Algal Carotenoids

Abstract

Summary Carotenoids are synthesized de novo by algae, photosynthetic plants and fungi. They are isoprenoid molecules that are responsible for various colors of fruits and vegetables such as yellow, orange and some red variants. Carotenoids are lipophilic compounds. These compounds can be classified into two categories ? carotenes and xanthophylls. A variety of macroalgae and microalgae are rich in carotenoids and they help in the absorption of sunlight. These carotenoids are also used as food pigments industrially in dairy products, beverages, among others as feed additives. They also find application in cosmetics and in pharmaceuticals given the growing demand for natural products in these sectors. Some carotenoids also provide provitamin A. Producing carotenoids from algae brings with it several advantages. For instance, it is easy to produce, cost-effective, and environmentally friendly. Their extraction with higher yields is easier and raw materials are not scarce or have seasonal constraints. Of late, there has been an increase in interest in dietary carotenoids due to their ability to reduce incidence of some chronic diseases that involve free radicals as well as for their antioxidant properties. It is likely that carotenoids protect cells from oxidative stress by quenching singlet oxygen damage through a variety of mechanisms. As such carotenoids that have been derived from algae could be a strong natural resource in the search for good functional ingredients. In this chapter, we discuss the structure of various algal carotenoids, their distribution and potential applications for human health.