Towards a sustainable supply of omega-3 fatty acids: Screening microalgae for scalable production of eicosapentaenoic acid (EPA)

Abstract

© 2021 The Authors. There is an increasing need for sustainable sources of omega-3 fatty acids; this challenge can be addressed through large-scale production of eicosapentaenoic acid (EPA) using microalgae. Identification of suitable strains is key in successful process scale-up. However, it is not certain whether conclusions from small-scale systems (i.e. flasks and well plates) can be translated to larger photobioreactors. To examine this issue the productivity and fatty acid composition of eleven different microalgal strains was quantified using both flask and photobioreactor cultures, generating a significant experimental dataset. Results from the flask screening offered relatively poor predictions of performance in photobioreactors, suggesting a need for improved screening tools. Of the species examined, Phaeodactylum tricornutum was found to be the most promising when grown in photobioreactors. To further guide scale-up the effect of environmental conditions (temperature and salinity) on EPA production was examined. It was found that the EPA content was ~5% of the dry biomass and this was approximately constant for the range of temperatures (13–27 °C) and salinities (35–50 g L−1) examined. Finally, detailed nutritional information about the biomass is presented, which can serve as a starting point for its formulation into food products.