Lipids

• Fatty acids - aliphatic carboxylic acids which generally are found in natural fats and oils in esterified form.

Fatty Acids - Saturated (Cx:0) and Unsaturated (Cx:> 0)
Common Name	Shorthand Designationa	Series	Occurrence
Acetic	C2:0		endproduct of microbial fermentation
Propionic	C3:0		endproduct of microbial fermentation
Butyric	C4:0		butter; endproduct of microbial fermentation
Valeric	C5:0		butter; endproduct of microbial fermentation
Caproic	C6:0		butter; endproduct of microbial fermentation
Caprylic	C8:0		butter, some plant oils
Capric	C10:0		butter, some plant oils
Lauric	C12:0		butter, palm oil, coconut oil
Myristic	C14:0		butter, palm oil, coconut oil
Palmitic	C16:0		all plant oils and animal fats
Palmitoleic	cis-C16:1;9	w7	nearly all plant oils and animal fats
Stearic	C18:0		all plant oils and animal fats
Oleic	cis-C18:1;9	w9	all plant oils and animal fats
Elaidic	trans-C18:1;9	w9	hydrogenated oils/fats and ruminant fats
Linoleic	all-cis-C18:2;9,12	w6	corn, peanut, soy, cottonseed and many other plant oils
g-Linolenic	all-cis-C18:3;6,9,12	w6	some plants; animal fats
a-Linolenic	all-cis-C18:3;9,12,15	w3	many plant oils (particularly linseed oil)
Arachidic	C20:0		peanut oil
Arachidonic	all-cis-C20:4;5,8,11,14	w6	animal fats, peanut oil
Timnodonic [also known as Eicosapentanoic acid (EPA)]	all-cis-C20:5;5,8,11,14,17	w3	fish oils
Behenic	C22:0		seeds
Erucic	cis-C22:1;13	w9	rapeseed (canola) oil and mustard oil
Clupanodonic	all-cis-C22:5;7,10,13,16,19	w3	fish oils, brain phospholipids
Cervonic [also known as Docasahexanoic acid (DHA)]	all-cis-C22:6;4,7,10,13,16,19	w3	fish oils, brain phospholipids
Lignoceric	C24:0		peanut oil, cerebrosides
Nervonic	cis-C24:1;15	w9	cerebrosides
a Legend for the shorthand designation, Cx:y;a,b,c,d,e,f  where x indicates the number of carbon atoms in the fatty acid, y represents the number of double bonds, and, a,b,c,d,e,f  represent the location of the double bonds.

• Triacylglycerols (triglycerides) - fatty acid esters of glycerol.  Triacylglycerols are the major storage form of lipids (animal "fats" and plant seed "oils").
  

• Phospholipids - serve as the main lipid constituents of membranes.  With the exception of the sphingomyelins, phospholipids are phosphoacylglycerols.  Phosphatidic acid is one example of a phospholipid.  Another example is phosphatidylcholine.
  

• Glycolipids - widely distributed in all tissue types, but particularly plentiful in brain and nervous tissue.  The major glycolipids are glycosphingolipids (sphingolipids attached to one or more monosaccharides).

• Steroids - play many physiologically important roles.  Cholesterol is widely distributed in nervous tissue, as a major component of membranes and plasma lipoproteins.  Cholesterol also serves as a precursor for a wide variety of steroid hormones (eg., estrogen, progesterone, testosterone; also a precursor for vitamin D).
  

This page updated by G. R. Frank.