Toxicity of tomato phenolic compounds to the fruitworm, heliothis zea

TLDR: In this paper, the authors found that chlorogenic acid and rutin, major phenolic constituents of tomato foliage, as well as a phenolic-rich aqueous extract of tomato leaves, inhibit early larval growth of Heliothis zea, when added to an artificial diet for this insect.

Abstract: Chlorogenic acid and rutin, major phenolic constituents of tomato foliage, as well as a phenolic-rich aqueous extract of tomato foliage, inhibit early larval growth of the fruit-worm, Heliothis zea, when added to an artificial diet for this insect. Linear dose-response relationships between dietary concentration and inhibition of growth indicate that chlorogenic acid and rutin are equitoxic. In contrast, an uncharacterized anthocyanin isolated from tomato foliage had no inhibitory effect on H. zea. A steroidal glycoalkaloid from tomato foliage, α-tomatine, is significantly more toxic than all of the phenolics tested. Dietary concentrations of chlorogenic acid or rutin up to 1% wet weight had no adverse effects on feeding rate, digestibility and dietary utilization of food, or weight gain when fed to 3rd- or 5th-instar larvae. Early instar larvae (neonate to 2nd-instar) are sensitive to toxicosis from rutin whereas later stage larvae (3rd-5th-instars) are not, and toxicity can be overcome within 48 hr by transferring larvae from a rutin-enriched diet to control diet. RESUME Toxicite des composes phenoliques de la tomate sur Heliothis zea L'acide chlorogenique et la rutine, principaux composes phenoliques du feuillage de la tomate, aussi bien que l'extrait acqueux de feuilles riche en phenols, inhibent la croissance d'Heliothis zea. On a obtenu une relation entre la concentration dans le regime alimentaire et l'inhibition de la croissance en etudiant les chenilles neonates sur regimes impregnes de ces composes ou extraits. L'acide chlorogenique et la rutine ont ete equitoxiques pour les chenilles neonates. A l'oppose, une anthocyanine, non caracterisee, isolee du feuillage de tomate, n'a pas eu d'effet inhibiteur sur H. zea. Un glycoalcaloide steroidal (une α-tomatine) du feuillage de tomate est significativement plus toxique que tous les composes phenoliques testes. Cependant, les concentrations jusqu'a 1% w/wt d'acide chlorogenique et de rutine n'ont pas d'effets negatifs sur la consommation, la digestibilite et l'utilisation alimentaire de la nourriture, ou sur le gain de poids quand ils sont consommes par les chenilles de 3eme ou 5eme stade. Les stades precoces (neonate a 2eme stade) sont plus sensibles aux toxicoses a la rutine que les stades plus tardifs (3eme ou 5eme stade), et la toxicite peut etre surmontee dans les 48 h apres transfert des chenilles d'un regime enrichi en rutine sur un regime temoin.