Abstract
The carotenoid composition in cells of a ketocarotenoid-producing alga, Chlorococcum, was investigated by high-performance
liquid chromatgraphy (HPLC). Astaxanthin (free and esters), adonixanthin (free and esters), canthaxanthin, b-carotene, lutein, and
some cis-isomers of ketocarotenoids were found. The alga Chlorococcum cells could produce a large amount of ketocarotenoid
esters, like the alga Haematococcus pluvialis. The esters of astaxanthin and adonixanthin, and free canthaxanthin were the major
carotenoids in the alga Chlorococcum cells, while astaxanthin alone was the major carotenoid in the alga Haematococcus pluvialis.
The alga Chlorococcum cells might synthesize astaxanthin from b-carotene via canthaxanthin and adonixanthin in parallel, respectively,
which was controlled by the culture conditions. # 2002 Elsevier Science Ltd. All rights reserved.
Keywords: Carotenoid; Astaxanthin; Alga; Chlorococcum; H