Cinchona

Cinchona /sɪŋˈkoʊnə/ is a genus of flowering plants in the family Rubiaceae containing at least 23 species of trees and shrubs. They are native to the tropical Andean forests of western South America. A few species are reportedly naturalized in Central America, Jamaica, French Polynesia, Sulawesi, Saint Helena in the South Atlantic, and São Tomé and Príncipe off the coast of tropical Africa. Several species were sought after for their medicinal value and cultivated in India and Java where they also formed hybrids. The barks of several species yield quinine and other alkaloids that were the only effective treatments against malaria during the height of colonialism which made them of great economic and political importance. The synthesis of quinine in 1944, an increase in resistant forms of malaria, and alternate therapies ended the large-scale economic interest in their cultivation. Academic interest continues as cinchona alkaloids show promise in treating falciparum malaria which has evolved resistance to synthetic drugs. Carl Linnaeus named the genus in 1742 based on a claim, first recorded by the Italian physician Sebastiano Bado in 1663, that the plant had cured the wife of the Luis Jerónimo de Cabrera, 4th Count of Chinchón, Count of Chinchón, a viceroy in Lima. While the veracity of the claims and the details are highly debated leaving it best treated as a legend, the curative properties were known even earlier. The history of the plants, their identification, extracts, and the cures are disputed. Suggestions that the plant went by the native name of Quina Quina which yielded Quina bark have been questioned. Other fever cures from South America were known as Jesuit's Bark and Jesuit's Powder in Europe earlier but although they have been traced to Cinchona, there is evidence of materials being derived from other species such as Myroxylon. The species that Linnaeus used to describe the genus was Cinchona officinalis which is found only in a small region in Ecuador and specimens of which were obtained by Charles Marie de La Condamine around 1735. This species is of little medicinal significance. In the course of the quest for species yielding effective remedies, numerous species were described, some now considered invalid or synonyms of others. Linnaeus used the Italian spelling used by Bado but the name Chinchón (pronounced in Spanish) led to Clements Markham and others proposing a correction of the spelling to Chinchona and some prefer the pronunciation /tʃɪnˈtʃoʊnə/ for the common name of the plant. The national tree of Peru is in the genus Cinchona. Cinchona plants belong to the family Rubiaceae and are large shrubs or small trees with evergreen foliage, growing 5–15 m (16–49 ft) in height. The leaves are opposite, rounded to lanceolate and 10–40 cm long. The flowers are white, pink or red, produced in terminal panicles. The fruit is a small capsule containing numerous seeds. A key character of the genus is that the flowers have marginally hairy corolla lobes. The tribe Cinchoneae includes other genera Cinchonopsis, Jossia, Ladenbergia, Remijia, Stilpnophyllum, and Ciliosemina. In South America, the species had geographically distinct distributions. The introduction of several species into cultivation in the same areas in India and Java, respectively, by the English and Dutch East India Companies led to the formation of hybrids. Linnaeus described the genus based on the species Cinchona officinalis. Nearly 300 species have been described and named in the genus but a revision of the genus in 1998 identified 23 distinct species. The febrifugal properties of bark from trees now known to be in the genus Cinchona were used by many South American cultures but malaria was an Old World disease that was introduced into the Americas by Europeans only after 1492. The origins and claims to the use of febrifugal barks and powders in Europe, especially those used against malaria, were disputed even in the 17th century. Jesuits played a key role in the transfer of remedies from the New World. The traditional story, first recorded by Sebastiano Bado in 1663, is that the wife of the fourth Count of Chinchon fell ill in Lima with a tertian fever. A Spanish governor advised a traditional remedy which was tried, resulting in a miraculous and rapid cure. The Countess then ordered a large quantity of the bark and took it back to Europe. Bado claimed to have received this information from an Italian named Antonius Bollus who was a merchant in Peru. Clements Markham identified the Countess as Ana de Osorio but this was shown to be incorrect by Haggis. Ana de Osorio married the Count in August 1621 and died in 1625, even before the Count was appointed Viceroy of Peru in 1628. It was his second wife, Francisca Henriques de Ribera, who accompanied him to Peru. Haggis further examined the diaries of the Count of Chinchon and found no mention of the Countess suffering from fever although the Count himself had many malarial attacks. On account of numerous other discrepancies this is best treated as a legend. Quina bark was mentioned by Fray Antonio de La Calancha in 1638 as coming from a tree in Loja (Loxa). He noted that bark powder weighing about two coins was cast into water and drunk to cure fevers and 'tertians'. Jesuit Father Bernabé Cobo (1582–1657) also wrote on the 'fever tree' in 1653. The legend was popularized in English literature by Markham in his writings and in 1874 he also published a 'plea for the correct spelling of the genus Chinchona'. A Spanish physician, Juan Fragoso wrote of bark powder from an unknown tree in 1600 that was used for treating various ills. Nicolas Monardes also wrote of a New World bark powder used in Spain in 1574. Both identify the sources as trees that do not bear fruit and having heart-shaped leaves and it has been suggested that these references could be to Cinchona species. The name Quina-Quina or Quinquina was suggested as an old name for Cinchona used in Europe and based on the native name used by the Quechua people. Italian sources spelt Quina as Cina which was a source of confusion with Smilax from China. Haggis argued that Qina and Jesuit's bark actually referred to Myroxylon peruiferum or Peruvian balsam and that this was an item of importance in Spanish trade in the 1500s. Over time, the bark of the Myroxylon was adulterated with the similar looking bark of what we now know as Cinchona. Gradually the adulterant became the main product that was the key therapeutic ingredient used in malarial therapy. The bark was included as Cortex Peruanus in the London Pharmacopoeia in 1677. The 'fever tree' was finally described carefully by the astronomer Charles Marie de la Condamine who visited Quito in 1735 on a quest to measure an arc of the meridian. The species he described, Cinchona officinalis, was however found to be of little therapeutic value. The first living plants seen in Europe were C. calisaya plants grown at the Jardin des Plantes from seeds collected by Hugh Algernon Weddell from Bolivia in 1846. José Celestino Mutis, physician to the Viceroy of Nueva Granada, Pedro Messia de la Cerda gathered information on cinchona in Colombia from 1760 and wrote a manuscript El Arcano de la Quina (1793) with illustrations. He proposed a Spanish expedition to search for plants of commercial value which was approved in 1783 and was continued after his death in 1808 by his nephew Sinforoso Mutis. As demand for the bark increased the trees in the forests began to be destroyed. To maintain their monopoly on cinchona bark, Peru and surrounding countries began outlawing the export of cinchona seeds and saplings beginning in the early 19th century. The Colonial European powers considered growing the plant in other tropical parts. The French mission of 1743, of which de la Condamine was member, lost their plants when a wave took them off their ship. The Dutch sent Justus Hasskarl who brought plants that were then cultivated in Java from 1854. The English explorer Clements Markham went to collect plants that were introduced in Sri Lanka and the Nilgiris of southern India in 1860. The main species introduced were Cinchona succirubra or red bark, as its sap turned red on contact with air, and Cinchona calisaya. The alkaloids quinine and cinchonine were extracted by Pelletier and Caventou in 1820. Later two more key alkaloids, quinidine and cinchonidine were identified and it became a routine in quinology to examine the contents of these components in assays. The yields of quinine in the cultivated trees were low and it took a while to develop sustainable methods to extract bark. In the meantime Charles Ledger and his native assistant Manuel collected another species from Bolivia. Manuel was caught and beaten by Bolivian officials leading to his death but Ledger obtained seeds of high quality which were offered to the British who were uninterested, leading to the rest being sold to the Dutch. The Dutch saw its value and multiplied the stock. The species later named as Cinchona ledgeriana had a yield of 8 to 13 percent quinine in bark grown in Dutch Indonesia which effectively out-competed the British Indian production. It was only later that the English saw the value and sought to obtain the seeds of C. ledgeriana from the Dutch. During World War II, the Japanese conquered Java and the United States lost access to the cinchona plantations that supplied war-critical quinine medication. Botanical expeditions – called Cinchona Missions – were launched in 1942-1944 to explore promising areas of South America in an effort to locate cinchona species that contained quinine and could be harvested for quinine production. While ultimately successful in their primary aim, these expeditions also identified new species of plants and created a new chapter in international relations between the United States and other nations in the Americas.