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General description:
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Cinchona is a genus containing about 23 species native to mountains in South and Central America. Two species, Cinchona calisaya and Cinchona pubescens are important in the commercial production of the antimalarial drug quinine. Cinchona calisaya produces high levels of quinine, but is relatively slow growing. Cinchona pubescens grows more quickly, but produces lower levels of quinine. Much commercial production on plantations now found throughout the world involves hybrids between these and other Cinchona species.
Cinchona plants are shrubs or small trees. They produce clusters of white to purple flowers which are pollinated by hummingbirds and butterflies. Fruits are capsules with seeds dispersed by wind.
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History, uses and importance:
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Quinine played an important role in world history as one of the first effective treatments for malaria. Malaria has been one of the deadliest infectious diseases throughout history. Although malaria was not present in the New World prior to European colonization, Amerindians soon discovered the use of cinchona bark as a treatment for malaria. Jesuit missionaries in Peru learned of its use in the 1620s, and in 1630 it was used to treat the Countess of Cinchon, for whom the genus is named. Following her recovery, cinchona bark was introduced to Europe and around the world. For the next two centuries cinchona bark was widely harvested and exported under Jesuit control, although there was little understanding of which species were most effective (due to some taxonomic confusion, Cinchona officinalis has been reported as a source of quinine although this species actually produces very little quinine). In the 19th century, seeds of Cinchona were exported and used to establish plantations in other tropical regions. With technological advances in chemistry it became possible to identify plants with higher quinine yields, and to breed plants for increased quinine production. Widespread quinine production has saved millions of lives over the last 400 years. Quinine is still widely used even though other drugs for treating malaria were discovered beginning in the 1920s and malaria parasites have increasingly become resistant to quinine treatment. Quinine is also used to flavor tonic water, which was originally produced to prevent malaria, although tonic waters produced today have relatively low quinine levels.
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