Selecting for a high lipid accumulating microalgae culture by dual growth limitation in a continuous bioreactor.

Autor: Policastro G; Department of Engineering and Computer Science, Telematic University Pegaso, Naples, Italy; Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Naples, Italy. Electronic address: grazia.policastro@unipegaso.it., Ebrahimi S; Biotechnology Research Center, Faculty of Chemical Engineering, Sahand University of Technology, Tabriz, Iran; Department of Biotechnology, Delft University of Technology, Delft, the Netherlands., Weissbrodt DG; Department of Biotechnology, Delft University of Technology, Delft, the Netherlands; Department of Biotechnology and Natural Sciences, Norwegian University of Science and Technology, Trondheim, Norway., Fabbricino M; Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Naples, Italy., van Loosdrecht MCM; Department of Biotechnology, Delft University of Technology, Delft, the Netherlands. Electronic address: m.c.m.vanloosdrecht@tudelft.nl.
Jazyk: angličtina
Zdroj: The Science of the total environment [Sci Total Environ] 2024 Feb 20; Vol. 912, pp. 169213. Date of Electronic Publication: 2023 Dec 12.
DOI: 10.1016/j.scitotenv.2023.169213
Abstrakt: 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.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE