPH assay and alamarBlue assay, respectively. Finally, molecular mechanisms behind anticancer effects of CuONPs was ascertained by real time PCR. UV-vis absorbance spectra registered surface plasmon resonance peaks at 286 nm and 420 nm for crude and calcined CuONPs, respectively. FTIR spectra exhibited bands associated with organic functional groups of bacterial proteins, confirming capping and functionalization of CuONPs. The average crystallite size of crude and calcined CuONPs was determined as 18.24 and 21.3 nm by XRD, respectively. The average zeta potentials of crude and calcined CuONPs were as −28.57 ± 5.13 and −29.47 ± 4.78 mV, respectively, indicating their high stability. Electron microscopy revealed that crude and calcined CuONPs were roughly spherical particles with an average size of 35.24 ± 4.64 and 43.68 ± 2.31 nm, respectively. Biogenic CuONPs induced antibacterial effects with minimal inhibitory concentrations ranging from 62.5 to 1,000 μg/ml against Gram-negative and Gram-positive strains. The antioxidant activity of crude and calcined CuONPs was found to be 83% ± 2.64% and 78% ± 1.73%, respectively. More intriguingly, CuONPs exerted considerable cytotoxic effects on human colon and gastric adenocarcinoma cells, while induced low toxicity on normal cells. Anticancer effects of biogenic CuONPs were confirmed by significant changes induced in the expression of apoptosis-related genes, including P53, BAX, BCL2 and CCND1. Hence, biosynthesized CuONPs could be considered as potential antimicrobial, antioxidant and anticancer agents.

Synthesis and Characterization of Nanoparticles for Antimicrobial Applications-A Review

“…FT-IR spectroscopy is therefore a valuable tool for the characterization of the nanoparticles. In addition, FT-IR spectroscopy can be used to analyse bacterial biomolecules such as organic functional groups of bacterial proteins and further provide information on capping and functionization of the metal oxide nanoparticles, presented as an example in Figure 4 [196]. Conventional FT-IR spectrum is obtained from a sample which has been derivatized with potassium bromide (KBr).…”

A comparative study of the biosynthesis of CuNPs by Niallia circulans G9 and Paenibacillus sp. S4c strains: characterization and application as antimicrobial agents

“…ZTB29 [ 19 ], Morgenella species [ 20 ], Stenotrophomonas sp. BS95 [ 21 ] are also some examples for the bacteria that are able to synthesis CuNPs.…”

Biosynthesis of Artemisia abyssinica Leaf Extract-Mediated Bimetallic ZnO–CuO Nanoparticles: Antioxidant, Anticancer, and Molecular Docking Studies

“…The anticancer mechanism of CuO NPs is mainly through genotoxicity and apoptotic death in cancerous cells due to their ability to generate enhanced ROS . Moreover, the ZnO and CuO NPs have been also repeatedly reported as significant antioxidant agents. ,, However, due to their enhanced synergistic effects, including enriched surface area, multiple reactive sites, higher charge flow, and mass transfer, the integration of ZnO and CuO NPs together is preferred over their monometallic counterparts. ,, …”

“…Due to the stated constraints of conventional methods, the researchers paved the way for a new approach with less energy, time, and cost demands. The biological (green) synthesis approach is cost-effective, facile, and eco-benign and also prohibits the immersion of toxic chemicals into living entities. , The biosynthesis of MO NPs has been employed using diverse biosystems, such as plant extracts, bacteria, fungi, and large biological molecules. However, using plant extracts has a low handling cost, safer, and is an easy technique to fabricate NPs on a large scale in comparison with bacterial and fungal strains. , Furthermore, the multifarious functional groups from phytochemicals of plant extracts, counting NH 2 , SH, COOH, CO, and OH, are used as greener and stronger reducing and capping agents. , Using medicinal plants for the synthesis of NPs can also exhibit further synergistic effects on biological activity. , …”

“…However, due to their cost-effectiveness, structural activity, biocompatibility, and bioavailability, ZnO and CuO NPs have received special aspects among the various MO NPs in cancer and oxidative stress-induced ailments. , Owing to their surface crystal defects and semiconductive nature of these nanoparticles, the electrons move easily and could react with oxygen species to form free radicals, which in turn cause oxidative stress in cancerous cells. , Because of their inherent electrostatic nature and selective toxicity, ZnO NPs are more apposite in cancer therapy . ZnO nanoparticles have exhibited significant anticancer efficacies against a variety of cancer types, including lung cancer, breast cancer, ovarian cancer, and colorectal cancer .…”