Advanced Killing Potential of Thymol against a Time and Temperature Optimized Attached <i>Listeria monocytogenes</i> Population in Lettuce Broth
Fresh vegetables and salads are increasingly implicated in outbreaks of foodborne infections, such as those caused by <i>Listeria monocytogenes</i>, a dangerous pathogen that can attach to the surfaces of the equipment creating robust biofilms withstanding the killing action of disinfect...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-03-01
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| Series: | Biomolecules |
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| Online Access: | https://www.mdpi.com/2218-273X/11/3/397 |
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| author | Dimitra Kostoglou Parthena Tsaklidou Ioannis Iliadis Nikoletta Garoufallidou Georgia Skarmoutsou Ioannis Koulouris Efstathios Giaouris |
| author_facet | Dimitra Kostoglou Parthena Tsaklidou Ioannis Iliadis Nikoletta Garoufallidou Georgia Skarmoutsou Ioannis Koulouris Efstathios Giaouris |
| author_sort | Dimitra Kostoglou |
| collection | DOAJ |
| description | Fresh vegetables and salads are increasingly implicated in outbreaks of foodborne infections, such as those caused by <i>Listeria monocytogenes</i>, a dangerous pathogen that can attach to the surfaces of the equipment creating robust biofilms withstanding the killing action of disinfectants. In this study, the antimicrobial efficiency of a natural plant terpenoid (thymol) was evaluated against a sessile population of a multi-strain <i>L. monocytogenes</i> cocktail developed on stainless steel surfaces incubated in lettuce broth, under optimized time and temperature conditions (54 h at 30.6 °C) as those were determined following response surface modeling, and in comparison, to that of an industrial disinfectant (benzalkonium chloride). Prior to disinfection, the minimum bactericidal concentrations (MBCs) of each compound were determined against the planktonic cells of each strain. The results revealed the advanced killing potential of thymol, with a concentration of 625 ppm (= 4 × MBC) leading to almost undetectable viable bacteria (more than 4 logs reduction following a 15-min exposure). For the same degree of killing, benzalkonium chloride needed to be used at a concentration of at least 20 times more than its MBC (70 ppm). Discriminative repetitive sequence-based polymerase chain reaction (rep-PCR) also highlighted the strain variability in both biofilm formation and resistance. In sum, thymol was found to present an effective anti-listeria action under environmental conditions mimicking those encountered in the salad industry and deserves to be further explored to improve the safety of fresh produce. |
| first_indexed | 2024-03-09T05:00:46Z |
| format | Article |
| id | doaj.art-18946dcda0da4b2fa16f968ffd7453f5 |
| institution | Directory Open Access Journal |
| issn | 2218-273X |
| language | English |
| last_indexed | 2024-03-09T05:00:46Z |
| publishDate | 2021-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Biomolecules |
| spelling | doaj.art-18946dcda0da4b2fa16f968ffd7453f52023-12-03T12:59:48ZengMDPI AGBiomolecules2218-273X2021-03-0111339710.3390/biom11030397Advanced Killing Potential of Thymol against a Time and Temperature Optimized Attached <i>Listeria monocytogenes</i> Population in Lettuce BrothDimitra Kostoglou0Parthena Tsaklidou1Ioannis Iliadis2Nikoletta Garoufallidou3Georgia Skarmoutsou4Ioannis Koulouris5Efstathios Giaouris6Laboratory of Food Microbiology and Hygiene, Department of Food Science and Nutrition, School of the Environment, University of the Aegean, 81400 Myrina, Lemnos, GreeceLaboratory of Food Microbiology and Hygiene, Department of Food Science and Nutrition, School of the Environment, University of the Aegean, 81400 Myrina, Lemnos, GreeceLaboratory of Food Microbiology and Hygiene, Department of Food Science and Nutrition, School of the Environment, University of the Aegean, 81400 Myrina, Lemnos, GreeceLaboratory of Food Microbiology and Hygiene, Department of Food Science and Nutrition, School of the Environment, University of the Aegean, 81400 Myrina, Lemnos, GreeceLaboratory of Food Microbiology and Hygiene, Department of Food Science and Nutrition, School of the Environment, University of the Aegean, 81400 Myrina, Lemnos, GreeceLaboratory of Food Microbiology and Hygiene, Department of Food Science and Nutrition, School of the Environment, University of the Aegean, 81400 Myrina, Lemnos, GreeceLaboratory of Food Microbiology and Hygiene, Department of Food Science and Nutrition, School of the Environment, University of the Aegean, 81400 Myrina, Lemnos, GreeceFresh vegetables and salads are increasingly implicated in outbreaks of foodborne infections, such as those caused by <i>Listeria monocytogenes</i>, a dangerous pathogen that can attach to the surfaces of the equipment creating robust biofilms withstanding the killing action of disinfectants. In this study, the antimicrobial efficiency of a natural plant terpenoid (thymol) was evaluated against a sessile population of a multi-strain <i>L. monocytogenes</i> cocktail developed on stainless steel surfaces incubated in lettuce broth, under optimized time and temperature conditions (54 h at 30.6 °C) as those were determined following response surface modeling, and in comparison, to that of an industrial disinfectant (benzalkonium chloride). Prior to disinfection, the minimum bactericidal concentrations (MBCs) of each compound were determined against the planktonic cells of each strain. The results revealed the advanced killing potential of thymol, with a concentration of 625 ppm (= 4 × MBC) leading to almost undetectable viable bacteria (more than 4 logs reduction following a 15-min exposure). For the same degree of killing, benzalkonium chloride needed to be used at a concentration of at least 20 times more than its MBC (70 ppm). Discriminative repetitive sequence-based polymerase chain reaction (rep-PCR) also highlighted the strain variability in both biofilm formation and resistance. In sum, thymol was found to present an effective anti-listeria action under environmental conditions mimicking those encountered in the salad industry and deserves to be further explored to improve the safety of fresh produce.https://www.mdpi.com/2218-273X/11/3/397<i>Listeria monocytogenes</i>attachmentstainless steellettucedisinfectionthymol |
| spellingShingle | Dimitra Kostoglou Parthena Tsaklidou Ioannis Iliadis Nikoletta Garoufallidou Georgia Skarmoutsou Ioannis Koulouris Efstathios Giaouris Advanced Killing Potential of Thymol against a Time and Temperature Optimized Attached <i>Listeria monocytogenes</i> Population in Lettuce Broth Biomolecules <i>Listeria monocytogenes</i> attachment stainless steel lettuce disinfection thymol |
| title | Advanced Killing Potential of Thymol against a Time and Temperature Optimized Attached <i>Listeria monocytogenes</i> Population in Lettuce Broth |
| title_full | Advanced Killing Potential of Thymol against a Time and Temperature Optimized Attached <i>Listeria monocytogenes</i> Population in Lettuce Broth |
| title_fullStr | Advanced Killing Potential of Thymol against a Time and Temperature Optimized Attached <i>Listeria monocytogenes</i> Population in Lettuce Broth |
| title_full_unstemmed | Advanced Killing Potential of Thymol against a Time and Temperature Optimized Attached <i>Listeria monocytogenes</i> Population in Lettuce Broth |
| title_short | Advanced Killing Potential of Thymol against a Time and Temperature Optimized Attached <i>Listeria monocytogenes</i> Population in Lettuce Broth |
| title_sort | advanced killing potential of thymol against a time and temperature optimized attached i listeria monocytogenes i population in lettuce broth |
| topic | <i>Listeria monocytogenes</i> attachment stainless steel lettuce disinfection thymol |
| url | https://www.mdpi.com/2218-273X/11/3/397 |
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