Among all natural sources studied to date, Dunaliella possesses the highest content of 9- cis β-carotene [ 20 , 34 ]—reaching levels up to 100 g/kg DW , [ 19 , 37 , 38 ]; β-carotene-rich Dunaliella powder has been commercially exploited in many countries since the 1980s. Although many microalgae can produce xanthophylls, H. pluvialis is the one that accumulates them to the highest levels (., asthaxanthin [ 10 ]), so it is now cultivated at large scale by several companies using distinct approaches [ 39 ]. On the other hand, Muriellopsis sp. holds a high lutein content (up to 35 mg L −1 ), coupled with a high growth rate; hence, it has been exploited for commercial production of lutein [ 10 ]. Finally, C. ellipsoidea was reported to produce violaxanthin, together with two other minor xanthophylls, viz . antheraxanthin and zeaxanthin—whereas the main carotenoid in C. vulgaris was lutein [ 23 ]. Further pieces of related information are gathered in Table 1 .