In vitro fucoxanthin production by the Phaeodactylum tricornutum diatom

Abstract Diatoms, along with brown seaweeds, are the main producers of fucoxanthin, an oxycarotenoid with important biological functions such as antioxidant, anti-obesity, antitumor, antidiabetic, and anti-inflammatory activities. In this scenario, the marine diatom Phaeodactylum tricornutum is considered an important source of this carotenoid. Fucoxanthin production by this diatom has been studied through different approaches, e.g., in vitro and in vivo investigation of the effects of environmental factors and strains, as well as through metabolic engineering analysis. The optimization of environmental factors such as light exposure, pH, temperature and aeration has been reported to modulate fucoxanthin production by P. tricornutum cell cultures. In parallel, the identification and selection of strains with an elevated fucoxanthin biosynthesis and accumulation have also contributed to improve the biotechnological performance of that microalga. Indeed, much can be done from the screening of the genomic sequence of P. tricornutum, which has been completed in 2008. Candidate genes for specific reactions in carotenoid biosynthesis pathways can be cloned, expressed, and identified by combining genetic and analytical strategies. Furthermore, metabolic reactions can be used to perform in vitro simulations, mitigating laboratory costs. This chapter aims to present an overview of fucoxanthin biosynthesis in P. tricornutum as well as the different ways to enhance its production.