{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T13:21:30Z","timestamp":1790256090280,"version":"4.1.0"},"reference-count":42,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T00:00:00Z","timestamp":1773187200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"UOS-UAEU","award":["25010901175"],"award-info":[{"award-number":["25010901175"]}]},{"name":"Eugen Ionescu","award":["2021\/2022"],"award-info":[{"award-number":["2021\/2022"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>Background\/Objectives:\u00a0Citrus limon leaf essential oil (EO) is traditionally used for its calming and cognitive-enhancing properties. Although the chemical composition of C. limon leaf essential oils (EOs) obtained by means of hydrodistillation (HD) and solvent-free microwave extraction (SFME) has been previously characterized, the influence of the extraction method on their neuroprotective efficacy and dose\u2013response effects remains insufficiently explored. In the present study, EOs obtained by means of HD (CEH) and SFME (CEM) were compared for their behavioral, biochemical, and in silico neuroprotective effects against scopolamine (SCOP)-induced cognitive and anxiety-like impairments in adult zebrafish. Methods: Adult T\u00fcbingen zebrafish were exposed to CEH or CEM via immersion at 10, 100, and 150 \u00b5L\/L for 19 days prior to SCOP challenge (100 \u00b5M). Cognitive performance was evaluated using the Y-maze and novel object recognition (NOR) tests, while anxiety-like behavior was assessed using the novel tank test (NTT) and novel approach test (NAT). Brain acetylcholinesterase (AChE) activity and oxidative stress markers were quantified. Molecular docking analyses were conducted to investigate interactions between major EO constituents and AChE and monoamine oxidase A (MAO A). Results: Both CEH and CEM significantly attenuated SCOP-induced memory deficits, improved spontaneous alternation and NOR discrimination, and reduced anxiety-like behaviors. These effects were associated with AChE inhibition and restoration of redox balance. Notably, CEM generally exhibited stronger neurobehavioral and biochemical effects at comparable doses. In silico analyses supported these findings, revealing favorable binding affinities of key EO constituents toward cholinergic and monoaminergic targets. Conclusions: This study demonstrates that the extraction method influences the neuroprotective efficacy of C. limon leaf EOs. While both CEH and CEM exert antioxidant and cholinergic modulatory effects, CEM shows enhanced neuroprotective potential in a zebrafish model of SCOP-induced cognitive impairment, supporting the relevance of extraction-dependent biological profiling in EO-based neurotherapeutic research.<\/jats:p>","DOI":"10.3390\/ph19030458","type":"journal-article","created":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T11:44:52Z","timestamp":1773229492000},"page":"458","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Behavioral, Biochemical, and In Silico Evidence for Extraction-Dependent Neuroprotective Effects of Citrus limon Leaf Essential Oils in Scopolamine-Challenged Zebrafish"],"prefix":"10.3390","volume":"19","author":[{"given":"Salwa","family":"Bouabdallah","sequence":"first","affiliation":[{"name":"Laboratory of Environmental Biosurveillance (LR01\/ES14), Faculty of Sciences of Bizerte, University of Carthage, Zarzouna 7021, Tunisia"},{"name":"Department of Biology, Faculty of Biology, Alexandru Ioan Cuza University of Iasi, 700506 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1305-7965","authenticated-orcid":false,"given":"Ahmed","family":"Kouki","sequence":"additional","affiliation":[{"name":"Laboratory of Environmental Biosurveillance (LR01\/ES14), Faculty of Sciences of Bizerte, University of Carthage, Zarzouna 7021, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8235-5715","authenticated-orcid":false,"given":"Mona H.","family":"Ibrahim","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Medicinal Chemistry and Drug Design, Faculty of Pharmacy (Girls), Al-Azhar University, Cairo 11754, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3103-9728","authenticated-orcid":false,"given":"Ion","family":"Brinza","sequence":"additional","affiliation":[{"name":"Faculty of Sciences, \u201cLucian Blaga\u201d University of Sibiu, 7\u20139 Ion Ratiu Street, 550024 Sibiu, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2602-4882","authenticated-orcid":false,"given":"Razvan Stefan","family":"Boiangiu","sequence":"additional","affiliation":[{"name":"Department of Biology, Faculty of Biology, Alexandru Ioan Cuza University of Iasi, 700506 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5368-4800","authenticated-orcid":false,"given":"Mossadok","family":"Ben-Attia","sequence":"additional","affiliation":[{"name":"Laboratory of Environmental Biosurveillance (LR01\/ES14), Faculty of Sciences of Bizerte, University of Carthage, Zarzouna 7021, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6981-4174","authenticated-orcid":false,"given":"Lucian","family":"Hritcu","sequence":"additional","affiliation":[{"name":"Department of Biology, Faculty of Biology, Alexandru Ioan Cuza University of Iasi, 700506 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8888-1102","authenticated-orcid":false,"given":"Amr","family":"Amin","sequence":"additional","affiliation":[{"name":"College of Medicine, University of Sharjah, Sharjah P.O. Box 27272, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,11]]},"reference":[{"key":"ref_1","unstructured":"Prince, M., Wimo, A., Guerchet, M., Ali, G.-C., Wu, Y.-T., and Prina, M. (2015). World Alzheimer Report 2015: The Global Impact of Dementia, Alzheimer\u2019s Disease International."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1038\/s41583-019-0132-6","article-title":"Oxidative stress, dysfunctional glucose metabolism and Alzheimer disease","volume":"20","author":"Butterfield","year":"2019","journal-title":"Nat. Rev. Neurosci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"814068","DOI":"10.1155\/2015\/814068","article-title":"Phytochemicals that regulate neurodegenerative disease by targeting neurotrophins: A review","volume":"2015","author":"Venkatesan","year":"2015","journal-title":"Biomed. Res. 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