α-Eleostearic acid or (9Z,11E,13E)-octadeca-9,11,13-trienoic acid, is an organic compound, a conjugated fatty acid and one of the isomers of octadecatrienoic acid. It is often called simply eleostearic acid although there is also a β-eleostearic acid (the all-trans or (9E,11E,13E) isomer). Its high degree of unsaturation gives tung oil its properties as a drying oil.

Biochemical properties

In their pioneering work on essential fatty acids, George Burr, Mildred Burr and Elmer Miller compared the nutritional properties of α-eleostearic acid (ELA) to that of its isomer alpha-linolenic acid (ALA). ALA relieved essential fatty acid deficiency; ELA did not. In rats, α-eleostearic acid is converted to a conjugated linoleic acid. The compound has been found to induce programmed cell death of fat cells, and of HL60 leukemia cells in vitro at a concentration of 20 μM. Diets containing 0.01% bitter gourd seed oil (0.006% as α-eleostearic acid) were found to prevent azoxymethane-induced colon carcinogenesis in rats.

Sources

α-Eleostearic acid is found in the oils extracted from seeds. Tung oil has 82% α-eleostearic acid. Bitter gourd seed oil has 60% α-eleostearic acid.

Etymology

Eleo- is a prefix derived from the Greek word for olive, ἔλαιον.