Visit Your Local PBS Station PBS Home PBS Home Programs A-Z TV Schedules Watch Video Donate Shop PBS Search PBS
Forgotten Genius

Nature's Pharmacy

Plants, animals, and fungi each contain thousands of chemical compounds, which they use in everything from reproduction to defense against predators and disease. Scientists have long harnessed such natural chemicals to fight human illnesses, often synthesizing them (artificially creating them in the lab) and developing them into drugs. In this slide show, take a look at a few species that have offered up cures and salves for a number of afflictions.—Claudine Ko


Engine
Enlarge this image

 

Cinchona tree
For centuries, Native Peruvians used dried bark from the South American cinchona tree for various medicinal purposes, including as a muscle relaxant and fever reducer. In the 1600s, Europeans began treating malaria patients with the bark. Finally, in 1820, French chemists Pierre Joseph Pelletier and Joseph Caventou extracted quinine from the bark, which became the first pure chemical isolated from a plant and utilized against a specific disease.



Prop
Enlarge this image
 

Streptomyces bacteria
Streptomycetes (genus Streptomyces) are soil bacteria essential to the decomposition of organic matter. Highly prolific synthesizers of antibiotics, they supply over half of the world's current varieties, including important cancer-fighting drugs such as Actinomycin-D and Bleomycin.



Wing Structure
Enlarge this image

 

Penicillium mold
Penicillium notatum is a blue-green mold commonly found on spoiled bread and fruit, particularly rotten tangerines. Ever since Scottish chemist Alexander Fleming accidentally discovered the mold's antibacterial properties in 1928, chemists have used it to produce many varieties of penicillin, antibiotics that continue to be immensely valuable in treating bacterial infections.



Landing Gear
Enlarge this image

 

Cone snail
Found in tropical seas, carnivorous mollusks known as cone snails sport venomous harpoons that can instantly paralyze small fish and other prey. The snails' venom contains hundreds of compounds, some of which chemists have used to create highly powerful, nonaddictive painkillers such as Prialt and Ziconotide.



Tail Assembly
Enlarge this image
 

Pacific yew
In 1958, the National Cancer Institute commissioned a study of over 30,000 plant species in hopes of discovering cancer-fighting compounds. Scientists found one in the bark of the Pacific yew, a conifer native to the Pacific Northwest. Yet it took extractions from six Pacific yews to yield enough of the anti-tumor compound paclitaxel for a single patient. Eventually, researchers learned how to convert a compound from the tree's needles into paclitaxel, which doctors now use to treat lung, breast, and other cancers.



Cruciform
Enlarge this image
 

Opium poppy
The opium poppy is harvested by scoring the shells of its ripening pods. This releases a milky latex that dries into a dark resin. The secretion contains alkaloids, or basic nitrogen-containing compounds, many of which have physiological effects. The most important alkaloid in opium is morphine, a highly addictive but very powerful painkiller.



Bamboo Frame
Enlarge this image

 

Foxglove
In the late 18th century, scientists discovered that extracts from the leaves of foxglove, a biennial herb with violet or white flowers that is also known as digitalis, could help treat heart conditions. Today, the isolation of pure digitalis components such as digoxin allows reliable treatment of various cardiac conditions, including congestive heart failure, atrial fibrillation, and atrial flutter.



Tail Skid
Enlarge this image

 

Soybean
In 1939, after a fortuitous accident, Percy Julian isolated the steroid stigmasterol from soybean oil. From stigmasterol, Julian figured out how to make other steroids, including progesterone, estrogen, testosterone, and cortisone. This made many crucial drugs more accessible for patients suffering from diseases such as arthritis and hormonal deficiencies.



Tail Skid
Enlarge this image

 

Mexican wild yam
In 1936, Japanese researchers discovered the compound diosgenin in the Mexican wild yam. Like stigmasterol, diosgenin provides a starting material for synthesizing many steroids, such as estrogen, testosterone, and progesterone, as well as drugs such as the birth-control pill. Mexican yams are cheap and plentiful, and just two to three of their roots can yield up to a pound of diosgenin. In 1944, chemist Russell Marker and two partners formed a company called Syntex to make hormones from the yam, helping to launch the artificial sex-hormone industry.



Interactives

We recommend you visit the interactive version. The text to the left is provided for printing purposes.

Forgotten Genius Home | Send Feedback | Image Credits | Support NOVA


© | Created January 2007

Support provided by

For new content
visit the redesigned
NOVA site