{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T02:54:57Z","timestamp":1783392897552,"version":"3.54.6"},"reference-count":46,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,9,20]],"date-time":"2022-09-20T00:00:00Z","timestamp":1663632000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"American University of Sharjah"},{"name":"University of Sharjah"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Naegleria fowleri and Balamuthia mandrillaris are opportunistic protists, responsible for fatal central nervous system infections such as primary amoebic meningoencephalitis (PAM) and granulomatous amoebic encephalitis (GAE) with mortality rates higher than 90%. Threatening a rise in cases is the increase in temperature due to global warming. No effective treatment is currently available. Herein, nanotechnology was used to conjugate Zinc oxide with Ampicillin, Ceftrixon, Naringin, Amphotericin B, and Quericitin, and the amoebicidal activity and host cell cytotoxicity of these resulting compounds were investigated. The compounds ZnO-CD-AMPi, ZnO-CD-CFT, ZnO-CD-Nar, ZnO-CD-AMB, and ZnO-CD-QT were found to reduce N. fowleri viability to 35.5%, 39.6%, 52.0%, 50.8%, 35.9%, and 69.9%, respectively, and B. mandrillaris viability to 40.9%, 48.2%, 51.6%, 43.8%, and 62.4%, respectively, when compared with their corresponding controls. Furthermore, the compounds reduced N. fowleri-mediated and B. mandrillaris-mediated host cell death significantly. Additionally, the compounds showed limited cytotoxicity against human cells; cell toxicity was 35.5%, 36.4%, 30.9%, 36.6%, and 35.6%, respectively, for the compounds ZnO-CD-AMPi, ZnO-CD-CFT, ZnO-CD-Nar, ZnO-CD-AMB, and ZnO-CD-QT. Furthermore, the minimum inhibitory concentrations to inhibit amoeba growth by 50% were determined for N. fowleri and B. mandrillaris. The MIC50 for N. fowleri were determined to be 69.52 \u00b5g\/mL, 82.05 \u00b5g\/mL, 88.16 \u00b5g\/mL, 95.61 \u00b5g\/mL, and 85.69 \u00b5g\/mL, respectively; the MIC50 of the compounds for B. mandrillaris were determined to be 113.9 \u00b5g\/mL, 102.3 \u00b5g\/mL, 106.9 \u00b5g\/mL, 146.4 \u00b5g\/mL, and 129.6 \u00b5g\/mL, respectively. Translational research to further develop therapies based on these compounds is urgently warranted, given the lack of effective therapies currently available against these devastating infections.<\/jats:p>","DOI":"10.3390\/antibiotics11101281","type":"journal-article","created":{"date-parts":[[2022,9,20]],"date-time":"2022-09-20T21:12:53Z","timestamp":1663708373000},"page":"1281","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Zinc Oxide Nanoconjugates against Brain-Eating Amoebae"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9646-6208","authenticated-orcid":false,"given":"Ruqaiyyah","family":"Siddiqui","sequence":"first","affiliation":[{"name":"College of Arts and Sciences, American University of Sharjah, University City, Sharjah 26666, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anania","family":"Boghossian","sequence":"additional","affiliation":[{"name":"College of Arts and Sciences, American University of Sharjah, University City, Sharjah 26666, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Noor","family":"Akbar","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tooba","family":"Jabri","sequence":"additional","affiliation":[{"name":"H.E.J. Research Institute of Chemistry, International Centre for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zara","family":"Aslam","sequence":"additional","affiliation":[{"name":"H.E.J. Research Institute of Chemistry, International Centre for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muhammad Raza","family":"Shah","sequence":"additional","affiliation":[{"name":"H.E.J. Research Institute of Chemistry, International Centre for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmad M.","family":"Alharbi","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, Taif 21944, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0017-4337","authenticated-orcid":false,"given":"Hasan","family":"Alfahemi","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, Faculty of Medicine, Al-Baha University, Al-Baha 65799, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7667-8553","authenticated-orcid":false,"given":"Naveed Ahmed","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"791","DOI":"10.1111\/cts.12955","article-title":"Drugs used for the treatment of cerebral and disseminated infections caused by free-living amoebae","volume":"14","author":"Taravaud","year":"2021","journal-title":"Clin. 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