Fatty-acid synthesis in the echinoderms:Asterias rubens, Echinus esculentusandHolothuria forskali

Abstract

The fatty-acid compositions of tissue lipids ofAsterias rubensL.,Echinus esculentusL. andHolothuria forskaliDelia Chiaje were determined by means of gas-liquid chromatography. Considerable proportions of branched-chain, normal odd-numbered and eicosatetraenoic acids occur in the latter two animals. Tissues of all three animals were incubated with 1−¹⁴C-acetate. The relative specific activities of fatty-acid fractions isolated by thin-layer chromatography upon AgNO₃-impregnated silica gel G fell in the order: saturates > monoenes — dienes > polyenes. The fatty-acid compositions of the alkoxydiglyceride, triglyceride and phospholipid classes of A. rubens hepatic caecal lipid were also determined.