Looking for Medicine in All the Right Places
In today’s world of synthetic pharmaceuticals, scientists and laypeople alike have lost this connection to the natural world. But by ignoring the potential of medicinal plants, we are losing out on the opportunity to discover new life-saving medicines needed in the fight against the greatest medical challenge of this century: the rise of the post-antibiotic era. Antibiotic-resistant microbes plague us all. Each year, 700,000 people die due to these untreatable infections; by 2050, 10 million annual deaths are expected unless we act now. No one understands this better than Dr. Cassandra Quave, whose groundbreaking research as a leading medical ethnobotanist — someone who identifies and studies plants that may be able to treat antimicrobial resistance and other threatening illnesses — is helping to provide clues for the next generation of advanced medicines.
In a wet grassy pasture bordering the swamplands of Florida, I stood with my team of six students, surveying what would be our work site for the morning. We’d all woken up early and driven the twenty miles into the countryside as dawn began to throw its rays over the swamp. This was the latest of many expeditions I had lead for the students working out of my lab at Emory University. Our mission: find plants.The field was filled with invasive weeds — explosions of spiny soda apple with their hard, yellow fruits and prickly leaves, and bushes of feathery dog fennel that waved in the wind as if to greet us. Fifteen feet away, the green field turned to black muck, where a long stand of cypress trees, their knobby knees poking out from the water, stood as wizened sentries to the swamp. I stared at the scene a moment longer, wiping my brow. I hadn’t even started to work and I was sweating like a dog in this April humidity.
As a professor and the herbarium curator at Emory, I’m dedicated to the discovery of new medicines derived from plants. My students and I were out in this swampland to collect some one hundred different plant species over the next two weeks; then we’d bring them all back to my lab to study. We’d spent the previous three months preparing for this trip, combing through historical records of Native American plant use, creating a customized field guide of the medicinal plants and their applications complete with identifying photos, and planning all of the logistical elements required of an intensive scientific expedition.
Finally, we were ready to go.
“Wait!” I said. “Let’s change into tall boots.”
Never underestimate Florida muck.
The students pulled on mud boots while I sat on our truck’s tailgate. It would take me a little longer than them to get ready. Born with multiple congenital defects of my skeletal system, I’ve been immersed in medicine and science, in one form or another, right from the start. I’ve been subjected to scores of surgeries, beginning with an amputation just below my knee at the age of three, which have given me the ability to walk, using various models of prosthetic legs. Today, I wore my most stripped-down version — a metal pylon connecting the stump below my knee to a rubber foot shell. The prosthetic ankle didn’t bend, making it almost impossible for me to put on a normal boot. Luckily, my handy husband, Marco, installed a zipper down the back of this particular boot, so slipping it on was relatively simple. Once I was booted up, I checked the gear strapped to my army utility belt — bowie knife, a set of pruning clippers called secateurs, a Japanese hori-hori digging knife, a hand radio, and a .357 Smith & Wesson pistol.
We weren’t there to hunt wildlife, but I knew better than to trespass on gator territory without a form of defense. My pistol was loaded with hollow points, the safety on. Few people are well acquainted with real Florida ecosystems — the inland swamps and wetlands where a picnic by the water can end with you becoming the meal — but this wild, dangerous, untouched part of the state was where I grew up.
Each student was equipped with hand radios, clippers, and shovels. They spread out in pairs along the swamp’s edge, entering from different angles like a big pack of wolves hunting down prey. I sent two of them off opposite our group toward the creek to wade through the shrubbery and tall grasses in search of the elusive blackberry bush, while the rest of us entered the swamp head-on.
Kim, an energetic young woman who’d been with the lab for a year now, was the first student to call me over. I used my hiking stick to help me slog through the rough terrain, my boots slurping and squelching in the muck. She pointed to a small herb, about a foot tall, with clusters of dainty white flowers along its distal stalk. “Hello, gorgeous,” I said, touching it with my fingertips. I flipped through the pages of our field guide to confirm my hunch.
“Great find!” I said with reverence. “It’s from the Saururaceae family — it only grows in this kind of swampy habitat.” Its name is lizard’s tail (Saururus cernuus) and its roots had been used by the Cherokee and Choctaw people to make a poultice to apply to wounds; the Seminole used the whole plant to treat spider bites.
With our day’s first find confirmed, the students around me knew the drill. I clipped a specimen to be included in our expanding herbarium collection, while Kim and the others began carefully collecting a bucketload of the plant so we would have enough for extraction back in the lab. We pressed the individual clippings into sheets of newspaper labeled with their name, collection number, date, and location. Layers of cardboard and blotter paper were then added and stacked inside of a wooden-slatted plant press, which could be squeezed tightly together for the drying process to yield flat samples for long-term storage in the Emory Herbarium.
We continued this way — search, identify, collect — like some crazy cross between a platoon on a reconnaissance mission, off-the-grid campers collecting foodstuffs, and shoppers wandering the aisles of the world’s biggest and wildest Walmart. After an hour or so of strenuous work and more than a few sought-after plants located, I heard Josh on the radio triumphantly announce those two precious words I had been longing for: “Found it.” A jolt of joy shot through me. They had found the blackberry bush.
At the heart of science is the unalloyed joy of discovery. Every plant I seek out during fieldwork is like buried or long-lost treasure I’m on the hunt for, but this type of blackberry bush, known as a Rubus species, was the mother lode for this journey. I was so eager to see it, I nearly slipped in the muck — clomping and stomping — as I made my way to Josh. With well over three hundred different species scattered across the earth, Rubus has been used for centuries by Native peoples to treat diarrhea, sexually transmitted diseases, and skin infections. I was hoping to add some North American species to my roster of studied plants, because I’d already examined one species native to Italy that demonstrated extremely promising antibacterial properties.[i] It was a biofilm inhibitor, which means it blocks bacteria’s ability to stick to surfaces, making the bacteria more vulnerable to attack from antibiotics or the immune system. If we collected even more Rubus species, we could learn more about their potential utility against one of the most troubling developments since the discovery of antibiotics: antibiotic-resistant bacteria. This is my enemy, my archnemesis, and what I do is develop weapons to fight what may become the next major war in humanity’s struggle to survive.
Excerpted from The Plant Hunter by permission of Viking Books. Download Buzz Books 2021 to read more of this title, as well as dozens of other excerpts of forthcoming books.
