Cis and Trans isomers of 4-hydroxy-8-sphingenine in plant cerebrosides

Pure cerebroside was isolated from hay and concentrate (extracted oilseed used for cattle feed), and the composition of the long-chain bases determined. The principal base was the cis isomer of 4-hydroxy-8-sphingenine (t18: 1 ^8c) which has not been reported before. The other trihydroxy bases were t18: 1^8t and t18: 0.Allylic and non-allylic dihydroxy bases were found in concentrate cerebroside and identified as d18: 1⁴, d18: 2^{4, x}, d18: 0 and d18: 1^x (x = 8?). Cis and trans isomers of mid-chain double bonds (position x) were tentatively identified, and the dihydroxy bases are probably identical to those recently found in wheat flour cerebroside 2].