2020/02/26 Beauty in botany

An art exhibition at The New York Botanical Garden highlights our modern reliance on plants and the need to conserve them

Mention "medicinal plants" and you're likely to conjure up images of folk doctors wielding salves and tinctures, practicing something more akin to witchcraft than science. But surveying cancer treatments alone, it's astounding how many of the compounds we use today were initially discovered in plants. The widely-used drugs vinblastine and vincristine, anti-mitotic compounds used to treat leukemia and other cancers, were isolated from the Madagascar periwinkle (Catharanthus roseus) in the 1950s. The breast, ovarian, and lung cancer treatment paclitaxel, another mitosis inhibitor, was found in the bark of the Pacific yew tree (Taxus brevifolia) in 1967. Etoposide phosphate, an anti-tumor agent that disrupts proper DNA unwinding, was derived from podophyllotoxin which is produced by the mayapple (Podophyllum peltatum). And that's just the start of a long list.

Cotton, Gossypium herbaceum
© 2010 Esther Klahne, watercolor on paper

Image: Courtesy of The NYBG
"The world has perhaps [more than] 200,000 species of higher plants and fewer than one-half of one-percent have been totally and thoroughly investigated for their chemical composition and medical application," says ethnobotanist Michael Balick, the Vice President for Botanical Science at The New York Botanical Garden. After all, it would take a "phenomenal" effort to perform all those screens and assays, but the payoff could be huge, according to Balick. "Out of that one-half of one-percent [of plants that have been screened] has come a lot of our medicine," he says.

Balick helped select the works that appear in "Green Currency: Plants in the Economy," a new exhibition of botanical art at The New York Botanical Garden that opens on April 20. The exhibition features breathtaking and realistic studies of the plants that people rely on day-to-day, highlighting some obscure uses for commonplace plants.

Marijuana, Cannabis sativa
© 2010 Dorothy DePaulo, colored pencil on film

Image: Courtesy of The NYBG
"Looking at an exhibit of plants that impact all facets of our lives from food, to medicine, to recreation, to fibers really drives the message home that plants and the environments that they come from are still very important parts of our lives," he says. "And thus conserving them, appreciating them, and appreciating the habitats where they're found is important."

Balick has dedicated his life to collecting and studying medicinal plants around the world to generate resources for communities that don't have regular access to healthcare. While working on the Pacific island of Pohnpei, Balick noticed that patients with cholera and diarrheal infections were out of luck as soon as doctors ran out of medicine, while the plant that had been used traditionally as a treatment was growing all around the clinic. "We are trying to integrate traditional therapies [whose effectiveness is supported by] scientific evidence with more modern pharmaceutical therapies as a way of having these islands be more self-sufficient and lowering the cost of healthcare," he says. In August 2010, Balick and his colleagues published the Pohnpei Primary Health Care Manual, a reference book providing guidelines for healthcare using traditional plant-based medicines in the Pacific region.

Heirloom Tomato, Solanum lycopersicum
© 2009 Asuka Hishiki, watercolor on paper

Image: Courtesy of The NYBG
"Green Currency" showcases the plants that humans rely on for many reasons -- medicine, food, furniture, fiber and fun -- with the aim of pointing out our dependence on them and the need for conservation and sustainability. "We're hoping to bring attention to this theme through all of these dozens of artists who have contributed their works, sharing the beauty of plants and their importance in contemporary life," Balick says.

The exhibit includes racy plants, such as hops and marijuana, but many of the specimens are fairly mundane -- an eggplant, a ginger root, an ear of corn, or an onion. "I hadn't really thought about an onion as a piece of art," Balick says. "It's given me a whole different perspective of the beauty of an onion."

Read more: Beauty in botany - The Scientist - Magazine of the Life Sciences