STEROLS FROM GREEN AND BLUE-GREEN-ALGAE GROWN ON REUSED WASTE-WATER

Two green algae, Scenedesmus sp. and Chlorella vulgaris, and a blue-gr een algae, Spirulina maxima, grown in reused waste water were harveste d and identified as the major microalgae. The sterol composition was i nvestigated by GC, and the sterols identified by GC-MS. All algal spec ies were characterized by a specific sterol distribution with 24-methy l or 24-ethyl sterols as the major components. Ergosterol (41.7% of th e sterol mixture), 7-dehydroporiferasterol (13.5%) and 5-dihydroergost erol (13.2%) were the principal sterols of Chlorella vulgaris, whereas chondrillasterol (59.2%) and 7-chondrillastenol (23.5%) were found in Scenedesmus sp. 24-Ethylcholesterol (79.5%) predominated in Spirulina maxima which also exhibited a higher cholesterol content (8.5%) than the two green algae (1-2.5%).