title: The chemistry of the postpharyngeal gland of female European beewolves.
abstract: Females of the European beewolf, Philanthus triangulum, possess a large glove-shaped gland in the head, the postpharyngeal gland (PPG). They apply the content of the PPG to their prey, paralyzed honeybees, where it delays fungal infestation. Here, we describe the chemical composition of the gland by using combined GC-MS, GC-FTIR, and derivatization. The PPG of beewolves contains mainly long-chain unsaturated hydrocarbons (C23-C33), lower amounts of saturated hydrocarbons (C14-C33), and minor amounts of methyl-branched hydrocarbons (C17-C31). Additionally, the hexane-soluble gland content is comprised of small amounts of an unsaturated C25 alcohol, an unknown sesquiterpene, an octadecenylmethylester, and several long-chain saturated (C25, C27) and unsaturated (C23-C27) ketones, some of which have not yet been reported as natural products. Surprisingly, we found a dimorphism with regard to the major component of the PPG with some females having (Z)-9-pentacosene, whereas others have (Z)-9-heptacosene as their predominant component. The biological relevance of the compounds for the prevention of fungal growth on the prey and the significance of the chemical dimorphism are discussed.
authors.affiliation: Department of Zoology, University of Regensburg, 93040 Regensburg, Germany. erhard.strohm@biologie.uni-regensburg.de
authors.forename: Erhard
authors.initials: E
authors.lastname: Strohm
authors.forename: Gudrun
authors.initials: G
authors.lastname: Herzner
authors.forename: Martin
authors.initials: M
authors.lastname: Kaltenpoth
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Boland
authors.forename: Peter
authors.initials: P
authors.lastname: Schreier
authors.forename: Sven
authors.initials: S
authors.lastname: Geiselhardt
authors.forename: Klaus
authors.initials: K
authors.lastname: Peschke
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmitt
mesh_terms: D000818:Animals; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D010614:Pharynx / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014863:Wasps / Q000737:chemistry*