This web page is part of a web site that is no longer actively maintained by anybody at ANU SRES. It has been left on the web due to its apparent popularity (every time we've removed it, people have complained within 24 hours), but is presented AS IS - attempting to contact any individual named on the page is likely to fail, and the SRES webmaster doesn't want to hear about such failures or entertain any communication about updating of the page's contents. You have been warned.
Main Species: Cinchona officinalis
Other Species: C. calisaya, C. pubescens ( C. succirubra ), C. ledgeriana
Chemical Names: Quinine sulphate, Quinine bisulphate
Common Names: Cinchona, Quina, Quinquina, Quinine Bark, Peruvian Bark, Jesuit’s Bark
Quinine is a drug which is made from the bark of the Cinchona tree. A number of various other chemicals can also be synthesised from Cinchona, and these include cinchonine, cinchonidine and quinidine. Even before the 1600s, the Peruvian Indians used an infusion of Cinchona bark to treat fever, and soon it was recognised that Cinchona bark was also effective at treating and preventing malaria. At that point of time, no one actually knew that the potent ingredient was the alkaloid quinine. It was not until 1820 (200 years after the bark was introduced into Europe for the treatment of malaria) that quinine was isolated from the bark of the Cinchona tree. Aside from the treatment of malaria, quinine has also been used as a flavouring, and it provides the bitter taste in tonic water. In fact, "gin and tonic" was originally consumed in the past to prevent attacks of malaria (Upfal,1991).
Gradually however, natural quinine has been replaced by chemically synthesised drugs such as chloroquine and mefloquine, and quinine is now rarely used to treat malaria. However in recent years, with increasingly drug-resistant strains of malaria surfacing, quinine is once again showing promise for use in the treatment of malaria.
Cinchona & Its History
Cinchona is a genus of tropical evergreen trees and shrubs, with rather large laurel-like, entire, opposite leaves, and white or pink fragrant flowers arranged in clusters. It belongs to the family Rubiaceae, which also includes other members like Coffee and Gardenia. Not all species of Cinchona can be used to produce quinine, in fact, many contain virtually no quinine at all. The most important and useful species are Cinchona officinalis, C. calisaya and C. pubescens (also known as C. succirubra).
Cinchona was believed to have originated from the slopes of the Andes in South America. It is believed to have gotten its name from the Countess of Chinchon, wife of the Spanish Viceroy of Peru, who in 1638 fell desperately ill with malaria. Fortunately, she was cured using the ancient herbal remedy of "quinquina" bark, and in her honour, the tree was named Cinchona (Hobhouse,1987). After that incident however, the anti-malarial value of Cinchona became more widely recognised and the demand for it grew so much that supply could not keep up with demand. So valuable was the bark that at one point of time, the cost of the bark powder was often matched by its weight in gold. This prompted the wanton uncontrolled harvesting of the bark, which led to the severe decimation of the tree in its native habitat.
Interestingly enough, it was an illicit act that saved the Cinchona tree from extinction. Because Cinchona trees were so valuable, Peruvian officials strictly prohibited their export. However in the 1860s, some British and Dutch adventurers managed to smuggle a few seedlings out of the country, and they used them to set up large plantations in Java. Up until the Second World War, these plantations supplied almost 95% of the world's requirements of quinine. Ironically, seeds from these plantations were then later returned back Central America to establish plantations.
Malaria comes from the Italian words "mala" (bad) and "aria" (air). Worldwide, over 200 million people are infected with malaria, and at least one million die from the disease each year (Campbell,1993). Malaria is characterised by attacks of fever, chills, nausea and vomiting. Fever may be very high, over 40° C and is usually accompanied by severe headache, mild delirium and gastric pains. Malaria is caused by the Plasmodium parasite. There are different strains of malarial parasites, and these vary in their severity of attack. One of the most deadly strains is Plasmodium falciparum. The Plasmodium parasite has a highly specialised and intricate life cycle, which involves both sexual and asexual stages, and so requires different hosts for completion. The asexual stage occurs in humans, whilst the asexual stage occurs in mosquitoes (Campbell, 1993). When a mosquito bites an infected person, and then goes to feed on another uninfected person, it transmits the malarial parasite to the uninfected party. Malaria however, is only transmitted by the female Anopheles mosquito. (The male mosquito feeds on nectar and plant juices and is not involved in the transmission of malaria.) (Hobhouse, 1987). Quinine (and other drugs such as chloroquine) are effective in combating malaria because they are able to bind strongly to blood proteins, and form complexes which are toxic to the malarial parasite.
Properties & Uses
Quinine has many uses and applications. Some of the more common uses include:
In the past, Cinchona bark was prepared by grinding it down to a fine powder, and mixing it with water or wine. Currently however, quinine is generally taken in tablet form, but it can also be taken intravenously by injection. Nowadays, quinine is rarely employed for the treatment of malaria, except for a severe acute form known as falciparum malaria. It is however, commonly taken to relieve night-time leg cramps (Upfal, 1991).
When used in the suppression of malaria, the usual dosage range is 300
to 600mg of quinine daily. For the treatment of malaria, the dosage range
is 1.2 to 2.0g daily, in divided doses (Medicines Commission, 1980a; Medicines
Commission, 1980b). Excessive doses of quinine can lead to "cinchoism",
which is characterised by ringing in the ears, temporary deafness, blurred
vision, nausea and abdominal upset. In severe cases, it may even lead to
circulatory collaspe, kidney failure and coma (Upfal, 1991).
Campbell, N. (1993). Biology.
Benjamin/Cummings Publishing Co. Inc., California.
Hobhouse, H. (1987). Seeds of Change – Five plants that transformed mankind. Harper & Row, New York.
Medicines Commission (1980a). British Pharmacopoeia. Vol I. HMSO, University Press, Cambridge.
Medicines Commission (1980b). British Pharmacopoeia. Vol II. HMSO, University Press, Cambridge.
Upfal, J. (1991). The Australian Drug Guide. Schwartz Books, Melbourne.
Web References & Useful Links
Bradley, T. (1996). Introduction:
History of Plasmodium Parasites. http://www.wehi.edu.au/MalDB-www/intro.html
Bradley, T. (1996). Malaria and Drug Resistance. http://www-micro.msb.le.ac.uk/224/Bradley/Bradley.html
Desowitz, R. S. (1991). History of Malaria. http://www.idrc.ca/books/reports/1996/01-05e.html
Grieve, M. (1995). A Modern Herbal. http://www.botanical.com/botanical/mgmh/c/calisa08.html
Grieve, M. (1995). A Modern Herbal http://www.botanical.com/botanical/mgmh/p/perbar29.html
Healthlink (1998). Cinchona. http://www.healthlink.com.au/nat_lib/htm-data/htm-herb/bhp604.htm
King, S. R. (1992). Medicines that changed the world http://www.gene.com/AE/RC/Ethnobotany/page4.html
Raintree (1998). Quinine bark. http://www.rain-tree.com/quinine.htm
Shodex (nd). Cinchona alkaloids. http://www.sdk.co.jp/shodex/english/dc040216.htm
University of Hawaii. (1998). Cinchona pubescens. http://www.botany.hawaii.edu/faculty/cw_smith/cin_pub.htm
University of Wisconsin (nd). Rubiaceae. http://www.wisc.edu/botit/Systematics/family_index/Family_Pages/Family_R_S_T/Rubiaceae.html
Vanderbilt Medical Center (1998). Infectious diseases. http://www.mc.Vanderbilt.Edu/peds/pidl/infect/malaria.htm