The aim of this study was to compare three different collection methods; purge and trap, solid phase micro extraction and automated dynamic headspace/thermal desorption, all followed by GC–MS analysis used for the measurements of concentrations of volatile oxidation products in three different food matrices, namely oil, emulsion and milk. The linearity ranges of calibration curves obtained by the three different methods were compared for oil samples. Overall, the results showed that the three collection methods were comparable, although there were large differences in the linearity range of the calibration curves depending on the collection method. However, some challenges were observed for solid phase micro extraction and automated dynamic headspace/thermal desorption, namely, competition problems and overestimation of concentration by calibration curves, respectively. Based on the results, we suggest mainly to apply solid phase micro extraction on simple matrices and to be cautious with more complex matrices such as enriched milk and highly oxidized oils. Thereby, the study confirmed some challenges observed by other authors regarding competition problems on the fiber when using solid phase micro extraction. Furthermore, we observed that purge and trap, and automated dynamic headspace/thermal desorption were excellent for extraction of volatile compounds in all three matrices. However, automated dynamic headspace/thermal desorption calibration curves did provide an overestimation for oil samples so results must be interpreted with caution.

Knowledge about the healing properties of plant substances is probably as old as humankind, and this can be demonstrated by botanical finds in archaeological contexts. Southern Scandinavia has a long tradition of supplying deceased persons with vegetal material for use in their afterlife, as shown by single seeds or processed plants in the form of foods, drinks or medicines. A wellknown example is the small container made of birch bark most probably filled with a kind of mead produced from honey, in the Egtved girl's coffin a find which has been dated to the Early Bronze Age.Another fascinating plant discovery derives fromthe grave of the Fyrkat woman dated to the Viking Age: a handful seeds of the poisonous plant henbane (Hyoscyamus niger) was found in a small pocket fixed to the woman's belt. Plant materials enclosed in small amulet boxes are quite common and are frequently attached to necklaces that the deceased had certainly worn during their lives. In this article, we discuss the organic finds from a newly excavated amulet box which was discovered in a woman's grave at the Late Roman Iron Age site of Vellensby, on the island of Bornholm. The box contained two 'chewing gum-like objects' with dental impressions and three vegetal objects. Gas chromatography/mass spectrometry analysis was applied to one of the 'chewing gums' and the results show that it consists of a mixture of birch tar and plant oil. Based on their morphological characteristics, the three uncharred plant parts could be identified as cloves from a wild species of Allium, probably A. scorodoprasum (sand leek). The traditional medicinal application of sand leek is presented and the symbolic and possible principal meaning of amulet boxes is discussed within a comparative study of related discoveries from female burials throughout Europe.

The degradation of tetraethylene glycol (TEG) was studied at 70 degrees C under dry air and nitrogen. Degradation products were detected using gas chromatography-mass spectrometry (GC MS). They were mono-, di- and tri-ethylene glycol, mono- and di-formates of mono-, di-, tri- and tetra-ethylene glycol and formic acid. The rate of TEG degradation was significantly decreased by approximately 10 mmol/l KI, FeCl3, Cu(CH3COO)(2). MnO2 and CuSO4. small amounts of fresh oak wood sawdust and gypsum-containing scrapings from the wood surface of the Vasa ship in Stockholm. Thus certain salts and natural components of archaeological wood are able to inhibit oxidative degradation of TEG. NaFe3(SO4)(2)(OH)(6) (Natrojarosite), FeS2 (pyrite), FeSO4, Fe-2(SO4)(3), NiCl2, NiSO4, Fe, Cu, Fe2O3, Cu, NaHSO4 and natrojarosite-containing scrapings from the Vasa had no major effect on the rate of oxidation. (C) 2012 Elsevier Ltd. All rights reserved.

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A novel halophilic Gram-negative sulfate-reducing bacterium affiliated with the deltaproteobacterial family Desulfobacteraceae, strain PropA(T), was isolated from the extreme hypersaline sediment of the northern arm of Great Salt Lake, Utah, USA. Comparative 16S rRNA gene sequence analysis showed that strain PropA(T) is the first cultured representative of a clade of phylotypes that have been retrieved from a range of geographically and ecologically distinct hypersaline environments. Strain PropA(T) shared < or =90 % 16S rRNA gene sequence identity with cultured strains within the family Desulfobacteraceae. Cells of strain PropA(T) were rod-shaped and sometimes motile. The strain required NaCl for growth and grew at salinities up to 200 g NaCl l(-1) (optimum 60 g l(-1)). Growth was observed at 15-40 degrees C, optimum growth occurred at about 40 degrees C, while growth was absent at 10 and 45 degrees C. The pH range for growth was pH 6.0-8.3. Yeast extract (0.1 g l(-1)) was required for growth. C(2-4) alcohols, C(3-4) carboxylic acids, yeast extract and H(2)/acetate supported growth with sulfate as electron acceptor. Sulfate, thiosulfate and sulfite served as electron acceptors, but not elemental sulfur, nitrate or fumarate. The DNA G+C content of strain PropA(T) was 54.1 mol%. Based on the genotypic and physiological properties, we propose that strain PropA(T) represents a novel species within a novel genus, Desulfosalsimonas propionicica gen. nov., sp. nov. The type strain of Desulfosalsimonas propionicica is PropA(T) (=DSM 17721(T) =VKM B-2385(T)).

A method has been developed to analyse and quantify formic and acetic acids in archaeological and fresh wood. The method takes advantage of the fact that, in equilibrium, the gas-phase concentrations of formic and acetic acids over pulverised archaeological wood in a sulfuric acid solution are proportional to their absolute concentrations in wood. The method is based on automated solid-phase micro extraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS). Good linearity of the calibration curves was observed. The content of formic and acetic acids in archaeological wood from ships conserved with polyethylene glycol (PEG) was determined. The content of formic acid is related to the intensity of conservation and, hence, the PEG content in wood. Accordingly, formic acid found in the hull of the ships may partly be a result of PEG degradation. The formic acid content in the Vasa warship is, on average, not higher than in the other ships analysed. In contrast, the acetic acid content in PEG-preserved archaeological wood is lower than in fresh wood. The acetic acid content is age-dependent and is lowest in 1000-year-old wood. The acetic acid probably originates from the wood.

The Swedish 17th century warship Vasa and the Danish Skuldelev Viking ships from the 11th century were impregnated with polyethylene glycol (PEG) in the 1960s. The molecular weight, amount and integrity of this PEG were investigated at a range of depths below the wood surface. Large amounts of PEG could be extracted from degraded parts of the ships but hardly any from sound parts. Mass spectrometry showed that PEG 4000 is present only in the surface layers of the wood, PEG 1500 and PEG 600 are present at all depths of the wood that has been treated with it. Low molecular weight PEG was detected in one of the Skuldelev ships by mass spectrometry and Size Exclusion Chromatography (SEC), it is argued that this is due to degradation of PEG 4000. SEC also showed that PEG 600 is the major PEG component in the Vasa which makes this particular object sensitive to changes in air humidity since PEG 600 is hygroscopic.

Polyethers are subject to oxidative degradation. An examination of the possible degradation mechanisms suggests a protective substitution, which has been shown to be effective on short chain polyglycols. Inserting a methylene group at the end of triethylene and tripropylene glycols, between the hydroxyl and ether groups, has a stabilising effect on their degradation in air. At 70 degreesC, degradation is completely stopped in modified triethylene glycol, while modified tripropylene glycol shows diminished degradation. (C) 2003 Elsevier Science Ltd. All rights reserved.

A Phoenician shipwreck dated to 400 B.C. has paint layers on the wooden planks. Five samples were taken from different points for analysis of the binding medium using gas chromatography/mass spectrometry. The results suggest that the painting medium was esparto wax mixed with resin, and that an encaustic technique was used.

In Norway there is a living tradition for softwood tar production in a kiln. Kiln-productions has been documented with respect to choice of wood, design, burning and collection of the tar. Tar samples were collected at intervals during burning, analysed and characterised with GC-MS. The tar fractions from an early stage of the production are different from the frac- tions from a later stage, probably as a result of the heat and the relatively reducing conditions under which the production takes place.