Can We Approach Theoretical Lipid Yields in Microalgae?

Can we approach theoretical lipid yields in microalgae? Yes: we can substantially reduce the gap between current and theoretical maximum yield. A realistic maximum is approximately 0.5. g triacylglycerol (TAG) per mol photons, about five times higher than what is currently achieved in outdoor cultivation. Achieving this realistic maximum will require several breakthroughs. First, outdoor operation typically has low yields, mainly caused by fluctuating insolation. Future adaptive control models will help increase these yields. Additionally, the lipid production capacity of currently used strains needs to increase. Powerful strain-specific molecular toolboxes are being developed, shifting the bottleneck towards understanding metabolism and identifying target genes. Finally, strains and processes should be improved concurrently to fully exploit the potential lipid production from microalgae. To fulfill the necessity for improved yields in microalgal lipid production, current research is moving towards advanced cultivation strategies, including adaptation to fluctuating outdoor weather conditions.Recent developments of targeted gene-editing technology (e.g., CRISPR/Cas9) and improved high-throughput screening techniques in microalgae contribute to fast and automatized strain improvement approaches.Industrial needs and higher oil productivities of microalgae compared with plants will foster the development of tailored microalgal oils.