Jacaric acid, a linolenic acid isomer with a conjugated triene system, has a strong antitumor effect in vitro and in vivo

► Conjugated linolenic acid is a linolenic acid isomer with a conjugated triene system. ► Conjugated linolenic acid had a strong cytotoxic effect in tumor cells. ► Conjugated linolenic acid induced apoptosis via lipid peroxidation. ► Cytotoxic effects of fatty acids were dependent on intracellular incorporation. ► Jacaric acid had a strong preventive antitumor effect in vivo.