Pinaceae Pine Resins (Black Pine, Shore Pine, Rosin, and Baltic Amber) as Natural Dielectrics for Low Operating Voltage, Hysteresis-Free, Organic Field Effect Transistors.

Four pinaceae pine resins analyzed in this study: black pine, shore pine, Baltic amber, and rosin demonstrate excellent dielectric properties, outstanding film forming, and ease of processability from ethyl alcohol solutions. Their trap-free nature allows fabrication of virtually hysteresis-free organic field effect transistors operating in a low voltage window with excellent stability under bias stress. Such green constituents represent an excellent choice of materials for applications targeting biocompatibility and biodegradability of electronics and sensors, within the overall effort of sustainable electronics development and environmental friendliness.

Native lignin extraction from soft- and hardwood by green and benign sub/supercritical fluid extraction methodologies.

Lignin constitutes an impressive resource of high-value low molecular weight compounds. However, robust methods for isolation of the extractable fraction from lignocellulose are yet to be established. In this study, supercritical fluid extraction (SFE) and CO2-expanded liquid extraction (CXLE) were employed to extract lignin from softwood and hardwood chips. Ethanol, acetone, and ethyl lactate were investigated as green organic co-solvents in the extractions. Additionally, the effects of temperature, CO2 percentage and the water content of the co-solvent were investigated using a design of experiment approach employing full factorial designs. Ethyl lactate and acetone provided the highest gravimetric yields. The water content in the extraction mixture had the main impact on the amount of extractable lignin monomers (LMs) and lignin oligomers (LOs) while the type of organic solvent was of minor importance. The most effective extraction was achieved by using a combination of liquid CO2/acetone/water (10/72/18, v/v/v) at 60 °C, 350 bar, 30 min and 2 mL min-1 flow rate. The optimized method provided detection of 13 LMs and 6 lignin dimers (LDs) from the hardwood chips. The results demonstrate the potential of supercritical fluids and green solvents in the field of mild and bening lignin extraction from wood.

Focusing on Volatile Organic Compounds of Natural Resins by Selected-Ion Flow Tube-Mass Spectrometry.

The analysis of archeological artifacts, due to the high value of antique objects, is preferably performed by nondestructive, noninvasive, and in situ techniques. At present, the most common in situ protocols used for the analysis of organic materials are spectroscopic approaches. In this work, we tested selected-ion flow tube-mass spectrometry (SIFT-MS), a transportable mass spectrometry system for the characterization and discrimination of natural resins by the analysis of their volatile organic compounds profiles. We chose diterpenoid, triterpenoid, and aromatic resins as reference materials, focusing on the most identified in archeological artifacts. This work aims to create a SIFT-MS database of mass spectra suitable for characterizing archeological samples. The spectral data obtained by SIFT-MS were interpreted with the aid of chromatograms and mass spectra obtained by head space-gas chromatography/mass spectrometry (HS-GC/MS). Finally, principal components analysis (PCA) was used to further underline the differences among the different materials and to investigate the possibility of discriminating different classes of resins based on their SIFT spectra.

Co-pyrolysis of biomass and plastic: Synergistic effects and estimation of elemental composition of pyrolysis oil by analytical pyrolysis-gas chromatography/mass spectrometry.

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.

A genome sequence from a modern human skull over 45,000 years old from Zlatý kun in Czechia.

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 kun, 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 kun is one of the earliest Eurasian inhabitants following the expansion out of Africa.

Molecular profiling of Peru Balsam reveals active ingredients responsible for its pharmaceutical properties.

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.

Profiling of high molecular weight esters by flow injection analysis-high resolution mass spectrometry for the characterization of raw and archaeological beeswax and resinous substances.

This work presents a method to characterize high molecular esters in beeswax and resinous substances based on the use of microwave-assisted extraction and flow injection analysis-high resolution mass spectrometry that combines the high efficiency of the extraction procedure with the advantages of high resolution mass spectrometry. This approach allows us to identify archaeological beeswax and plant resinous substances by the characterization of the survived intact high molecular weight components. By this way, several raw materials (beeswax, pine resin and pitch, and resin extracted from Euphorbia tirucalli) were studied and used as reference substances. The procedure was then tested on an adhesive dated 44-42 ka BP recovered from Border Cave (KwaZulu-Natal, Africa), allowing us to detect the high molecular weight species even after almost 50,000 years, and then used to chemically investigate unknown archaeological adhesives from Antinoopolis (Egypt), dated to the 4th-5th century AD. The results allowed us to extend our knowledge on the long-term behavior of beeswax and resinous substances.

SIFT-ing archaeological artifacts: Selected ion flow tube-mass spectrometry as a new tool in archaeometry.

A fast non-destructive approach based on the use of portable selected ion flow tube-mass spectrometry (SIFT-MS) was used for the first time to characterize organic materials in archaeological artifacts. The high sensitivity, specificity and selectivity SIFT soft chemical ionization mass spectrometry enabled us to investigate the composition of organic residues collected from ancient Egyptian findings in order to demonstrate the robustness of the techniques with different matrices. In addition, we tested SIFT-MS directly on an archaeological Egyptian amphora to prove its suitability as a completely non-invasive technique. Parallel investigations on all the samples were performed by GC/MS analysis to correlate and confirm the data obtained by SIFT-MS. The possibility of using a portable mass spectrometer on an excavation site or in a museum would be a significant step forward in the non-invasive analysis of organic archaeological materials, enabling archeologists and conservators to obtain real-time information on the molecular composition of organic residues.

Assessing the efficiency of supercritical fluid extraction for the decontamination of archaeological bones prior to radiocarbon dating.

Bone is one of the main sample types used for building chronologies in archaeology. It is also used in other research areas such as palaeodiet and palaeoenvironmental studies. However, for results to be accurate, samples must be free of exogenous carbon. Contamination can originate from a wide range of sources in the post-depositional environment but may also occur during excavation and post excavation activities (i.e. with the application of conservation materials) or during laboratory handling. Efficient procedures to remove contamination are therefore crucial prior to radiocarbon or stable isotope measurements. This work describes the development of an innovative sample pretreatment for bones, based on using supercritical CO2, which shows unique solvation properties. The effectiveness of supercritical fluid extraction (SFE) to remove conservation materials was compared with that obtained when applying a routine extraction based on the use of organic solvents (methanol, acetone and chloroform). The chemical composition of the bone samples before and after the two pre-treatments was then investigated using analytical pyrolysis-based techniques: EGA-MS (Evolved Gas Analysis-Mass Spectrometry) and Py-GC/MS (Pyrolysis-Gas Chromatography coupled with Mass Spectrometry). Collagen samples extracted from the same bones, prepared with the two cleaning protocols, were also radiocarbon dated by Accelerator Mass Spectrometry (AMS). The results of this study show that SFE is an efficient alternative method because it was as effective as the established treatment protocol. It removes contaminants such as conservation materials from bone samples with a minimum of handling and can be used routinely in radiocarbon dating laboratories. This work also demonstrates that analytical pyrolysis is not only a very efficient method to identify contaminants in bones but also to assess the effectiveness of the pretreatment prior to the radiocarbon measurement of the samples.

Compound-specific radiocarbon dating and mitochondrial DNA analysis of the Pleistocene hominin from Salkhit Mongolia.

A skullcap found in the Salkhit Valley in northeast Mongolia is, to our knowledge, the only Pleistocene hominin fossil found in the country. It was initially described as an individual with possible archaic affinities, but its ancestry has been debated since the discovery. Here, we determine the age of the Salkhit skull by compound-specific radiocarbon dating of hydroxyproline to 34,950-33,900 Cal. BP (at 95% probability), placing the Salkhit individual in the Early Upper Paleolithic period. We reconstruct the complete mitochondrial genome (mtDNA) of the specimen. It falls within a group of modern human mtDNAs (haplogroup N) that is widespread in Eurasia today. The results now place the specimen into its proper chronometric and biological context and allow us to begin integrating it with other evidence for the human occupation of this region during the Paleolithic, as well as wider Pleistocene sequences across Eurasia.

Olive mill wastewaters: quantitation of the phenolic content and profiling of elenolic acid derivatives using HPLC-DAD and HPLC/MS2 with an embedded polar group stationary 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-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.

Effect of ball-milling on crystallinity index, degree of polymerization and thermal stability of cellulose.

A combined study of crystallinity index (CI), degree of polymerisation (DP) and thermal stability of cellulose was carried out for monitoring the effect of ball-milling. DP and CI are two fundamental quantities that describe the physico-chemical behaviour of cellulose. Milling is a common strategy to reduce cellulose crystallinity. In this work, four different commercially available celluloses were milled at 30, 60 and 120 min, and the changes in DP and CI were monitored using spectroscopic, diffraction and chromatographic techniques. Evolved gas analysis-mass spectrometry (EGA-MS) was also used to evaluate the changes in apparent activation energy (Ea) of the pyrolysis reaction upon different milling times by using model-free isoconversional methods. The results showed substantial decrease in CI values and moderate changes in DP after two-hours of ball-milling. Ea were found in the range 110-140 kJ/mol, and were reduced by 10% on average after two hours of ball-milling.

A comparison of fast and reactive pyrolysis with insitu derivatisation of fructose, inulin and Jerusalem artichoke (Helianthus tuberosus).

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.

Recent Advances in Analytical Pyrolysis to Investigate Organic Materials in Heritage Science.

The molecular characterization of organic materials in samples from artworks and historical objects traditionally entailed qualitative and quantitative analyses by HPLC and GC. Today innovative approaches based on analytical pyrolysis enable samples to be analysed without any chemical pre-treatment. Pyrolysis, which is often considered as a screening technique, shows previously unexplored potential thanks to recent instrumental developments. Organic materials that are macromolecular in nature, or undergo polymerization upon curing and ageing can now be better investigated. Most constituents of paint layers and archaeological organic substances contain major insoluble and chemically non-hydrolysable fractions that are inaccessible to GC or HPLC. To date, molecular scientific investigations of the organic constituents of artworks and historical objects have mostly focused on the minor constituents of the sample. This review presents recent advances in the qualitative and semi-quantitative analyses of organic materials in heritage objects based on analytical pyrolysis coupled with mass spectrometry.

Antihyperlipidemic effect of a Rhamnus alaternus leaf extract in Triton-induced hyperlipidemic rats and human HepG2 cells.

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.

Long-lasting ergot lipids as new biomarkers for assessing the presence of cereals and cereal products in archaeological vessels.

Cereals were very important in ancient diets, however evidence from archaeological sites of the vessels used for processing or storing cereals is comparatively rare. Micro-organisms, as well as chemical-physical effects can easily degrade cereals during the burial period. This can lead to a complete cereal decay and to serious difficulties in estimating the intensity of use of the cereals by ancient populations. Here, we present a novel biomarker approach entailing the detection of secondary lipid metabolites produced by ergot fungi (genus Claviceps), which are common cereal pests. The aim was to identify the original presence of Gramineae and to indirectly establish if vessels were used for cereal storage/processing. The fatty acid and TAG-estolide profiles of the remains from more than 30 archaeological vessels were investigated by gas chromatography/mass spectrometry (GC/MS) and high performance liquid chromatography/high resolution mass spectrometry (HPLC/ESI-Q-ToF). The detection of lipids derived from ergot in archaeological and historic contexts rests on its complex chemistry, providing a unique and relatively recalcitrant chemical signature for cereals. This research demonstrated that the combination of our innovative biomarker approach along with environmental and archaeological evidence can provide unprecedented insights into the incidence of cereals and related processing activities in ancient societies.

In-depth characterization of valuable char obtained from hydrothermal conversion of hazelnut shells to levulinic acid.

For the first time, the exploitation of hazelnut shells for the combined production of levulinic acid (LA) and hydrochar was investigated. The optimization of the catalytic hydrothermal treatment was performed both in autoclave and microwave reactor, approaching a maximum LA yield of ∼9-12wt%. Hydrochars recovered with high yield (∼43-47wt%) were characterized by different techniques, including elemental and proximate analysis, heating value, FT-IR, XPS, XRD, SEM-EDX, and SAA. Their "lignite-like" energetic properties make them suitable for the energy recovery within the same biorefinery plant for LA production, thus partially offsetting the cost of the entire process. Alternatively, since the synthesized hydrochars maintain high levels of oxygenated groups, they could be smartly exploited as natural sorbents for environmental applications. The proposed integrated approach makes possible to fully exploit this waste, smartly closing its biorefinery cycle in a sustainable development perspective.

Analytical Approaches Based on Gas Chromatography Mass Spectrometry (GC/MS) to Study Organic Materials in Artworks and Archaeological Objects.

Gas chromatography/mass spectrometry (GC/MS), after appropriate wet chemical sample pre-treatments or pyrolysis, is one of the most commonly adopted analytical techniques in the study of organic materials from cultural heritage objects. Organic materials in archaeological contexts, in classical art objects, or in modern and contemporary works of art may be the same or belong to the same classes, but can also vary considerably, often presenting different ageing pathways and chemical environments. This paper provides an overview of the literature published in the last 10 years on the research based on the use of GC/MS for the analysis of organic materials in artworks and archaeological objects. The latest progresses in advancing analytical approaches, characterising materials and understanding their degradation, and developing methods for monitoring their stability are discussed. Case studies from the literature are presented to examine how the choice of the working conditions and the analytical approaches is driven by the analytical and technical question to be answered, as well as the nature of the object from which the samples are collected.

Timing in Analytical Pyrolysis: Py(HMDS)-GC/MS of Glucose and Cellulose Using Online Micro Reaction Sampler.

A novel analytical approach based on pyrolysis-gas chromatography coupled with mass spectrometry of carbohydrates with in situ silylation using hexamethyldisilazane is presented in this work for the first time. A micro reaction sampler was used to simultaneously achieve the pyrolyis reaction and facilitate the derivatization of pyrolysis products, by enabling the materials to react with the derivatizing agent in a sealed capsule at high temperature and pressure for long periods of time. This drastically increased the complete silylation of the pyrolysis products and the chromatographic resolution, resulting in less complex pyrograms and increased sensitivity toward the most stable compounds. Different results were obtained for glucose and cellulose in terms of predominant pyrolytic pathways. The formation of anhydrosugars was the preferential pyrolytic reaction for glucose, while the formation of cyclopentenones and small molecules was predominant for the pyrolysis of cellulose. Steric hindrance effects of polysaccharide chains on the efficiency of the derivatizing agent were hypothesized in order to explain the different results. A good reproducibility was found, with relative standard deviations not greater than 10%. Semiquantitative calculations showed that the partial silylation of anhydrosugars was almost completely overcome after 10 min of reactive pyrolysis. This work discloses a powerful and potentially widely applicable analytical method for the investigations of organic materials under controlled pyrolytic conditions, with the advantage of increasing the effectiveness of in situ derivatization.

Monitoring/characterization of stickies contaminants coming from a papermaking plant--Toward an innovative exploitation of the screen rejects to levulinic acid.

Recycled paper needs a lot of mechanical/chemical treatments for its re-use in the papermaking process. Some of these ones produce considerable rejected waste fractions, such as "screen rejects", which include both cellulose fibers and non-fibrous organic contaminants, or "stickies", these last representing a shortcoming both for the papermaking process and for the quality of the final product. Instead, the accepted fractions coming from these unit operations become progressively poorer in contaminants and richer in cellulose. Here, input and output streams coming from mechanical screening systems of a papermaking plant using recycled paper for cardboard production were sampled and analyzed directly and after solvent extraction, thus confirming the abundant presence of styrene-butadiene rubber (SBR) and ethylene vinyl acetate (EVA) copolymers in the output rejected stream and cellulose in the output accepted one. Despite some significant drawbacks, the "screen reject" fraction could be traditionally used as fuel for energy recovery within the paper mill, in agreement with the integrated recycled paper mill approach. The waste, which still contains a cellulose fraction, can be also exploited by means of the hydrothermal route to give levulinic acid, a platform chemical of very high value added.