Supercritical Fluids for Higher Extraction Yields of Lipids from Archeological Ceramics

The extraction and study of organic residues from ceramics has been a subject of interest for the last 50 years in archeology and archeological science. Lipids are among the best-preserved organic substances in archeological contexts and can provide information about the diets of ancient populations as well as past environments. Here, we present a method which demonstrates significantly improved extraction of lipids from archeological pots by replacing liquid organic solvents with supercritical fluids. Optimization of the procedure using response surface methodology (RSM) approach showed that, on our system, optimal conditions for supercritical extraction of lipids from synthetic fired clay ceramics could be achieved using carbon dioxide with 16 vol % of cosolvent EtOH–H2O (95:5 v/v) in 90 min at a flow rate of 2.3 mL/min, for a pressure of 30 MPa and a temperature of 50 °C. For all reference and archeological samples included in this study, lipid yields obtained by supercritical fluid extraction under these optimal conditions were systematically higher than by conventional solvent extraction. This study also highlighted a variability of the ratio of unsaturated versus saturated fatty acids depending on the extraction method. This can have important implications in the identification of the residue(s). The increased extraction efficiency provided by supercritical fluids, as well as their minimally destructive nature, enable new and refined approaches to residue analysis and dating of archeological ceramics

Innovation in wastewater near-source tracking for rapid identification of COVID-19 in schools Comment

COVID-19 is one of the biggest global public health challenges of the century with almost 42 million cases and more than a million deaths to date. Until a COVID-19 vaccine or effective pharmaceutical intervention is developed, alternative tools for the rapid identification, containment, and mitigation of the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are of paramount importance for managing community transmission. Within this context, school closure has been one of the strategies implemented to reduce spread at local and national levels. [...

The impact of farming on prehistoric culinary practices throughout Northern Europe

To investigate changes in culinary practices associated with the arrival of farming, we analysed the organic residues of over 1,000 pottery vessels from hunter-gatherer-fisher and early agricultural sites across Northern Europe from the Lower Rhine Basin to the Northeastern Baltic. Here, pottery was widely used by hunter-gatherer-fishers prior to the introduction of domesticated animals and plants. Overall, there was surprising continuity in the way that hunter-gatherer-fishers and farmers used pottery. Both aquatic products and wild plants remained prevalent, a pattern repeated consistently across the study area. We argue that the rapid adaptation of farming communities to exploit coastal and lagoonal resources facilitated their northerly expansion, and in some cases, hunting, gathering, and fishing became the most dominant subsistence strategy. Nevertheless, dairy products frequently appear in pottery associated with the earliest farming groups often mixed with wild plants and fish. Interestingly, we also find compelling evidence of dairy products in hunter-gatherer-fisher Ertebølle pottery, which predates the arrival of domesticated animals. We propose that Ertebølle hunter-gatherer-fishers frequently acquired dairy products through exchange with adjacent farming communities prior to the transition. The continuity observed in pottery use across the transition to farming contrasts with the analysis of human remains which shows substantial demographic change through ancient DNA and, in some cases, a reduction in marine consumption through stable isotope analysis. We postulate that farmers acquired the knowledge and skills they needed to succeed from local hunter-gatherer-fishers but without substantial admixture

Ancient lipids document continuity in the use of early hunter-gatherer pottery through 9,000 years of Japanese prehistory

The earliest pots in the world are from East Asia and date to the Late Pleistocene. However, ceramic vessels were only produced in large numbers during the warmer and more stable climatic conditions of the Holocene. It has long been assumed that the expansion of pottery was linked with increased sedentism and exploitation of new resources that became available with the ameliorated climate, but this hypothesis has never been tested. Through chemical analysis of their contents, we herein investigate the use of pottery across an exceptionally long 9,000-y sequence from the Jōmon site of Torihama inwestern Japan, intermittently occupied from the Late Pleistocene to the mid-Holocene. Molecular and isotopic analyses of lipids from 143 vessels provides clear evidence that pottery across this sequence was predominantly used for cooking marine and freshwater resources, with evidence for diversification in the range of aquatic products processed during the Holocene. Conversely, there is little indication that ruminant animals or plants were processed in pottery, although it is evident from the faunal and macrobotanical remains that these foods were heavily exploited. Supported by other residue analysis data from Japan, our results show that the link between pottery and fishing was established in the Late Paleolithic and lasted well into the Holocene, despite environmental and socio-economic change. Cooking aquatic products in pottery represents an enduring social aspect of East Asian hunter-gatherers, a tradition based on a dependable technology for exploiting a sustainable resource in an uncertain and changing world

Chemical evidence for the persistence of wine production and trade in Early Medieval Islamic Sicily

As a high-value luxury commodity, wine has been transported across the Mediterranean since the Bronze Age. The wine trade was potentially disrupted during political and religious change brought about by Islamization in the Early Medieval period; wine consumption is prohibited in Islamic scripture. Utilizing a quantitative criterion based on the relative amounts of two fruit acids in transport amphorae, we show that wine was exported from Sicily beyond the arrival of Islam in the ninth century, including to Christian regions of the central Mediterranean. This finding is significant for understanding how regime change affected trade in the Middle Ages. We also outline a robust analytical approach for detecting wine in archaeological ceramics that will be useful elucidating viniculture more broadly.Although wine was unquestionably one of the most important commodities traded in the Mediterranean during the Roman Empire, less is known about wine commerce after its fall and whether the trade continued in regions under Islamic control. To investigate, here we undertook systematic analysis of grapevine products in archaeological ceramics, encompassing the chemical analysis of 109 transport amphorae from the fifth to the eleventh centuries, as well as numerous control samples. By quantifying tartaric acid in relation to malic acid, we were able to distinguish grapevines from other fruit-based products with a high degree of confidence. Using these quantitative criteria, we show beyond doubt that wine continued to be traded through Sicily during the Islamic period. Wine was supplied locally within Sicily but also exported from Palermo to ports under Christian control. Such direct evidence supports the notion that Sicilian merchants continued to capitalize on profitable Mediterranean trade networks during the Islamic period, including the trade in products prohibited by the Islamic hadiths, and that the relationship between wine and the rise of Islam was far from straightforward.All study data are included in the article and/or SI Appendix

Investigating the formation and diagnostic value of ω-(o-alkylphenyl)alkanoic acids in ancient pottery

Long chain ω‐(o‐alkylphenyl)alkanoic acids (APAAs) derived from the heating of unsaturated fatty acids have been widely used for the identification of aquatic products in archaeological ceramic vessels. To date, little attention has been paid to the diagnostic potential of shorter chain (<C20) APAAs, despite their frequent occurrence. Here, a range of laboratory and field experiments and analyses of archaeological samples were undertaken to investigate whether APAAs could be used to further differentiate different commodities. The results of this study provide new insights regarding conditions for the formation of APAAs and enable us to propose novel criteria to distinguish different natural products

Wastewater monitoring for detection of public health markers during the COVID-19 pandemic: Near-source monitoring of schools in England over an academic year

BACKGROUND: Schools are high-risk settings for infectious disease transmission. Wastewater monitoring for infectious diseases has been used to identify and mitigate outbreaks in many near-source settings during the COVID-19 pandemic, including universities and hospitals but less is known about the technology when applied for school health protection. This study aimed to implement a wastewater surveillance system to detect SARS-CoV-2 and other public health markers from wastewater in schools in England. METHODS: A total of 855 wastewater samples were collected from 16 schools (10 primary, 5 secondary and 1 post-16 and further education) over 10 months of school term time. Wastewater was analysed for SARS-CoV-2 genomic copies of N1 and E genes by RT-qPCR. A subset of wastewater samples was sent for genomic sequencing, enabling determination of the presence of SARS-CoV-2 and emergence of variant(s) contributing to COVID-19 infections within schools. In total, >280 microbial pathogens and >1200 AMR genes were screened using RT-qPCR and metagenomics to consider the utility of these additional targets to further inform on health threats within the schools. RESULTS: We report on wastewater-based surveillance for COVID-19 within English primary, secondary and further education schools over a full academic year (October 2020 to July 2021). The highest positivity rate (80.4%) was observed in the week commencing 30th November 2020 during the emergence of the Alpha variant, indicating most schools contained people who were shedding the virus. There was high SARS-CoV-2 amplicon concentration (up to 9.2x106 GC/L) detected over the summer term (8th June - 6th July 2021) during Delta variant prevalence. The summer increase of SARS-CoV-2 in school wastewater was reflected in age-specific clinical COVID-19 cases. Alpha variant and Delta variant were identified in the wastewater by sequencing of samples collected from December to March and June to July, respectively. Lead/lag analysis between SARS-CoV-2 concentrations in school and WWTP data sets show a maximum correlation between the two-time series when school data are lagged by two weeks. Furthermore, wastewater sample enrichment coupled with metagenomic sequencing and rapid informatics enabled the detection of other clinically relevant viral and bacterial pathogens and AMR. CONCLUSIONS: Passive wastewater monitoring surveillance in schools can identify cases of COVID-19. Samples can be sequenced to monitor for emerging and current variants of concern at the resolution of school catchments. Wastewater based monitoring for SARS-CoV-2 is a useful tool for SARS-CoV-2 passive surveillance and could be applied for case identification and containment, and mitigation in schools and other congregate settings with high risks of transmission. Wastewater monitoring enables public health authorities to develop targeted prevention and education programmes for hygiene measures within undertested communities across a broad range of use cases

New insights into early medieval Islamic cuisine : Organic residue analysis of pottery from rural and urban Sicily

Sicily, during the 9th-12th century AD, thrived politically, economically, and culturally under Islamic political rule and the capital of Palermo stood as a cultural and political centre in the Mediterranean Islamic world. However, to what extent the lifeways of the people that experienced these regimes were impacted during this time is not well understood, particularly those from lesser studied rural contexts. This paper presents the first organic residue analysis of 134 cooking pots and other domestic containers dating to the 9th -12th century in order to gain new insights into the culinary practices during this significant period. Ceramics from three sites in the urban capital of Palermo and from the rural town of Casale San Pietro were analysed and compared. The multi-faceted organic residue analysis identified a range of commodities including animal products, vegetables, beeswax, pine and fruit products in the ceramics, with a complex mixing of resources observed in many cases, across all four sites and ceramic forms. Alongside the identification of commodities and how they were combined, new light has been shed on the patterning of resource use between these sites. The identification of dairy products in calcite wares from the rural site of Casale San Pietro and the absence of dairy in ceramics from the urban centre of Palermo presents interesting questions regarding the role of rural sites in food consumption and production in Islamic Sicily. This is the first time organic residue analysis of ceramics has been used to explore foodways in a medieval multi-faith society and offers new pathways to the understanding of pottery use and resources that were prepared, consumed and combined, reflecting cuisine in different socio-economic environments within the pluralistic population of medieval Sicily

Sicily in transition : new research on early medieval Sicily, 2017-2018

Il testo che segue riguarda la nostra ricerca archeologica sulla Sicilia bizantina, islamica e normanno-sveva e in particolare riporta le ultime scoperte a Castronovo di Sicilia, che includono il riconoscimento di una chiesa del XII-XIII secolo sul Monte Kassar, la continuazione dello scavo a Casale San Pietro e una sintesi delle nuove ricognizioni nelle sue vicinanze. Quest’ultimo sito rimane il focus principale del Progetto ERC sictransit, ma in questa sede diamo anche conto dei primi risultati di un’indagine più ampia, che include una grossa quantità di reperti che provengono da tutta la Sicilia da siti scavati in precedenza (Fig 1). Questi reperti consistino in ceramiche, metalli e vetri assieme a resti umani, animali e vegetali, che vengono analizzati nei laboratori delle università partner del progetto: York, Roma e Lecce. I principali metodi scientifici applicati sono: analisi tipologiche, petrografiche e del contenuto organico delle ceramiche da cucina e da trasporto; degli isotopi stabili e del DNA antico sui resti umani e animali per determinare la dieta e l’ascendenza genetica; infine la identificazione tassonomica e la caratterizzazione isotopica degli insiemi di resti botanici per comprendere le loro relazioni con il clima e con le diverse fasi storiche. Sictransit combina quindi ricerche archeologiche, bioarcheologiche e biomolecolari in un unico progetto integrato. Gli obiettivi attesi sono stati suddivisi, per comodità e chiarezza, in tre principali aree di studio, vale a dire: agricoltura (e cibo), scambi e demografia. Infine concludiamo con una valutazione della ricerca svolta sul campo e delle prospettive di indagine dei tre laboratori

Parallel worlds and mixed economies : multi-proxy analysis reveals complex subsistence systems at the dawn of early farming in the northeast Baltic

The transition from foraging to farming was a key turning point in ancient socio-economies. Yet, the complexities and regional variations of this transformation are still poorly understood. This multi-proxy study provides a new understanding of the introduction and spread of early farming, challenging the notions of hierarchical economies. The most extensive biological and biomolecular dietary overview, combining zooarchaeological, archaeobotanical, dietary stable isotope and pottery lipid residue analyses is presented, to unravel the nature and extent of early farming in the 3rd millennium cal BCE in the northeast Baltic. Farming was introduced by incoming Corded Ware cultural groups (CWC), but some dietary segregation existed within these communities, with some having more access to domesticates, others incorporating more wild resources into their diet. The CWC groups coexisted in parallel with local hunter–fisher–gatherers (HFG) without any indication of the adoption of domesticates. There was no transition from foraging to farming in the 3rd millennium cal BCE in the NE Baltic. Instead, we see a complex system of parallel worlds with local HFGs continuing forager lifeways, and incoming farmers practising mixed economies, with the continuation of these subsistence strategies for at least a millennium after the first encounter with domesticated animals