SEED FATTY-ACIDS, FRONT-END-DESATURASES AND CHEMOTAXONOMY - A CASE-STUDY IN THE RANUNCULACEAE

In many plants the seed lipid composition differs from that of the lip ids in photosynthetic tissue. Unusual fatty acids are often present in the seed fat, but absent in leaves and other parts of the plant. The presence or absence of chemotaxonomically significant fatty acids can provide clues to a closer or less close relationship between plant spe cies, genera or families. The chemotaxonomic significance of a number of unusual fatty acids is discussed by way of examples from different plant families. Particularly interesting is the situation in the famil y Ranunculaceae, which is considered to be a rather primitive plant fa mily by many botanists. Gas chromatographic <<fingerprints>> indicate a large number of unusual fatty acids in seed lipids from this plant f amily. These unusual fatty acid patterns are highly characteristic. A number of Delta 5- and Delta 6-fatty acids were found only in one genu s or in a few closely related genera. Other unusual fatty acids were t ypical for other genera.