9Z,11E,13E-Octadecatrienoic Acid ethyl ester

A conjugated polyunsaturated fatty acid commonly found in plant seed oil which accounts for about 70% in tung oil and 60% of the total fatty acid composition of bitter gourd seed oil. α-ESA is metabolized and converted to conjugated linoleic acid (9Z,11E-CLA) in rats. It has shown potential as a tumor growth suppressor. In colon cancer Caco-2 cells, α-ESA induced apoptosis through up-regulation of GADD45, p53, and PPARγ. In DLD-1 cells supplemented with α-ESA, apoptosis was induced via lipid peroxidation with an EC₅₀ of 20 µM. It also inhibits DNA polymerases and topoisomerases with IC₅₀s ranging from ~5-20 µM for different isoforms of the enzymes. α-ESA ethyl ester is a neutral, more lipid soluble form of the free acid.