Ethnobotany: Cinchona, Quinine, and Malaria

Most folks these days who enjoy a gin and tonic on a warm summer day probably aren’t stricken or threatened with malaria, but the first partakers of this popular cocktail were. Their drinks, however, had a much larger helping of one particular ingredient, quinine. In the early 1600’s while exploring Peru, Jesuit missionaries from Spain were introduced to a tree, the bark of which could treat malaria. That tree was the cinchona tree. At that time malaria was a major issue in Europe, and so the Jesuits brought some cinchona bark back to Spain in hopes of saving some lives. The cinnamon-colored bark was administered by grinding it into a powder and serving it in sweetened water. This treatment became a big success and eventually spread throughout the continent. Exports of cinchona bark increased, much of which were coming from forests in the border region of Ecuador and Peru. Over time the cinchona bark (also called Jesuit’s bark and Peruvian bark) became less available, either due to overharvesting or because the Peruvians began to highly regulate its exportation. In order to fill the demand and ensure a steady supply, Dutch and British explorers established cinchona plantations in Southeast Asia.

Bark of Cinchona officinalis (photo credit: wikimedia commons)

Malaria is caused by protozoan parasites in the genus Plasmodium. Humans become infected with the parasites when they are bitten by infected mosquitos (Anopheles spp.). The parasites enter the bloodstream and liver and begin to reproduce. People with malaria experience flu-like symptoms and, if not treated quickly and properly, risk death. While early Europeans did not know it at the time, the cinchona bark treatment worked because it contained quinine, an antimalarial compound, which suppresses and destroys malarial parasites.

Quinine is an alkaloid (a class of nitrogen-containing organic compounds) that cinchona trees produce as a defense against insect herbivory. Many plants produce alkaloids for this reason, and these alkaloids, when discovered and isolated by humans, have proven to be quite useful. Caffeine, nicotine, morphine, and strychnine are all examples of alkaloids. Quinine was isolated from cinchona bark in the 1820’s and eventually produced synthetically in the 1940’s. It is still used today to treat malaria, although other antimalarial drugs are now favored due to greater effectiveness and fewer side effects. Today, products containing quinine are available for the treatment of leg cramps; however, the United States Food and Drug Administration has stated that they have not approved quinine for this use and advise consumers to avoid such products.

Cinchona is a genus of evergreen trees and shrubs in the family Rubiaceae (the coffee family) that includes around 23 species. It is native to the Andes of South America and mountains in the southern portion of Central America and often occurs in cloud forests, forests that are characterized by regular, canopy-level cloud cover. Cinchona flowers are tubular, pollinated largely by butterflies and hummingbirds, and come in white, pink, and purple. The fruits of Cinchona are dry, woody capsules containing small, flat, papery seeds that are wind dispersed. C. pubescens, C. calisaya, and C. officinalis are the main species that have been cultivated for quinine production.

The flowers of Cinchona pubescens (photo credit: wikimedia commons)

In the 19th century when Europeans were busy colonizing places like India and Africa, having a readily available source of cinchona bark was vital to their success. They may have had the guns and ammunition necessary for conquest, but even so, they would not have been able to withstand the plague of malaria parasites without regular doses of quinine. But quinine is bitter stuff. Served in sweetened soda water helped it go down. Add a ration of gin, even better. Imperialism was secured. Just something to think about the next time you’re mixing yourself a gin and tonic on a mid-September day.