Microalgae have long been celebrated as a sustainable source of biomass for producing a range of bioproducts, from biofuels to pharmaceuticals. However, optimizing their efficiency at large-scale cultivation remains a significant challenge. A new open-access review published in Frontiers in Photobiology by GAIN4CROPS partners, Giorgio Perin and Tomas Morosinotto, from the University of Padova delves into the complexities of improving photosynthetic light-reactions in microalgae photobioreactors, offering insights to boost biomass productivity and photosynthesis efficiency in higher plants.
Microalgae are usually grown in photobioreactors (PBRs), where light availability often limits productivity. Natural light fluctuates with the seasons, time of day, and weather, while artificial lighting in PBRs can create additional challenges. The review highlights how despite microalgae’s evolved mechanisms to manage dynamic light conditions, these are not always effective in the artificial environments of large-scale cultivation.
Strategies for Enhancing Photosynthetic Efficiency
The authors list several promising approaches to optimize the efficiency of microalgae in industrial environments. In large-scale cultivation, it’s important to optimize light-use efficiency and photoprotection. For example, metabolic engineering can modify light-harvesting complexes to improve overall efficiency.
Adjusting the regulatory mechanisms of photosynthesis was another proposed way to improve performance under fluctuating light conditions. Alternatively, optimizing electron transport reactions through synthetic biology approaches could mitigate light-induced damage and improve growth.
One of the key insights from the review is the gap between lab-scale and industrial-scale performance.
Many genetic modifications that show promise in the lab do not always translate effectively to larger scales due to the increased complexity of the cultivation environment. So it is important to develop more sophisticated models to predict how these genetic modifications will perform in real-world settings.
Implications for GAIN4CROPS
The insights from this review are particularly relevant for the GAIN4CROPS project, which aims to enhance crop productivity by improving photosynthetic efficiency. While GAIN4CROPS final target is the sunflower, its step-wise approach hinges on engineering synthetic metabolic pathways on algae and moss. So, understanding how to optimize photosynthesis in microalgae can provide valuable parallels and inspire similar approaches in crop plants to enhance overall photosynthetic performance and boost productivity.
