Bioprocess engineering to revolutionize polyunsaturated fatty acid production by suppressing undesirable fatty acids flux

Abstract BACKGROUND Microbial bioprocesses provide a sustainable alternative for producing high‐value biomolecules such as omega‐3 and omega‐6 polyunsaturated fatty acids (PUFAs). Aurantiochytrium sp., a marine oleaginous microorganism, holds great potential for biomass valorization through optimized lipid biosynthesis. The present study explores a novel strategy combining chemical inhibitors [quizalofop‐ p ‐ethyl (QPE) and triclosan] with abiotic cold stress to reprogram metabolic pathways, enhancing omega‐PUFA accumulation at the same time as reducing saturated and monounsaturated fatty acid synthesis. RESULTS The integration of cold stress and triclosan increased lipid productivity by 15.28% (7.02 g L −1 ), significantly enhancing docosahexaenoic acid (DHA) (29.52%, 2.72 g L −1 ), DPA (45%, 0.31 g L −1 ) and eicosapentaenoic acid (EPA) (200%, 0.12 g L −1 ). Similarly, QPE combined with cold stress boosted lipid yield by 22.66% (7.47 g L −1 ), with notable increases in DPA (85%), DHA (21.9%) and arachidonic acid (ARA) (15.38%, 0.15 g L −1 ). The synergistic effect of triclosan and QPE further amplified EPA and ARA production by 250% and 30.8%, respectively. CONCLUSION This study demonstrates a cost‐effective, scalable bioprocess for sustainable omega‐3 and omega‐6 PUFA production, reducing reliance on fish oil and supporting marine conservation. Additionally, this approach aligns with the United Nations' Sustainable Development Goals (SDGs 7 and 13), promoting bioresource utilization for renewable energy and bioproduct applications. © 2025 Society of Chemical Industry.