Identification of a xylose-containing cerebroside in the salt gland of the herring gull

[摘要] A pentose-containing cerebroside has been identified in the salt gland of the herring gull, using mass spectrometry of acetyl and trimethylsilyl derivatives. A detailed interpretation of the spectra allowed a conclusion concerning the major long-chain base (the C20 homolog of sphingosine) and the major fatty acids (C22–C25 2-hydroxy fatty acids), using reference spectra of synthetic galactosylceramides. A six-membered glycose ring (aldopyranose) was demonstrated by mass spectrometry of the acetyl derivative of periodic acid-oxidized and sodium borodeuteride-reduced pentosylceramide. By gas–liquid chromatography and mass spectrometry of methanolysis products, the pentose was shown to be identical with xylose. The procedures were applied to 25–50 μg of glycolipid.

[关键词] sphingosine;2-hydroxy fatty acids;pentosylceramide;periodic acid oxidation;sodium borodeuteride reduction;mass spectrometry