Over millennia life (plants, microbes, fungi) developed toxins to protect them from predators. If humans can identify these toxins, they can use them to likewise protect themselves against diseases. Through serendipitous accident and random trial and error, over tens of thousands of years, indigenous peoples discovered and made use of some of these toxins. We should make use of this knowledge even though it is not certified by any randomized double-blind clinical trials performed by highly credentialed academics. Cassandra Quave, author of the essay quoted below, is working to do this, as is Berkeley professor Noah Whiteman, the author of Most Delicious Poison.
(p. C4) My team moved in unison to clip bits of plants, press them into sheets of paper and stuff them into large collection bags. Later, in my research lab at Emory University, we would test their chemical compounds against antibiotic-resistant pathogens. The possibility of developing new drugs from elements of nature such as our leaf clippings is important for everyone, but it’s personal for me; after losing my leg as a child, I nearly died as a result of postsurgical infection.
In recent decades, with the advance of high-tech methods for synthesizing molecules, the search for useful medical compounds from the natural world, especially plants, has faded. Fortunately, just as we’ve started to recognize the limits of artificial synthesis, even newer technology is now helping scientists like me to release more of nature’s medicinal secrets.
Plants have been the source of countless revolutionary medicines since the 19th century. Scientists derived aspirin from the willow tree, for instance, and morphine from opium poppies. They found quinine, the first treatment for malaria, in the bark of the Amazon’s fever tree (and more than a century later, scientists in China found that artemisinin from sweet wormwood was also a powerful anti-malarial agent). Many groundbreaking cancer drugs also came from plants—Taxol from the Pacific yew tree, vincristine from the Madagascar periwinkle.
Microbes found in soil and fungi launched a golden era of advances in antibiotics, starting with the discovery of penicillin in a mold in 1928. By the peak in the 1950s, scientists were isolating a wide range of antimicrobial compounds from microbes found in nature. But such work ended all too soon, as scientists stopped discovering effective new compounds.
Many of the drugs originally drawn from nature are now synthesized in pharmaceutical factories, using the blueprint of their chemical structures. Natural products (that is, chemicals genetically encoded and produced by living organisms) account for more than 60% of the pharmaceuticals that we possess.
Over the past 30 years, however, the focus on nature waned as scientists instead built large chemical libraries filled with tens of thousands of lab-made molecules. One hope was that the next antibiotic breakthrough would emerge from making and testing enough of these synthetic compounds. But that effort has fallen flat: Though other medicines have been developed in the lab, no new registered classes of antibiotics have been discovered since the 1980s.
For the full essay see:
(Note: the online version of the essay has the same date and title as the print version.)
Quave’s essay is adapted from her book:
Quave, Cassandra Leah. The Plant Hunter: A Scientist’s Quest for Nature’s Next Medicines. New York: Viking, 2021.
The Noah Whiteman book I praise in my introductory comments is:
Whiteman, Noah. Most Delicious Poison: The Story of Nature’s Toxins―from Spices to Vices. New York: Little, Brown Spark, 2023.