Abstract
Carotenoids, one of the most widespread pigments, are becoming increasingly important for humans because of various applications in human foods and animal feeds. Rising consumer awareness about the potential health benefits of carotenoids and the increasing interest in natural food products have benefited the carotenoid in-dustry. Microalgae are recognised as one of the most promising organisms for the commercial and sustainable production of carotenoids; however, the costs for the natural production of carotenoids are much higher than those for chemical production. Light quantity and quality play a crucial role in the biosynthesis of carotenoids. Hence, optimising light parameters is essential for the efficiency and reliability of carotenoid production. This review evaluates the importance of the various aspects of light, specifically light quality and quantity, in the synthesis of carotenoids in algae and discusses why light should be considered a critical factor in the industrial-scale production of carotenoids from algal cultures.