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Effects of High Hydrostatic Pressure on Escherichia coli Ultrastructure, Membrane Integrity and Molecular Composition as Assessed by FTIR Spectroscopy and Microscopic Imaging Techniques
High hydrostatic pressure (HHP) is a novel food processing technology that is considered as an attractive alternative to conventional heat treatments for the preservation of foods, due to its lethal effects on pathogenic and spoilage microorganisms, while causing minor effects on food quality and se...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2014
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6271356/ https://www.ncbi.nlm.nih.gov/pubmed/25529018 http://dx.doi.org/10.3390/molecules191221310 |
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author | Prieto-Calvo, María Prieto, Miguel López, Mercedes Alvarez-Ordóñez, Avelino |
author_facet | Prieto-Calvo, María Prieto, Miguel López, Mercedes Alvarez-Ordóñez, Avelino |
author_sort | Prieto-Calvo, María |
collection | PubMed |
description | High hydrostatic pressure (HHP) is a novel food processing technology that is considered as an attractive alternative to conventional heat treatments for the preservation of foods, due to its lethal effects on pathogenic and spoilage microorganisms, while causing minor effects on food quality and sensorial attributes. This study is aimed at investigating how HHP treatments at varying intensities in the range 50–900 MPa affect the viability, membrane integrity, ultrastructure and molecular composition of Escherichia coli. Results of membrane integrity tests (measurement of cellular leakage and monitoring of propidium iodide uptake through fluorescence microscopy) and ultrastructural observations by transmission electron microscopy demonstrated that HHP gave rise to cellular enlargement, membrane damage or detachment, DNA and protein denaturation and loss of intracellular contents. Fourier-transform infrared (FTIR) spectroscopy analyses evidenced minor changes in molecular composition in response to high pressures, which were mostly observed on the spectral region w(4) (1200–900 cm(−1)), mainly informative of carbohydrates and polysaccharides of the cell wall. These findings suggest that exposure of E. coli cells to HHP causes alterations in their physical integrity while producing minor modifications in biochemical cellular composition. The current study increases the knowledge on the mechanisms of E. coli inactivation by HHP and provides valuable information for the design of more effective food preservation regimes based on the integration of mild HHP in combination with other food preservation strategies into a multi-target hurdle technology approach. |
format | Online Article Text |
id | pubmed-6271356 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2014 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-62713562018-12-28 Effects of High Hydrostatic Pressure on Escherichia coli Ultrastructure, Membrane Integrity and Molecular Composition as Assessed by FTIR Spectroscopy and Microscopic Imaging Techniques Prieto-Calvo, María Prieto, Miguel López, Mercedes Alvarez-Ordóñez, Avelino Molecules Article High hydrostatic pressure (HHP) is a novel food processing technology that is considered as an attractive alternative to conventional heat treatments for the preservation of foods, due to its lethal effects on pathogenic and spoilage microorganisms, while causing minor effects on food quality and sensorial attributes. This study is aimed at investigating how HHP treatments at varying intensities in the range 50–900 MPa affect the viability, membrane integrity, ultrastructure and molecular composition of Escherichia coli. Results of membrane integrity tests (measurement of cellular leakage and monitoring of propidium iodide uptake through fluorescence microscopy) and ultrastructural observations by transmission electron microscopy demonstrated that HHP gave rise to cellular enlargement, membrane damage or detachment, DNA and protein denaturation and loss of intracellular contents. Fourier-transform infrared (FTIR) spectroscopy analyses evidenced minor changes in molecular composition in response to high pressures, which were mostly observed on the spectral region w(4) (1200–900 cm(−1)), mainly informative of carbohydrates and polysaccharides of the cell wall. These findings suggest that exposure of E. coli cells to HHP causes alterations in their physical integrity while producing minor modifications in biochemical cellular composition. The current study increases the knowledge on the mechanisms of E. coli inactivation by HHP and provides valuable information for the design of more effective food preservation regimes based on the integration of mild HHP in combination with other food preservation strategies into a multi-target hurdle technology approach. MDPI 2014-12-18 /pmc/articles/PMC6271356/ /pubmed/25529018 http://dx.doi.org/10.3390/molecules191221310 Text en © 2014 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Prieto-Calvo, María Prieto, Miguel López, Mercedes Alvarez-Ordóñez, Avelino Effects of High Hydrostatic Pressure on Escherichia coli Ultrastructure, Membrane Integrity and Molecular Composition as Assessed by FTIR Spectroscopy and Microscopic Imaging Techniques |
title | Effects of High Hydrostatic Pressure on Escherichia coli Ultrastructure, Membrane Integrity and Molecular Composition as Assessed by FTIR Spectroscopy and Microscopic Imaging Techniques |
title_full | Effects of High Hydrostatic Pressure on Escherichia coli Ultrastructure, Membrane Integrity and Molecular Composition as Assessed by FTIR Spectroscopy and Microscopic Imaging Techniques |
title_fullStr | Effects of High Hydrostatic Pressure on Escherichia coli Ultrastructure, Membrane Integrity and Molecular Composition as Assessed by FTIR Spectroscopy and Microscopic Imaging Techniques |
title_full_unstemmed | Effects of High Hydrostatic Pressure on Escherichia coli Ultrastructure, Membrane Integrity and Molecular Composition as Assessed by FTIR Spectroscopy and Microscopic Imaging Techniques |
title_short | Effects of High Hydrostatic Pressure on Escherichia coli Ultrastructure, Membrane Integrity and Molecular Composition as Assessed by FTIR Spectroscopy and Microscopic Imaging Techniques |
title_sort | effects of high hydrostatic pressure on escherichia coli ultrastructure, membrane integrity and molecular composition as assessed by ftir spectroscopy and microscopic imaging techniques |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6271356/ https://www.ncbi.nlm.nih.gov/pubmed/25529018 http://dx.doi.org/10.3390/molecules191221310 |
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