Health and Plant Biology
Harry Potter’s friend Neville Longbottom is smart to study Herbology, because plants are really useful: most of our medicines come from plants. At least until scientists figure out how to synthesize plant compounds in a lab. In the US, 40% of the medicines we use were originally found in plants; worldwide, where more cultures use traditional medicines, that number is 80%.
Some plant parts have useful medicinal properties as soon as you pick them off the plant—the over-the-counter medicines, so to speak. If you get sunburned or burned from a hot stove, you can pick an aloe leaf and rub it on the burn for some instant relief. If you have bad breath or an upset stomach, you can grab a mint leaf and chew on that. Of course you buy aloe lotion in a bottle too, if you aren’t so keen on picking it off the plant.
Other plants need a little more processing to release their medicinal properties, like medicines that need to be filled at a pharmacy. Taxol, an anti-cancer drug, was originally found in the bark of the yew tree (genus Taxus); now scientists can make it in a lab. The nasal decongestant pseudoephedrine, more commonly known as Sudafed, is modeled on the plants in the genus Ephedra. Interestingly enough, Ephedra plants were used by Mormons traveling west through the desert to make herbal tea because they didn’t want to drink caffeine. They didn’t know that it was full of ephedrine, which is a stimulant!
Digoxin, a drug used for congestive heart failure or irregular heart rhythm, was isolated from the common foxglove, Digitalis purpurea. Concoctions of foxglove were used to treat heart problems as early as the 1700s. In addition to being useful for heart issues, foxglove makes beautiful flowers! Digitalis purpurea and other members of its genus produce cardioactive glycosides (a steroid molecule attached to a sugar molecule) in their leaves; these compounds slow heart rate and increase the amount of blood pumped in each beat. This improves circulation and improves the edema associated with congestive heart failure.
Aspirin, one of the most popular drugs in use today, relieves fever and pain and owes its origins to a willow tree (Salix spp.). Many different cultures, including ancient Greeks and Native Americans, valued willow bark for its healing power. It took about a hundred years of experimentation, but finally in 1828, the active compound was isolated from willow bark. This isolated compound was called salicin, and is chemically related to salicylic acid. Salicylic acid became the new inexpensive treatment for many ailments, but chemists kept searching for another drug that was easier on the stomach. Salicylic acid is still used today for skin irritants such as acne, and its cousin acetylsalicylic acid was made into aspirin.
A few more plant remedies you may have heard of include gingko, ginseng, and ginger. If your parents are getting old and blaming their occasional lapses of memory on their age, have them try some Gingko biloba pills for their memory. These pills contain extracts from ginkgo leaves, which may increase attention span in older people. Another plant starting with a G, Ginseng, has long been used as an energy booster in Chinese culture. Lately ginseng has been making its way into American products, such as Pepsi Max. Speaking of soda, everyone knows ginger ale is good for an upset stomach. The ginger we eat and use for medicinal purposes is the rhizome (part of the shoot system that grows underground) of the ginger plant, Zingiber officinale.