Table 1

Sources and functions of fatty acids

n -3 seriesn- 6 series
SourceGenerally - vegetable oils; longer chained- fatty acids in phytoplankton and tranferred down the marine nutrition chain;α-linolenic acid (18:3n-3) also found in higher plant structural fats; eicosapentaenoic acid (20:5n-3) predominantly found in fish oilsGenerally derived from plants, grain and vegetable oils;linoleic acid (18:2 n-6) mainly in dietary vegetables and plant lipids - safflower, sunflower, soybean, borage, evening primrose; arachidonic acid (20:4n-6) predominantly in animal fats
FunctionPrecursors of signal molecules, constituents of membrane phospholipidsPrecursors of signal molecules, constituents of membrane phospholipids
DerivativesEicosanoids including series 5 leukotrienes LTB5, prostaglandins eg PGE3, PGI3, thromboxanes eg TxA3 Eicosanoids including leukotrienes eg LTB4, LTC4, prostaglandins eg PGE2, PGI2thromboxanes eg TxA2