{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T01:49:25Z","timestamp":1774576165837,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2018,9,11]],"date-time":"2018-09-11T00:00:00Z","timestamp":1536624000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["ZEBRALGRE (PTDC\/CVT-WEL\/5207\/2014)"],"award-info":[{"award-number":["ZEBRALGRE (PTDC\/CVT-WEL\/5207\/2014)"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["NORTE-01-0145-FEDER-000035"],"award-info":[{"award-number":["NORTE-01-0145-FEDER-000035"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["DINOSSAUR\u2014PTDC\/BBB-EBB\/1374\/2014-POCI-01-0145-FEDER-016640"],"award-info":[{"award-number":["DINOSSAUR\u2014PTDC\/BBB-EBB\/1374\/2014-POCI-01-0145-FEDER-016640"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Marine Drugs"],"abstract":"<jats:p>The nutraceutical potential of microalgae boomed with the exploitation of new species and sustainable extraction systems of bioactive compounds. Thus, a laboratory-made continuous pressurized solvent extraction system (CPSE) was built to optimize the extraction of antioxidant compounds, such as carotenoids and PUFA, from a scarcely studied prokaryotic microalga, Gloeothece sp. Following \u201cgreen chemical principles\u201d and using a GRAS solvent (ethanol), biomass amount, solvent flow-rate\/pressure, temperature and solvent volume\u2014including solvent recirculation\u2014were sequentially optimized, with the carotenoids and PUFA content and antioxidant capacity being the objective functions. Gloeothece sp. bioactive compounds were best extracted at 60 \u00b0C and 180 bar. Recirculation of solvent in several cycles (C) led to an 11-fold extraction increase of \u03b2-carotene (3C) and 7.4-fold extraction of C18:2 n6 t (5C) when compared to operation in open systems. To fully validate results CPSE, this system was compared to a conventional extraction method, ultrasound assisted extraction (UAE). CPSE proved superior in extraction yield, increasing total carotenoids extraction up 3-fold and total PUFA extraction by ca. 1.5-fold, with particular extraction increase of 18:3 n3 by 9.6-fold. Thus, CPSE proved to be an efficient and greener extraction method to obtain bioactive extract from Gloeothece sp. for nutraceutical purposes\u2014with low levels of resources spent, while lowering costs of production and environmental impacts.<\/jats:p>","DOI":"10.3390\/md16090327","type":"journal-article","created":{"date-parts":[[2018,9,11]],"date-time":"2018-09-11T11:40:02Z","timestamp":1536666002000},"page":"327","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Gloeothece sp. as a Nutraceutical Source\u2014An Improved Method of Extraction of Carotenoids and Fatty Acids"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2832-0543","authenticated-orcid":false,"given":"Helena M.","family":"Amaro","sequence":"first","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General Norton de Matos, S\/N, P-4450-208 Matosinhos, Portugal"},{"name":"Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Rua Jorge Viterbo Ferreira no. 228, P-4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9181-512X","authenticated-orcid":false,"given":"A. Catarina","family":"Guedes","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General Norton de Matos, S\/N, P-4450-208 Matosinhos, Portugal"}]},{"given":"Marco A. C.","family":"Preto","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General Norton de Matos, S\/N, P-4450-208 Matosinhos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9231-0553","authenticated-orcid":false,"given":"I.","family":"Sousa-Pinto","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leix\u00f5es, Avenida General Norton de Matos, S\/N, P-4450-208 Matosinhos, Portugal"},{"name":"FCUP\u2014Faculty of Sciences, University of Porto, Rua do Campo Alegre s\/n, 4169-007 Porto, Portugal"}]},{"given":"F. Xavier","family":"Malcata","sequence":"additional","affiliation":[{"name":"LEPABE\u2014Laboratory of Process Engineering, Environment, Biotechnology and Energy, Rua Dr. Roberto Frias s\/n, P-4200-465 Porto, Portugal"},{"name":"Department of Chemical Engineering, University of Porto, Rua Dr. Roberto Frias, s\/n 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,9,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"743","DOI":"10.1007\/s10811-013-9983-9","article-title":"High-value products from microalgae\u2014Their development and commercialisation","volume":"25","author":"Borowitzka","year":"2013","journal-title":"J. Appl. Phycol."},{"key":"ref_2","unstructured":"Ahsan, M., Habib, B., and Parvin, M. (2008). 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