Fatty Acids and Derived Compounds
Secondary fatty acids
some primary fatty acids are accumulated in unusual quantities, e.g., myristic acid in palms
Unusual starter units
iso and anteiso-
these are common, but almost always in small amounts
other types are less common
Unusual patterns of substitution
these are relatively common. Unsaturation in the Δ-9,10-position is most common. Additional sites of unsaturation usually are interupted by a methylene group as in linoleic acid.
some unusual sites of unsaturation are found in acids such as petroselenic acid (Δ-6)
γ-Linolenic acid is a component of many health food formulations.
In chloroplasts, the main acid is E-3-hexadecenoate.
Hydroxyfatty acids
these also are common ricinoleic acid is about 90% of the fatty acids of castor oil (in triglycerides)
requires NADH and O2
oleyl-CoA -----> ricinoleic acid
dihydroxy acid synthesis often is associated with epoxyfatty acid biosynthesis
Epoxyfatty acids
linoleic acid ----> vernolic acid
vernolic acid gives rise to 12,13-dihydroxyoleic acid
Methyl branched, cyclopropanoid and cyclopropenoid fatty acids
SAM is one precursor
Cyclopropenoid fatty acids
distributed in the family Malvaceae (including the Sterculiaceae and Bombacaceae).
Cyclopentenoid fatty acids
found in the Flacourtiaceae
Fluorofatty acids
fluoroacetate in Acacia, Gastrolobium, Oxylobium
longer fa's especially in seeds of Dichapetalum
fluoroacetate inhibits the TCA cycle.
Glycolipids
occasionally accumulated in seeds. Some grasses. These are important in the physical properties of flours.
Metabolically altered fatty acids
Essential oils
α,β-oxidation followed by either oxidation or reduction
esters, aldehydes, alcohols, alkenes, alkanes, etc.
Green leaf volatiles
Synomones
Kairomones Allomones
Jasmonic acid and methyl jasmonate
these are widespread in plants, are structurally similar to prostaglandins and serve as signal molecules in plants
Prostaglandins in animals
Prostaglandin biosynthesis is responsible for an unsaturated fatty acid requirement in animal diets
Algal pheromones
Insect pheromones
these often have structures based on fatty acids (some are terpenes), but they are synthesized in the insects themselves.
brevicomin and frontalin are of complex biosynthetic origin, but derived from fatty acid precursors
Mammalian pheromones
Many of these are fatty acid-derived.
Molecular biology
Fatty acids have been used by molecular biologists because the basic pathways are present in most plants, making possible changes to desired products with a minimum number of gene changes. The products are usually accumulated in large amounts. Many of the unsaturated and epoxyfatty acids have strong commercial demand.
Unusual Unsaturated Fatty Acids
Formation of Cyclopropenoid Fatty Acids
Cyclopropenoid and Cyclopropanoid Fatty Acids
Biosynthesis of Cyclopentenoid Fatty Acids
Products of Fatty Acid Metabolism
Jasmonic Acid and Related Compounds
Unusual Fatty Acids and Amides
