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1.
Molecules ; 27(13)2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35807349

RESUMO

Charles T. Currelly, first director of the Royal Ontario Museum, participated in excavations of the tomb of King Nebhepetre, now known as Mentuhotep II, (Dynasty XI) in Deir el-Bahri, Egypt in 1906. He brought to Canada many objects from the excavations, and objects that he purchased while in Egypt; these formed the initial collection of the museum. Among the objects were seven fragments of fine linen cloth with intricate pleat patterns. Recently, the cloths became the subject of a study to learn how they had retained their pleats for 4000 years. Samples were examined and analysed using polarised light microscopy, scanning electron microscopy-electron dispersive X-ray spectrometry, gas chromatography-mass spectrometry, and pyrolysis-gas chromatography-mass spectrometry. Three of the cloths were likely fragments of clothing re-purposed as bandages and were found to be saturated in mummification balms composed of Pinaceae resin, Pistacia resin, and an essential oil characterised by a high abundance of cedrol, possibly originating from a juniper species. All seven of the cloths were found to have traces of polysaccharides from two probable sources: an arabinogalactan gum such as gum arabic or a fruit gum, and a polyglucoside, possibly starch.


Assuntos
Múmias , Egito , Cromatografia Gasosa-Espectrometria de Massas , Goma Arábica , Têxteis
2.
Anal Chem ; 86(15): 7428-35, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-24945921

RESUMO

For the first time, molecular evidence of the structural role played by succinic acid within the macromolecular structure of Class Ia and Class Id resinite is presented. Using a novel gas chromatographic methodology, communol (Class Ia) and ozol (Class Id) moieties within the polylabdane matrix are shown to be cross-linked with succinic acid. Samples were analyzed using pyrolysis-gas chromatography-mass spectrometry with in situ hexamethyldisilazane derivatization, using a thermal separation probe to perform the pyrolysis and sample introduction. The relatively slow rate of heating and prolonged pyrolysis of resinites using this new methodology, combined with the use of a mild derivatization reagent, allowed communol pyrolysates from Class Ia resinite and ozol pyrolysates from Class Id resinite to elute with unbroken succinyl ester cross-linkages. These results provide direct molecular evidence that the key role of succinic acid within Class Ia and Class Id resinite is to cross-link the macromolecular structure. In the Class Id resinite, the methodology also allowed the detection of succinyl ester linkages between ozol pyrolysates and dehydroabietol, thus demonstrating that nonpolymerized diterpenes contribute structurally to the macromolecular structure of Class Id resinite.


Assuntos
Âmbar , Ácido Succínico/química , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Reprodutibilidade dos Testes
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