COMPARATIVE-STUDY OF THE ENDEMIC FRESH-WATER FAUNA OF LAKE BAIKAL .6. UNUSUAL FATTY-ACID AND LIPID-COMPOSITION OF THE ENDEMIC SPONGE LUBOMIRSKIA-BAICALENSIS AND ITS AMPHIPOD CRUSTACEAN PARASITE BRANDTIA-(SPINACANTHUS)-PARASITICA

Lipids and phospholipids (both plasmalogen and alkyl forms) of the freshwater sponge Lubomirskia baicalensis and the sponge's gammarid parasite Brandtia (Spinacanthus) parasitica were examined. Composition of alkenyl-acyl (plasmalogen), alkylacyl and diacyl forms of major phospholipid classes, phosphatidylethanolamine and phosphatidylcholine were determined. One hundred and eighty-three fatty acids were identified by CC-MS: 46 saturated, 55 monoenoic, 35 dienoic, 25 trienoic and 22 tetra-, penta- and hexaenoic. The freshwater sponges, belonging to the family Lubomirskiidae, were shown to contain unusual long-chain fatty acids: anteiso-5, 9-28:2, branched-5, 9-29:2, 5,9,23-29:3, 5,9,23-30:3, 15,18,21,24-30:4 and 15,18,21,24,27-30:5. Some from these fatty acids were found in lipids of the amphipod parasite.