Effects of Sodium Hydroxide Treatment and Ultrafiltration on the Removal of Humic Contaminants from Archaeological Bone

This study compared bone collagen extraction techniques that included treatment with sodium hydroxide and 30 kDa ultrafilters using a set of well‐preserved, humic‐contaminated archaeological marine mammal bones. Treatment with sodium hydroxide was effective at removing humic contaminants from archaeological bone, although yields were significantly decreased. Yields were also significantly decreased by ultrafiltration although this study produced no evidence that 30 kDa ultrafilters were effective at selectively removing humic contaminants from archaeological bone. The combination of sodium hydroxide treatment and ultrafiltration did not produce superior results to the treatment involving only sodium hydroxide. Archaeological samples exhibiting darker colouration indicative of humic contamination should be treated with sodium hydroxide to remove these contaminants. Copyright © 2017 John Wiley & Sons, Ltd.     

The meals in a Tuscan building yard during the Middle Age. Characterization of organic residues in ceramic potsherds

The characterization of organic residues found in ceramics objects coming from the Carmine Convent in Siena (Central Italy), probably built in the second half of the 13th century, is described. The nine objects analyzed in this study are pots, casseroles, and lids and they were used as filling material of the vault of one room of the convent.     

The potential for abiotic organic synthesis and biosynthesis at seafloor hydrothermal systems

Calculations are presented of the extent to which chemical disequilibria are generated when submarine hydrothermal fluids mix with sea water. These calculations involve quantifying the chemical affinity for individual reactions by comparing equilibrium compositions with the compositions of mixtures in which oxidation–reduction reactions are inhibited. The oxidation–reduction reactions that depart from equilibrium in these systems provide energy for chemotrophic microbial metabolism. Methanogenesis is an example of this phenomenon, in which the combination of carbon dioxide, hydrogen and methane induced by fluid mixing is far from equilibrium, which can be approached if more methane is generated. Similarly, the production of other organic compounds is also favorable under the same conditions that permit methanogenesis. Alkanes, alkenes, alcohols, aldehydes, carboxylic acids and amino acids are among the compounds that, if formed, would lower the energetic state of the chemical composition generated in mixed fluids. The resulting positive values of chemical affinity correspond to the thermodynamic drive required for abiotic organic synthesis. It is also possible that energy release accompanies biosynthesis by chemotrophic organisms. In this way, hydrothermal ecosystems differ radically from familiar ecosystems at Earth's surface. If captured, the energy released may be sufficient to drive biosynthesis of carbohydrates, purines, pyrimidines and other compounds which require energy inputs.     

Essentials in the use of mycolic acid biomarkers for tuberculosis detection: response to “High-throughput mass spectrometric analysis of 1400-year-old mycolic acids as biomarkers for ancient tuberculosis infection” by

High molecular weight long-chain mycolic acids are key structural components of the cell envelope of Mycobacterium tuberculosis and they are established as biomarkers for the identification of both ancient and modern tuberculosis. Mycolic acids from M. tuberculosis have a characteristic profile, reflecting contributions from five major distinct homologous series of mycolate structural types. Diagnosis of tuberculosis in archaeological material, using mycolic acid biomarkers, depends on objective recognition of the key characteristic mycolic acid components. A recent article in this journal claimed that tuberculosis could be confirmed in ancient bones by high throughput mass spectrometric analysis of mycolic acids. Scrutiny of the data presented reveals no convincing evidence for the presence of mycolic acids, characteristic of the M. tuberculosis complex, in the skeletal remains examined. This communication reviews the essential criteria necessary for positive tuberculosis diagnosis, using mycolic acids.     

Reconstruction of diets based on the Δ15N values of individual amino acids at three sites in Sichuan,China

This study analyzes the nitrogen isotope composition of individual amino acids in collagen extracted from human bone samples from the Gaoshan, Yingpanshan, and Xinyicun sites in Sichuan, where the isotope baseline is unavailable or incomparable with the isotopic data derived from human remains. It aims to understand the food compositions of the inhabitants at these sites, spanning the period from the late Neolithic to the middle Bronze Age, during which time agriculture and domestication of animals were introduced to the region and became increasingly important. The δ¹⁵N values of two amino acids, phenylalanine (δ¹⁵N_Phe) and glutamic acid (δ¹⁵N_Glu), indicate that the peoples on the Chengdu Plain mainly consumed terrestrial foods. The contribution of aquatic resources to their diet was limited. A possible explanation for the low dependence on aquatic foods is that the developed agriculture and domestication of animals offered sufficient foods. Such subsistence economies and dietary patterns were shaped in the early Baodun period (ca. 2,500–2000 BCE) at the latest and did not seem to change when transiting to the Bronze Age. This study also assesses the significance of these subsistence practices in supporting the social development of the Chengdu Plain.     

Probing dietary change of the Kwädąy Dän Ts'ìnchį individual,an ancient glacier body from British Columbia: II. Deconvoluting whole skin and bone collagen δC values via carbon isotope analysis of individual amino acids

The remains of the Kwäd?y Dän Ts'ìnch? individual, a frozen male human, were recovered from a retreating glacier within the Tatshenshini-Alsek Park in British Columbia in August 1999. In order to provide information on both the geographical origin of this individual and low long he spent in the remote interior region prior to his death, molecular analysis and compound-specific carbon isotope analyses were performed on individual amino acids purified from his skin and bone. Gas chromatographic quantification of constituent amino acids of both tissues revealed a molecular distribution characteristic of collagen, dominated by glycine and to a lesser extent proline, hydroxyproline and alanine. Chiral gas chromatography indicated that protein preservation in both tissues was exceptional. Carbon isotope analysis of a faunal assemblage from an earlier prehistoric site from southern British Columbia provided reference dietary amino acid δ¹³C values for terrestrial (deer and domestic dog) and marine species (salmon and sealion), showing clear separation in all amino acids, particularly glycine which was extremely ¹³C-enriched in the marine animals. The distinction between terrestrial and marine organisms was increased by exploring Δ¹³C_{Glycine-Phenylalanine} values (6.6 ± 0.6‰ and 15.0 ± 2.1‰, respectively), which were higher in the latter by approximately 8‰, mirroring the increased δ¹⁵N_{Bulk collagen} values observed for the marine animals (R² = 0.78; p < 0.001). The Kwäd?y Dän Ts'ìnch? individual's bone had a similarly elevated Δ¹³C_{Glycine-Phenylalanine} value of 15.6 ± 1.0‰, indicating his extreme reliance on marine dietary resources throughout early life. The skin amino acid δ¹³C values were consistently lower than those observed for bone, with a concurrently lower Δ¹³C_{Glycine-Phenylalanine} value of 12.7 ± 0.9‰. The shift between the carbon isotope composition of bone (long-term diet) and skin amino acids (short-term diet) confirmed a sudden divergence away from marine food sources in the last months of life, consistent with his discovery 80 km inland.     

Examination of prehistoric artifacts via fatty acid methyl ester (FAME) techniques using modern environmental stewardship

Elucidating the specific use and purpose of archaeological specimens such as stone axes and grinding stones can improve the understanding of an area's ecosystem and civilization. Chemical analysis of residues preserved on these tools may provide key information in identifying how the tool was implemented. The arid US Great Basin provides an ideal environment for the preservation of fatty acid residues.     

Adipocere withstands 1600 years of fluctuating groundwater levels in soil

An extraordinarily well-preserved skeleton of a child, interred in a stone sarcophagus in the Late-Roman era, was discovered in the city of Mainz (Germany) in 1998, covered with a puff pastry-like substance assumed to be adipocere. It is the first time that this substance, which is derived from fat under oxygen-deficient conditions and prevents corpses from decaying, has been discovered on corpses buried under conditions described in the present paper.     

Microstructural,chemical and isotopic evidence for the origin of late neolithic leather recovered from an ice field in the Swiss Alps

Archaeological leather samples recovered from the ice field at the Schnidejoch Pass (altitude 2756 m amsl) in the western Swiss Alps were studied using optical, chemical molecular and isotopic (δ¹³C and δ¹⁵N of the bulk leather, and compound-specific δ¹³C analyses of the organic-solvent extracted fatty acids) methods to obtain insight into the origin of the leather and ancient tanning procedures. For comparison, leathers from modern native animals in alpine environment (red deer, goat, sheep, chamois, and calf/cow) were analyzed using the same approach. Optical and electron microscopically comparisons of Schnidejoch and modern leathers showed that the gross structure (pattern of collagen fibrils and intra-fibrils material) of archaeological leather had survived essentially intact for five millennia. The SEM studies of the hairs from the most important archaeological find, a Neolithic leather legging, show a wave structure of the hair cuticle, which is a diagnostic feature for goatskins. The variations of the bulk δ¹³C and δ¹⁵N values, and δ¹³C values of the main fatty acids are within the range expected for pre-industrial temperate C₃ environment. The archaeological leather samples contain a mixture of indigenous (from the animal) and exogenous plant/animal lipids. An important amount of waxy n-alkanes, n-alkan-1-ols and phytosterols (β-sitosterol, sitostanol) in all samples, and abundant biomarker of conifers (nonacosan-10-ol) in the legging leathers clearly indicate that the Neolithic people were active in a subalpine coniferous forest, and that they used an aqueous extract of diverse plant material for tanning leather.     

Chemical analyses of organic residues in archaeological pottery from Arbon Bleiche 3, Switzerland – evidence for dairying in the late Neolithic

Fatty acids distribution and stable isotope ratios (bulk δ¹³C, δ¹⁵N and δ¹³C of individual fatty acids) of organic residues from 30 potsherds have been used to get further insights into the diet at the Late Neolithic (3384–3370 BC) site of Arbon Bleiche 3, Switzerland. The results are compared with modern equivalents of animal and vegetable fats, which may have been consumed in a mixed ecology community having agrarian, breeding, shepherd, gathering, hunting, and fishing activities. The used combined chemical and isotopic approach provides valuable information to complement archaeological indirect evidence about the dietary trends obtained from the analysis of faunal and plant remains. The small variations of the δ¹³C and δ¹⁵N values within the range expected for degraded animal and plant tissues, is consistent with the archaeological evidence of animals, whose subsistence was mainly based on C₃ plants. The overall fatty acid composition and the stable carbon isotopic compositions of palmitic, stearic and oleic acids of the organic residues indicate that the studied Arbon Bleiche 3 sherds contain fat residues of plant and animal origin, most likely ruminant (bovine and ovine). In several vessels the presence of milk residues provides direct evidence for dairying during the late Neolithic in central Europe.