Sesquiterpene lactones inhibitory effects

The ability of feverfew extract to inhibit 5HT-secretion in platelets was used to identify compounds responsible for the inhibitory effects on platelets [44], A crude feverfew extract was separated by chromatography and fractions were screened for antisecretory activity induced by adrenaline. In five active fractions compounds were identified as the sesquiterpene lactones parthenolide (1), canin (19), artecanin (20), secotanapartholide A (24) and 3 8-hydroxyparthenolide (2). The ability of parthenolide to affect platelet activity induced by other agents was confirmed in a study of direct comparison of crude feverfew extract with parthenolide [43], Parthenolide in the micromolar concentration range inhibited platelet 5HT-secretion. 

Encelin from Montanoa speciosa is inhibitory to growth and development of fungal cells of Mucor rouxii. Other cytotoxic sesquiterpene lactones from Montanoa tomentosa ssp. microcephala have been reported.45,46 A number of kaurane diterpenes and e/tf-kauranoids have been reported that are potentially useful because of their cytotoxicity against human tumor cells, anti-HIV activity, and trypanosomicidal activity.47 56 New structures are frequently discovered, and probably we will learn new effects in humans and animals in the future.57,58 Paradoxically, these plant natural products probably have specific and important effects in the plants, but we are still ignorant of these roles. 

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