{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T14:20:59Z","timestamp":1763389259698,"version":"build-2065373602"},"reference-count":44,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2019,10,23]],"date-time":"2019-10-23T00:00:00Z","timestamp":1571788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"This research received in part funding by the Ministry of Education, University and Research (MIUR), Ricerca Scientifica Finanziata, University of Turin (Italy).","award":["(ex 60%) - Year 2017"],"award-info":[{"award-number":["(ex 60%) - Year 2017"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The aim of this study was to evaluate the influence of tea tree oil (TTO) and \u201cMentha of Pancalieri\u201d essential oil (MPP) on intracellular killing of Candida krusei, often resistant to conventional drugs, by polymorphonuclear leucocytes (PMNs). Intracellular killing was investigated by incubating yeasts and PMNs with essential oils (EOs) at 1\/4 and 1\/8 \u00d7 MIC (Minimal Inhibitory Concentration), in comparison with anidulafungin, used as a reference drug. Killing values were expressed as Survival Index (SI) values. The cytotoxicity of EOs was evaluated by 3-[4,-5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Both EOs were more efficaceous at 1\/8 \u00d7 MIC than 1\/4 \u00d7 MIC, with killing values higher than observed in EO-free systems and in presence of anidulafungin, indicating that the decreasing concentrations did not cause lower candidacidal activity. This better activity at 1\/8 \u00d7 MIC is probably due to the EOs\u2019 toxicity at 1\/4 \u00d7 MIC, suggesting that at higher concentrations EOs might interfere with PMNs functionality. TTO and MPP at 1\/8 \u00d7 MIC significantly increased intracellular killing by PMNs through their direct action on the yeasts (both EOs) or on phagocytic cells (MPP), suggesting a positive interaction between EOs and PMNs to eradicate intracellular C. krusei. These data showed a promising potential application of TTO and \u201cMentha of Pancalieri\u201d EO as natural adjuvants in C. krusei infection management.<\/jats:p>","DOI":"10.3390\/molecules24213824","type":"journal-article","created":{"date-parts":[[2019,10,25]],"date-time":"2019-10-25T03:20:36Z","timestamp":1571973636000},"page":"3824","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Enhanced Killing of Candida krusei by Polymorphonuclear Leucocytes in the Presence of Subinhibitory Concentrations of Melaleuca alternifolia and \u201cMentha of Pancalieri\u201d Essential Oils"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8660-4248","authenticated-orcid":false,"given":"Vivian","family":"Tullio","sequence":"first","affiliation":[{"name":"Dept. Public Health and Pediatrics, Microbiology Division, University of Turin, 10126 Turin, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2542-622X","authenticated-orcid":false,"given":"Janira","family":"Roana","sequence":"additional","affiliation":[{"name":"Dept. Public Health and Pediatrics, Microbiology Division, University of Turin, 10126 Turin, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8684-3804","authenticated-orcid":false,"given":"Daniela","family":"Scalas","sequence":"additional","affiliation":[{"name":"Area Servizi Alla Ricerca Polo Agraria e Medicina Veterinaria, University of Turin, 10095 Turin, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2949-4556","authenticated-orcid":false,"given":"Narcisa","family":"Mandras","sequence":"additional","affiliation":[{"name":"Dept. Public Health and Pediatrics, Microbiology Division, University of Turin, 10126 Turin, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"594","DOI":"10.3109\/1040841X.2014.974500","article-title":"Novel strategies to fight Candida infection","volume":"42","author":"Rodrigues","year":"2016","journal-title":"Crit. Rev. Microbiol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3012462","DOI":"10.1155\/2016\/3012462","article-title":"Antimicrobial properties of plant essential oils against human pathogens and their mode of action: An updated review","volume":"2016","author":"Swamy","year":"2016","journal-title":"Evid. Based Complement. Altern. 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