As scientific director of the Institute for the Preservation of Medical Traditions at the Smithsonian, Alain Touwaide is compiling a database of medicinal plants of antiquity. Proficient in 12 languages, he has a PhD in classics from the Catholic University of Louvain (UCL) in Belgium. New Scientist asked him about his mission to unearth lost medicinal knowledge from ancient manuscripts.
What would the ancient Greek physician Hippocrates have used to treat, say, a bad headache?
A cataplasm—or poultice—made of iris mixed with vinegar and rose perfume. And for a chronic headache, squirting cucumber.
What if he had a stomach ailment?
Dates, a hen's broth and cultivated lettuce.
What is the most memorable remedy you've come across?
Spiders' webs. Amazingly, I found spiders' webs and many other materia medica mentioned in the ancient literature when my wife and I visited the shop of a traditional healer in the Turkish city of Konya. We felt as if we had traveled back in time 2,000 years.
How do you find out about these remedies?
I search for them in ancient manuscripts from libraries all over the world—the British Library in London, the Vatican Library or in the many collections housed in the monasteries on the Athos peninsula in Greece. It's what I call my fieldwork. But many manuscripts are also in smaller libraries scattered all through Europe. I also follow the antiquarian book market.
I specialize in the ancient medico-pharmaceutical literature based on Mediterranean flora, and I study the texts in their original language—Greek, Latin, Arabic.
In the hunt for new plant-based medicines, broccoli is a popular target. Has it been used as a medicine in the past?
We have discovered a wealth of data on broccoli in the ancient literature. Originally it was mainly used to treat gynecological disorders. Then from the 3rd century B.C. it was also used for digestive troubles, tetanus and possibly dropsy. In the 1st century A.D., skin infections were the most important illnesses treated with broccoli, followed by troubles of the digestive system.
The ancient Roman Cato felt all Roman citizens should grow broccoli in their orchard to use as a sort of all-purpose medicine, and the Greek physician Galen prescribed broccoli to treat a medical condition that was most probably colon cancer.
Are there other plants mentioned in classical texts that have potential as new medicines?
Walnut, and the herbs black horehound and white horehound. These plants are credited with a disinfectant and anti-inflammatory action in the ancient literature. They appear to be active against the bacterium Staphylococcus aureus, even drug-resistant strains. And red raspberry (Rubus idaeus) is recommended for treating inflammation in ancient literature. In modern-day tests it appears to be active against superficial skin inflammation.
Have any new medicines come out from studying ancient ones?
The best example is artemisin—the malaria treatment derived from the Artemisia plant. Malaria plagued the ancient world, and we have found more than 70 agents to treat it in the Greek medical literature of the classical period, from the 5th century B.C. to 3rd century A.D.—including Artemisia. It was identified quite recently by Chinese pharmacologists on the basis of their ancient literature.
Currently, we have quite a range of plants on our databases that should be tested for the treatment of malaria.