Distribution of lipids and fatty alcohols in the polymeric and nonpolymeric lipid fractions of 4-week-old tissue culture-grown Arabidopsis roots. A, Gas chromatography chromatograms of polymeric and nonpolymeric lipid fractions of roots from 4-week-old wild-type seedlings. Fatty alcohols are highlighted by dashed blocks. Major suberin monomers are identified in the polymeric fraction (top), while membranous fatty acids, hydroxycinnamates, and sterols are shown in the nonpolymeric fraction (bottom). X:Y indicates fatty acids with X carbon atoms and Y unsaturations, X:Y-OH indicates fatty alcohols, ωOH-X:Y indicates ω-hydroxy fatty acids, X:Y-DCA indicates α,ω-dicarboxylic fatty acids, and 2OH-X:Y indicates 2-hydroxy fatty acids. 16:X and 18:X indicate mono- plus polyunsaturated fatty acids with 16 and 18 carbons, respectively. IS, Internal standards. B, Amount (in percentage of total) of aliphatics (fatty acids and derivatives), phenolics, and sterols found in the polymeric fraction. VLCFA, Very-long-chain fatty acid (>C18). Each value is the mean of three to four biological replicates. C, Amount (in percentage of total) of fatty alcohols found in the polymeric fraction. Each value is the mean of three to four biological replicates.