Analysis of the total oil and fatty acid composition of seeds of some Boraginaceae taxa from Turkey

Abstract

Mature seed samples of twenty-four Boraginaceae taxa collected from their natural habitats in Turkey were analysed by GC for total oil content and fatty acid composition. The range of total fat in the taxa varied between 7.0 and 35.7%. The amounts of palmitic (16:0) and stearic (18:0) acids determined were 5.65–17.81 and 1.49–5.08%, respectively. Mono-unsaturated fatty acids were in the range 8.83–55.32% for oleic, 0.22–6.21% for eicosenoic, 0.04–8.94% for erucic, and 0.08–2.71% for nervonic acid. Poly-unsaturated fatty acids were between 1.41 and 68.44% for linoleic, 0.12 and 43.0% for α-linolenic, 0.04 and 24.03% for γ-linolenic, and 0.02 and 14.59% for stearidonic acid. Total saturated (9.3–23.7%), mono-unsaturated (10.59–73.28%), and poly-unsaturated fatty acids (13.91–68.78%) varied substantially. Total unsaturated fatty acids ranged from 70.12 to 90.29%. There were significant differences between fatty acid profiles at taxa (P < 0.05) at genera levels, based on mono-unsaturated and poly-unsaturated fatty acid concentrations (P < 0.05). Segregation at the generic level by principle-component analysis was accomplished based on nine major fatty acids. The fatty acid patterns, their relative proportions, and quantities of unusual fatty acids as additional biochemical markers seem to be useful in the taxonomy of Boraginaceae at generic and infrageneric levels. All taxa are, in general, rich in linoleic and α-linolenic acids as essential fatty acids for dietary reference intakes. Seed oils of Symphytum, Anchusa, and Trachystemon orientalis for γ-linolenic acid and Echium for both γ-linolenic and stearidonic acid may be evaluated as alternative wild sources.