Crude extracts from the aerial parts of Lychnophora granmongolense (Asteraceae) were bioassayed for trypanocidal (trypomastigote forms of Trypanosoma cruzi) and analgesic (writhing test) activities. The crude ethyl acetate extract from the leaves plus inflorescences exhibited trypanocidal activity but no analgesic activity in the writhing model of pain. The bioassay-guided fractionation of this extract yielded three trypanocidal compounds: the sesquiterpene lactones centratherin (lychnophorolide A) and goyazensolide and the flavonoid eriodictyol. The flavonoids homoeriodictyol, eriodictyol 7, 3'-dimethyl ether, velutin, chrysoeriol, dihydroisorhamnetin, rhamnazin and the sesquiterpene lactone lychnophorolide B were also isolated from the ethyl acetate extract. Such flavonoids did not show any trypanocidal activity. The isolated amount of lychnophorolide B was not enough to account for the full activity against T. cruzi.
Copyright 2000 John Wiley & Sons, Ltd.