Gas Chromatography Research Articles

Moldable Plastics (Polycaprolactone) can be Acutely Toxic to Developing Zebrafish and Activate Nuclear Receptors in Mammalian Cells.

Popularized on social media, hand-moldable plastics are formed by consumers into tools, trinkets, and dental prosthetics. Despite the anticipated dermal and oral contact, manufacturers share little information with consumers about these materials, which are typically sold as microplastic-sized resin pellets. Inherent to their function, moldable plastics pose a risk of dermal and oral exposure to unknown leachable substances. We analyzed 12 moldable plastics advertised for modeling and dental applications and determined them to be polycaprolactone (PCL) or thermoplastic polyurethane (TPU). The bioactivities of the most popular brands advertised for modeling applications of each type of polymer were evaluated using a zebrafish embryo bioassay. While water-borne exposure to the TPU pellets did not affect the targeted developmental end points at any concentration tested, the PCL pellets were acutely toxic above 1 pellet/mL. The aqueous leachates of the PCL pellets demonstrated similar toxicity. Methanolic extracts from the PCL pellets were assayed for their bioactivity using the Attagene FACTORIAL platform. Of the 69 measured end points, the extracts activated nuclear receptors and transcription factors for xenobiotic metabolism (pregnane X receptor, PXR), lipid metabolism (peroxisome proliferator-activated receptor γ, PPARγ), and oxidative stress (nuclear factor erythroid 2-related factor 2, NRF2). By nontargeted high-resolution comprehensive two-dimensional gas chromatography (GC × GC-HRT), we tentatively identified several compounds in the methanolic extracts, including PCL oligomers, a phenolic antioxidant, and residues of suspected antihydrolysis and cross-linking additives. In a follow-up zebrafish embryo bioassay, because of its stated high purity, biomedical grade PCL was tested to mitigate any confounding effects due to chemical additives in the PCL pellets; it elicited comparable acute toxicity. From these orthogonal and complementary experiments, we suggest that the toxicity was due to oligomers and nanoplastics released from the PCL rather than chemical additives. These results challenge the perceived and assumed inertness of plastics and highlight their multiple sources of toxicity.

Validation of a Headspace Gas Chromatography with Flame Ionization Detection Method to Quantify Blood Alcohol Concentration (BAC) for Forensic Practice

Alcohol consumption is a major social and forensic issue. It is often the cause of road accidents, industrial accidents, suicides and other crimes. On account of this, it is of fundamental importance in forensic toxicology to correctly quantify blood alcohol concentration (BAC). In this work, a straightforward method for the quantification of ethanol from blood samples by means of headspace gas chromatography with flame ionization detection is presented and validated. For method validation linearity, limit of detection (LOD), lower limit of quantification (LLOQ), accuracy, precision (% CV) and interference studies were carried out. All the validation conditions were satisfied according to the acceptance criteria. Proof of applicability was performed on 50 real blood samples, showing that the method was effective.

Insecticidal Potential of Essential Oils from Ammi visnaga L. and Trachyspermum ammi L. against Sitophilus oryzae (L.) and In Silico Study of Their Major Constituents

There is a high interest in utilizing natural bioactive products derived from plants as a substitute for synthetic chemicals in the industry. This research focuses on the phytochemical composition of essential oils (EOs) of Ammi visnaga L. and Trachyspermum ammi L and their insecticidal activity against Sitophilus oryzae (L.), a common pest found in stored cereals. The EOs were extracted through steam distillation and analyzed using gas chromatography coupled with mass spectrometry (GC-MS). The EOs of A. visnaga consisted of twenty-four components, with Abietadiene (41.23%) being the most abundant, followed by linalool (25.54%) and limonene (19.04%). On the other hand, the EOs of T. ammi consisted of twenty-eight main components, with isothymol being the most abundant (51.88%). The results revealed that the EOs of T. Ammi (DL50 = 0.1 µL EOs/L of air) were more toxic than A. visnaga (0.38 µL EOs/L of air), with the toxicity varying based on doses and exposure periods. To further understand the molecular mechanisms underlying this activity, molecular docking and dynamic simulations were performed using the major chemical constituents of the oils. The simulation results indicated that the major compounds, Abietadiene and isothymol, interact with the catalytic sites of the target proteins, inhibiting acetylcholinesterase and chitin synthase. These interactions form energetically favorable systems that remain stable throughout the molecular dynamic period. This research provides valuable insights into the potential of these EOs as natural insecticides and highlights the importance of molecular modeling in understanding the biological activities of plant-derived compounds.

Metabolic Profiling Changes Induced by Fermented Blackberries in High-Fat-Diet-Fed Mice utilizing Gas Chromatography–Mass Spectrometry Analysis

The aim of this study was to investigate the metabolic changes associated with the anti-obesity effects of fermented blackberry extracts in the liver tissues of high-fat-diet-fed mice using mass spectrometry-based metabolomics analysis. C57BL/6J mice were divided into eight groups: normal-diet-fed mice, high-fat-diet-fed mice, high-fat diet treated with blackberry extract, high-fat-diet mice treated with blackberry fermented by L. plantarum, and high-fat diet with blackberry fermented by L. brevis. After 12 weeks, the high-fat-diet group exhibited a greater increase in liver weight compared to the control group, and among the groups, the group administered with blackberry fermented with L. plantarum showed the most pronounced reduction in liver weight. As the primary organ responsible for amino acid metabolism, the liver is crucial for maintaining amino acid homeostasis. In our study, we observed that the levels of several essential amino acids, including isoleucine and valine, were decreased by the high-fat diet, and were recovered by administration of blackberry extract fermented with L. plantarum. Our results demonstrated the potential of blackberry extract fermented with L. plantarum as a functional material for metabolic disorders by restoring some of the amino acid metabolism disturbances induced by a high-fat diet.

Unveiling Hidden Insights in Gas Chromatography Data Analysis with Generative Adversarial Networks

The gas chromatography analysis method for chemical substances enables accurate analysis to precisely distinguish the components of a mixture. This paper presents a technique for augmenting time-series data of chemicals measured by gas chromatography instruments with artificial intelligence techniques such as generative adversarial networks (GAN). We propose a novel GAN algorithm called GCGAN for gas chromatography data, a unified model of autoencoder (AE) and GAN for effective time-series data learning with an attention mechanism. The proposed GCGAN utilizes AE to learn a limited number of data more effectively. We also build a layer of high-performance generative adversarial neural networks based on the analysis of the features of data measured by gas chromatography instruments. Then, based on the proposed learning, we synthesize the features embedded in the gas chromatography data into a feature distribution that extracts the temporal variability. GCGAN synthesizes the features embedded in the gas chromatography data into a feature distribution that extracts the temporal variability of the data over time. We have fully implemented the proposed GCGAN and experimentally verified that the data augmented by the GCGAN have the characteristic properties of the original gas chromatography data. The augmented data demonstrate high quality with the Pearson correlation coefficient, Spearman correlation coefficient, and cosine similarity all exceeding 0.9, significantly enhancing the performance of AI classification models by 40%. This research can be effectively applied to various small dataset domains other than gas chromatography data, where data samples are limited and difficult to obtain.

Evaluating the Susceptibility of Different Crops to Smoke Taint

The potential for grapes and wine to be tainted following vineyard exposure to wildfire smoke is well established, with recent studies suggesting hops and apples (and thus beer and cider) can be similarly affected. However, the susceptibility of other crops to ‘smoke taint’ has not yet been investigated. Smoke was applied to a selection of fruits and vegetables, as well as potted lavender plants, and their volatile phenol composition determined by gas chromatography–mass spectrometry to evaluate their susceptibility to contamination by smoke. Volatile phenols were observed in control (unsmoked) capsicum, cherry, lavender, lemon, spinach and tomato samples, typically at ≤18 µg/kg, but 52 µg/kg of guaiacol and 83–416 µg/kg of o- and m-cresol and 4-methylsyringol were detected in tomato and lavender samples, respectively. However, significant increases in volatile phenol concentrations were observed as a consequence of smoke exposure; with the highest volatile phenol levels occurring in smoke-exposed strawberry and lavender samples. Variation in the uptake of volatile phenols by different crops was attributed to differences in their physical properties, i.e., their surface area, texture and/or cuticle composition, while the peel of banana, lemon, and to a lesser extent apple samples, mitigated the permeation of smoke-derived volatile phenols into pulp. Results provide valuable insight into the susceptibility of different crops to smoke contamination.

Efficient Stereoselective Biotransformation of Prochiral Carbonyls by Endophytic Fungi from Handroanthus impetiginosus

Endophytic microorganisms are promising sources for new biocatalysts as they must deal with their host plants’ chemicals by developing adaptative strategies, such as enzymatic pathways. As part of our efforts in selecting endophytic strains as biocatalysts, this study describes the screening of endophytic fungi isolated from Handroanthus impetiginosus leaves for selective bioreduction of Acetophenone. The bioreductions were monitored by chiral gas chromatography and conducted to the selection of the endophyte Talaromyces sp. H4 as capable of reducing acetophenone to (S)-1-phenylethanol in excellent conversion and enantiomeric excess rates. The influence of seven parameters on the stereoselective bioreduction of acetophenone by Talaromyces sp. H4 was studied: reaction time, inoculum charge, shaking, pH, temperature, substrate concentration, and co-solvent. The optimal conditions were then used to reduce substituted acetophenones and Acetophenone scale-up, which furnished (S)-1-Phenylethanol in 73% yield and 96% ee. The results highlight the endophytic fungus Talaromyces sp. H4 as an excellent biocatalyst for stereoselective reduction of prochiral carbonyls.

Human exposure to endocrine-disrupting organochlorine and organophosphate pesticides in locally produced and imported honey in Nigeria

ABSTRACT The practice of exposing honeybees to pesticides by bee-keepers or via agricultural crops, is one of the ways in which honey becomes contaminated with pesticides. Though honey has many health advantages, however, human exposure to pesticides via consumption of honey has generated public health concerns due to their endocrine-disruptive abilities. Thus, this study evaluated human exposure to endocrine-disrupting pesticides in honey from Nigeria to establish the safety of honey consumed in Nigeria. Honey were analyzed for pesticides using a gas chromatograph combined with an electron capture detector. The concentrations of ∑20 OCPs and ∑14 OPPs in the honey ranged from 0.45-1045 ng/g and 1.13-632 ng/g respectively. The values of both individual and cumulative non-carcinogenic and carcinogenic risks for humans were <1 and 1 × 10−4 respectively suggesting that there are no potential health risks via the honey consumption. The source analysis showed that pesticides in these honey originated from historical and recent/fresh use.

Antioxidant Activities of Ethanolic Extracts Obtained from α-Pinene-Containing Plants and Their Use in Cosmetic Emulsions

α-Pinene is the bicyclic, unsaturated terpene hydrocarbon present in many plants. Due to its beneficial chemical properties, this compound is of great interest and has found numerous applications as a raw material in many chemical industries as well as in medicine and cosmetics. The aim of this study was to evaluate the antioxidant activities of ethanolic extracts obtained from plants containing α-pinene and to test the properties of cosmetic emulsions prepared with these extracts. The raw plant materials consisted of fresh parts of Pinus sylvestris L., such as cones, needles, and branches, as well as dried unground and ground pinecones; dried and fresh Rosmarinus officinalis leaves; dried Levisticum officinale leaves; and dried Salvia officinalis L. leaves. The plant materials were individually extracted with 40% (v/v), 70% (v/v), and 96% (v/v) ethanol using ultrasound-assisted extraction (UAE) for 15, 30, or 60 min. This method is a green extraction technique, frequently applied to isolate active substances from plants. For the selected plant materials, Soxhlet extraction with 96% (v/v) ethanol was also performed. The qualitative and quantitative analyses of the components in the selected extracts were performed with gas chromatography coupled with mass spectrometry (GC-MS). The antioxidant activities of the extracts were evaluated with the DPPH and ABTS methods. The extracts of three plant materials with the highest antioxidant activities—dried Rosmarinus officinalis leaves, dried Salvia officinalis L. leaves, and dried and ground Pinus sylvestris L. cones—were selected to be incorporated in cosmetic emulsions containing glyceryl monostearate and Olivem 1000 as emulsifiers. The stabilities and antioxidant activities of the emulsions were evaluated. Moreover, the antimicrobial properties of the emulsions using microbiological tests were also determined. The findings suggest that the prepared emulsions are stable cosmetic products with a high antioxidant potential.

Comprehensive multiomics analysis of the signatures of gastric mucosal bacteria and plasma metabolites across different stomach microhabitats in the development of gastric cancer.

As an important component of the microenvironment, the gastric microbiota and its metabolites are associated with tumour occurrence, progression, and metastasis. However, the relationship between the gastric microbiota and the development of gastric cancer is unclear. The present study investigated the role of the gastric mucosa microbiome and metabolites as aetiological factors in gastric carcinogenesis. Gastric biopsies from different stomach microhabitats (n = 70) were subjected to 16S rRNA gene sequencing, and blood samples (n = 95) were subjected to untargeted metabolome (gas chromatography‒mass spectrometry, GC‒MS) analyses. The datasets were analysed using various bioinformatics approaches. The microbiota diversity and community composition markedly changed during gastric carcinogenesis. High Helicobacter. pylori colonization modified the overall diversity and composition of the microbiota associated with gastritis and cancer in the stomach. Most importantly, analysis of the functional features of the microbiota revealed that nitrate reductase genes were significantly enriched in the tumoral microbiota, while urease-producing genes were significantly enriched in the microbiota of H. pylori-positive patients. A panel of 81 metabolites was constructed to discriminate gastric cancer patients from gastritis patients, and a panel of 15 metabolites was constructed to discriminate H. pylori-positive patients from H. pylori-negative patients. receiver operator characteristic (ROC) curve analysis identified a series of gastric microbes and plasma metabolites as potential biomarkers of gastric cancer. The present study identified a series of signatures that may play important roles in gastric carcinogenesis and have the potential to be used as biomarkers for diagnosis and for the surveillance of gastric cancer patients with minimal invasiveness.

An investigation of some persistent organic pollutants in loggerhead sea turtles (Caretta caretta)

The study assessed persistent organic pollutants (POPs) in Caretta caretta turtles along Turkish coasts, analyzing bioaccumulation in accessible organs and discerning sex-related differences. Ten adult turtles (5 males, 5 females) from Mugla province were sampled post-mortem. Various tissues were analyzed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and polycyclic aromatic hydrocarbons (PAHs) using gas chromatography–mass spectrometry. DDT distribution showed no sex-based difference, with concentrations highest in fat tissue followed by liver, kidney, muscle, spleen, and heart. Male PCB concentrations ranked highest in fat, followed by kidney, liver, spleen, muscle, and heart, while females showed a similar trend. PAH concentrations were highest in fat for both sexes, followed by various organs. Limited PBDE concentrations hindered comprehensive evaluation. Overall, C. caretta act as effective bioindicators for monitoring environmental pollution, with certain POPs exhibiting sex and organ-based variations.

Endophytic Aspergillus fumigatiaffinis: Novel paclitaxel production and optimization insights

This study investigated the potential of endophytic fungi to produce paclitaxel (Taxol®), a potent anticancer compound widely employed in chemotherapy. This research aimed to identify, confirm, and characterize endophytic fungi capable of paclitaxel (PTX) production and assess their paclitaxel yield. Additionally, it aimed to investigate factors influencing paclitaxel production. A total of 100 endophytic fungal isolates were collected and identified from the roots of Artemisia judaica. Aspergillus fumigatiaffinis exhibited the highest PTX production (26.373 μg L−1) among the isolated endophytic fungi. The strain was identified as A. fumigatiaffinis (Accession No. PP235788.1). Molecular identification confirmed its novelty, representing the first report of PTX production by A. fumigatiaffinis, an endophyte of Artemisia judaica. Optimization through full factorial design of experiments (DOE) and response surface methodology (RSM) significantly enhanced PTX production to 110.23 μg L−1 from 1 g of dry weight of the fungal culture under optimal conditions of pH 8.0, 150 μg L−1 becozyme supplementation, and 18 days of fermentation in potato dextrose broth. The presence of paclitaxel was confirmed using thin layer chromatography, high performance liquid chromatography, and gas chromatography–mass spectrometry. These findings maximize the role of endophytic fungus to produce a secondary metabolite that might be able to replace the chemically produced PTX and gives an opportunity to provide a sustainable source of PTX eco-friendly at high concentrations.Key points• Endophytic fungi, like A. fumigatiaffinis, show promise for eco-friendly paclitaxel production• Optimization strategies boost paclitaxel yield significantly, reaching 110.23 μg L−1• Molecular identification confirms novelty, offering a sustainable PTX source

An in-depth study of the oxidative liquefaction process for polymeric waste reduction and chemical production from wind turbine blades and personal protective equipment used in the medical field

An in-depth study of the oxidative liquefaction process has been provided to degrade the polymeric waste from personal protective equipment (PPEs) and wind turbine blades (WTBs). Thermogravimetric investigations demonstrate that WTBs have three prominent peaks throughout the degradation, whereas PPEs display solitary peak features. Experiments are carried out employing specific experimental design approaches, namely the Central Composite Face-Centered Plan (CCF) for WTBs and the Central Composition Design with Fractional Factorial Design for PPEs in a batch-type reactor at temperature ranges of 250–350 °C, pressures of 20–40 bar, residence times of 30–90 min, H2O2 concentrations of 15–45 %, and waste/liquid ratios of 5–25 % for WTBs. These values were 200–300 °C, 30 bar, 45 min, 30–60 % and 5–7 % for PPE. A detailed comparison has been provided in the context of total polymer degradation (TPD) for PPE and WTBs. Liquid products from both types of wastes after the oxidative liquefaction process are subjected to gas chromatography with flame ionization detection (GC-FID) to identify the existence of oxygenated chemical compounds (OCCs). For WTBs, TPD was 20–49 % and this value was 55–96 % for PPE while the OCC yield for WTBs (36.31 g/kg - 210.59 g/kg) and PPEs (39.93 g/kg - 212.66 g/kg) was also calculated. Detailed optimization of experimental plans was carried out by performing the analysis of variance (ANOVA) and optimization goals were maximum TPD and OCCs yields against the minimum energy consumption, though a considerable amount of complex polymer waste can be reduced and high concentrations of OCC can be achieved, which could be applied for commercial and environmental benefits.

Bioactive compounds from the bark of &lt;i&gt;Juniperus communis&lt;/i&gt; (Cupressaceae)

The paper presents the results of the study of Juniperus communis L. (Cupressaceae) bark composition. It is shown that the juniper’s bark contains 3.5 times more extractives than its wood. Individual component composition of ethanol and petroleum extracts of J. communis bark was confirmed using gas chromatography – mass spectrometry. Difference in the component composition of ethanol and petroleum bark extracts was determined. The major constituents of J. communis ethanol extract are monosaccharides, disaccharides and resin acids; of petroleum extract – resin and fatty acids, and sterols. It has been established, that ethanol extract of J. communis bark exhibit high antioxidant activity. The ABTS radical inhibition activity of the bark alcoholic extract reached 86–87%. Based on the conducted research, it can be concluded that in the subarctic region the bark of J. communis is a source of valuable bioactive substances.

Aromatic Profiling of New Table Grape Varieties Using Gas Chromatography/Mass Spectrometry and Olfactometry

The aim of this study is the aromatic characterization of new table grape varieties, namely Guzun (V. vinifera), Melona (V. vinifera), Cotton Candy (V. vinifera), IVC SA3 (V. labrusca), and IVC SB1 (V. labrusca). The qualitative and quantitative analysis of odorant molecules present in the berries allows for the definition of the aroma profile of the grape. This analysis benefits from the progress of analytical techniques and sensory methodologies. Gas chromatography/mass detection enable the efficient detection of the substances present and their concentrations. Through the coupling of gas chromatography with sensory detection (gas chromatography-olfactometry), it is possible to correlate the compounds detected by gas chromatography with olfactory stimuli, exploiting the human olfactory system. Aroma, a significant flavor component, is an important attribute of table grape that contributes to defining their quality. This characteristic is highly valued by consumers, and consequently, the market asks for table grapes with a particular or new aroma. Aromatic characterization is a crucial step in the study of the table grape varieties to evaluate their potential at the commercial level or, for instance, in breeding programs focusing on organoleptic properties.

Short term effect of antimicrobial photodynamic therapy and probiotic L. salivarius WB21 on halitosis: A controlled and randomized clinical trial.

This study aimed to evaluate the effect of antimicrobial photodynamic therapy (aPDT) and the use of probiotics on the treatment of halitosis. Fifty-two participants, aged from 18 to 25 years, exhaling sulfhydride (H2S) ≥ 112 ppb were selected. They were allocated into 4 groups (n = 13): Group 1: tongue scraper; Group 2: treated once with aPDT; Group 3: probiotic capsule containing Lactobacillus salivarius WB21 (6.7 x 108 CFU) and xylitol (280mg), 3 times a day after meals, for 14 days; Group 4: treated once with aPDT and with the probiotic capsule for 14 days. Halimetry with gas chromatography (clinical evaluation) and microbiological samples were collected from the dorsum of the tongue before and after aPDT, as well as after 7, 14, and 30 days. The clinical data failed to follow a normal distribution; therefore, comparisons were made using the Kruskal-Wallis test (independent measures) and Friedman ANOVA (dependent measures) followed by appropriate posthoc tests, when necessary. For the microbiological data, seeing as the data failed to follow a normal distribution, the Kruskal-Wallis rank sum test was performed with Dunn's post-test. The significance level was α = 0.05. Clinical results (halimetry) showed an immediate significant reduction in halitosis with aPDT (p = 0.0008) and/or tongue scraper (p = 0.0006). Probiotics showed no difference in relation to the initial levels (p = 0.7530). No significant differences were found in the control appointments. The amount of Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola were not altered throughout the analysis (p = 0.1616, p = 0.2829 and p = 0.2882, respectively). There was an immediate clinical reduction of halitosis with aPDT and tongue scraping, but there was no reduction in the number of bacteria throughout the study, or differences in the control times, both in the clinical and microbiological results. New clinical trials are necessary to better assess the tested therapies. Clinical Trials NCT03996044.

Stability of selected exhaled breath volatiles stored in Tenax® TA adsorbent tubes at -80°C.

Preservation of the breath sample integrity during storage and transport is one of biggest challenges in off-line exhaled breath gas analysis. In this context, adsorbent tubes are frequently used as storage containers for use with analytical methods employing gas chromatography with mass spectrometric detection. The key objective of this short communication is to provide data on the recovery of selected breath volatiles from Tenax® TA adsorbent tubes that were stored at -80 C for up to 90 days. For this purpose, an Owlstone Medical's ReCIVA® Breath Sampler was used for exhaled breath collection. The following fifteen compounds, selected to cover a range of chemical properties, were monitored for their stability: isoprene, n-heptane, n-nonane, toluene, p-cymene, allyl methyl sulfide, 1-(methylthio)-propane, 1-(methylthio)-1-propene, -pinene, DL-limonene, β-pinene, -terpinene, 2-pentanone, acetoin and 2,3 butanedione. All compounds but one (acetoin) were found to be stable during the first 4 weeks of storage (recovery within  2×RSD). Furthermore, n-nonane was stable during the whole of the investigated period.

Prediction of the Fatty Acid Profiles of Iberian Pig Products by Near Infrared Spectroscopy: A Comparison Between Multiple Regression Tools and Artificial Neural Networks

AbstractIn this study, the feasibility of predicting the lipid profiles of Iberian ham and shoulder samples by using near infrared (NIR) spectroscopy was evaluated. Gas chromatography analysis was the reference method used. The muscles analyzed and recorded by NIR spectroscopy were 76 Biceps femoris for Iberian hams and 72 Brachiocephalicus for Iberian shoulders. NIR calibrations were carried out by using two methods: modified partial least squares regression (MPLS) and artificial neural networks (ANN). With the MPLS method, it was possible to obtain equations with regression’s coefficients (RSQ) of &gt; 0.5 for 5 individual fatty acids and 3 summations: polyunsaturated fatty acids, n3 and n6. The use of neural networks made it possible to find equations with RSQ of &gt; 0.5 for 10 individual fatty acids, all of which are present in over 90% of the samples, and 5 summations of saturated, monounsaturated, and polyunsaturated fatty acids (SFA, MUFA, PUFA), n3 and n6, finding that the calibration curves of the fatty acids C18:1, C18:2n6, and C18:3n3 presented RSQ’s of &gt; 0.7. The results obtained indicate that NIR spectroscopy could be a very useful technology for the quality control of cured products as it allows estimating the main fatty constituents quickly and without using reagents.

Characterisation of New Zealand Propolis from Different Regions Based on Its Volatile Organic Compounds

Propolis is a bee product mainly consisting of plant resins and is used by bees to maintain the structural integrity of the colony. Propolis is known to contribute to bee health via its antimicrobial activity and is a valued product for human use owing to its nutritional and medicinal properties. Propolis is often characterised into seven categories depending on the resin source. New Zealand propolis is typically assumed as being poplar-type propolis, but few studies have chemically characterised New Zealand propolis to confirm or reject this assumption. Here, for the first time, we characterise propolis originating from different regions in New Zealand based on its volatile organic compounds, using gas chromatography coupled with mass spectrometry (GC-MS). To support this characterisation, we also collected and analysed resin samples from a variety of resin-producing plants (both native to New Zealand and introduced). Our findings suggest that bees mainly use poplar as a resin source, but also utilize native plant species to produce propolis. While regional variation did not allow for clear separation between samples, some patterns emerged, with samples from some regions having more chemical complexity and a higher contribution from native species (as suggested by a higher number of compounds unique to native species resin). Further studies are needed to accurately identify the botanical sources contributing to these samples. It may be also of interest to explore the biological activity of regional propolis samples and their potential nutritional or medicinal benefits.

Unraveling the mummy's shroud: A multi-analytical study of a rare painted textile from Roman Egypt

This article describes a multi-analytical technical study of a rare painted shroud still wrapped around a female Egyptian mummy (MCABo EG 1974) in the collection of the Museo Civico Archeologico of Bologna, Italy. Long stored in the museum's warehouses, these mummified human remains were recently rediscovered within the Bologna Mummy Project (BOmp), an interdisciplinary endeavor promoted by the Museo Civico Archeologico and the Institute for Mummy Studies of Eurac Research, Bolzano, Italy. Dating to the Roman period (1st-2nd century C.E.), as confirmed by radiocarbon dating, this mummy displays a unique series of technical features, including the exceptional finding of a colorful painted shroud still preserved in its original location around the wrapped body, to which it is secured with textile straps and resin. In this context, scientific analysis aimed to deepen our current knowledge of the artistic practices of Roman Egypt through an in-depth study of the painting technique, context of production, and possible provenance of the mummy, while promoting a science-informed, enhanced approach to the preservation of the mummified human remains. This research relied on an integrated analytical protocol based on the combined use of imaging and mapping techniques, non-invasive point analysis, and micro-invasive investigation of minute samples, each carried out at the different partnering institutions. Computed tomography (CT) highlighted varying radio-densities for some of the flesh tones and red decorations. Visible photography and multiband imaging provided information on the nature and distribution of various materials on the surface. Fiber optics reflectance spectroscopy (FORS), X-ray fluorescence (XRF) spectroscopy, and Raman spectroscopy contributed to the characterization of the shroud's color palette along with optical microscopy (OM), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDS), as well as high-performance liquid chromatography coupled with diode-array detection and mass spectrometry (HPLC/DAD and HPLC/MS). Materials detected include a limited number of mineral pigments and plant-derived dyes such as red lead, red ocher, madder, an unknown yellow dye, Egyptian blue and green, and a carbon-based black. Through access to MOLAB equipment and expertise, macro-XRF (MA-XRF), as well as combined X-ray diffraction (XRD) spot analysis and mapping, enhanced pigment identification. A combination of transmission Fourier-transform infrared (FTIR) spectroscopy with gas chromatography / mass spectrometry (GC/MS) was used to identify the paint binders and any additional organic substances possibly involved in embalming practices and ritual traditions, including animal fat, plant lipid, Pinaceae resin, gum, and beeswax. Mineralogical data gathered by XRD on surface deposits and soil residues collected from within the shroud's inner folds was crucial to put forward hypotheses, in support of the stylistic study of the shroud, concerning a possible provenance from Upper Egypt, most likely West Thebes. Both the shroud and inner bandages were found to be made with linen using OM. After undergoing scientific analysis and conservation treatment, the mummy was displayed in the “Mummies. Unwrapping the past” exhibition and was featured at the 10th World Congress on Mummy Studies, both held in Bolzano in the fall of 2022.