Medicinal Plants Used During the US Civil War Are Surprisingly Good at Fighting Bacteria

By George Dvorsky on at

With conventional medicines in short supply during the US Civil War, the Confederacy turned to plant-based alternatives in desperation. New research suggests some of these remedies were actually quite good at fighting off infections—a finding that could lead to effective new drugs.

Three plant-based topical remedies listed in a Confederate Civil War field guide have antiseptic qualities, according to new research published last week in Scientific Reports. The antibacterial compounds were derived from white oak, tulip poplar, and devil’s walking stick.

The active ingredients of the remedies are still not known, but the finding suggests these plant-based medicines may have actually saved some lives during the war, and perhaps even preventing the amputation of infected limbs.

“As we look toward a future where many of our current antibiotics may no longer work... I think it’s important to have alternative strategies in development to fill that gap.”

The new research also highlights the value of investigating old-timey therapies, which could be reconstituted into modern medicines.

“As we look toward a future where many of our current antibiotics may no longer work with the efficacy to which we have become accustomed, I think it’s important to have alternative strategies in development to fill that gap,” Cassandra Quave, senior author of the new paper and an ethnobotanist at Emory University, told Gizmodo in an email. “The significance of the study is that it offers another proof-of-concept case that some of our solutions for the post-antibiotic era may be found in the medical traditions of the pre-antibiotic era.”

Quave said it’s important to look back on historical data relating to the use of medicinal plants, particularly as we search for solutions to emerging medical challenges.

“Luckily, today we have advanced scientific methodologies and instrumentation that enables a deeper look at these historic remedies,” said Quave.

During the Civil War (1861-1865), Union forces suffocated the South with a blockade, dramatically limiting the amount of goods available to the Confederacy—including its access to conventional medicines. With soaring infection rates among wounded soldiers, Confederate Surgeon General Samuel Moore commissioned Francis Porcher, a botanist and surgeon from the state of South Carolina, to compile a book of medicinal plants found in the Southern states. Porcher was asked to include folk remedies used by white Southerners, as well as those used by enslaved Africans and indigenous peoples.

An 1863 copy of “Resources of the Southern Fields and Forests,” by Francis Porcher. (Image: Stephen Nowland, Emory University)

The book, titled “Resources of the Southern Fields and Forests,” was published in 1863. The compendium was amazingly thorough, and included, for example, nearly 40 plant species used to treat gangrene and other infections. Equipped with this book, Moore sketched out a condensed version called “Standard supply table of the indigenous remedies for field service and the sick in general hospitals,” which neatly described the way in which the field guide was used by the South during the latter stages of the Civil War.

This guide likely came in handy. As the war raged on, and as conventional medicines became scarce, disease began to exert a terrible toll on soldiers. The majority of casualties and deaths in the Civil War, as the American Battle Trust points out, were the result of non-combat-related diseases. Germ theory was still in its nascent stage of development, yet doctors understood the importance of using antiseptics to stave of infections even if it wasn’t immediately obvious as to why.

To assess the antimicrobial potential of these Civil War-era remedies, Quave and her colleagues selected three specific plant-based medicines to test in the lab, specifically those derived from the white oak and tulip poplar (both trees) and devil’s walking stick (a thorny, woody shrub). All three were used during the war as a topical, or external, rinse for wounds. Using Porter’s book as their guide, the researchers selected specific extracts from the bark, leaves, galls, and other parts of the plants. These compounds were then tested against three species of drug-resistant bacteria associated with wounds, namely Acinetobacter baumannii, Staphylococcus aureus, and Klebsiella pneumoniae.

“We found that they worked against a number of bacteria that are commonly implicated in [wartime] wounds—including drug-resistant strains,” said Quave. “While some exhibited classic antibiotic activity—such as slowing down the growth or killing the bacteria—others acted by blocking the bacteria’s ability to stick to surfaces (important to wounds) or by blocking bacterial communication responsible for the production of toxins that destroy tissues.”

When asked if doctors would ever want to treat an infection solely with one of these remedies, Quave said it would depend on the context.

“I don’t believe these would be effective as an oral medication to treat a systemic infection, but they could be potentially useful in wound care—perhaps formulated as a wound rinse, hydrogel, or medicated bandage,” she said.

“This new scientific research confirms that folk medicine used in the Civil War actually did fight bacteria and prevent infection,” Joan E. Cashin, a historian at the Ohio State University and author of War Stuff: The Struggle For Human And Environmental Resources In The American Civil War, wrote in an email to Gizmodo. “These staggering results prove yet again that truth—and history—is stranger than fiction,” said Cashin, who wasn’t involved in the new study.

Looking ahead, Quave would like to determine which compounds are responsible for the specific antibacterial activities observed in the study, and to test formulations of the most promising extracts in wounds infected with antibiotic resistant bacteria. Ultimately, Quave would like to see these discoveries translated to actual medicines.

“Perhaps the best implementation will be as a topical antimicrobial medical device—like a hydrogel, wound rinse, or medicated bandage,” she said.

Featured image: Stephen Nowland, Emory University