{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T16:16:49Z","timestamp":1786378609637,"version":"build-2736575974"},"reference-count":36,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,6,10]],"date-time":"2021-06-10T00:00:00Z","timestamp":1623283200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100007637","name":"Colciencias","doi-asserted-by":"publisher","award":["275908943."],"award-info":[{"award-number":["275908943."]}],"id":[{"id":"10.13039\/100007637","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Microalgae provides an alternative for the valorization of industrial by-products, in which the nutritional content varies substantially and directly affects microalgae system performance. Herein, the heterotrophic cultivation of Chlorella sorokiniana was systematically studied, allowing us to detect a nutritional deficiency other than the carbon source through assessing the oxygen transfer rate for glucose or acetate fermentation. Consequently, a mathematical model of the iron co-limiting effect on heterotrophic microalgae was developed by exploring its ability to regulate the specific growth rate and yield. For instance, higher values of the specific growth rate (0.17 h\u22121) compared with those reported for the heterotrophic culture of Chlorella were obtained due to iron supplementation. Therefore, anaerobic sludge from an industrial wastewater treatment plant (a baker\u2019s yeast company) was pretreated to obtain an extract as a media supplement for C. sorokiniana. According to the proposed model, the sludge extract allowed us to supplement iron values close to the growth activation concentration (KFe ~12 mg L\u22121). Therefore, a fed-batch strategy was evaluated on nitrogen-deprived cultures supplemented with the sludge extract to promote biomass formation and fatty acid synthesis. Our findings reveal that nitrogen and iron in sludge extract can supplement heterotrophic cultures of Chlorella and provide an alternative for the valorization of industrial anaerobic sludge.<\/jats:p>","DOI":"10.3390\/bioengineering8060082","type":"journal-article","created":{"date-parts":[[2021,6,9]],"date-time":"2021-06-09T22:18:29Z","timestamp":1623277109000},"page":"82","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Strategy for Managing Industrial Anaerobic Sludge through the Heterotrophic Cultivation of Chlorella sorokiniana: Effect of Iron Addition on Biomass and Lipid Production"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3823-1416","authenticated-orcid":false,"given":"Esteban","family":"Charria-Gir\u00f3n","sequence":"first","affiliation":[{"name":"Departamento de Ingenier\u00eda Bioqu\u00edmica, Facultad de Ingenier\u00eda, Universidad Icesi, Calle 18 No. 122\u2013135, Cali 760031, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vanessa","family":"Amazo","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Bioqu\u00edmica, Facultad de Ingenier\u00eda, Universidad Icesi, Calle 18 No. 122\u2013135, Cali 760031, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9238-8396","authenticated-orcid":false,"given":"Daniela","family":"De Angulo","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Bioqu\u00edmica, Facultad de Ingenier\u00eda, Universidad Icesi, Calle 18 No. 122\u2013135, Cali 760031, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eliana","family":"Hidalgo","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Bioqu\u00edmica, Facultad de Ingenier\u00eda, Universidad Icesi, Calle 18 No. 122\u2013135, Cali 760031, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7067-4113","authenticated-orcid":false,"given":"Mar\u00eda Francisca","family":"Villegas-Torres","sequence":"additional","affiliation":[{"name":"Departamento de Ciencias Qu\u00edmicas, Facultad de Ciencias Naturales, Universidad Icesi, Calle 18 No. 122\u2013135, Cali 760031, Colombia"},{"name":"Centro BioInc, Universidad Icesi, Calle 18 No. 122\u2013135, Cali 760031, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frank","family":"Baganz","sequence":"additional","affiliation":[{"name":"Department of Biochemical Engineering, University College London, Gordon Street, London WC1H 0AH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2133-7994","authenticated-orcid":false,"given":"Nelson. H.","family":"Caicedo Ortega","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Bioqu\u00edmica, Facultad de Ingenier\u00eda, Universidad Icesi, Calle 18 No. 122\u2013135, Cali 760031, Colombia"},{"name":"Centro BioInc, Universidad Icesi, Calle 18 No. 122\u2013135, Cali 760031, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1016\/j.ecoleng.2016.11.013","article-title":"Heterotrophic cultivation of microalgae using aquaculture wastewater: A biorefinery concept for biomass production and nutrient remediation","volume":"99","author":"Guldhe","year":"2017","journal-title":"Ecol. 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