Abstract

Gangliosides were isolated from human, bovine, and rabbit plasma and were quantified by gas-liquid chromatography.Purification was achieved by sequential use of partitioning in solvents, DEAE-Sephadex chromatography, base treatment, and silicic acid chromatography.Human and bovine plasma yielded slightly more than 1 pmole of lipidbound sialic acid/100 ml; for rabbit plasma the value was 0.28 pmole/l00 ml.The total bovine plasma ganglioside fraction contained equal amounts of N-acetylneuraminic and Nglycolylneuraminic acids, rabbit plasma gangliosides had about 1% of the latter, and the human plasma sample contained only the former.Thin-layer chromatography revealed important differences among the plasmas from the three species, but all possessed hematosides and hexosamine-containing gangliosides.The approximate ratios of these two categories, based on sialic acid content, were (hematosides : hexosamine-type) : human, 2 : 1 ; rabbit, 3 : 2; and bovine, 2 : 3. The fatty acid compositions of both categories were characteristic of extraneural gangliosides and included six major acids: palmitic, stearic, behenic, tricosanoic, lignoceric, and nervonic.The major long-chain base in each sample was sphingosine, while only a trace of the Czo isomer was detected.Supplementary key words hematosides .sialic acid fatty acids .sphingosine bases DEAE-Sephadex G m x L m s m E s were first recognized as constituents of blood by their discovery in erythrocytes by Yamakawa and Suzuki in 1951 (1).A recent report by Marcus and Cass (2) indicated the presence of lipid-bound