E16444 Molecular study of organic residues in archaeological pottery from Egypt (XVIII th dynasty) Claire Bastien 1, Armelle Charrié-Duhaut 1, Jacques Connan 1, Geneviève Pierrat-Bonnefois 2 1 Laboratoire de Biogéochimie Moléculaire, UMR 7177 CNRS, UDS, 25 rue Becquerel, Strasbourg Cedex 02 2 Département des Antiquités Egyptiennes, Musée du Louvre, Porte des Arts, Paris Cedex 01 INTRODUCTION : Within this study of molecular archaeology, an exceptional set of Egyptian organic remains stored in containers from Deir el-Médineh (XVIII th dynasty) and put at disposal by the Louvre Museum, has been analysed. The containers, still full and covered, were found in a necropolis located on the east side of the valley. One of the aims of this study was to determine the nature of the necropolis by the identification of the substances present in the containers. The caracterization of materials is based on the precise structural identification of biomarkers (for example fatty acids for fats or oils, wax esters for beeswax…), their alteration products and their distributions. ANALYTICAL PROCEDURE : The samples were extracted with DCM/MeOH. The total organic extract was separated according to different polarities by column liquid chromatography and thin layer chromatography resulting in fractions of aliphatic and aromatic hydrocarbons, esters, ketones (and triacylglycerols), alcohols, acids and polyfunctionalized compounds. Analysis was performed using GC-MS, GC-C-IRMS and LC-MS. CONCLUSION : The first results acquired on fifteen samples showed two distinct groups of samples. The first group contains only plant-derived lipids (like epicuticular waxes, cutin or suberin…). The second group seems to be a mixture beetween these plant-derived lipids and animal fat or vegetable oil (siccative oil like linseed, sesame oil). [1] M.S. Copley et al., J. Archaeolog Sci., 32, 2005, [2] R.P. Evershed et al., Philos. Trans R. Soc. London Ser. B, 354, 1999, E16439 E16449 Second group : mixture between animal fat or vegetable oil and plant products The presence of archaeological fats can be revealed by different mass spectrometric techniques. First group : samples with plant- derived lipids Characterized by specific distributions [1] of : n-alkanes (principally C 27 -C 33 ) n-alcohols (principally C 24 -C 34 ) Phytosterols Palmitic and stearic wax esters (C 40 -C 52 ) γ-lactones α,ω-dicarboxylic acids E (Camaret tallow) PPM OOP OPP PPP SOP+SPO PSO SPP MaPS SSP SSS MaSS ASS AAP RIC (LC-MS) GC-MS GC-C-IRMS LC-MS Direct insertion probe mass spectrum of a ketone fraction. The labelled fragments are characteristic for triacylglycerols. ID-EI E16446 TIC E14602 C 16 C 18 C 17 C 19 C 20 C 15 C 14 C 13 C 12 C 11 C 10 Total ion current of a ketone fraction showing a series of lactones with m/z 85. TIC E16478 Total ion current of a polyfonctionalized fraction showing a series of α,ω-dicarboxylic acids. samples of the first type ♦ samples of the second type within the Evershed’s model [2]. Reconstructed liquid chromatography mass spectrum (RIC) of the triacylglycerols. γ-lactones α,ω-dicarboxylic acids They may be the transformation products of fatty acids originating from plants. They are transformation products of unsaturated fatty acids of vegetable oil or may indicate the use of cutin or suberin. BIOMARKERS DETAILS :