The content and fatty acid (FA) composition of FA neutral acylglycerols (NAG), a mixture of 1,2,3‐triacyl‐sn‐glycerols (TAG) and 3‐acetyl‐1,2‐diacyl‐sn‐glycerols (acDAG), were determined in the seeds and arils of fruits of 14 Euonymus L. species. On the average, the seeds exceeded the arils in the absolute and relative dry matter content 2.9‐ and 1.9‐fold, respectively, and separate plant species greatly differed in NAG composition. The proportions of TAG in the NAG of seeds and arils were 4–5 and ~98 %, respectively. The degree of FA unsaturation in aril NAG was higher than in the seed NAG, and in acDAG—higher, than in TAG. In the NAG, 14 major FA molecular species (excluding minor FA) were found, and linoleic, oleic, palmitic, and linolenic acids were predominant. NAG of separate taxonomic units of the genus Euonymus L. differed from each other in the concentration of major FA as well as other FA. So, by using statistical analysis, it was definitely established that the species from the subgenus Euonymus were characterized by an increased content of linoleic acid, while those from the subgenus Kalonymus, by the predominance of oleic acid. Meanwhile, the species of the section Euonymus were marked by an enhanced concentration of a number of hexa‐ and octadecenoic FA positional isomers.

The triglyceride composition of linseed oils obtained under different ecological conditions and having different fatty acid compositions was determined by a combination of several chromatographic techniques. The triglyceride mixture was first separated in 8 fractions of different polarity by reversed‐phase paper chromatography. Each glyceride fraction was then separated in a partition chromatographic system as the triglyceride coordination complexes with silver ions into individual compounds. The fatty acid compositions of the original oil, single glyceride fractions, and individual triglycerides were determined by gas‐liquid chromatography. The molar ratio between the two neighboring glyceride fractions was determined by relating the fatty acid composition of each fraction to the fatty acid composition of their sum. The triglyceride composition of the total oil was then calculated from these results. The presence of 18舑19 triglycerides was ascertained in the samples studied, and the molar concentration of each glyceride was estimated. Linseed oil contains only triunsaturated and monosaturated‐diunsaturated triglycerides. Within each of these types the fatty acid distribution is close to random. At the same time, the content of some triglycerides departed regularly from a random pattern. A method for calculation of linseed oil triglyceride composition from the fatty acid composition is given. The same general pattern of glyceride formation in linseed is followed regardless of ecological conditions; therefore, the qualitative and quantitative triglyceride composition reflects the differences in fatty acid composition of linseed oil.

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Positional‐species composition (PSC) of 1,2,3‐triacyl‐sn‐glycerols (TAG) from the arils of mature fruits of 13 species of Euonymus L. genus was established. The residues of six major fatty acids (FA), palmitic, stearic, hexadecenoic (H), octadecenoic (O), linoleic (L), and linolenic, were present in the TAG. PSC of TAG was determined by their partial lipase hydrolysis. By using hierarchical cluster and principal component analyses, it was definitely demonstrated that separate taxonomic units forming this genus were significantly distinguished as regards PSC of TAG. In particular, the Euonymus subgenus greatly exceeded the Kalonymus subgenus in both total content of L in TAG and in the rate of its incorporation into their mid‐position, while TAG of Kalonymus were marked by a prevalence of O‐TAG and sn‐2‐O isomers. Thus, these subgenera were significantly distinct in the rate of incorporation of O and L residues in the sn‐2 position of TAG molecules. Meanwhile, the TAG from the Euonymus section species were marked by an enhanced concentration of H and the incorporation of H in UUU TAG was much more active than in other TAG types. As for positional‐type composition of TAG, saturated FA were always virtually absent in the sn‐2 position of Euonymus aril TAG.

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