Аннотация:Algae are indispensable resources for food, bioactives, nutraceuticals, pigments, bioenergymolecules, biofertilizers, and agents for bioremediation. They are also the primary sources ofnutrients to aquatic and semiaquatic organisms supporting a number of life forms. The presentday challenges in meeting food security are compounded by issues of climate change,demanding sustainable sources of food and food ingredients. In this context the food additivesfrom microalgae are of prime importance as they can be grown autotrophically in anecofriendly manner. Algae are also sources of novel molecules of high economic value,namely, specialty lipids, carbohydrates, pigments, and secondary metabolites. Carotenoidsassume importance as the major natural pigments from algae. Algal forms are rich sources ofβ carotene, which is the precursor of vitamin A. They also produce α-carotene, lycopene,β-cryptoxanthin, lutein, zeaxanthin, astaxanthin, and a range of esters. Carotenoids in generalexhibit antioxidant properties, and the most potent of them all is astaxanthin.In view of the importance of astaxanthin as a pigment and health-promoting compound, it isone of the most highly researched molecule in the recent times. It is produced not only bymicroalgae but also by few microorganisms. Astaxanthin’s demand as a pigment source ismainly met by the synthetic chemistry processes; however, from the biological activity pointof view, the astaxanthin esters are of greater value. The natural sources provide the muchneeded high quality astaxanthin and its derivatives; however, it is expensive to extractand purify, compared with its substitutes produced from synthetic chemistry route.Crustaceans are popular sources of these molecules by virtue of their ability to accumulatethe pigment through dietary means by feeding on phytoplanktons rich in astaxanthin andits esters.This volume is intended to provide a holistic understanding of the biological sources ofastaxanthin and the biomass production technologies coupled with downstream processing forisolating the pigment for various applications.