COMPOSITION OF GLYCOLIPIDS IN DOG INTESTINE

Whole lipid extracts of dog small intestine were chromatographed on silicic acid, yielding all the glycolipids in three major fractions. Five classes of glycolipid were isolated in high yield from the fractions by column chromatography with Florisil, DEAE-cellulose, and silicic acid and by thin-layer chromatography. Cerebrosides, ceramide di-, tri-, and pentahexosides, and gangliosides were isolated in amounts of 0.162, 0.098, 0.041, 0.070, and 0.171 μmoles 8 per g of fresh tissue, respectively, and 0.026 μmole-/g of sulfatide was found by direct analysis. A minor glycolipid fraction, estimated at 0.014 μmole/g, contained longer oligosaccharide chains. This fraction was separated from all other lipids and appeared to be a mixture of ceramide hexahexosides containing glucose, galactose, hexosamine, and fucose. These seven classes of lipids accounted for 82% of the original whole lipid hexose, and the remaining 18% was distributed among unresolved side fractions. All the isolated lipids were glycosides of glucosylceramide with long-chain fatty acids. The intestine glycolipids are distinguished from those of several other tissuesby the absence of ceramide tetrahexosides and presence of penta- and hexahexosides. © 1969, American Chemical Society. All rights reserved.