Synthetic biology in microalgae towards fucoxanthin production for pharmacy and nutraceuticals.

Synthetic biology has emerged as a powerful tool for engineering biological systems to produce valuable compounds, including pharmaceuticals and nutraceuticals. Microalgae, in particular, offer a promising platform for the production of bioactive compounds due to their high productivity, low land and water requirements, and ability to perform photosynthesis. Fucoxanthin, a carotenoid pigment found predominantly in brown seaweeds and certain microalgae, has gained significant attention in recent years due to its numerous health benefits, such as antioxidation, antitumor effect and precaution osteoporosis. This review provides an overview of the principles and applications of synthetic biology in the microbial engineering of microalgae for enhanced fucoxanthin production. Firstly, the fucoxanthin bioavailability and metabolism in vivo was introduced for the beneficial roles, followed by the biological functions of anti-oxidant activity, anti-inflammatory activity, antiapoptotic role antidiabetic and antilipemic effects. Secondly, the cultivation condition and strategy were summarized for fucoxanthin improvement with low production costs. Thirdly, the genetic engineering of microalgae, including gene overexpression, knockdown and knockout strategies were discussed for further improving the fucoxanthin production. Then, synthetic biology tools of CRISPR-Cas9 genome editing, transcription activator-like effector nucleases as well as modular assembly and chassis engineering were proposed to precise modification of microalgal genomes to improve fucoxanthin production. Finally, challenges and future perspectives were discussed to realize the industrial production and development of functional foods of fucoxanthin from microalgae.