Phospholipid studies of marine organisms: III. New phospholipid fatty acids fromPetrosia ficiformis

The fatty acyl components of the phospholipids from the sponge Petrosia ficiformis consisted predominantly of branched, especially iso and anteiso acids. The two major components of the complex mixture are the hitherto unknown Z,Z‐25‐methyl‐5,9‐hexacosadienoic and Z,Z‐24‐methyl‐5,9‐hexacosadienoic acids. Other unknown acids are: 7,13,16‐docosatrienoic acid, 15‐methyldocosanoic acid, 15‐methyltricosanoic acid and 24‐methyl‐5,9‐pentacosadienoic acid. Short branched‐chain fatty acids, presumably of bacterial origin, are considered to be the possible bioprecursors of these novel phospholipid constituents. The major phospholipids were PE, PC, PG, PS and PI. The distribution of fatty acids among the phospholipid classes was also studied.