North Carolina State University has obtained a patent for a chemical that could become a safer, more effective bug repellent.
In search of a mosquito repellant, scientists there were studying synthetic versions of a protein normally found in the gut of larval mosquitoes, where it makes the larvae stop eating at the appropriate time.
When team member R. Michael Roe looked at the molecular shape of the proteins, he noticed that their structure was similar to a compound in tomatoes that protects them from plant-eating insects.
"On a whim," Roe says, he tested the tomato compound to see if it repelled bugs other than those that attack tomatoes. When he applied the natural chemical to food offered to cockroaches, he found the pests "would rather starve than touch it."
When he put it on cloth in a mosquito cage, the insects flew the other way.