Organic substances from Egyptian jars of the Early Dynastic period (3100–2700 BCE): Mode of preparation, alteration processes and botanical (re)assessment of “cedrium”

Abstract

Organic substances from three jars found at Abydos in the tombs of Kings from the two first Egyptian dynasties (3100-2700 B.C.) were investigated using gas chromatography-mass spectrometry in order to assess their biological origin, use and mode of preparation. The organic material was found to correspond to essential oils from conifers severely altered/oxidized. A predominant contribution from Cedrus libani was determined from the identification of sesquiterpenoid derivatives of the himachalene series which constitute new molecular tools for the identification of ancient oils made from real cedars. The presence of cuparene-related terpenoids suggested an additional contribution of members from the Cupressaceae family (junipers, cypresses). The genuine substances were most likely prepared in the Levant since neither C. libani nor junipers or cypresses are native from Egypt. Despite obvious analogies with "cedrium" used for embalming during later periods, their use as ingredients for embalming remains uncertain because true embalming only begun in Egypt after 2500 BC. Instead, it is proposed that these substances have been used as cosmetics, medicinal substances or for cultual purposes. The predominance of low molecular weight sesquiterpenoids and the absence of typical markers for wood tars indicate that the substances have possibly been prepared by steam-distillation of odoriferous plant material rather than by pyrolysis. Our study gives clues to the controversy concerning the composition of "cedrium", indicating that it most likely originates from mixed true cedar and junipers or cypresses, and not exclusively from real cedar vs. juniper oil.

Chemical Modification of Biomarkers through Accelerated Degradation: Implications for Ancient Plant Identification in Archaeo-Organic Residues

“…Our findings can be compared to results from analyses of archaeological plant residues which were identified as plant products from cedar [ 41 ] where dehydrogenated analogues of sesquiterpenoids from himachalenes (e.g., #033 and #038) were also detected, while G1 himachalenes were absent. The similarities between archaeological findings and our accelerated degradation experiments underline the potential for expanding accelerated degradation studies to terpenoids from other plants, as well as to compounds belonging to other natural product classes.…”

“…Each of the samples was dissolved in 500 μL of CH 2 Cl 2 and quickly (~5 s) mixed by vortexing. Essential oils and wood tars are in general completely soluble in CH 2 Cl 2 , which did not require additional extraction steps [ 41 ]. After letting samples rest for 5–10 min for settling of solid remains (catalysts), 10 μL of the extracts were taken out with glass capillaries into 1.5 mL combusted glass vials and diluted with 490 μL of CH 2 Cl 2 for GC-MS analysis of the volatile fraction, which was carried out immediately afterwards.…”

“…To date, there has been relatively little exploration of the potential and nature of secondary metabolite degradation to occur in plant residues, including resins, gums, tars, essential oils, spices, herbs, and psychoactive plant products. This is despite their widespread application in past medicinal, culinary, sanitary, cosmetic, ritual, and economic contexts [ 1 , 6 , 8 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ]. Here, we investigate the transformation processes influencing the phytochemical composition of secondary metabolites from a selected plant source to gain a fundamental understanding of the chemical alterations associated with chemical degradation processes in ancient samples.…”

“…By applying multivariate analysis to these complex data sets, we identify characteristic biomolecular profiles associated with the various degradation treatments. We use the oil of cedar trees ( Cedrus atlantica ) for the experiment, as coniferous plant products from the Pinaceae family are frequently found in organic residues from archaeological contexts, especially in artefacts from ancient Egypt [ 17 , 18 , 41 , 45 , 46 , 47 , 48 , 49 ]. Cedar essential oil is mainly composed of mono- and sesquiterpenes, with himachalenes as the main components [ 50 ].…”

Molecular analysis of black coatings and anointing fluids from ancient Egyptian coffins, mummy cases, and funerary objects

“…αR-Himachalene and cuparene were both observed in scan mode in some of the samples prepared by method B (C2 type 2; C5 type 1 and type 2; C13 type 2). Sarret and colleagues analyzed black residue from an Egyptian jar dating to the first or second Dynasty c. 3100 to 2700 BC and also identified both himachalene compounds and cuparene ( 52 ). They suggested that the himachalene compounds were evidence for the use of a product from Cedrus libani , and cuparene was evidence for the use of a product from the Cupressaceae family of junipers and cypresses.…”