Peptic ulcers can be caused by food, stress, genetic, and environmental factors, 1) including Helicobacter pylori infection, abuse of steroidal-or non-steroidal anti-inflammatory drugs (NSAIDs), irregular eating habits, smoking, alcohol consumption, and psychological stress.2) Peptic ulcers result from defects in the mucosa and muscularis mucosa, as well as oxidative stress due to the increase of reactive oxygen species (ROS). 3) In Korea, the leaves of Ligularia stenocephala MATSUM. et KOIDZ. (Family Compositae) are consumed as an edible vegetable and used as a Chinese folk medicine for the treatment of edema and scrofula. 4) In eastern and western Asia, the genus Ligularia is used for the treatment of influenza, cough, ulcer, and tuberculosis. 5) Yoon et al. have reported that the leaf extract of L. stenocephala showed the highest antithrombotic activity among large numbers of edible and herbal plants.6) The root of L. stenocephala contain benzofuran derivatives (ligulachepalins, euparin, hydroxytremetone, 7) 5,6-dimethoxy-2-isopropenylbenzofuran, 8) and stenocephalain, 9) as well as two caffeoylquinic acid derivatives, 3,4-dicaffeoylquinic acid and 3,5-dicaffeoylquinic acid).6) However, caffeoylquinic acid levels of those plants have not been studied.Although L. stenocephala has been traditionally used to treat gastric cancer or gastric ulcers, these biological activities have not been scientifically verified. Therefore, we intended to find the preventive activity of the caffeoylquinic acid-rich fraction with potent peroxynitrite scavenging effect on the ulcers induced by HCl/ethanol-and indomethacin/ bethanechol-induced in mice. In addition, we attempted to find whether or not the wild vegetables such as Ligularia species containing high level of caffeoylquinic acids are beneficial for ulcer disease. The methanolic extract of L. stenocephala together with its BuOH-and Et 2 O soluble fractions were evaluated for their anti-ulcerogenic activity using mice, with the BuOH extract showing the best activity. The BuOH fraction contained 5-O-caffeoylquinic acid, 3,5-di-O-caffeoyl-muco-quinic acid, and 3,5-di-O-caffeoylquinic acid from HPLC analytical data.In Korea, three Ligularia species, Ligularia stenocephala, L. fischeri, and L. fischeri var. spiciformis, are used as edible vegetables. The three herbs are similar taxonomically and are called gondalbi, gomchwi and numchwi, respectively, in Korea. Distinguishing these species may be improved with HPLC chromatograms. Other Compositae family members also contain caffeoylquinic acids, including Aster species, 10) and Solidago species, 5,11) as well as L. stenocephala, 6) and L. fischeri var. spiciformis. 11)Caffeoylquinic acid chemically consists of the two parts of quinic acid moiety and phenylpropanoid moiety. The most common parent skeleton of those compounds is quinic acid while muco-quinic acid or epi-quinic acid are also uncommonly found. The most common phenylpropanoid is caffeic acid while the less common ones are p-coumaric acid and ferulic acid. Caffeoylqui...