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The increasing plastic pollution of the world’s oceans represents a serious threat to marine ecosystems and has become a well-known topic garnering growing public attention. The global input of plastic waste into the oceans is estimated to be approximately 10 million tons per year and predicted to rise by one order of magnitude by 2025. More than 90% of the plastic that enters the oceans is thought to end up on the seafloor, and seafloor sediment samples show that plastics are concentrated in confined morphologies and sedimentary environments such as submarine canyons. These canyons are occasionally flushed by powerful gravity-driven sediment flows called turbidity currents, which transport vast volumes of sediment to the deep sea and deposit sediment in deep-sea fans. As such, turbidity currents may also transport plastics present in the canyon and bury plastics in deep-sea fans. These fans may therefore act as sinks for seafloor plastics. Here we present a comprehensive dataset showing the spatial distribution of microplastics in seafloor sediments from the Congo Canyon, offshore West Africa. Multicores taken from 16 locations along the canyon, sampled different sedimentary sub-environments including the canyon thalweg, canyon terraces, and distal lobe. Microplastics were extracted from the sediments by density separation and the polymer type, size, and shape of all individual microplastic particles were analysed using laser-direct infrared-spectroscopy (LDIR). Microplastic number concentrations in the sediments of the distal lobe are significantly higher than in the canyon, indicating that the Congo Canyon system is a highly efficient conduit for microplastic transport to the deep sea. Moreover, microplastic concentrations of >20,000 particles per kg of dry sediment were recorded in the lobe, which represent some of the highest ever recorded microplastic number concentrations in seafloor sediments. This shows that deep-sea fans can serve as hotspots and potential terminal sinks for seafloor microplastics.

A patient at the fifth stage of chronic kidney disease usually needs dialysis or transplantation. The adequacy of dialysis can be assessed by the dimensionless parameter Kt/V , which depends on the concentration of urea in the blood. Kt/V is usually measured before and after treatment, or by an indirect measurement of dialysis fluid conductivity. For the real-time monitoring of the urea concentration during dialysis, this paper proposes a disposable biosensor that combines a pH sensitive reduced graphene oxide layer functionalized with 4-amino benzoic acid and urease. Urease is immobilized on reduced graphene oxide and catalyzes the hydrolysis of urea into carbon dioxide and ammonia. This catalysis increases the pH value locally and elicits a sensor response. Urea concentration was assessed in the plasma of five dialyzed patients using a potentiometric measurement. The response time was 120 s and the error was 6 ± 3% compared with standard clinical laboratory analysis.

This paper presents a study on the pyrolytic behavior of mixtures of lignocellulosic biomass with hydrocarbon plastics using analytical pyrolysis-GC/MS. Semi-quantitative analysis using chromatographic peak areas was used to investigate the composition of the pyrolysis oils and to highlight the occurrence of synergistic effects. A new method is also proposed to estimate the elemental composition of the pyrolysis oil based on the peak areas and brute formulas of the pyrolysis products. The results indicate that synergistic effects during co-pyrolysis favor secondary pyrolysis of holocellulose and polystyrene oligomers, and hinder radical chain-scission of polyethylene chains. H/C and O/C values of the pyrolysis oils were improved by the addition of plastic, indicating a decrease in the content of oxygenated pyrolysis products. The best performances were observed for the mixture containing 70% fir wood and 30% polyethylene, in which synergistic effects led to both an increase of H/C and a decrease of O/C.

StAr project - Development of Storage and assessment methods suited for organic archaeological artefacts – started in 2020 within the framework of Joint Programming Initiative on Cultural Heritage and Global Change (JPI-CH) Conservation, Protection and Use. The project arises from the need for chemical-physical stabilization strategies of archaeological finds (mainly wood and leather), for long time (up to several months) in the waterlogged state, i.e., under pre-treatment conditions, without compromising the archaeological and scientific evidences they contain. Several methods of controlling storage conditions will be tested on archaeological wooden and leather objects. The experimentations will entail a systematic chemical analysis and monitoring of the organic materials before, during and after storage in different conditions, both in laboratory and on-field at the Biskupin archaeological excavation site in Poland.

Up to 13 million tons of plastic waste are estimated to enter the oceans every year. A generally accepted picture based on an increasing number of environmental studies suggests that the largest fraction of it consists or is rapidly degraded into microplastics (MPs). Most of the analytical studies focused on MPs are based on the detection and identification of the polymers. On the other hand, plastic debris in the environment undergo chemical (mainly photoxidative) and physical degradation processes leading not only to fragmentation but also to the formation of leachable, soluble and/or volatile degradation products that are released in the environment. The formation of such low molecular weight species is generally neglected in the studies on MPs even if these compounds, released in the environment from the plastics debris, may pose even higher risks for the environment and for the biota than the MPs particles themselves, risks that are far from being understood and assessed. In this study we performed the analysis of reference MPs - polymer micropowders obtained by grinding a set of five polymer types down to final size in the 857-509 μm range, namely high- and low-density polyethylene (HDPE and LDPE, respectively), polystyrene (PS), polypropylene (PP), and polyethylene terephthalate (PET). The reference MPs were artificially aged in a Solar-Box and their degradation products were analyzed to investigate their degradation processes. In particular, a systematic and thorough characterization of the aged (photo-oxidized) MPs and of their low molecular weight and/or highly oxidized fraction extractable in polar organic solvents was performed. For this purpose, the artificially aged MPs were subjected to selective extraction with organic solvent that are non-solvents for the virgin polymers, targeting selective recovery of the low molecular weight fractions generated during the artificial aging. Analysis of both the extractable fractions and the residues was carried out by a multi-technique approach combining evolved gas analysis-mass spectrometry (EGA-MS) and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). Up to 18 wt% of newly extractable, low molecular weight fraction was recovered from the photo-aged MPs, depending on the polymer type. The results highlight the need for more extensive studies about the potential harmfulness of the oxidation products (molecular and oxidized oligomeric species) that may leach out from plastic debris during their permanence in the environment.

In the last years, the price of several collectible comic books reached the record value of millions of dollars. Since the value of collectible comic books is strictly related to their state of preservation, specialized rating agencies certificate their quality and condition, and for the same reason comics books are commonly encapsulated in sealed containers or bags for preservation and protection. Nonetheless, recent studies regarding micro-climate frames for the exhibition or storage of artworks as paintings suggest that the storage of any composite object made of organic materials in a sealed environment could lead to the presence of a significant concentration of volatile organic compounds (VOCs) in the enclosed micro-climate, that can be related to unexpected degradation pathways, or to an increase in the ageing rate of materials. In this study, we characterized the volatile organic compounds (VOCs) emitted by comic books stored in archival bags for the first time in the literature. In particular, we analyzed the VOCs emitted by comic books printed in the last six years by the same publisher. We applied solid phase micro extraction (SPME) to characterize the VOCs profile inside archival bags containing comic books by gas chromatography/mass spectrometry (GC/MS). The semi-quantitative data obtained on more than 60 individual VOCs were elaborated by principal component analysis (PCA) allowing us to highlight a variation in the profiles of the emissions of the series of comics books printed from 2012 to 2018 and stored in sealed archival bags immediately after the purchase. Select ion flow tube mass spectrometry (SIFT-MS) was also used to obtain quantitative results in real time, as an alternative to the SPME sampling step. This study represents the first reported application of SIFT-MS in heritage science. The study contributed to identify VOC profiles and molecular markers that can be used to study the emission of comic books in sealed bags, and can ultimately be correlated to the degradation processes of the materials used in their production.

Microplastics are the particulate plastic debris found almost everywhere as environmental contaminants. They are not chemically stable persistent pollutants, but reactive materials. In fact, synthetic polymers exposed to the environment undergo chemical and physical degradation processes which lead not only to mechanical but also molecular fragmentation, releasing compounds that are potentially harmful for the environment and human health. We carried out accelerated photo-oxidative ageing of four reference microplastics (low- and high-density polyethylene, polypropylene, and polystyrene) directly in artificial seawater. We then made a characterization at the molecular level along with a quantification of the chemical species leached into water. Gas chromatography/mass spectrometry analyses performed after selective extraction and derivatization enabled us to identify more than 60 different compounds. Analysis of the leachates from the three polyolefins revealed that the main degradation products were mono- and dicarboxylic acids, along with linear and branched hydroxy acids. The highest amount of leached degradation species was observed for polystyrene, with benzoic acid and phenol derivatives as the most abundant, along with oligomeric styrene derivatives. The results from reference microplastics were then compared with those obtained by analyzing leachates in artificial seawater from aged plastic debris collected in a natural environment. The differences observed between the reference and the environmental plastic leachates mainly concerned the relative abundances of the chemical species detected, with the environmental samples showing higher amounts of dicarboxylic acids and oxidized species.

Co-pyrolysis of biomass and plastics gives rise to synergistic effects that can improve the properties of the resulting bio-oil. In this paper, the co-pyrolysis of lignocellulose (softwoods and hardwoods) and plastic (polyethylene and polystyrene) mixtures at different ratios was investigated by evolved gas analysis-mass spectrometry (EGA-MS). Through the extraction of specific sets of m/z values, we were able to build component-specific thermograms representative of each component of the mixtures. Such thermograms were used to evaluate the presence of synergistic effects by the comparison with the theoretical thermograms. The shift of the peak temperatures and the differences between the integrated area of the two thermograms showed that both biomass and plastic influence the pyrolytic behaviour of the other component. Finally, the KAS model-free isoconversional method was used on component-specific thermograms to determine apparent activation energies of the biomass and plastic fractions.

Modern humans expanded into Eurasia more than 40,000 years ago following their dispersal out of Africa. These Eurasians carried ~2–3% Neanderthal ancestry in their genomes, originating from admixture with Neanderthals that took place sometime between 50,000 and 60,000 years ago, probably in the Middle East. In Europe, the modern human expansion preceded the disappearance of Neanderthals from the fossil record by 3,000–5,000 years. The genetic makeup of the first Europeans who colonized the continent more than 40,000 years ago remains poorly understood since few specimens have been studied. Here, we analyse a genome generated from the skull of a female individual from Zlatý kůň, Czechia. We found that she belonged to a population that appears to have contributed genetically neither to later Europeans nor to Asians. Her genome carries ~3% Neanderthal ancestry, similar to those of other Upper Palaeolithic hunter-gatherers. However, the lengths of the Neanderthal segments are longer than those observed in the currently oldest modern human genome of the ~45,000-year-old Ust’-Ishim individual from Siberia, suggesting that this individual from Zlatý kůň is one of the earliest Eurasian inhabitants following the expansion out of Africa., The authors present the genome sequence of a >45,000-year-old female Homo sapiens individual from the site of Zlatý kůň, Czechia. Although radiometric dating of the human remains was inconclusive, the authors were able to use molecular methods to demonstrate that she was probably among the earliest Eurasian inhabitants following expansion out of Africa.

Pollution from microplastics (MPs) needs to be evaluated by deploying reliable analytical techniques that provide qualitative and quantitative data on the extent of contamination in the various environmental matrices. Solvent extraction of MPs followed by pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) provides data that not only regard the soluble plastics, but also the organic additives contained in MPs and the low-molecular weight degradation products of insoluble plastics. In this study, the potential of microwave-assisted solvent extraction and double-shot Py-GC-MS was investigated in order to obtain quali-quantitative information on polystyrene and on phthalate plasticizers in environmental samples. The method was validated and provided recoveries higher than 96 %, and detection limits lower than 1 ng and 1 μg for phthalates and polystyrene, respectively. We used the method to analyze samples of sand collected from a shoreline in Tuscany (central Italy) and thereby determine the content of phthalates and polystyrene at different depths and distances from the coastline. Qualitative data were also obtained regarding the presence of oxidation products derived from polyethylene and polypropylene. The different contents of plasticizers, plastics, and degradation products in the investigated samples are discussed in relation to how environmental agents affect the leaching and degradation processes of the polymers.

The scientific analysis of mummified individuals can reveal important details on the way people lived and died in the past. Palaeoproteomic approaches are theoretically suitable for obtaining information on the extent of tissue preservation, on the use of protein-based substances for embalming and/or restoration, as well as for characterising the microbiota from both the individual and the environment. However, these analyses usually require the destruction of a sample of tissue, a practice which is (obviously) discouraged by most museums. Unfortunately, this means that in-depth studies, for example by taking multiple samples from each individual, are seldom feasible. Here we show that a non-invasive sampling technique, based on mixed-bed chromatographic media embedded on ethylene vinyl acetate membranes (EVA), which had previously been used exclusively on historical material, was successful in extracting ancient proteins from the surface of Egyptian mummies. We tested the method on a decontextualised fragment of skin and assessed the endogeneity of its metaproteome by comparison with a procedural blank. Furthermore, we retrieved and authenticated sequences of human collagen and keratin, as well as potential bacterial/fungal biodeteriogens, from the mummy of a young woman (Supp. 16747 of the Museum of Anthropology and Ethnography of the University of Turin) who lived and died during the Old Kingdom of Egypt.

Peru Balsam, a resinous substance derived from Myroxylon balsamum var. pereirae, has historically been used as a topical ointment for various skin conditions such as scabies, poorly healing wounds, eczema, and haemorrhoids. The ingredients responsible for these properties are not fully elucidated. We investigated the chemical composition of two Peru Balsam samples, one historical and one modern, using gas chromatography/mass spectrometry to identify the active ingredients responsible for its pharmaceutical properties. Both Peru Balsam specimens investigated had similar compositions, showing the stability of the substance. Components identified are effective against scabies, exhibit antimicrobial activity and aid skin penetration. These properties are consistent with historical uses of Peru Balsam. Several ingredients are also known allergens. This study, combining chemical information with scientific literature related to pharmaceutical properties of natural substances, represents a breakthrough in the elucidation of active ingredients in Peru Balsam.

In the present work, evolved gas analysis-mass spectrometry (EGA-MS) and analytical pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS) were used to characterize both the volatile and non-volatile fractions of six commercially available spices. Analysis of spices is usually performed through the study of their headspace composition by solid phase microextraction (SPME). In this new approach, EGA-MS was used to establish thermal degradation regions, and Py-GC/MS was used to obtain compositional information on each region separately using double-shot pyrolysis. This study demonstrates that EGA-MS and Py-GC/MS provide the same advantages of solid-phase micro extraction and increase the range of detectable products by performing high-temperature desorption and degradation of the non-volatile fraction of spices. Our approach provided both qualitative and semi-quantitative data that could be used in the future to improve authentication studies by considering the results not only of headspace composition, but also on the pyrolytic behavior of the lignocellulosic matrix.

Microplastics pollution is an acknowledged global issue, and new strategies are required to meet the increasing demand of standardized, fast and reliable measurements. Analytical pyrolysis coupled to gas chromatography and mass spectrometry (Py-GC/MS) is a promising technique to obtain qualitative and quantitative data on microplastics mixtures through the selection of a set of characteristic pyrolysis products for each polymer. However, this data processing method is time-consuming, and no automated algorithms are currently available. In the present work, a new method for the qualitative analysis of eleven types of synthetic polymers was developed, automated and implemented in the F-Search software, with the aim of proposing a standardized procedure for data processing in Py-GC/MS analysis of plastics mixtures. The method improves on the current literature, and is based on the generation of summated mass spectra (SMS) for each polymer, obtained by extracting specific m/z and retention index coordinates corresponding to characteristic pyrolysis products. The identification of a polymer is performed by comparing its SMS with those of a built-in library. After validation, the algorithm was tested on a reference sample containing all eleven investigated polymers. The algorithm provided relative standard deviations around 10%, and the results were used to estimate the lowest amount of polymer detectable in a sample, which was found lower than 1 μg for most polymers. The performance of the algorithm was also evaluated on a real sample from ocean water trawling, providing positive results for four different polymers. The performances of the algorithm are discussed, and possible future developments are outlined.

The pyrolysis reactions of hardwood and softwood were investigated using evolved gas analysis and mass spectrometry (EGA-MS) and by treating the experimental data with isoconversional methods to obtain kinetic information. Mass spectrometric detection allowed the identification of the pyrolysis products to be performed and component-specific thermograms were obtained by the extraction of appropriate m/z values without the need of peak-fitting. Finally, isoconversional methods, both an integral and a differential method, were used on compound-specific thermograms to calculate apparent activation energies of the carbohydrate and lignin fractions separately. The results showed that the two isoconversional methods provide comparable results, and that there are significant differences between the activation energies of the holocellulose and lignin fractions. This work shows that EGA-MS can provide reliable kinetic data for multi-component samples without the need of chemical pre-treatments or signal deconvolution.

The archaeological site of Biskupin (Poland) is a prehistoric settlement dating to the 8th century BC, situated on a marshy island. Excavations started in 1934 and a considerable number of wooden artifacts were found in the lake water. Unfortunately, during many years of archaeological excavations, wooden remains deposited in the trenches were exposed to degradation and underwent considerable decomposition. Among the main causes of wood degradation, fungi and bacteria were the most destructive ones. The chemical effects induced by fungi and bacteria on wood are not well-known or studied. Here we present the investigation of a set of pine wood samples (Pinus sylvestris) buried in the Biskupin site, with the aim of reproducing the burial conditions of the original archaeological wood. Two monitoring stations (wet peat and lake water) were chosen and the samples were then removed from these burial environments after four and ten years. After removal, the samples were exposed to laboratory-controlled attack by the brown rot fungus Coniophora puteana. The final aim was to evaluate the effects of fungal activity on the wood substrates with different degrees of natural degradation. The study is part of an experiment designed to evaluate the short-term effects of the in situ preservation strategy adopted for the Biskupin archaeological woods. Various techniques were used to assess the physical and chemical degradation of the wood. The morphological changes induced by the exposure to the burial environment and by the action of the fungi were investigated using scanning electron microscopy (SEM). The chemical state of the wood was evaluated by using infrared spectroscopy (FTIR), analytical pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) and XRD spectroscopy. Fungal action caused the depletion of polysaccharides resulting in mass loss and the FTIR spectra of the wood samples highlighted that cellulose was more degraded with respect to hemicelluloses. This trend correlated with an increase in the relative abundance of furans, which are among the main pyrolysis products of polysaccharides. Fungal attack also induced oxidation of lignin and an increase in the crystallinity index of cellulose, which points towards a preferential metabolisation of amorphous cellulose. The overall results highlighted that the burial in these wet environments caused changes mostly in the hemicelluloses, whereas the fungal attack was mainly directed to cellulose degradation.

Up to now, on the industrial scale, the acid-catalysed hydrothermal conversion of lignocellulosic biomass has been targeted to the production of levulinic acid (LA), while the lignin fate has been neglected, and its use has been limited at most to the energy recovery. Now, an integrated investigation of the hydrothermal process for the synthesis of LA starting from giant reed (Arundo Donax L.) was studied taking into account the lignin phenol derivatives present in the liquid phase and in the solid hydrochar. The analysis of the hydrochar was carried out adopting coupled pyrolysis techniques, e.g. Py-GC/MS, TGA/FTIR, and EGA-MS, paying a special attention to the contribution of the evolved simple phenolics. The hydrochar washing fractions were analyzed for the total phenolic content (TPC) and antioxidant activity (AA), adopting TEAC, FRAP, and DPPH standard essays, comparing the antioxidant activities with those deriving from the starting LA-rich mother liquor. Two washing cycles allowed the complete recovery of the phenolic compounds of interest, leached from the porous hydrochar. Also the starting LA-rich liquor was of great interest for the same purpose, having the highest content of these compounds, which must be necessarily removed for the production of the commercial pure LA. Promising antioxidant properties were ascertained for the mother liquor and the hydrochar washings, obtaining good linear correlations between total phenolic compounds (TPC) and antioxidant capacity (TEAC, FRAP, and DPPH). This multi-valorisation approach contributes to improving the sustainability of the entire LA process and shifts the attention towards the antioxidants, new niche bioproducts of great interest, which add significant economic value to the overall Biorefinery of the lignocellulosic biomass.

Analytical pyrolysis is a powerful tool to study the thermal behaviour of organic compounds, but relatively little information is available on the pyrolysis of amines, especially when bound to inorganic systems. In this study, we analysed aliphatic amines (propylamine, dipropylamine, tripropylamine, and tert-butylamine), both as pure compounds and bound to titania nanoparticles, using multi-shot analytical pyrolysis-gas chromatography coupled to mass spectrometry (Py-GC–MS) with a liquid nitrogen cryo-trap system. Desorption of amines was observed at 260 °C, while pyrolysis reactions were mostly observed at 600 °C. Pure amines underwent intermolecular reactions, generating heavier nitrogen-containing compounds. Conversely, amines bound to titania nanoparticles underwent loss of ammonia and hydrogen, and both inter- and intramolecular couplings generate unsaturated hydrocarbons and aromatics. Differences in the pyrolysis mechanisms were attributed to the catalytic effect of the nanoparticles. The present work provides fundamental information on the pyrolytic behaviour of aliphatic amines and on the catalytic effect of titania nanoparticles.

Environmental pollution by microplastics (MPs) has attracted much attention due to possible risks of MPs to human health, and fast and reliable analytical methods are required for identification and quantification of MPs in various matrices. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) has advantageous characteristics in that both identification and mass quantification can be easily done by chromatographic separation in combination with mass spectral analysis. Environmental MP samples usually contain several types of polymers and the pyrolysis of mixed polymer particles may cause a secondary reaction between pyrolyzates from different polymers. In this study, effect of the usage of calcium carbonate (CaCO3) as a catalyst on pyrolytic behavior of polymers was examined to obtain catalytic conversion of reactive pyrolyzates to stable compounds. CaCO3 was also utilized as a diluent for insoluble PE and PP powders to assure weighing easiness by forming a homogenous mixture. First, a reference material was prepared to make calibration curves by mixing twelve different types of standard polymers, selected to reflect common polymers in the global production. Identification and quantification of polymers in mixed polymer samples were validated by using model polymer mixtures, after storing Py-GC/MS data of twelve polymers with a given sample amount in a software named as F-Search MPs. Results exceeding the limit of quantitation combined with the high probability of a library match as confirmed by the software, provided assurance of the presence of the identified polymer in the model polymer mixtures. The quantitated values for the model polymer mixtures were compared with the compounded amount. The recovery varied depending on the polymer type, and especially short recovery (ca. 60–70 %) was recognized for PC in the sample from Solution A (SA) and excess recovery (ca. 175 %) for PET in the sample from Solution B (SB). Finally, the developed method was applied to the analysis of ground mixtures of isolated environmental MP particle samples and quick identification and quantification of each polymer in the MP samples were attained.

UV degradation of wood is an important phenomenon that entails loss of aesthetic and mechanic properties. The changes are usually studied with artificial ageing followed by spectroscopy, and focus on colour changes. Analytical pyrolysis coupled with gas chromatography-mass spectrometry (Py-GC/MS) and evolved gas analysis-mass spectrometry (EGA-MS) are powerful tools for wood characterisation, but the change in pyrolytic behaviour of wood after UV irradiation is not well documented. In this work, a new instrumental setup was used to perform UV irradiation on line with EGA-MS and Py-GC/MS with in situ derivatisation of fir and chestnut wood. The effect of UV exposure was evaluated in terms of thermal stability and composition of the pyrolysate. TThe results showed that UV degradation of the samples was mainly related to the lignin fraction, and significant differences were observed between the two species. Fir wood, showed extensive degradation after 4 hours of irradiation, while chestnut wood, showed very small changes. Qualitative comparison of the EGA-MS profiles and semi-quantitative analyses of the composition of the pyrolysates revealed that these techniques could be used as a fast monitoring tool to assess the UV degradation of wood.

Natural tannins from various plants have been used throughout human history in textile dyeing, often as mordant dyes. The ageing behavior of these dyes is a challenge in conservation science, requiring a thorough knowledge of the textile&ndash, mordant-dye system. In this work, we analyzed reference wool yarns dyed with natural tannins from oak gallnuts, walnut (Juglans regia), and catechu (Acacia catechu), after artificial ageing. To gain insights on the composition of the dyestuffs and on how they aged, an analytical procedure based on extraction with Na2EDTA/DMF (ethylenediaminetetraacetic acid/dimethylformamide) and high-performance liquid chromatography (HPLC) analysis using high-resolution mass spectrometry detection was used. Since conventional reversed-phase (RP) columns usually show poor retention efficiency of highly polar compounds such as tannins, an RP-amide embedded polar group stationary phase was used to achieve optimal retention of the most polar compounds. Tannins from oak gallnuts showed little degradation after ageing, while a significant increase in the content of hydroxybenzoic acids was observed for tannins from walnut and catechu. Finally, the analytical procedure was applied to characterize the tannin dyes in historical tapestries from the 15th to 16th century, and the results were discussed in comparison with the reference yarns.

A novel analytical procedure based on solid-phase extraction, HPLC-DAD and HPLC-MS 2 analyses is here presented for the study of seven different monofloral honey types from Tuscany (Italy) in terms of their phenolic content. In particular, an embedded polar group RP-Amide stationary phase is employed in order to achieve the separation and quantitation of 24 different polyphenols. Extraction recoveries and dynamic linear ranges are determined, and limits of detection as low as 1 ng/g are obtained. Quantitation of the polyphenol content revealed total concentrations in the order of 10 0 –10 2 μg/g, with chestnut honeys showing the highest results. Further analyses with HPLC-MS 2 proved invaluable in the identification of unknown compounds found in the honeys. Processing of the chromatographic data via Principal component analysis divided the sample pool in three groups. Each group showed distinctive traits that can be used to distinguish some of the honey types from the others.

The pyrolytic behaviour of two oligosaccharides – cellobiose and cellohexose – was studied using reactive pyrolysis-GC/MS with in situ hexamethyldisilazane derivatisation. Pyrolysis was conducted in a sealed vessel at various times ranging from 0.2 to 60 min. Semi-quantitative calculations were carried out on integrated peak areas to obtain information on derivatisation efficiency and composition of the pyrolysate as a function of pyrolysis time. The results were compared with a previous work by us in which glucose and cellulose were studied with the same procedure. The relative areas of anhydrosugars were found to decrease with the increase of the degree of polymerisation of the substrate, while the derivatisation efficiency showed an opposite trend. The results were explained by considering the role of both the sealed environment and water molecules freed during the pyrolysis process. We hypothesised that higher amounts of water were released from glucans with low degrees of polymerization, hindering both secondary pyrolysis reactions and derivatisation efficiency. Glucans with high degrees of polymerization, on the contrary, showed high signals of secondary pyrolysis products, consistent with a lower amount of water and the formation of a liquid phase.

Olive mill wastewaters (OMWs) are important by-products of olive oil production. The wide availability and the forbidding economic costs of OMWs disposal have generated interest in their possible exploitation as a sustainable source of polyphenols. The development and optimisation of improved analytical methods for the detailed characterisation of polyphenol molecular profiles after production and during storage conditions are thus required. A new analytical method based on reverse-phase HPLC separation of polyphenols in OMWs on an embedded-polar group (EPG) stationary phase is proposed as an alternative to conventional C18 columns. The procedure was used for the quantitation of 11 polyphenols, using diode-array detection (DAD), and achieving quantitation limits equal to or lower than 0.1 µg g

Olive mill wastewaters (OMWs) are important by-products of olive oil production. The wide availability and the forbidding economic costs of OMWs disposal have generated interest in their possible exploitation as a sustainable source of polyphenols. The development and optimisation of improved analytical methods for the detailed characterisation of polyphenol molecular profiles after production and during storage conditions are thus required. A new analytical method based on reverse-phase HPLC separation of polyphenols in OMWs on an embedded-polar group (EPG) stationary phase is proposed as an alternative to conventional C18 columns. The procedure was used for the quantitation of 11 polyphenols, using diode-array detection (DAD), and achieving quantitation limits equal to or lower than 0.1 µg g−1. The same chromatographic set-up, coupled with high resolution tandem mass spectrometry (HPLC/ESI-Q-ToF), allowed us to identify hydroxytyrosyl esters of elenolic acid, whose relative abundance is proposed for monitoring the ageing of OMWs during storage.

Rapid screening techniques for lignocellulosic biomass are required for the development of efficient conversion strategies in the field of biofuels and value-added chemicals. This is particularly true for tannins, which are highly valuable in the tannery and nutraceutical industries. In the present work, we propose a quick method based on reactive pyrolysis with in situ hexamethyldisilazane (HMDS) derivatization followed by GC/MS analysis for the qualitative determination of tannins in lignocellulosic biomass. Different pyrolysis times were used to study pyrolysis mechanisms of tannins. Reference compounds belonging to hydrolysable and condensed tannins, both in monomeric and polymeric forms, were used to select specific pyrolysis products that could be used as markers. When pyrolysis time was increased, hydrolysable tannins were found to be highly thermostable, while condensed tannins showed extensive degradation. An optimal pyrolysis time was determined to reduce the number of peaks and increase the abundances of the most characteristic components. The results were applied to assess the presence of tannins in four different biomass: oak gall nuts, hazelnut cuticles, grape seeds and pomegranate bark.

The Mediterranean buckthorn, Rhamnus alaternus L., is a plant used in traditional medicine in Mediterranean countries. We aimed at characterizing its phenolic compounds and explore potential antihyperlipidemic activity of this plant. The profile of phenolic compounds in R. alaternus leaf crude methanolic extract (CME) and its liquid-liquid extraction-derived fractions were analyzed by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC/ESI-MS2). Effects of CME on: circulating lipids in rats with Triton WR-1339-induced hyperlipidemia, intracellular lipid accumulation and expression of genes of fatty acid metabolism in human hepatoma HepG2 cells, and adipogenesis in the 3T3-L1 murine adipocyte cell model were assessed. The HPLC/ESI-MS2 analytical profile revealed a total of fifteen compounds, of which eleven were identified. Oral CME administration decreased blood levels of cholesterol and triacylglycerols in hyperlipidemic rats (by 60% and 70%, respectively, at 200 mg CME/kg). In HepG2 cells, CME exposure dose-dependently decreased intracellular lipids and up-regulated gene expression of carnitine palmitoyltransferase 1 involved in fatty acid oxidation. In the 3T3-L1 model, CME favored preadipocyte proliferation and adipogenesis, pointing to positive effects on adipose tissue expandability. These results suggest novel uses of R. alaternus by showing that its leaves are rich in flavonoids and flavonoid derivatives with an antihyperlipidemic effect in vivo and in hepatic cells.

Reactive pyrolysis is a technique that provides mechanistic information by performing pyrolysis of the substrate in a sealed glass capsule at elevated temperature and pressure for relatively long time. This technique has already shown great potential for the analysis of biomass, favouring the formation of only the most thermostable compounds. In this work, both fast and reactive pyrolysis with on-line gas chromatography-mass spectrometry analysis (Py-GC/MS) are used to study fructose, inulin and Jerusalem artichoke tubers (Heliantus tuberosus). Interesting differences were found between the two systems, and became even more evident as the reaction time was increased. The most striking result was the formation of di-fructose dianhydrides (DFAs), a class of compounds with interesting biological activities. DFAs were obtained in high yields from reactive pyrolysis, but not from fast pyrolysis. Hypotheses on the pyrolysis mechanisms were made based upon the composition of the pyrolysates. This work describes for the first time the behaviour of fructans under reactive pyrolysis.

The chemical characterization of shell and cuticle from Tonda Gentile Romana hazelnut was carried out using analytical pyrolysis in the presence of hexamethyldisilazane followed by gas chromatography-mass spectrometry analysis (Py(HMDS)-GC/MS) and high-performance liquid chromatography with diode-array detection (HPLC-DAD). The aim was to acquire a comprehensive picture of the chemical composition of shell and cuticle, which are produced as wastes by hazelnut confectionery industry, in view of a suitable exploitation strategy. Such waste biomass could be a promising substrate to produce value-added chemicals and biofuels. The pyrogram of the shell fraction showed the typical pyrolysis products of a lignocellulosic matrix. The cuticle pyrogram showed intense peaks that were attributed to fatty acids. Holocellulose-to-lignin (H/L) content ratios were determined both by Py-GC/MS and by a traditional wet-chemistry method. While the H/L values obtained by the two methods were similar for the shell fraction, those of the cuticle fraction were very different. To further investigate this behaviour, HPLC-DAD analyses were carried out on ethanol extracts of the two fractions. High concentrations of catechin, epicatechin and procyanidins were found in the cuticle fraction. The presence of phenolic compounds was hypothesised to determine the overestimation of the H/L ratio in the Py-GC/MS technique. 1,3,5-trihydroxybenzene was found to be a plausible marker for the presence of polyphenolic extractives in lignocellulosic materials. Based on the results obtained from the different analysis methods, possible exploitation strategies are suggested for the two waste fractions. The high lignin and carbohydrate content of the shell fraction could be used to produce value-added chemicals, biofuels and biochars. The high extractives content of the cuticle fraction, on the other hand, makes it a possible starting material to produce pharmaceutical and nutraceutical products, as well as cosmetic emulsions.