Innovative strategies for augmenting Omega-3-Fatty acid production in microalgae: Sustainable approaches for vegan food applications

Abstract

The virtues of omega-3-polyunsaturated fatty acids (ω-3-PUFAs) have garnered considerable acclaim owing to their multifaceted human health benefits. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) represent long-chain ω-3-PUFAs synthesized from the precursor α-linoleic acid (ALA). Conventionally, fish, shellfish, and krill have been the primary sources of omega-3 fatty acids. However, with declining marine stocks and increasing demand from vegan populations, there is a growing need for alternative, sustainable sources. This review aims to critically evaluate and consolidate recent advances in microalgal biotechnology for enhancing the production of ω-3-PUFAs from microalgae. This comprehensive review work covers diverse techniques from abiotic stress and nutrient manipulations to enhance lipids as well as ω-3-PUFA contents to sophisticated metabolic engineering approaches aimed at augmenting ALA, EPA, and DHA levels in microalgae. The article emphasizes the use of genetic engineering techniques, focusing on innovative gene editing tools such as RNA interface (RNAi), clustered regularly interspaced short palindromic repeats (CRISPR-Cas9), and transcription activator-like effector nucleases (TALEN) for the manipulation of key lipid/ fatty acid biosynthesis enzymes. Emphasis is placed on the scalable cultivation systems (e.g., photobioreactors, raceway ponds) and eco-friendly downstream processes like green solvent extraction and molecular distillation. Overall, this review highlights the growing potential of microalgal biotechnology to sustainably meet the rising global demand for ω-3-PUFAs and provides insights for future research toward large-scale, eco-friendly ω-3-PUFA production.

Keywords: Docosahexaenoic acid (DHA); Eicosapentaenoic acid (EPA); Lipids; Microalgae; Vegan; ω-3-PUFA.