γ-Linolenic and stearidonic acids in Mongolian Boraginaceae

Seeds of nine Central Asian species of Boraginaceae were investigated for the first time for their oil content and for the fatty acid composition of their seed oils by capillary gas chromatography. Levels of γ-linolenic acid ranged from 6.6 to 13.0% and levels of stearidonic acid ranged from 2.4 to 21.4% of total seed fatty acids. The seed oil ofHackelia deflexa exhibited the highest stearidonic acid content (21.4%) that has been found so far in nature. Other high contents of this fatty acid were in threeLappula species (17.2 to 18.1%). Seed oils ofCynoglossum divaricatum andAmblynotus rupestris contain considerable amounts ofcis-11-eicosenoic (5.3 to 5.8%) andcis-13-docosenoic acid (7.0 to 9.7%) besides γ-linolenic (10.2 to 13.0%) and stearidonic acid (2.4 to 6.5%), which distinguish these oils from those of other Boraginaceae genera. This paper was presented as a poster at 10th Minisymposium and Workshop on Plant Lipids, Sept. 3–6, 1995, in Berne, Switzerland.