Withanolide

Withanolides are a group of at least 300 naturally occurring steroids built on an ergostane skeleton.

It remains unknown to what end withanolides are produced; they may act as a deterrent for feeding insect larvae and other herbivores.

Genera within the nightshade family that produce withanolides include: Datura,[3] Iochroma,[4] Lycium,[5] Nicandra,[6] Physalis,[7] Salpichroa,[8] Solanum,[9] Mandragora,[10] Withania,[11] and Jaborosa.

Withaferin A, the first withanolide to be isolated, was found in winter cherry (Withania somnifera)[13] and Acnistus arborescens.

[14] Salpichrolides A, B and G (isolated from Salpichroa origanifolia) exhibit an inhibitory effect on the growth of larva of the Mediterranean fruit fly (Ceratitis capitata).