Grapefruit: Not Just for Breakfast
Written by UMass Amherst senior biology major, Cayla McGonigle
Vector-borne diseases like Lyme disease and Rocky Mountain spotted fever are constantly being studied in hopes of improving repellant options. To that end, PhD student Eric Siegel led research on a surprising hero: the grapefruit. The paper, “Ixodes scapularis is the Most Susceptible of the Three Canonical Human-Biting Tick Species of North America to Repellent and Acaricidal Effects of the Natural Sesquiterpene, (+)-Nootkatone,” highlights his work. The major vector for Lyme disease in the eastern United States is Ixodes scapularis (the blacklegged tick), and the compound found in grapefruit, nootkatone, may be a game changer for controlling these ticks.
When testing nootkatone against a variety of tick species including blacklegged, lone star, and American dog ticks, blacklegged ticks were the most susceptible, meaning nootkatone worked best to repel them. Even low levels of nootkatone repelled the blacklegged ticks, and after the exposure period this species had significant mortality. Nootkatone is naturally occurring and found in plants and already known as a biopesticide by the EPA, which makes it safer to use around humans, pets, and the environment and it is designated GRAS (generally regarded as safe) by the Food and Drug Administration. This research is a big step toward sustainable, safe tick repellents. Nootkatone is also known to kill ticks, and research in that realm is ongoing.
