Constit. of Vitis vinifera (wine grape) Astilbin is a flavanonol, a type of flavonoid. It can be found in St John's wort (Hypericum perforatum, Clusiaceae, subfamily Hypericoideae, formerly often considered a full family Hypericaceae), in Dimorphandra mollis (Fava d'anta, Fabaceae), in the the leaves of Harungana madagascariensis (Hypericaceae), in the rhizome of Astilbe thunbergii, in the root of Astilbe odontophylla(Saxifragaceae) and in the rhizone of Smilax glabra (Chinaroot, Smilacaceae).