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Carvacrol and Thymol Combat Desiccation Resistance Mechanisms in Salmonella enterica Serovar Tennessee

Some Salmonella enterica serovars are frequently associated with disease outbreaks in low-moisture foods (LMF) due to their ability to adapt efficiently to desiccation stress. These serovars are often persistent during food processing. Disruption of these resistance responses was accomplished previo...

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Autores principales: Abdelhamid, Ahmed G., Yousef, Ahmed E.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8779931/
https://www.ncbi.nlm.nih.gov/pubmed/35056493
http://dx.doi.org/10.3390/microorganisms10010044
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author Abdelhamid, Ahmed G.
Yousef, Ahmed E.
author_facet Abdelhamid, Ahmed G.
Yousef, Ahmed E.
author_sort Abdelhamid, Ahmed G.
collection PubMed
description Some Salmonella enterica serovars are frequently associated with disease outbreaks in low-moisture foods (LMF) due to their ability to adapt efficiently to desiccation stress. These serovars are often persistent during food processing. Disruption of these resistance responses was accomplished previously using the membrane-active lipopeptide, paenibacterin. This study was initiated to determine how desiccation resistance mechanisms are overcome when Salmonella Tennessee, a known resistant serovar, is treated with the membrane-active food additives carvacrol and thymol. Knowing that the minimum inhibitory concentrations (MICs) of carvacrol and thymol against Salmonella Tennessee are 200 and 100 µg/mL, the concentrations tested were 100–400 and 50–200 µg/mL, respectively. Results show that desiccation-adapted Salmonella Tennessee, prepared by air drying at 40% relative humidity and 22–25 °C for 24 h, was not inactivated when exposed for 4.0 h to less than 2xMIC of the two additives. Additionally, treatment of desiccation-adapted Salmonella Tennessee for 120 min with carvacrol and thymol at the MIC-level sensitized the cells (1.4–1.5 log CFU/mL reduction) to further desiccation stress. Treating desiccation-adapted Salmonella Tennessee with carvacrol and thymol induced leakage of intracellular potassium ions, reduced the biosynthesis of the osmoprotectant trehalose, reduced respiratory activity, decreased ATP production, and caused leakage of intracellular proteins and nucleic acids. Carvacrol, at 200–400 µg/mL, significantly downregulated the transcription of desiccation-related genes (proV, STM1494, and kdpA) as determined by the reverse-transcription quantitative PCR. The current study revealed some of the mechanisms by which carvacrol and thymol combat desiccation-resistant Salmonella Tennessee, raising the feasibility of using these additives to control desiccation-adapted S. enterica in LMF.
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spelling pubmed-87799312022-01-22 Carvacrol and Thymol Combat Desiccation Resistance Mechanisms in Salmonella enterica Serovar Tennessee Abdelhamid, Ahmed G. Yousef, Ahmed E. Microorganisms Article Some Salmonella enterica serovars are frequently associated with disease outbreaks in low-moisture foods (LMF) due to their ability to adapt efficiently to desiccation stress. These serovars are often persistent during food processing. Disruption of these resistance responses was accomplished previously using the membrane-active lipopeptide, paenibacterin. This study was initiated to determine how desiccation resistance mechanisms are overcome when Salmonella Tennessee, a known resistant serovar, is treated with the membrane-active food additives carvacrol and thymol. Knowing that the minimum inhibitory concentrations (MICs) of carvacrol and thymol against Salmonella Tennessee are 200 and 100 µg/mL, the concentrations tested were 100–400 and 50–200 µg/mL, respectively. Results show that desiccation-adapted Salmonella Tennessee, prepared by air drying at 40% relative humidity and 22–25 °C for 24 h, was not inactivated when exposed for 4.0 h to less than 2xMIC of the two additives. Additionally, treatment of desiccation-adapted Salmonella Tennessee for 120 min with carvacrol and thymol at the MIC-level sensitized the cells (1.4–1.5 log CFU/mL reduction) to further desiccation stress. Treating desiccation-adapted Salmonella Tennessee with carvacrol and thymol induced leakage of intracellular potassium ions, reduced the biosynthesis of the osmoprotectant trehalose, reduced respiratory activity, decreased ATP production, and caused leakage of intracellular proteins and nucleic acids. Carvacrol, at 200–400 µg/mL, significantly downregulated the transcription of desiccation-related genes (proV, STM1494, and kdpA) as determined by the reverse-transcription quantitative PCR. The current study revealed some of the mechanisms by which carvacrol and thymol combat desiccation-resistant Salmonella Tennessee, raising the feasibility of using these additives to control desiccation-adapted S. enterica in LMF. MDPI 2021-12-26 /pmc/articles/PMC8779931/ /pubmed/35056493 http://dx.doi.org/10.3390/microorganisms10010044 Text en © 2021 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Abdelhamid, Ahmed G.
Yousef, Ahmed E.
Carvacrol and Thymol Combat Desiccation Resistance Mechanisms in Salmonella enterica Serovar Tennessee
title Carvacrol and Thymol Combat Desiccation Resistance Mechanisms in Salmonella enterica Serovar Tennessee
title_full Carvacrol and Thymol Combat Desiccation Resistance Mechanisms in Salmonella enterica Serovar Tennessee
title_fullStr Carvacrol and Thymol Combat Desiccation Resistance Mechanisms in Salmonella enterica Serovar Tennessee
title_full_unstemmed Carvacrol and Thymol Combat Desiccation Resistance Mechanisms in Salmonella enterica Serovar Tennessee
title_short Carvacrol and Thymol Combat Desiccation Resistance Mechanisms in Salmonella enterica Serovar Tennessee
title_sort carvacrol and thymol combat desiccation resistance mechanisms in salmonella enterica serovar tennessee
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8779931/
https://www.ncbi.nlm.nih.gov/pubmed/35056493
http://dx.doi.org/10.3390/microorganisms10010044
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