UC Davis

Nature uses the hydrolysis of enol esters to form certain ketone and aldehyde signals for inter-organism communication. The kinetics of this semiochemical attenuation strategy was explored at the laboratory-scale in the context of developing integrated pest management (IPM) tools, such as insect pheromone lures. Emission of the ketone hydrolysate heptan-2-one (1) into an airstream was quantified following the addition of enol ester hept-1-en-2-yl acetate (2) to an aqueous sugar solution held at near-constant temperature and humidity. Results demonstrate formulation utility, as emission of 1 from sugar solutions fortified with 2 was significantly attenuated, relative to those fortified with 1, during triplicate trials conducted over the environmentally relevant temperature range of 18 to 27 °C. The half-life (t1/2) of 1 emitted from 2- (and 1)-fortified sugar solutions decreased with increasing T. Results indicate attenuation of a ketone and/or aldehyde can be extended via the incorporation of more water-soluble precursors via strategic structural modification of the acid coupling agent used to synthesize the enol ester. Collectively, these findings merit further exploration of this formulation strategy for the slow release of highly volatile, intrinsically reactive ketone and aldehyde semiochemicals