Related Experiment Video
Updated: May 9, 2026
Laboratory Protocol for Genetic Gut Content Analyses of Aquatic Macroinvertebrates Using Group-specific rDNA Primers
Published on: October 5, 2017
GC-MS analysis of cuticular lipids in recent and older scavenger insect puparia. An approach to estimate the
B Frere1, F Suchaud, G Bernier
1Département Environnement Incendies Explosifs (ECX), Pôle judiciaire de la gendarmerie nationale\Institut de recherche criminelle de la gendarmerie nationale, Rosny-sous-Bois, 93110, Paris, France, bertrand.frere@gendarmerie.interieur.gouv.fr.
Abstract:
An analytical method was developed to characterize puparia cuticular lipids (hydrocarbons, waxes) and to compare the molecular distribution patterns in the extracts from either recent or older puparia. Acid-catalyzed transesterification and solvent extraction and purification, followed by combined gas chromatography coupled to mass spectrometry, were optimized for the determination of hydrocarbons and fatty acid ethyl esters from transesterified waxes, extracted from a single species of a fly scavenger (Hydrotaea aenescens Wiedemann, 1830). Comparison between recent (2012) or older (1997) puparia contents has highlighted significant composition differences, in particular, a general decrease of the chain length in the n-alkane distribution pattern and, on the contrary, an increase of the ester chain length. Both extracts contain traces of three hopane hydrocarbon congeners. Preliminary results evidence the change in puparia lipid composition over time, thus potentially providing new indices for estimating postmortem interval.
