Microalgae as an Alternative Sustainable Source of Squalene
Squalene is a high value, C30-terpenoid and forms an intermediary metabolite of sterol synthesis in plants. It finds broad applications in the pharma-nutra and cosmeceutical industries with a market value of 212 million USD. Squalene is widely used as an antioxidant and as an adjuvant in vaccines. Currently over 50% of global squalene comes from the mass killing of deep-sea sharks (around 6 million) to meet annual demand with the remainder coming from plant oil sources that are erratic in terms of reliable production. Microalgae, photoautotrophic organisms which are the source of various value-added products, could be a potential candidate as an alternative to shark-based squalene. The present chapter discusses the ability of microalgae to produce squalene, its biosynthesis and possible microalgae-based biorefinery strategies for the sustainable production of squalene.