The Incorporation of Mevalonic Acid-2-C14 into the Triterpene Saponin of Zanthocephalum

Characterization of the toxic constitutent of perennial broomweed as a triterpene saponin by Shaver, Camp and Dollahite (1964) suggested that the compound may be formed by a known terpene biosynthetic path. If it could be established that the plant incorporates the terpene biosyntheUc intermediate, mevalonic acid, the existence of this biosynthetic route would be partially established. Two methods of administration of the suspected precursor were utilized in this incorporation study on perennial broomweed. The presence or absence of a saponin from three other related plant species, annual broomweed (Amphiachyrts dracunculoides) , sneezeweed (Helenium tenuVolium) and bitterweed (Actinea odoTClta) was determined.