Reassessment of the role of gut alkalinity and detergency in insect herbivory

Previously it was reported that significant amounts of the tomato phenolic, chlorogenic acid, were oxidized in the digestive system of generalist feeder Spodoptera exigua and Helicoverpa zea. The covalent binding of the oxidized phenolic (i.e., quinone) to dietary protein exerts a strong antinutriti...

Full description

Saved in:
Bibliographic Details
Published in:Journal of chemical ecology 1991-09, Vol.17 (9), p.1821-1836
Main Authors: Felton, G.W. (University of Arkansas, Fayetteville, AR), Duffey, S.S
Format: Article
Language:English
Subjects:
ALCALINIDAD
ALCALINITE
ALLOMONE
ALOMONAS
Animal and plant ecology
Animal, plant and microbial ecology
Animals
Autoecology
Biological and medical sciences
CATECHOL OXYDASE
CATECOL OXIDASA
COMPORTEMENT ALIMENTAIRE
COMPOSICION QUIMICA
COMPOSITION CHIMIQUE
CONTROL BIOLOGICO
CONTROL DE INSECTOS
FEUILLE
Fundamental and applied biological sciences. Psychology
HABITOS ALIMENTARIOS
HOJAS
INTESTIN
INTESTINOS
Invertebrates
Lepidoptera
LUTTE ANTIINSECTE
LUTTE BIOLOGIQUE
LYCOPERSICON
MANDUCA SEXTA
Protozoa. Invertebrata
Sphingidae
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Previously it was reported that significant amounts of the tomato phenolic, chlorogenic acid, were oxidized in the digestive system of generalist feeder Spodoptera exigua and Helicoverpa zea. The covalent binding of the oxidized phenolic (i.e., quinone) to dietary protein exerts a strong antinutritive effect against larvae. In this study, we examined the fate of ingested chlorogenic acid in larval Manduca sexta leaf-feeding specialist of solanaceous plants. Significant amounts of chlorogenic acid were bound to excreted protein by M. sexta when larvae fed on tomato foliage. However, in the case of M. sexta we suggest that the strong alkalinity and detergency of the midgut may minimize the antinutritive effects of oxidized phenolics. The solubility of tomato leaf protein is significantly greater at pH 9.7, representative of the midgut of M. sexta than at pH 8.0, representative of the midguts of H. zea and S. exigua. We suggest that this increase in solubility would compensate for any loss in bioavailability of essential amino acids caused by the covalent binding of chlorogenic acid to amino acids. Furthermore. lysolecithin, a surfactant likely to contribute to the detergent properties of the midgut fluid, was shown to enhance protein solubility as well as inhibit polyphenol oxidase activity. The adaptive significance of gut alkalinity and detergency is discussed
ISSN:0098-0331
1573-1561
DOI:10.1007/bf00993731