{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T08:27:01Z","timestamp":1787128021429,"version":"build-2736575974"},"reference-count":45,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T00:00:00Z","timestamp":1787097600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Multidrug-resistant Acinetobacter baumannii isolates pose a threat to healthcare systems worldwide. The antibacterial activity of essential oil components (EOCs)\u2014linalool, geraniol, eugenol, citronellol, 1,8-cineole, carvacrol, and trans-anethole\u2014was evaluated both alone and in combinations against multidrug-resistant A. baumannii clinical strains from wound infections, and against two reference strains. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of EOCs were determined using the broth microdilution method. The interactions between EOCs were investigated using the checkerboard microdilution method. Carvacrol and eugenol showed the strongest inhibitory effects against the tested strains. The MICs and MBCs of carvacrol were 1.70\u20133.39 mg\/mL. The MICs of eugenol were 4.10\u201316.41 mg\/mL, while the MBCs were 4.10\u201332.81 mg\/mL. MIC\/MBC analysis showed that all tested EOCs had bactericidal activity against A. baumannii in vitro; however, some required higher concentrations. Most EOC mixtures showed synergistic interactions. The combination of eugenol and carvacrol induced the strongest synergistic effect, leading to the greatest reduction in the MICs of both compounds (MIC of carvacrol decreased by 8\u201330-fold, while the MIC of eugenol decreased by 16\u201364-fold). Our results indicate that some EOCs, especially when combined, exhibit significant antibacterial activity against A. baumannii.<\/jats:p>","DOI":"10.3390\/molecules31162888","type":"journal-article","created":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T07:58:23Z","timestamp":1787126303000},"page":"2888","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["In Vitro Synergistic Effects of Selected Essential Oil Components Against Clinical Acinetobacter baumannii Strains"],"prefix":"10.3390","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1986-2220","authenticated-orcid":false,"given":"Magdalena","family":"Szemraj","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Microbiology and Microbiological Diagnostics, Medical University of Lodz, 90-419 \u0141\u00f3d\u017a, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barbara","family":"Kot","sequence":"additional","affiliation":[{"name":"Institute of Biological Sciences, Faculty of Exact and Natural Sciences, University of Siedlce, 14 Boles\u0142awa Prusa Str., 08-110 Siedlce, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kamila","family":"Olszowiec","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Microbiology and Microbiological Diagnostics, Medical University of Lodz, 90-419 \u0141\u00f3d\u017a, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zuzanna","family":"Walczak","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Microbiology and Microbiological Diagnostics, Medical University of Lodz, 90-419 \u0141\u00f3d\u017a, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ma\u0142gorzata","family":"Piechota","sequence":"additional","affiliation":[{"name":"Institute of Biological Sciences, Faculty of Exact and Natural Sciences, University of Siedlce, 14 Boles\u0142awa Prusa Str., 08-110 Siedlce, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3631-4701","authenticated-orcid":false,"given":"Ma\u0142gorzata","family":"Witeska","sequence":"additional","affiliation":[{"name":"Department of Animal Environment Biology, Institute of Animal Science, Warsaw University of Life Sciences\u2014SGGW, Ciszewskiego 8, 02-786 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9823-4176","authenticated-orcid":false,"given":"Monika","family":"Sienkiewicz","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Microbiology and Microbiological Diagnostics, Medical University of Lodz, 90-419 \u0141\u00f3d\u017a, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"107605","DOI":"10.1016\/j.micpath.2025.107605","article-title":"Acinetobacter baumannii: A comprehensive review of global epidemiology, clinical implications, host interactions, mechanisms of antimicrobial resistance and mitigation strategies","volume":"204","author":"Sharma","year":"2025","journal-title":"Microb. 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