A perspective of microalga-derived omega-3 fatty acids: scale up and engineering challenges

Omega-3 fatty acids (n-3 FAs), including alpha-linolenic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), are essential for human health, significantly contributing to cardiovascular health, neurocognitive function, and immune modulation. Traditionally, these fatty acids are sourced from flaxseeds, walnuts, and fatty fish like salmon and mackerel. Recently, microalgae have gained attention as a sustainable source of n-3 FAs, as they are primary producers of EPA and DHA in aquatic ecosystems. This review examines Omega-3 fatty acid production and extraction methods, evaluating their efficiency and oxidative stability. It explores both chemical and natural synthesis of n-3 FAs and reviews advanced analytical techniques for accurate identification and quantification. The review addresses current research on improved extraction efficiency from microalgae, highlighting the limitations of microreactors and laboratory-scale optimizations. It also examines the growth parameters necessary for successful scale-up of microalgae cultivation, focusing on light intensity, mixing, mass transfer, temperature, and pH. However, current research is primarily limited to laboratory-scale studies, necessitating further exploration into large-scale applications. Optimizing growth parameters such as agitation, pH, temperature and enhanced mass transfer is crucial for successful scale-up. The case study of raceway open pond systems illustrates the potential for commercial-scale cultivation, emphasizing the need for continued research to achieve sustainable, large-scale production of microalgae-derived n-3 FAs.