A substance of very wide occurrence. It is found dissolved
   in the sap of the roots and rhizomes of many composite and other
   plants, as Inula, Helianthus, Campanula, etc., and is extracted by
   solution as a tasteless, white, semicrystalline substance, resembling
   starch, with which it is isomeric. It is intermediate in nature between
   starch and sugar. Called also dahlin, helenin, alantin, etc.