Isolation and determination methods for brain cerebrosides, hydroxy fatty acids, and unsaturated and saturated fatty acids *

A new method is described for the isolation of nearly pure total cerebrosides from fresh brain. Florisil columns are used to separate the cerebroside hydroxy and normal acids, in the form of their esters, and to separate the saturated and unsaturated esters of each group. The esters within each class are determined by gas chromatography, the hydroxy esters being run as the methyl ethers. Yields in the various steps are close to theoretical. The presence of lower homologues in all four classes of rat brain cerebroside acids was discovered. Particularly large amounts of C,, and C, saturated acids were found.