Biochemistry of the sphingolipids. XIV. Inositol lipids of flaxseed

A study has been made of the inositol-containing lipids of flaxseed phosphatides. Solvent fractionation procedures have been developed for the preparation of an inositol lipid fraction from the oil-free phosphatide. By countercurrent extraction, the inositol lipid fraction was separated into a crude phosphatidyl inositol fraction and a second fraction containing long-chain base nitrogen. The phosphatidyl inositol was shown to exist as a mixed magnesium-calcium salt and evidence is presented that nitrogenous impurities (mainly phosphatidylethanolamine) may be bound to phosphatidyl inositol through a chelated salt linkage. The long-chain base fraction was shown to contain phosphatidyl inositol and two phytoglycolipids, one similar to that from corn and soybean; the other of a novel type in which the oligosaccharide portion contains galactose, arabinose and fucose. The long-chain base in flax phosphatides was shown to be dehydrophytosphingosine. It was suggested that phytoglycolipid may exist in a loose complex with phosphatidyl inositol (possibly as a chelated magnesium and/or calcium salt). © 1962, The American Oil Chemists' Society. All rights reserved