Volume: 1, 2022
1st International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland: ENVIRONMENT – PLANT – ANIMAL – PRODUCT
Abstract number: T025
DOI: https://doi.org/10.24326/ICDSUPL1.T025
Published online: 26 April 2022
ICDSUPL, 1, T025 (2022)
Harmful effects of ZnONPs on Bacillus sp.
Katarzyna Magdalena Matyszczuk1*, Anna Krzepiłko1
11 Department of Biotechnology, Microbiology and Human Nutrition, Faculty of Food Sciences and Biotechnology, University of Life Sciences in Lublin, Skromna 8, 20-704, Lublin, Poland
* Corresponding author: katarzyna.matyszczuk@up.lublin.pl
Abstract
The bactericidal activity of metal nanoparticles is related to their pleiotropic effect on cells. The contact of metal nanoparticles with bacteria cells causes changes in the structure of the cell wall, the permeability of the cell membrane, and the destruction of organelles and lysis. Metal nanoparticles can also penetrate the cell membrane, release metal ions and produce reactive oxygen species that damage organelles and disturb intracellular metabolism. Zinc oxide nanoparticles (ZnONPs) are used in various industries, they are also very important in agriculture, as an additive to fertilizers and as a bactericide. Due to the penetration of nanoparticles into soils, ZnONPs has a toxic effect on the organisms living in it, including bacteria that promote plant growth. The aim of the work was to investigate the interaction of zinc oxide nanoparticles with Bacillus cells: B. thuringiensis, B. subtilis, B. megaterium, B. cereus, B. pumilis, B. amyloliquefaciens, and B. licheniformis. to see if there is a loss of membrane integrity. The extracellular release of nucleic acids and proteins from cells after incubation with various concentrations of ZnONPs in a concentration range of 0.2 to 1.4 mg/ml was quantified. In the culture was incubated with various ZnONPs concentrations, the protein was determined by the Bradford method [1967] and the nucleic acids by the method [Reddy et al. 2014]. Planktonic growth of cells growing in the presence of ZnONPs concentrations was monitored in the liquid medium in the stationary phase by measuring the OD of the culture. The oxidative stress was determined by measuring the reduction of NBT to formazan [Paździoch-Czochra 2003]. The addition of ZnONPs delayed planktonic growth of cells. A similar reaction of all tested Bacillus strains was observed, with increasing concentration of nanoparticles, the optical density of the culture decreased. Increased production of the superoxide radical anion dependent on the concentration of nanoparticles was noted for all Bacillus strains. A dose-dependent increase in the release of nucleic acids and proteins from bacterial cells was also found. This data confirms that the biocidal mechanism of action of ZnONPs, in the studied range, is associated with damage to the bacterial cell membrane, an increase in the membrane permeability, production of free radicals and consequently inhibiting the growth of Bacillus cultures.
How to cite
K.M. Matyszczuk, A. Krzepiłko, 2022. Harmful effects of ZnONPs on Bacillus sp. In: 1st International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL1/T025