Δ6-Unsaturated fatty acids in species and tissues of the Primulaceae

Abstract

The Δ6-unsaturated fatty acids γ-linolenic acid (GLA; 18:3Δ6,9,12) and octadecatetraenoic acid (OTA; 18:4Δ6,9,12,15) were present in seed lipids of the tribe Primuleae, but not in other tribes of the Primulaceae. Within the genus Primula both fatty acids were present in seed lipids from 22 species (from 12 sections), with combined levels increasing from 1.1 to 27.4%. High levels of Δ6- unsaturated fatty acids were also present in leaves of ten species (from nine sections), but with lower levels generally being present in root lipids. In general, the levels of octadecatetraenoic acid were higher than that of γ- linolenic acid. The results indicate that Δ6-unsaturated fatty acids could be used as taxonomic markers within the genus Primula.