Carotenoid profile of three microalgae/cyanobacteria species with peroxyl radical scavenger capacity.

Carotenoids from cyanobacteria Aphanothece microscopica Nageli and green microalgae Chlorella vulgaris and Scenedesmus obliquus were identified. The total carotenoid content, based on dry weight of biomass, of A. microscopica Nägeli, C. vulgaris and S. obliquus were 1398.88μg/g, 1977.02μg/g and 2650.70μg/g, respectively. A total of 23 different carotenoids were separated in all the extracts, the major ones being all-trans-β-carotene (29.3%) and all-trans-lutein (28.1%) in Scenedesmus; all-trans-echinenone (22.8%) and all-trans-β-carotene (17.7%) in Chlorella; all-trans-echinenone (28.3%) and all-trans-β-carotene (26.2%) in Aphanothece. The carotenoid extracts were shown to be a potent scavenger of peroxyl radical, with values of 31.1 (Chlorella), 14.0 (Scenedesmus) and 7.3 (Aphanothece) times more potent than α-tocopherol.