Effect of CuO Nanoparticles over Isolated Bacterial Strains from Agricultural Soil

Abstract

The increased use of the nanoparticles (NPs) on several processes is notorious. In contrast the ecotoxicological effects of NPs have been scarcely studied. The main current researches are related to the oxide metallic NPs. In the present work, fifty-six bacterial strains were isolated from soil, comprising 17 different OTUs distributed into 3 classes: Bacilli (36 strains), Flavobacteria (2 strains), and Gammaproteobacteria (18 strains). Copper oxide nanoparticles (CuONPs) were synthesized using a process of chemical precipitation. The obtained CuONPs have a spherical shape and primary size less than 17 nm. Twenty-one strains were used to evaluate the cytotoxicity of CuONPs and 11 of these strains showed high sensibility. Among those 11 strains, 4 (Brevibacillus laterosporusstrain CSS8,Chryseobacterium indoltheticumstrain CSA28, andPantoea ananatisstrains CSA34 and CSA35) were selected to determine the kind of damage produced. The CuONPs toxic effect was observed at expositions over 25 mg·L−1and the damage to cell membrane above 160 mg·L−1. The electron microscopy showed the formation of cavities, holes, membrane degradation, blebs, cellular collapse, and lysis. These toxic effects may probably be due to the ions interaction, the oxide-reduction reactions, and the generation of reactive species.

Tunable electrochemistry and efficient antibacterial activity of plant-mediated copper oxide nanoparticles synthesized by Annona squamosa seed extract for agricultural utility

“…CuO NPs were previously shown to interact with the plasma membrane of bacteria, leading to holes in the membrane and the lysis of bacterial cell. 29 The released Cu 2+ ions were also found to interact with negatively charged components of the cell wall and membrane, leading to denaturation and alteration of the membrane proteins. 30 Copper ions inside the bacterial cell generate ROS, leading to alterations in cellular signalling and interfering with the nucleic acid, resulting in an altered helical structure.…”

Antibacterial activity of colloidal copper nanoparticles against Gram-negative (Escherichia coli and Proteus vulgaris) bacteria

“…Literature reports have suggested that antibacterial activities of CuNPs lead to rapid DNA degradation and reduction of bacterial respiration (Concha‐Guerrero et al . 2014). Other possible antibacterial mechanism involves elution of Cu 2+ ions from nanoparticles, which easily gets absorbed on bacterial cell membrane and damages the membrane either by altering their enzyme functions or by solidifying proteins (Raffi et al .…”

“…Copper ions released from CuNPs have grater affinity towards these groups leading to alteration of membrane proteins, electron transport chain and inhibition of cytochromes of Gram-negative cell membranes (Orell et al 2010). Literature reports have suggested that antibacterial activities of CuNPs lead to rapid DNA degradation and reduction of bacterial respiration (Concha-Guerrero et al 2014). Other possible antibacterial mechanism involves elution of Cu 2+ ions from nanoparticles, which easily gets absorbed on bacterial cell membrane and damages the membrane either by altering their enzyme functions or by solidifying proteins (Raffi et al 2010;Slavin et al 2017).…”

Effect of organic and conventional farming on soil bacterial diversity of pecan tree ( Carya illinoensis K. Kosh) orchard across two phenological stages

“…Although the bacterial community analyses were performed for composite samples to take into account the heterogeneity, the analysis provided accurate information as previously reported for other studies (Concha‐Guerrero et al . 2015; Liu et al . 2015).…”