{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T05:37:05Z","timestamp":1792042625828,"version":"4.4.0"},"reference-count":32,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,7,26]],"date-time":"2022-07-26T00:00:00Z","timestamp":1658793600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Sothema laboratory"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>The purpose of the present study is twofold. First, it aims to evaluate the synergistic action of the \u00df-lactam antibiotic; AMX is associated with 1,8-cineole on six clinical isolates of ESBL-producing Escherichia coli and Klebsiella pneumoniae strains. Second, it aims to determine the effect this association has on the ESBL enzymatic resistance mechanism. The synergistic action of AMX\/1,8-cineole was evaluated using partial inhibitory concentrations (PIC), determined by a microplate, a checkerboard and time\u2013kill assays. The effect of AMX\/1,8-cineole associations on the ESBL enzymatic resistance mechanism was evaluated using a new optimized enzymatic assay. This assay was based on the determination of the AMX antibacterial activity when combined with 1,8-cineole (at subinhibitory concentrations) in the presence or absence of the \u00df-lactamase enzyme toward a sensitive E. coli strain. The results of both checkerboard and time\u2013kill assays showed a strong synergistic action between AMX and 1,8-cineole. The results of the enzymatic assay showed that the combination of AMX with 1,8-cineole notably influences the enzymatic resistance of the reaction by decreasing the affinity of the \u03b2-lactam antibiotic, AMX, to the \u03b2-lactamase enzyme. All obtained results suggested that the AMX\/1,8-cineole association could be employed in therapy to overcome bacterial resistance to AMX while reducing the prevalence of resistance.<\/jats:p>","DOI":"10.3390\/antibiotics11081002","type":"journal-article","created":{"date-parts":[[2022,7,26]],"date-time":"2022-07-26T22:03:42Z","timestamp":1658873022000},"page":"1002","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Synergistic Action of AMX Associated with 1,8-Cineole and Its Effect on the ESBL Enzymatic Resistance Mechanism"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4133-2381","authenticated-orcid":false,"given":"Ahmed Amin","family":"Akhmouch","sequence":"first","affiliation":[{"name":"Department of Biology, Faculty of Science Dhar El Mahraz, University Sidi Mohammed Ben Abdellah, Atlas-Fez 1796, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7161-3088","authenticated-orcid":false,"given":"Soukayna","family":"Hriouech","sequence":"additional","affiliation":[{"name":"Department of Biology, Faculty of Science Dhar El Mahraz, University Sidi Mohammed Ben Abdellah, Atlas-Fez 1796, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6070-0293","authenticated-orcid":false,"given":"Aouatef","family":"Mzabi","sequence":"additional","affiliation":[{"name":"Department of Biology, Faculty of Science Dhar El Mahraz, University Sidi Mohammed Ben Abdellah, Atlas-Fez 1796, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3486-2517","authenticated-orcid":false,"given":"Mariam","family":"Tanghort","sequence":"additional","affiliation":[{"name":"Department of Biology, Faculty of Science Dhar El Mahraz, University Sidi Mohammed Ben Abdellah, Atlas-Fez 1796, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2216-6621","authenticated-orcid":false,"given":"Hanane","family":"Chefchaou","sequence":"additional","affiliation":[{"name":"Department of Biology, Faculty of Science Dhar El Mahraz, University Sidi Mohammed Ben Abdellah, Atlas-Fez 1796, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adnane","family":"Remmal","sequence":"additional","affiliation":[{"name":"Department of Biology, Faculty of Science Dhar El Mahraz, University Sidi Mohammed Ben Abdellah, Atlas-Fez 1796, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Najat","family":"Chami","sequence":"additional","affiliation":[{"name":"Department of Biology, Faculty of Science Dhar El Mahraz, University Sidi Mohammed Ben Abdellah, Atlas-Fez 1796, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e160","DOI":"10.1016\/S2666-5247(22)00006-4","article-title":"Metabolic perspective into antimicrobial tolerance and resistance","volume":"3","author":"Bhusal","year":"2022","journal-title":"Lancet Microbe"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"45","DOI":"10.2147\/IDR.S234353","article-title":"How Phages Overcome the Challenges of Drug Resistant Bacteria in Clinical Infections","volume":"13","author":"Taati","year":"2020","journal-title":"Infect. 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