{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,26]],"date-time":"2025-09-26T00:21:43Z","timestamp":1758846103482,"version":"3.44.0"},"reference-count":42,"publisher":"Public Library of Science (PLoS)","issue":"9","license":[{"start":{"date-parts":[[2025,9,25]],"date-time":"2025-09-25T00:00:00Z","timestamp":1758758400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/publicdomain\/zero\/1.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p><jats:italic><jats:italic>Salmonella<\/jats:italic><\/jats:italic> spp., a major cause of foodborne illness, requires effective control strategies to improve food safety. Thymol, an antibacterial agent derived from natural essential oils, has been assessed for use as an antimicrobial agent and preservative in the food industry, due to its safety and low cost. This study used flow cytometry and Tryptic Soy Agar (TSA) plate counts, to assess the viability of five serotypes of <jats:italic><jats:italic>Salmonella enterica<\/jats:italic><\/jats:italic> subsp. <jats:italic><jats:italic>enterica<\/jats:italic><\/jats:italic> over 56 days in thymol at 4\u00b0C and 25\u00b0C, during long-term storage in distilled water. The minimum inhibitory concentration (MIC) of thymol against <jats:italic><jats:italic>Salmonella<\/jats:italic><\/jats:italic> serotypes was found to be 256 \u00b5g\/mL at both 25\u00b0C and 4\u00b0C for all serotypes at the initial time point (day 0) and after 154 days of incubation in water. Flow cytometry successfully counted viable cells in the control group, which contained 2% ethanol and 128 \u00b5g\/mL thymol. However, plate count numbers completely declined after day 7 at both 25\u00b0C and 4\u00b0C for all thymol concentrations. After exposure to sub-MIC levels and subsequent spiking with 256 \u00b5g\/mL at 25\u00b0C and 4\u00b0C, neither flow cytometry nor plate counts detected viable cells. These findings emphasize the importance of advanced techniques such as flow cytometry for the detection of microorganisms and demonstrate thymol\u2019s potential as an environmentally friendly solution in food safety strategies to reduce <jats:italic><jats:italic>Salmonella<\/jats:italic><\/jats:italic> contamination in water sources over extended periods.<\/jats:p>","DOI":"10.1371\/journal.pone.0332053","type":"journal-article","created":{"date-parts":[[2025,9,25]],"date-time":"2025-09-25T17:28:36Z","timestamp":1758821316000},"page":"e0332053","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Examining the viability of five Salmonella enterica subsp. enterica in thymol at 4\u00b0C and 25\u00b0C using flow cytometry"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0102-3007","authenticated-orcid":true,"given":"Anna","family":"Williams","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Soumana","family":"Daddy Gaoh","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8325-9955","authenticated-orcid":true,"given":"Pierre","family":"Alusta","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Angel","family":"Paredes","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alena","family":"Savenka","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4904-7577","authenticated-orcid":true,"given":"Dan A.","family":"Buzatu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8849-5006","authenticated-orcid":true,"given":"Youngbeom","family":"Ahn","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2025,9,25]]},"reference":[{"key":"pone.0332053.ref001","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1016\/j.fm.2018.10.009","article-title":"Phages for biocontrol in foods: What opportunities for Salmonella sp. control along the dairy food chain?","volume":"78","author":"V LeLi\u00e8vre","year":"2019","journal-title":"Food Microbiol"},{"issue":"4","key":"pone.0332053.ref002","doi-asserted-by":"crossref","first-page":"766","DOI":"10.1017\/S0950268816002867","article-title":"Antimicrobial resistance in Salmonella that caused foodborne disease outbreaks: United States, 2003-2012","volume":"145","author":"AC 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