Isolation and characterization of novel 2‐hydroxy fatty acids from the phospholipids of the spongeSmenospongia aurea

Abstract
The Caribbean spongeSmenospongia aurea revealed the presence of six novel branched α-hydroxy fatty acids: 2-hydroxy-17-methyloctadecanoic acid, 2-hydroxy-21-methyldocosanoic acid, 2-hydroxy-22-methyltricosanoic acid, 2-hydroxy-22-methyltetracosanoic acid, 2-hydroxy-24-methylpentacosanoic acid, and 2-hydroxy-23-methylpentacosanoic acid. These novel α-hydroxy fatty acids were associated with phosphatidylethanolamine. The spongesAplysina lacunosa andAplysina fistularis also contained considerable amounts of α-hydroxy fatty acids, the very long-chain 5,9,23-tricontatrienoic acid (30∶3), and phytanic acid. The sterol composition of the three sponges was also studied. It indicated thatA. lacunosa andA. fistularis contained large amounts of aplysterol and verongulasterol, whileS. aurea did not show any of these sterols. The results are discussed in terms of the taxonomy of the species.