Abstract
Examination was made of ceramide monohexosides (CMH) and sphingophosphonolipids (SPnL) from the viscera of Hemifusus ternatanus.
H. ternatanus belongs to Prosobranchia in animal classification, and is a popular sea snail in evolutional and biological respects.
Conjugated lipids were extracted with chloroform-methanol (2 : 1, by vol) following the method for simple lipids with acetone. CMH and SPnL as main sphingolipids were separated and purified using a silicic acid column. The purified sphingolipids were identified by TLC, fast atom bombardment mass spectrometry (FAB/MS), analysis of the degradation products and quantitative analysis of sugar, long chain base, phosphorus and fatty acid ester.
CMH consisted primarily of galactosylceramides (Gal-Cer), according to GC analysis of sugar in the water-soluble components. SPnL consisted of ceramide aminoethylphosphonate (CAEP) and ceramide N-methylaminoethylphosphonate (CMAEP) at 73 : 27 in positive ion mode FAB/MS and 93 : 7 in negative ion mode FAB/MS.. From GC analysis, the water-soluble component was mostly 2-amino-ethylphosphonic acid (AEP).
The major fatty acids of Gal-Cer were 2-hydroxyhexadecanoic (43.7%) and 2-hydroxyheptadecanoic acids (11.4%), and that of CAEP, hexadecanoic acid (64.1%). The ratio of non-hydroxy fatty acid to 2-hydroxy fatty acid was 1 : 3 in Gal-Cer and 8 : 1 in CAEP.
The major long-chain bases of Gal-Cer were C18-sphingatrienine (17.9%) and C18-sphinga-dienine (14.4%), and of CAEP, C18-sphingatrienine (17.6%) and C16-sphingosine (17.2%). The long chain bases of these sphingolipids in most cases were unsaturated long chain bases.
The most remarkable analytical result for the sphingolipids obtained from viscera of H. ternatanus was the finding of the large number of even-numbered unsaturated long chain bases and trienic dihydroxy bases as d18 : 3, d19 : 3 and d21 : 3.
