Bacteria assisted green synthesis of copper oxide nanoparticles and their potential applications as antimicrobial agents and plant growth stimulants

Abstract

Copper oxide nanoparticles (CuO-NPs) have piqued the interest of agricultural researchers due to their potential application as fungicides, insecticides, and fertilizers. The Serratia sp. ZTB29 strain, which has the NCBI accession number MK773873, was a novel isolate used in this investigation that produced CuO-NPs. This strain can survive concentrations of copper as high as 22.5 mM and can also remove copper by synthesizing pure CuO-NPs. UV-VIS spectroscopy, DLS, Zeta potential, FTIR, TEM, and XRD techniques were used to investigate the pure form of CuO-NPs. The synthesized CuO-NPs were crystalline in nature (average size of 22 nm) with a monoclinic phase according to the XRD pattern. CuO-NPs were found to be polydisperse, spherical, and agglomeration-free. According to TEM and DLS inspection, they ranged in size from 20 to 40 nm, with a typical particle size of 28 nm. CuO-NPs were extremely stable, as demonstrated by their zeta potential of −15.4 mV. The ester (C=O), carboxyl (C=O), amine (NH), thiol (S-H), hydroxyl (OH), alkyne (C-H), and aromatic amine (C-N) groups from bacterial secretion were primarily responsible for reduction and stabilization of CuO-NPs revealed in an FTIR analysis. CuO-NPs at concentrations of 50 μg mL−1 and 200 μg mL−1 displayed antibacterial and antifungal activity against the plant pathogenic bacteria Xanthomonas sp. and pathogenic fungus Alternaria sp., respectively. The results of this investigation support the claims that CuO-NPs can be used as an efficient antimicrobial agent and nano-fertilizer, since, compared to the control and higher concentrations of CuO-NPs (100 mg L−1) considerably improved the growth characteristics of maize plants.

Nanoparticles as a Tool for Alleviating Plant Stress: Mechanisms, Implications, and Challenges

“…Consistent with this, another study on soybean reported the improvement of plant growth under copper stress mediated by release of nitric oxide by chitosan nanoparticles [ 105 ]. Similarly, considering the biocompatibility and antimicrobial properties of silver and copper, their nanoparticles have been widely used in the amelioration of various biotic stressors [ 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 , 116 , 117 , 118 , 119 , 120 , 121 , 122 , 123 , 124 , 125 ].…”

Eco-Friendly Cost-Effective Formation of Copper Oxide Nanostructures and its Prodigious Potential for Environmental Remediation Applications

“…The dried sample was grounded and calcined for three hours at 500°C. The material was granulated and placed in a container after it reached room temperature (Singh et al 2023) (Figure 1).…”

“…These dyes impede the flow of oxygen and light into water. Reactive black is a dye consumed extensively for reactive dying (Singh et al 2023).…”

Updates on Biogenic Metallic and Metal Oxide Nanoparticles: Therapy, Drug Delivery and Cytotoxicity

“…Biosynthesized CuO NPs have been prepared from leaf extract of Eucaliptus globulos [ 58 ], mint leaves and orange peels [ 59 ], algae ( Anabaena cylidrica ) [ 60 ], and bacteria ( Serratia sp.) [ 61 ], usually by using copper sulfate salt precursor. The biosynthesized CuO NPs are thought to have increased antimicrobial activity compared to commercial NPs due to the participation of natural extracts used for reduction [ 3 ].…”