9(E),11(E),13(E)-Octadecatrienoic acid (β-ESA) is a conjugated polyunsaturated fatty acid that is found in plant seed oils and in mixtures of conjugated linolenic acids synthesized by the alkaline isomerization of linolenic acid. It reduces growth of Caco-2 colon cancer cells in a dose-dependent and time-dependent manner. In vitro, β-ESA induces DNA fragmentation and upregulation of pro-apoptotic Bax mRNA. β-ESA decreases protein expression of the apoptosis suppression factor Bcl-2 and induces apoptosis in T24 bladder cancer cells via production of reactive oxygen species. It also inhibits bacterial fatty acid dioxygenase with a Ki value of 49 nM in vitro.

In vitro, β-ESA induces DNA fragmentation and upregulation of pro-apoptotic Bax mRNA. β-ESA decreases protein expression of the apoptosis suppression factor Bcl-2 and induces apoptosis in T24 bladder cancer cells via production of reactive oxygen species. It also inhibits bacterial fatty acid dioxygenase with a Ki value of 49 nM in vitro.