Extracting natural dyes from wool—an evaluation of extraction methods

The efficiency of eight different procedures used for the extraction of natural dyes was evaluated using contemporary wool samples dyed with cochineal, madder, woad, weld, brazilwood and logwood. Comparison was made based on the LC-DAD peak areas of the natural dye’s main components which had been extracted from the wool samples. Among the tested methods, an extraction procedure with Na2EDTA in water/DMF (1:1, v/v) proved to be the most suitable for the extraction of the studied dyes, which presented a wide range of chemical structures. The identification of the natural dyes used in the making of an eighteenth century Arraiolos carpet was possible using the Na2EDTA/DMF extraction of the wool embroidery samples and an LC-DAD-MS methodology. The effectiveness of the Na2EDTA/DMF extraction method was particularly observed in the extraction of weld dye components. Nine flavone derivatives previously identified in weld extracts could be identified in a single historical sample, confirming the use of this natural dye in the making of Arraiolos carpets. Indigo and brazilwood were also identified in the samples, and despite the fact that these natural dyes were referred in the historical recipes of Arraiolos dyeing, it is the first time that the use of brazilwood is confirmed. Mordant analysis by ICP-MS identified the widespread use of alum in the dyeing process, but in some samples with darker hues, high amounts of iron were found instead

Deus está nos detalhes. Ouro, prata e policromia

The visible polychromy of a wooden sculpture representing St. John the Evangelist, from Museu Nacional de Arte Antiga, Lisbon (Portugal) presents several techniques that complement each other on the creation of a sumptuous estofado. This case-study allowed the survey on gilding, silvering and polychromy practices, and observations on their execution are briefly reported and documented with results from a multi-analytical approach. Examination included digital photomicrography and the observation of micro-samples cross-sections, while material identification resorted to several analytical methods that included scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray diffraction (XRD).La policromía visible de una escultura de madera representando a San Juan Evangelista, de Museu Nacional de Arte Antiga, Lisbona (Portugal) presenta varias técnicas que se complementan en la creación de un estofado suntuoso. Este estudio de caso permitió el examen de procesos de dorado, plateado y policromía, y las observaciones a su ejecución son reportadas y documentadas con resultados del enfoque multi-analítico. El examen incluyó fotomicrografía digital y observación de secciones transversales de muestras de policromía, la identificación material recurriendo a diversos métodos analíticos, incluyendo microscopía electrónica de barrido con espectroscopia de rayos X (SEM-EDS) y difracción de rayos X (XRD).A policromia visível de uma escultura em madeira representando S. João Evangelista, do Museu Nacional de Arte Antiga, Lisboa (Portugal) apresenta várias técnicas que se complementam na criação de um sumptuoso estofado. Este caso de estudo permitiu o exame de processos de douramento, prateamento e policromia, sendo as observações da sua execução reportadas e documentadas com os resultados de uma abordagem multi-analítica. O exame incluiu fotomicrografia digital e observação de cortes transversais de amostras de policromia, recorrendo a identificação material a vários métodos analíticos, incluindo microscopia eletrónica de varrimento associada a espectroscopia raios-X por dispersão de energia (SEM-EDS) e difração de raios-X (XRD)

Combination of stable isotope analysis and chemometrics to discriminate geoclimatically and temporally the virgin olive oils from three mediterranean countries

The knowledge of the isotopic composition of virgin olive oil (VOO) allows the evaluation of authenticity and geographical origin, being an important tool against fraud. This study aimed to assess if VOOs produced in three Mediterranean regions could be discriminated on the basis of multivariate statistical analysis of geoclimatic and isotopic data. A total of 138 geo-referenced VOO samples from Portugal, France and Turkey from two different cultivation years were collected. The isotopic composition (δ13C, δ2H and δ18O) of VOOs was obtained using an elemental analyzer coupled to an isotope ratio mass spectrometer (EA-IRMS). One-way analysis of variance for δ13C, δ2H and δ18O showed some significant differences either between crop years or geoclimatic conditions. Based on multiple regression analyses using meteorological and geographical parameters, a meteoric water line for olive oil from Portugal, France and Turkey, in two harvest years, were created to assess the impact of climate change on their δ2H and δ18O values. Principal component analysis and Linear Discriminant Analysis, used to sort samples according to geoclimatic origin, performed best for French and Portuguese olive oils. In light of the results, multivariate isotopic analysis of VOO samples may discriminate not only between geoclimatic regions but also among cultivation years

Archaeological evidence for the dietary practices and lifestyle of 18th Century Lisbon, Portugal. Combined steroidal biomarker and microparticle analysis of the carbonized faecal remains

The study of the urban context in the contemporary center of Portugal’s capital city uncovered traces of daily lives that were abruptly interrupted and utterly transformed by the Great Lisbon Earthquake on the morning of 1 November 1755. Charred organic residue was recovered from a cylindrical vessel excavated from the storage area of the town house at the Rossio square. The archaeological sample was studied through a multi-analytical approach based on microstructural, elemental and biomolecular characterization by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FT-IR), variable pressure scanning electron microscopy coupled to energy dispersive X-ray spectroscopy (VP-SEM-EDS), and gas chromatography coupled with mass spectrometry (GC-MS). The residue was identified as human faeces collected in the ceramic vessel for disposal, and further analysis provided additional information about diet and the living conditions in the 18th century

The Wooden Roof Framing Elements, Furniture and Furnishing of the Etruscan Domus of the Dolia of Vetulonia (Southern Tuscany, Italy)

The Etruscan Domus of the Dolia remained hidden until 2009, when archaeological excavations began in the Etruscan–Roman district of Vetulonia (Southern Tuscany). Based on the classification of the archaeological materials recovered, the destruction of the Domus and the Etruscan city of Vetulonia was traced back to the 1st century BC. The highly various and precious materials recovered inside the Domus revealed the richness of the building and its inhabitants. With this study, we present the anthracological analyses from the Domus of the Dolia. Wood charcoals were recovered from different house rooms, which had different functions based on the archaeological evidence. The tree species employed for the construction of the roof of the building were deciduous and semi-deciduous oak wood (Quercus sect. robur, Quercus sect. cerris) and silver fir wood (Abies cf. alba). Evergreen oak wood (Quercus sect. suber), boxwood (Buxus sempervirens), beech wood (Fagus cf. sylvatica), maple wood (Acer sp.) and cherry wood (Prunus cf. avium) were adopted for the furniture and furnishings of the house. Moreover, wood charcoal fragments of fruit trees belonging to the family of Rosaceae were identified, documenting a possible garden inside the court of the house. The study shows the use of the local tree species primarily. The silver fir wood and beech wood were likely sourced from the nearby (roughly 60 km) Mount Amiata

On the origin of Goa Cathedral former altarpiece: Material and technical assessment to the work of Garcia Fernandes, Portuguese painter from 16th century Lisbon workshop

Goa Cathedral former altarpiece is one of the oldest set of paintings in India. The seven remaining paintings from the first altarpiece of Goa Cathedral, nowadays in the sacristy, are attributed by some art historians to Master Garcia Fernandes (act. 1514–1565), Portuguese painter from Lisbon workshop. The 16th century was the “Golden age” of Portuguese painting. In this context the Royal Lisbon workshop played a predominant role, where the activity of the painter Garcia Fernandes and his workshop can be distinguished. In this new approach, Goa paintings are being studied and compared with other works in Portuguese territory attributed to this same painter, as St. Bartholomew altarpiece from the chapel of Bartolomeu Joanes in Lisbon Cathedral. The stratigraphic study allowed to compare ground layers, pigments and binders which, were characterized using complementary analytical and imaging techniques: (X-ray Fluorescence spectrometry (XRF), Infrared Reflectography (IRR), Infrared Photography (IRP), Macro Photography (MP), micro-X-ray Diffraction (μ-XRD), Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS), Raman micro-spectroscopy (μ-Raman), Fourier Transform Infrared micro-spectroscopy (μ-FTIR), Pyrolysis gas chromatography mass spectrometry (PY-GC/MS). This work brought a new insight on the techniques and materials used in this Masterpiece and highlighted the conclusion that Goa Cathedral former altarpiece must be a Portuguese production

Caracterização material das técnicas de douramento e pintura de um ícone pós-bizantino

This study aims to identify the materials used in the production of a post-byzantine icon from the Museum of Évora’s collection. The icon, representing the “Emperor Constantine and his mother Helen holding the Holy Cross” was once dated as being from the 10th century. Throughout a multi-analytical approach, combining area exams with spectroscopic techniques, this study tried to confirm its actual chronology. The results obtained revealed that it is most likely an icon from the late 17th or 18th century.El presente estudio tuvo como objetivo la identificación de los materiales utilizados en la producción de un icono pos bizantino perteneciente a la colección del Museo de Évora. Este icono tiene representado el “Emperador Constantino y su madre Elena manifestando la Cruz” y había sido datado del siglo X. A través de un abordaje diversificado, combinando exámenes de área con técnicas espectroscópicas, hemos intentado confirmar su datación. Los resultados obtenidos han revelado que será probablemente un icono de finales del siglo XVII o incluso del siglo XVIII.Este estudo teve como objetivo a identificação dos materiais utilizados na produção de um ícone pós-bizantino pertencente à coleção do Museu de Évora. Este ícone, representando o “Imperador Constantino e a sua mãe Helena manifestando a Cruz”, foi datado como sendo do século X. Através de uma abordagem analítica diversificada, combinando exames de área com técnicas espectroscópicas, tentámos confirmar a sua datação. Os resultados obtidos sugerem que será provavelmente um ícone dos finais do século XVII ou do século XVIII

Diet and disease in Tomar, Portugal: comparing stable carbon and nitrogen isotope ratios between skeletons with and without signs of infectious disease

Objectives: This study explored the correspondence between stable isotope ratios and indicators of non-specific (periostitis and/or osteomyelitis) and specific (venereal syphilis) disease in a sample of human skeletons from a Portuguese archaeological collection. Additionally, this study examined stable carbon (δ13C) and nitrogen (δ15N) isotope ratios between individuals at different disease stages. Materials and Methods: δ13C and δ15N data from previously analysed skeletons without signs of infectious disease or physiological stress (n=32) were compared to new data from skeletons with active (n=6), healed (n=7) or a combination of both lesions (n=10). Skeletons with lesions (n=23) were also grouped as having only healed tibial periostitis (n=7), generalised non-specific (n=5) and generalised specific infections (n=2). The skeletons with lesions that did not fit into these groups (n=9) were not used in this analysis. Results: The δ15N from skeletons with non-specific generalised infections in several bones differed significantly when compared to skeletons that had either only healed tibial periostitis or were without lesions. Skeletons with venereal syphilis had similar mean δ13C and δ15N to either skeletons without signs of disease or those with only healed tibial periostitis. Discussion: These results suggest different diets may be linked into an individual’s susceptibility to these pathogens. Diet influences resistance to infectious disease, while infections decrease nutrient availability, increase malabsorption and resting energy expenditure. Potentially therefore, combining isotopic evidence of diet with pathology may contribute to a new understanding of health and lifestyle in the past

Understanding the chemical and mineralogical composition of commercial henna and jagua tattoos and dyes – a multi-analytical approach

Temporary tattoos and dyes constitute a great analytical challenge in relation to the regulatory control of their ingredients. Most of these commercial products are not labeled according to their content and their chemical nature is highly diverse. Therefore, it is necessary to analyze these complex samples to evaluate the potential presence of metallic impurities, to ensure the safety of cosmetic products contributing to health protection. This study proposes a multi-analytical methodology, which includes handheld X-ray fluorescence (h-XRF) and X‐ray diffraction (XRD), complemented by variable pressure scanning electron microscopy coupled with energy-dispersive X‐ray spectrometry (VP-SEM–EDS) to fully characterize 34 commercial samples of jagua and henna tattoos and dyes. The approach allowed the identification of the main constituents providing complementary compositional data and differences between sample types were established. In addition, information on the degree of natural pigments homogeneity was also obtained. The results’ discussion considering the current European cosmetics regulation may be useful to support the drafting of safety requirements and specific regulation

Multivariate geostatistical analysis of stable isotopes in Portuguese varietal extra virgin olive oils

Stable isotope contents of carbon, hydrogen and oxygen are known to reflect the geo-climatic conditions under which olives grown. This study aims to unravel the correlation between some of the main geographic variables and the isotopic composition of different Portuguese varietal extra virgin olive oil (EVOO) samples. Thus, the isotopic composition (δ13C, δ18O and δ2H) of 38 EVOO samples from 11 olive varieties from 2 Portuguese regions (Alentejo and Trás-os-Montes) was studied using an elemental analyzer coupled to an isotope ratio mass spectrometry. Multivariate analysis indicated that bulk δ13C, δ2H and δ18O values were enough to significantly (P < 0.05) predict altitude, latitude, longitude, temperature, rainfall, and sea distance. This work showed that the assessment of EVOO isotopic composition give information not only on the geographic origin, but also on the environmental conditions. To the best of our knowledge, this is the first report on bulk isotopic composition of Portuguese EVOOs.This work was funded by European Regional Development Fund (FEDER) and National Funds through Foundation for Science and Technology (FCT) under Project “Por3O - Portuguese Olive Oil Omics for traceability and authenticity - PTDC/AGRPRO/2003/2014, and by National Funds through FCT - Foundation for Science and Technology under the Projects UIDB/05183/2020 and UID/AGR/00690/2019. Pedro N. Jiménez-Morillo is acknowledged for statistical assistance.info:eu-repo/semantics/publishedVersio