Prooxidant effects of phenolic acids on the generalist herbivore Helicoverpa zea (Lepidoptera: Noctuidae): Potential mode of action for phenolic compounds in plant anti-herbivore chemistry

The ability of a series of phenolic acids to induce oxidative stress in Helicoverpa zea was evaluated. In vivo studies demonstrated the prooxidant effects of the o-dihydroxy phenolics caffeic acid and chlorogenic acid, as evidenced by increased levels of lipid peroxidation products, oxidized protein and free iron. Ascorbic acid levels were also depleted in larvae ingesting caffeic acid and chlorogenic acid. We propose that the induction of oxidative stress may be an important component of phenolic toxicity in lepidopteran larvae.