The battle to keep as much of our own blood as possible may have a new, less toxic ally.
University of Mississippi researchers say that two chemicals occurring naturally in sweetgrass have been shown to ward off the ever annoying — and dangerous — mosquito, according to Smithsonian.
Native Americans — such as the Blackfeet — have used sweetgrass as a repellent by weaving ropes to hang around their necks, or just hanging them around their homes, according to the Post and Courier in Charleston, SC. It was also a popular perfume among the Blackfeet. The plant is native to Canada and New England, according to the USDA.
Now, Charles Cantrell of the USDA’s Natural Products Utilization Research Unit at the University of Mississippi says that his team has isolated the two compounds in the plant that mosquitoes hate: coumarin and phytol.
The team steam-distilled oil from sweetgrass and added them to vials of a substance similar to blood that they fed to skeeters, according to Smithsonian. They also compared it with other repellents, including DEET. The sweetgrass repelled mosquitoes as well as DEET in that test.
Coumarin is actually used in natural repellents. But the problem is that those don’t seem to last as long as DEET, Cantrell said.
“You see that the market is being flooded with natural products, essential oil-based insect repellents,” he told Smithsonian. “There are some that work, but there are a lot of them that may only work for 20 or 30 minutes. What we’re ideally looking for is something natural and nontoxic that’s just as effective as DEET, that will work as an effective repellent for 10 or 12 hours like DEET.”
