SATURATED AND UNSATURATED STEROLS OF NITROGEN-FIXING BLUE-GREEN ALGAE (CYANOBACTERIA)

Article abstract of DOI:10.1016/0031-9422(88)80434-5

Five species of filamentous nitrogen-fixing blue-green algae (Cyanobacteria), (Anabaena cylindrica, Anabaena solitaria, Anabaena viguieri, Nostoc carneum, Nodularia harveyana) were grown in a freshwater medium containing 10percent seawater(DS medium).The sterols were analysed by means of a newly developed procedure involving precipitation with digitonine, GC and GC/MS but not TLC and CC.All species were found to synthesize a great variety of sterols (11-15 compounds).The digitonin precipitable sterols made up ca 0.005-0.03percent of the dried algal biomass.Remarkably, each species produced the saturated sterols, 5α-cholestan-3β-ol, 24-methyl-5α-cholestan-3β-ol and 24-ethyl-5α-cholestan-3β-ol.The latter was the main sterol in all organisms.Furthermore, the investigated microalgae were found to synthesize known C27, C28 and C29 sterols.Key Word Index-blue-green algae; nitrogen-fixing blue-green algae; sterols; cyanobacteria.