ABSTRACT
The demand for carotenoids as food color, nutraceutical, and feed additive has been increasing. Animals are dependent on their diet for carotenoids, as they do not synthesize them. There is increasing scientific evidence to show the protective role of dietary carotenoids against many degenerative diseases owing to their antioxidant activity. The extreme environments induce carotenoid accumulation in microalgae, and therefore the extremophilic microalgae can be a potential resource pool for natural carotenoids. However, the potential of extremophilic microalgae has remained largely unexplored, with halophilic Dunaliella sp. being the only microalga commercialized for β-carotene production. This chapter provides an account of the current status of extremophilic microalgae and their potential as a source of carotenoids. The chapter discusses carotenoid biosynthesis, major algal carotenoids, and their role and applications. Some important extremophilic microalgae and their carotenoid distribution and cultivation strategies are also discussed.
