High-EPA Biomass from Nannochloropsis salina Cultivated in a Flat-Panel Photo-Bioreactor on a Process Water-Enriched Growth Medium

Mar Drugs. 2016 Jul 29;14(8):144. doi: 10.3390/md14080144.


Nannochloropsis salina was grown on a mixture of standard growth media and pre-gasified industrial process water representing effluent from a local biogas plant. The study aimed to investigate the effects of enriched growth media and cultivation time on nutritional composition of Nannochloropsis salina biomass, with a focus on eicosapentaenoic acid (EPA). Variations in fatty acid composition, lipids, protein, amino acids, tocopherols and pigments were studied and results compared to algae cultivated on F/2 media as reference. Mixed growth media and process water enhanced the nutritional quality of Nannochloropsis salina in laboratory scale when compared to algae cultivated in standard F/2 medium. Data from laboratory scale translated to the large scale using a 4000 L flat panel photo-bioreactor system. The algae growth rate in winter conditions in Denmark was slow, but results revealed that large-scale cultivation of Nannochloropsis salina at these conditions could improve the nutritional properties such as EPA, tocopherol, protein and carotenoids compared to laboratory-scale cultivated microalgae. EPA reached 44.2% ± 2.30% of total fatty acids, and α-tocopherol reached 431 ± 28 µg/g of biomass dry weight after 21 days of cultivation. Variations in chemical compositions of Nannochloropsis salina were studied during the course of cultivation. Nannochloropsis salina can be presented as a good candidate for winter time cultivation in Denmark. The resulting biomass is a rich source of EPA and also a good source of protein (amino acids), tocopherols and carotenoids for potential use in aquaculture feed industry.

Keywords: EPA; Nannochloropsis salina; amino acid; carotenoids; flat panel photo-bioreactor; industrial process water; large scale; microalgae; tocopherol.

MeSH terms

  • Animal Feed
  • Aquaculture / instrumentation*
  • Batch Cell Culture Techniques*
  • Biofuels
  • Bioreactors / economics*
  • Culture Media / chemistry
  • Eicosapentaenoic Acid / metabolism*
  • Light
  • Microalgae / chemistry*
  • Stramenopiles / chemistry
  • Stramenopiles / growth & development*
  • Temperature
  • Time Factors
  • Water / chemistry
  • alpha-Tocopherol / metabolism*


  • Biofuels
  • Culture Media
  • Water
  • Eicosapentaenoic Acid
  • alpha-Tocopherol