The group of toxic triterpenoids in Lantana camara that can poison grazing livestock is lantadenes.
Lantadenes are naturally occurring pentacyclic triterpenoids, with lantadenes A and B among the most abundant and biologically active forms in Lantana camara leaves. When cattle, sheep, goats, horses, or other grazing animals eat the plant, these compounds can cause liver injury and photosensitivity: sunlight then triggers severe skin damage because impaired liver function leaves photoreactive pigments in circulation.
The poisoning story helped establish the chemistry. In 1941, researchers documented jaundice and the characteristic “pink-nose” inflammation in sheep fed Lantana camara. An active substance was isolated in 1943 and initially called lantanin; it was renamed lantadene A in 1948. Lantadene B was identified around the same period, and later structural work involved chemist Derek Barton.
Lantadenes are sometimes confused with generic plant saponins or coumarins, but they belong specifically to the pentacyclic triterpenoid class. The plant’s toxicity also varies with the plant part, growth stage, and animal species, so not every exposure produces the same severity.