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Title: A morphological study of the changes in the ultrastructure of a bacterial biofilm disrupted by an ac corona discharge in air

Abstract

The morphology of bacterial cells and biofilms subjected to a low frequency (∼10{sup 5} Hz) ac (∼10{sup −1} A) corona discharge was investigated using electron microscopy. A low-frequency ac corona discharge in air is shown to have a bactericidal and bacteriostatic effect on Escherichia coli M17 culture at both the cellular and population levels. Corona exposure inhibits the formation of a microbial community and results in the destruction of formed biofilms. This paper presents data on changes in the ultrastructure of cells and biofilms after corona treatment. Our results suggest that the E. coli M17 cells inside biofilms are affected with results similar to sub-lethal and lethal thermal exposure. Some of the biological aspects of colony and biofilm cells death are evaluated. Morphological changes in the ultrastructure of the biofilms under corona treatment are described. Our results indicate that the heating effect is the main factor responsible for the corona-induced inactivation of bacteria.

Authors:
; ;  [1]; ; ;  [2]
  1. Physical Faculty, Saint Petersburg State University, St. Petersburg (Russian Federation)
  2. Faculty of Medicine, Saint Petersburg State University, St. Petersburg (Russian Federation)
Publication Date:
OSTI Identifier:
22597666
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AIR; CORONA DISCHARGES; ELECTRON MICROSCOPY; ELECTRONS; ESCHERICHIA COLI; HEATING; INACTIVATION; MORPHOLOGICAL CHANGES; MORPHOLOGY

Citation Formats

Stepanova, Olga, E-mail: o.m.stepanova@spbu.ru, Astafiev, Alexander, Kudryavtsev, Anatoly, Rybalchenko, Oksana, Orlova, Olga, and Kapustina, Valentina. A morphological study of the changes in the ultrastructure of a bacterial biofilm disrupted by an ac corona discharge in air. United States: N. p., 2016. Web. doi:10.1063/1.4959992.
Stepanova, Olga, E-mail: o.m.stepanova@spbu.ru, Astafiev, Alexander, Kudryavtsev, Anatoly, Rybalchenko, Oksana, Orlova, Olga, & Kapustina, Valentina. A morphological study of the changes in the ultrastructure of a bacterial biofilm disrupted by an ac corona discharge in air. United States. doi:10.1063/1.4959992.
Stepanova, Olga, E-mail: o.m.stepanova@spbu.ru, Astafiev, Alexander, Kudryavtsev, Anatoly, Rybalchenko, Oksana, Orlova, Olga, and Kapustina, Valentina. 2016. "A morphological study of the changes in the ultrastructure of a bacterial biofilm disrupted by an ac corona discharge in air". United States. doi:10.1063/1.4959992.
@article{osti_22597666,
title = {A morphological study of the changes in the ultrastructure of a bacterial biofilm disrupted by an ac corona discharge in air},
author = {Stepanova, Olga, E-mail: o.m.stepanova@spbu.ru and Astafiev, Alexander and Kudryavtsev, Anatoly and Rybalchenko, Oksana and Orlova, Olga and Kapustina, Valentina},
abstractNote = {The morphology of bacterial cells and biofilms subjected to a low frequency (∼10{sup 5} Hz) ac (∼10{sup −1} A) corona discharge was investigated using electron microscopy. A low-frequency ac corona discharge in air is shown to have a bactericidal and bacteriostatic effect on Escherichia coli M17 culture at both the cellular and population levels. Corona exposure inhibits the formation of a microbial community and results in the destruction of formed biofilms. This paper presents data on changes in the ultrastructure of cells and biofilms after corona treatment. Our results suggest that the E. coli M17 cells inside biofilms are affected with results similar to sub-lethal and lethal thermal exposure. Some of the biological aspects of colony and biofilm cells death are evaluated. Morphological changes in the ultrastructure of the biofilms under corona treatment are described. Our results indicate that the heating effect is the main factor responsible for the corona-induced inactivation of bacteria.},
doi = {10.1063/1.4959992},
journal = {Journal of Applied Physics},
number = 6,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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