Effects of irradiance, temperature, nutrients, and pCO2 on the growth and biochemical composition of cultivated Ulva fenestrata
Journal article, 2020

Ulva fenestrata is an economically and ecologically important green algal species with a large potential in seaweed aquaculture due to its high productivity, wide environmental tolerance, as well as interesting functional and nutritional properties. Here, we performed a series of manipulative cultivation experiments in order to investigate the effects of irradiance (50, 100, and 160 μmol photons m−2 s−1), temperature (13 and 18 °C), nitrate (< 5, 150, and 500 μM), phosphate (< 1 and 50 μM), and pCO2 (200, 400, and 2500 ppm) on the relative growth rate and biochemical composition (fatty acid, protein, phenolic, ash, and biochar content) in indoor tank cultivation of Swedish U. fenestrata. High irradiance and low temperature were optimal for the growth of this northern hemisphere U. fenestrata strain, but addition of nutrients or changes in pCO2 levels were not necessary to increase growth. Low irradiance resulted in the highest fatty acid, protein, and phenolic content, while low temperature had a negative effect on the fatty acid content but a positive effect on the protein content. Addition of nutrients (especially nitrate) increased the fatty acid, protein, and phenolic content. High nitrate levels decreased the total ash content of the seaweeds. The char content of the seaweeds did not change in response to any of the manipulated factors, and the only significant effect of changes in pCO2 was a negative relationship with phenolic content. We conclude that the optimal cultivation conditions for Swedish U. fenestrata are dependent on the desired biomass traits (biomass yield or biochemical composition).

Biochemical composition

Ulva lactuca

Ulva fenestrata

Chlorophyceae

Relative growth rate

Aquaculture

Macroalgae

Author

Gunilla B. Toth

University of Gothenburg

Hanna Harrysson

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Niklas Wahlström

Royal Institute of Technology (KTH)

Joakim Olsson

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

Annelous Oerbekke

University of Gothenburg

Sophie Steinhagen

University of Gothenburg

Alexandra Kinnby

University of Gothenburg

Joel White

University of Gothenburg

Eva Albers

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

Ulrica Edlund

Royal Institute of Technology (KTH)

Ingrid Undeland

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Henrik Pavia

University of Gothenburg

Journal of Applied Phycology

0921-8971 (ISSN) 1573-5176 (eISSN)

Vol. In Press

Subject Categories

Ecology

DOI

10.1007/s10811-020-02155-8

More information

Latest update

6/30/2020