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Production of metabolites in microalgae under alkali halophilic growth medium using a dissolved inorganic carbon source

journal contribution
posted on 2023-01-24, 10:23 authored by Uttam Roy, Jonathan WagnerJonathan Wagner, Tanja RaduTanja Radu

The production of metabolites in microalgae is influenced by extreme cultivation conditions. Bicarbonate is an inorganic carbon source for phototrophic microalgae culturing. In this study, the effect of dissolved inorganic carbon (DIC) (0.4 – 13 g L-1) on the accumulation of metabolites in Dunaliella tertiolecta biomass is presented. The highest levels of primary metabolites (lipid (239.6 ± 24.3 mg g-1), protein (336.2 ± 47.5 mg g-1)), secondary metabolites (total phenolic (12.8 ± 2.0 mg g-1), total flavonoid (14.4 ± 2.3 mg g-1), total ascorbate (4.7 ± 1.1 mg g-1)), and pigments (chlorophyll (27.2 ± 3.1 mg g-1), carotenoid (2.0 ± 0.1 mg g-1)) were observed when cells were grown with 5.7 g L-1 of DIC (NaHCO3). The highest biomass concentrations (1.5 ± 0.1 g L-1) were obtained for cells grown in a mixture of DIC (4.3 + 1.1 g L-1, NaHCO3 + Na2CO3). This study recommends the optimal levels of bicarbonate carbon of 5.7 g L-1 for maximising the generation of metabolites in the biomass. It also demonstrates that exogenous excessive DIC in the growth medium would be an effective stressor to produce high-value metabolites in Dunaliella or alkali-halophilic strains.

Statement of Novelty

Overall production of metabolites in D. tertiolecta CCAP 19/30 under high levels of NaHCO3 (alkalihalophilic medium) has not yet been reported. This study examines the effect of excess dissolved inorganic carbon on the growth of D. tertiolecta in order to maximize biomass yield and yields of the following metabolites: a) primary metabolites (lipid and protein); b) secondary metabolites (total phenolic content, ascorbate, and flavonoid); and c) pigment (chlorophyll and carotenoid). Based on the range of input conditions, the recommended optimal conditions for maximum yield of biomass and metabolites have been provided.


Integrated production of biomethane fuel with carbon sequestration: combining biological and thermochemical biomass treatment. (EPSRC) : SGBH FF Feb 2019 2



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Published in

Waste and Biomass Valorization




AM (Accepted Manuscript)

Publisher statement

This version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Nature’s AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at:

Acceptance date









Dr Tanja Radu. Deposit date: 23 January 2023