Open-tubular gas chromatographic analysis of fatty acids in the lipids from the seeds of 20 species of Gymnospermae showed that they all contained nonmethylene-interrupted polyenoic (NMIP) acids as minor components and palmitic, oleie, linoleic and ~-linolenic acids as major components. The NMIP acids have an additional 5,6-ethylerdc bond in ordinary plant unsaturated fatty acids and the following C 2 elongation acids: eis-5, cis-9-octadeeadienoic acid (5,9-18:2) (I); 5,9,12-18:3 (II); 5,9,12,[15][16][17][18] 5,[11][12][13][14][15][16][17][18][19][20] 5,11,[14][15][16][17][18][19][20] and 5,11,14,[17][18][19][20]. The main NMIP acids found in neutral lipids are I in two species of Taxus, II in seven species of Pinaceae, III in two species of Podocarpaceae, Torreya nucifera, Cycas revoluta, and Ginkgo biloba, and III and IV in each of three species of Taxodiaceae, and Cupressaceae. The polar lipids constitute the minor fraction of seed lipids in general. The content and composition of NMIP acids in these lipids differ considerably fromthose in neutral lipids. Analysis of the partial cleavage products of triacylglycerois showed that the NMIP acids distribute mainly in the 1,3-position.Lipids 17: 716-723, 1982.

Analytical methods to obtain the detailed compositions of the fatty acids in oils containing more than one conjugated octadecatrienoic acid by open‐tubular gas liquid chromatography (GLC) and by reversed‐phase high performance liquid chromatography (HPLC) were established. Effective GLC separations ofcis,trans,trans‐9,11,13‐octadecatrienoic acid (ctt‐9,11,13–18∶3),ctc‐9,11,13–18∶3,ttc‐9,11,13–18∶3,ttt‐9,11,13–18∶3,ttc‐8,10,12–18∶3, andttt‐8,10,12–18∶3 were obtained with an opentubular column coated with the nonpolar liquid phase OV‐1 using an instrument having all‐glass carrier gas pathways. The HPLC method also gave satisfactory separations for the isomeric conjugated octadecatrienoates on the basis of number of thecis andtrans double bonds. Two or three minor conjugated trienoic acids were found along with the principal conjugated trienoic acid in tung oil, and seed oils of cherry,Prunus sp., Momordica charantia, Trichosanthes anguina, Punica granatum, Catalpa ovata, andCalendula officinalis. The mechanism for the formation of the conjugated trienoic acid mixtures in the seed oils is discussed. TheC. ovata seed oil also containedct andtt‐9,12‐octadecadienoic acids. Thett isomer is presumed to be a precursor ofttc‐9,11,13–18∶3, the main conjugated trienoic acid in this oil.

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The fatty acid compositions of lipids from two species of Crinoidea and two species of Ophiuroidea have been investigated with open‐tubular gas chromatography. About 5–10% of tetracosahexaenoic acid was found in total fatty acids from all the samples, and the structure was determined as all‐cis‐6,9,12,15,18,21‐tetracosahexaenoic acid [24∶6(n−3)] by13C‐NMR of the methyl esters and mass spectrometric analyses of the methyl esters, the pyrrolidides and the ozonolysis products. The 24∶6(n−3) was concentrated in the polar lipids rather than neutral lipids. The n−3 hexaenoic structure suggested chain elongation of 22∶6(n−3) as the source.The 5‐olefinic acids (5−18∶1, 5−20∶1, 5,11‐ and 5,13−20∶2) were low in Crinoidea (0.2–1.3%) but were present in higher levels (2.5–5.2%) in Ophiuroidea. Polyunsaturated acids found other than 24∶6(n−3) were 20∶4(n−6), 20∶5(n−3) and 22∶6(n−3) as major components and 16∶3(n−3), 18∶2(n−6), 18∶3(n−6), 18∶3(n−3), 18∶4(n−3), 20∶2(n−9), 20∶2(n−6), 20∶3(n−6), 20∶3(n−3), 21∶5(n−3) and 22∶5(n−3) as minor components in all the samples.

The positional distribution of acetic and butyric acids in bovine milk fat triacylglycerols was determined by chiral‐phase high‐performance liquid chromatography (HPLC) of the derived diacylglycerols. Enriched fractions of acetic and butyric acid‐containing triacylglycerols were isolated by normal‐phase thin‐layer chromatography (TLC) from a molecular distillate of butter oil, and they were fully hydrogenated. Mixedsn‐1,2(2,3)‐ andX‐1,3‐diacylglycerols of short‐ and long‐chainlength, which were generated by partial Grignard degradation of the hydrogenated triacylglycerols, were isolated by borate‐TLC. The enantiomericsn‐1,2‐andsn‐2,3‐diacylglycerols and theX‐1,3‐diacylglycerols as their 3,5‐dinitrophenylurethanes were resolved by HPLC on chiral columns. Both acetic and butyric acids were exclusively associated with thesn‐ 2,3‐ andX‐1,3‐diacylglycerols of short and long chainlength. These results establish the presence of acetic and butyric acids in thesn‐3‐position of bovine milk fat triacylglycerols. Other short‐and medium‐chainlength acids were found in progressively increasing proportions also in thesn‐1‐ andsn‐2‐positions.