The extraction of inositol-containing phospholipids and phosphatidylcholine from Saccharomyces cerevisiae and Neurospora crassa.

By use of fungi grown in the presence of [3H]-inositol and [14C]choline, we have explored methods for the quantitative extraction of inositol-containing phospholipids and phosphatidylcholine. Slightly alkaline mixtures of both ethanol-water and ethanol-diethylether-water at elevated temperatures were shown to effectively extract these lipids from intact Saccharomyces cerevisiae and Neurospora crassa. Some previously published procedures fail to completely extract to very polar phosphoinositol-containing sphingolipids of these organisms. Trichloroacetic acid can be used with caution in killing cells prior to extraction; lipid destruction can occur at elevated concentrations and temperatures. Complete extraction of these very polar lipids with polar solvents also results in an extract containing significant amounts of non-lipids.