Identification of the Ubiquitous Antioxidant Tripeptide Glutathione as a Fruit Fly Semiochemical

Authors

Xavier Cheseto, Jomo Kenyatta University of Agriculture and Technology
Donald L. Kachigamba, USDA-ARS
Sunday Ekesi, International Centre of Insect Physiology and Ecology
Mary Ndung'u, Jomo Kenyatta University of Agriculture and Technology
Peter E. A. Teal, USDA-ARS
John J. Beck, USDA-ARS
Baldwyn Torto, International Centre of Insect Physiology and EcologyFollow

Document Type

Article

Date of this Version

2017

Citation

J. Agric. Food Chem. 2017, 65, 8560−8568, DOI: 10.1021/acs.jafc.7b03164.

Comments

U.S. government work.

Abstract

Many insects mark their oviposition sites with a host marking pheromone (HMP) to deter other females from overexploiting these sites. Previous studies have identified and used HMPs to manage certain fruit fly species; however, few are known for African indigenous fruit flies. The HMP of the African fruit fly, Ceratitis cosyra, was identified as the ubiquitous plant and animal antioxidant tripeptide, glutathione (GSH). GSH was isolated from the aqueous extract of adult female fecal matter and characterized by LC-QTOF-MS. GSH level increased with increasing age of female fecal matter, with highest concentration detected from 2-week-old adult females. Additionally, GSH levels were 5−10-times higher in fecal matter than in the ovipositor or hemolymph extracts of females. In bioassays, synthetic GSH reduced oviposition responses in conspecifics of C. cosyra and the heterospecific species C. rosa, C. fasciventris, C. capitata, and Zeugodacus cucurbitae. These results represent the first report of a ubiquitous antioxidant as a semiochemical in insects and its potential use in fruit fly management.