Quinine
Family Rubiaceae
Cinchona sp., quinines (Cin. sp 1), are species of evergreen shrubs or trees with simple entire and opposite leaves, and small fragrant pale yellow or pink flowers in terminal inflorescences. The bark of some species (Cin. sp 2) contains about 30 alkaloids, of which quinine and its isomere quinidine; and cinchonine and its isomere cinchonidine, are the most important.
Use
Quinine, of which the content in the bark varies from 4-13%, was for a long time the most important drug in the treatment of malaria. Only after World War II, when synthetic drugs were developed, it lost its importance. Some quinine is still used in tonic and in a few other preparations like sunburn lotions.
Four species of Cinchona provide quinine, all natives of the South American Andes region. The use of the bark in curing malaria was known to the Indians from early times. The Jesuits were the first Europeans who discovered the use of the bark, and in 1739 Linnaeus received the first botanical specimens. Between 1850 and 1860 Dutch and British expeditions obtained plants in South America in an attempt to start cultivation in Java and India, but with little success as the plants died. The Indians kept the place where the tree was growing secret, so it was very hard to obtain new seeds or plants. Only after the Dutch were able to buy a large amount of seeds, they succeeded in growing the tree in Java. This species was found to have a high quinine content and was called Cinchona ledgeriana, after the Australian Ledger who sold the seeds to the Dutch. From 1864 plant material was exchanged between Java and India and large-scale cultivation was started. Around 1900 the plant was introduced into East Africa.
After about 10 years, when the bark contains the maximum quinine content, the trees are harvested. Roots, stems and branches are beaten with sticks to detach the bark from the wood, after which the bark is peeled of and dried in the sun.