ABSTRACT
One of the most exciting families of medicinal plants to start with when prospecting the flora of the Asia–Pacific for drugs is the Annonaceae. Annonaceae are widespread in the tropical world as a broad variety of trees, climbers, or shrubs which are quite easily spotted by their flowers that have a pair of whorls of leathery petals and groups of club-shaped fruits containing several seeds in a row. There are three major types of active principles in this family: acetogenins, which often confer insecticidal properties, and isoquinolines and diterpenes of the labdane type. In Malaysia, a decoction of the roots is used as a drink to assuage stomachaches. It is most likely effective because of its content of isoquinoline alkaloids which are known to block the muscarinic receptors and therefore impede the secretion of gastric juices and the contraction of gastric smooth muscles.
