Print Email Facebook Twitter Selecting for a high lipid accumulating microalgae culture by dual growth limitation in a continuous bioreactor Title Selecting for a high lipid accumulating microalgae culture by dual growth limitation in a continuous bioreactor Author Policastro, G. (TU Delft BT/Environmental Biotechnology; Università degli Studi di Napoli Federico II) Ebrahimi, S. (TU Delft BT/Environmental Biotechnology; Sahand University of Technology) Weissbrodt, D.G. (TU Delft BT/Environmental Biotechnology; Norwegian University of Science and Technology (NTNU)) Fabbricino, Massimiliano (Università degli Studi di Napoli Federico II) van Loosdrecht, Mark C.M. (TU Delft BT/Environmental Biotechnology) Date 2024 Abstract A dual-growth-limited continuous operated bioreactor (chemostat) was used to enhance lipid accumulation in an enrichment culture of microalgae. The light intensity and nitrogen concentration where both limiting factors resulting in high lipid accumulation in the mixed culture. Both conditions of light and nitrogen excess and deficiency were tested. Strategies to selectively enrich for a phototrophic lipid-storing community, based on the use of different nitrogen sources (ammonium vs. nitrate) and vitamin B supplementation in the growth medium, were evaluated. The dual limitation of both nitrogen and light enhanced the accumulation of storage compounds. Ammoniacal nitrogen was the preferred nitrogen source. Vitamin B supplementation led to a doubling of the lipid productivity. The availability of vitamins played a key role in selecting an efficient lipid-storing community, primarily consisting of Trebouxiophyceae (with an 82 % relative abundance among eukaryotic microorganisms). The obtained lipid volumetric productivity (387 mg L−1 d−1) was among the highest reported in literature for microalgae bioreactors. Lipid production by the microalgae enrichment surpassed the efficiencies reported for continuous microalgae pure cultures, highlighting the benefits of mixed-culture photo-biotechnologies for fuels and food ingredients in the circular economy. Subject AmmoniumDual growth limitationLipid productionMixed culture microalgaeVitamin B To reference this document use: http://resolver.tudelft.nl/uuid:6231852e-42cc-469b-9e77-f9134726cf38 DOI https://doi.org/10.1016/j.scitotenv.2023.169213 Embargo date 2024-06-12 ISSN 0048-9697 Source Science of the Total Environment, 912 Bibliographical note Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2024 G. Policastro, S. Ebrahimi, D.G. Weissbrodt, Massimiliano Fabbricino, Mark C.M. van Loosdrecht Files PDF 1_s2.0_S0048969723078439_main.pdf 2.63 MB Close viewer /islandora/object/uuid:6231852e-42cc-469b-9e77-f9134726cf38/datastream/OBJ/view