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Plant cells in culture are capable of incorporating exogenous 1-O-alkyl-sn-glycerols into various neutral and ionic ether lipids. 1-O-Alkyl-2-acyl-sn-glycero-3-phosphocholines, the major class of compounds thus formed, are used for the preparation of platelet activating factor (PAF) in high yields. Similarly, the prochiral 2-O-alkyl-sn-glycerols are transformed to chiral 2-O-alkyl glycerophospholipids from which compounds can be obtained that exhibit antiviral activity in plant and animal cells. Reaction of 1-O-alkyl-2-acyl-sn-glycero-3-phosphocholines with phospholipase D in the presence of ethanolamine leads to 1-O-alkyl-2-acyl-sn-glycero-3-phosphoethanolamines, which serve as starting material for the preparation of 1-O-alkyl-2-acyl-sn-glycero-3-phospho-(N-acyl)ethanolamines, compounds known to have antitumor activity.

Incubation of photomixotrophic cell suspension cultures of rape (Brassica napus) and heterotrophic cell suspension cultures of soya (Glycine max) with 1-O-[1'-14C]hexadecyl-sn-glycerol or rac-1-O-[1'-14C]hexadecylglycerol leads in high yield (up to 78%) to labeled 1-O-hexadecyl-2-acyl-sn-glycero-3-phosphocholines. Alkaline hydrolysis of the choline glycerophospholipids yields pure 1-O-[1'-14C]hexadecyl-sn-glycero-3-phosphocholine. 1-O-[1'-14C]Hexadecyl-2-acetyl-sn-glycero-3-phosphocholine (platelet activating factor) is obtained by acetylating the lyso compound. The semi-synthetic preparation described leads to labeled platelet activating factor in an overall yield of 50-60% without loss of specific activity.

Lipids from callus cultures and suspension cultures of higher plants constitute 5 to 8% of the dry tissue's weight. The predominant lipid classes are the sterols, steryl esters, steryl glycosides and esterified steryl glycosides. Considerable amounts of a variety of sterylglycolipids, whose structures are not completely elucidated, are also present. Triglycerides and phospholipids occur in small proportions, whereas monogalactosyl diglycerides, digalactosyl diglycerides and sulfoquinovosyl diglycerides are present only in traces, if at all. Beta-Sitosterol is the predominant constituent sterol, stigmasterol and campesterol as well as a variety of as yet unidentified sterols occur in smaller proportions. The major constituent fatty acids are palmitic, oleic, linoleic and linolenic acids. Saturated very long-chain fatty acids are found in smaller proportions. Unusual fatty acids, such as epoxy acids, which occur in the seed lipids of certain plants, are not found in tissue cultures derived from these plants. Clucose and traces of galactose are the only sugars obtained by acid hydrolysis of the glycolipids occurring in plant tissue cultures.

The environmental conditions prevailing during growth of plant tissue cultures affect the concentration of certain lipid classes and the fatty acid patterns of the total lipids. Irrespective of whether the cultures are grown under continuous illumination or in the dark, aerated cultures contain larger proportions of sterols, steryl esters, steryl glycosides and various sterylglycolipids and lower concentrations of squalene than non-aerated cultures. The lipids of the latter contain larger proportions of saturated very long-chain fatty acids than those of the former cultures.