出版社：American Society for Biochemistry and Molecular Biology
摘要：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 μmole of lipid-bound sialic acid/100 ml; for rabbit plasma the value was 0.28 μmole/100 ml. The total bovine plasma ganglioside fraction contained equal amounts of N -acetylneuraminic and N -glycolylneuraminic 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 C20 isomer was detected.
