UC Riverside scientists find new potential pesticide in plants

Researchers at UC Riverside recently helped identify a naturally occurring compound that is deadly to bugs but harmless to people and other animals.

It could lead to new forms of environmentally friendly pesticides, said UC Riverside researcher Alexander Raikhel.

The compound is found in plants, and it disrupts something in insects called juvenile hormone. This hormone is found across many types of bugs and affects development, reproduction and other vital functions.

"It is a very attractive target because it exists only in insects and their relative groups," Raihkel said.

Mess with this hormone, and you can kill young bugs and sterilize adult ones.

That could be a boon for places trying to eliminate hazardous pests like mosquitos that can spread serious diseases like West Nile Virus and Yellow Fever.

The researchers had a hunch that some plants might have a compound that disrupts juvenile hormones as a natural defense.

After examining 1,651 plant species, the team found five naturally occurring molecules known as juvenile hormone antagonists, or JHANs. These proved to be very effective at disrupting the hormone and killing larvae. 

"They're killed quite quickly," he said.

Unlike other pesticides, which can be toxic to humans, animals and many other creatures besides insects, JHANs only harm bugs.

However, Raikhel says more testing needs to be done to see whether they can make any new pesticide from these compound that would only harm specific problem insects like mosquitos.

"We don't want to have something to kill all insects, we want [something] very specific, but that's down the road," he said.

This research appeared in the journal Proceedings of the National Academy of Sciences and was done in conjunction with a team from Korea led by Sang Woon Shin at Seoul National University.