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MonoTrapTM was introduced in 2009 as a novel miniaturized configuration for sorptive sampling. The method for the characterization of volatile organic compound (VOC) emission profiles from hot mix asphalt (HMA) consisted of a two-step procedure: the analytes, initially adsorbed into the coating in no vacuum- or vacuum-assistance mode, were then analyzed following an automated thermal desorption (TD) step. We took advantage of the theoretical formulation to reach some conclusions on the relationship between the physical characteristics of the monolithic material and uptake rates. A total of 35 odor-active volatile compounds, determined by gas chromatography-mass spectrometry/olfactometry analysis, contributed as key odor compounds for HMA, consisting mainly of aldehydes, alcohols, and ketones. Chemometric analysis revealed that MonoTrapTM RGC18-TD was the better coating in terms of peak area and equilibrium time. A comparison of performance showed that Vac/no-Vac ratios increased, about an order of magnitude, as the boiling point of target analytes increased. The innovative hybrid adsorbent of silica and graphite carbon monolith technology, having a large surface area bonded with octadecylsilane, showed effective adsorption capability, especially to polar compounds. [ABSTRACT FROM AUTHOR]

Polycystic ovary syndrome (PCOS) is a complex disorder that impacts both the endocrine and metabolic systems, often resulting in infertility, obesity, insulin resistance, and cardiovascular complications. The aim of this study is to investigate the role of intestinal flora and its metabolites, particularly short-chain fatty acids (SCFAs), in the development of PCOS, and to assess the effects of metformin therapy on these components. SCFA levels in fecal and blood samples from women with PCOS ( n = 69 ) and healthy controls ( n = 18 ) were analyzed using Gas Chromatography–Mass Spectrometry (GC/MS) for precise measurement. Fecal microbiota were quantitatively detected by real-time polymerase chain reaction (PCR). To assess the efficacy of six months of metformin treatment, changes in the microbiota and SCFAs in the PCOS group ( n = 69 ) were also evaluated. The results revealed that women with PCOS exhibited a significant reduction in beneficial bacteria (namely, the C. leptum group and Prevotella spp.) alongside a notable overgrowth of opportunistic microorganisms (C. perfringens, C. difficile, Staphylococcus spp., and Streptococcus spp.). An overproduction of acetic acid (AA, FC = 0.47 , p < 0.05 ) and valeric acid (VA, FC = 0.54 , p < 0.05 ) suggests a link between elevated SCFAs and the development of obesity and PCOS. Interestingly, AA in the bloodstream might offer a protective effect against PCOS by ameliorating key symptoms such as high body mass index ( r = − 0.33 , p = 0.02 ), insulin resistance ( r = − 0.39 , p = 0.02 ), and chronic inflammation. Although serum SCFA levels showed non-significant changes following metformin treatment ( p > 0.05 ), the normalization of AA in the gut underscores that metformin exerts a more pronounced effect locally within the gastrointestinal tract. Furthermore, the study identified the most effective model for predicting the success of metformin therapy, based on serum concentrations of butyric acid (BA) and VA, achieving a 91% accuracy rate, 100% sensitivity, and 80% specificity. These promising findings highlight the potential for developing targeted interventions and personalized treatments, ultimately improving clinical outcomes for women with PCOS. [ABSTRACT FROM AUTHOR]

Carvone, a natural monoterpene, has been identified in various plants, giving them a characteristic scent. Enantiomers (R-(–) and S-(+)) reveal specific biological activities that are successfully used in traditional medicine for their antifungal, antibacterial, antiparasitic, and anti-influenza properties. The presented paper is based on S-(+)-carvone, characterized by a specific caraway scent, which revealed rich biological activities both in vitro and in vivo. Thus, the aim of the study was to evaluate the potential anti-neurodegenerative activity of S-(+)-carvone, including in vitro experiments (butyrylcholinesterase inhibitory, neuro- and hepatotoxicity as well as neuro- and hepatoprotective activity), in vivo (memory acquisition, locomotor activity), and ex vivo (determination of S-(+)-carvone's level in tissues collected from mice). Results revealed the multidirectional character of S-(+)-carvone. It has been shown that S-(+)-carvone is capable of butyrylcholinesterase inhibition (40% for 0.025 mg applied onto the plate), and neuroprotection and hepatoprotection at selective concentrations against reactive oxygen species generation and lipid peroxidation along with non-hepatotoxicity character. Additionally, multiple-dose administration of the monoterpene at a dose of 100 mg/kg had a positive influence on memory acquisition. Gas chromatography–mass spectrometry analysis of the plasma and the brain showed that S-(+)-carvone can cross the blood–brain barrier and accumulate in the hippocampus (0.217 µg/mg of tissue), a crucial part of the brain associated with cognition and mental functions. [ABSTRACT FROM AUTHOR]

Grafting is a traditional research and crop production technique used to study the long-distance movement of molecules, reduce disease susceptibility, and improve yield, quality, and nutrient content. Tomato/potato grafts are rare examples of successful interspecies grafting, even resulting in commercially available products. Nevertheless, information on the effect of tomato on the quality parameters of potato tubers is scarce. In this study, the tomato cultivar 'Mobil' was grafted with the potato cultivars 'White Lady', 'Hópehely', and 'Désirée', and the phenotype, metabolite composition, and starch and protein contents of the tubers were analysed. Anthocyanins were isolated from the tuber skins, and the expression level of the transcription factor ANTHOCYANIN1 (StAN1) was evaluated. Out of the 112 identified metabolites, the concentrations of twelve compounds were altered in the same direction in all three cultivars. Compared to the self-grafted control, the starch content of tubers was increased in each cultivar, while the protein level remained unaltered in 'White Lady' and 'Hópehely'. The oval tubers became roundish. The tomato scion increased the anthocyanin content of 'Hópehely' and 'Désirée' tuber skins, which was correlated with the upregulation of StAN1 expression. These results indicate that tomato scion has a significant impact on the quality parameters of potato tubers. [ABSTRACT FROM AUTHOR]

Phytoncides and aromatherapy scents mainly derive from plant secondary metabolites and are now well known for their health benefits. In this study, we analyzed the chemical composition of the leaf-derived essential oil of Liquidambar formosana (Altingiaceae) using GC-MS; we also investigated the VOCs released from L. formosana leaves and the leaf essential oil at different temperatures by means of headspace gas chromatography–mass spectrometry (HS-GC-MS). Regarding the VOCs of the leaves, monoterpenes predominated the VOCs at both temperatures, mainly comprising sabinene, followed by γ-terpinene, α-terpinene, and α-pinene. The intensity of the leaf VOCs at 50 °C was nearly three times higher than that at 25 °C; the emission of monoterpenes significantly increases at higher environmental temperatures. The VOC emissions of oxygenated monoterpenes from the leaf essential oil increased at higher temperatures (50 °C), especially those of terpinen-4-ol. Our results reveal that HS-GC-MS can be used to conveniently and directly analyze the VOCs emitted from L. formosana leaves and their essential oils and to evaluate the influence of temperature on the composition of the VOCs of specimens. These VOC studies will assist in the sustainable development and utilization of L. formosana trees for forest therapy, as well as the use of their leaf essential oil for aromatherapy. [ABSTRACT FROM AUTHOR]

Ferromanganese formations are widespread in the Earth's aquatic environment. Of all the mechanisms of their formation, the biogenic one is the most debatable. Here, we studied the Fe-Mn crusts of hydrothermal fields near the underwater volcano Puy de Folles (rift valley of the Mid-Atlantic Ridge). The chemical and mineralogical composition (optical and electron microscopy with EDX, X-ray powder diffraction, X-ray fluorescence analysis, Raman and FTIR spectroscopy, gas chromatography—mass spectrometry (GC-MS)) and the magnetic properties (static and resonance methods, including at cryogenic temperatures) of the samples of Fe-Mn crusts were investigated. In the IR absorption spectra, based on hydrogen bond stretching vibrations, it was concluded that there were compounds with aliphatic (alkane) groups as well as compounds with double bonds (possibly with a benzene ring). The GC-MS analysis showed the presence of alkanes, alkenes, hopanes, and steranes. Magnetically, the material is highly coercive; the blocking temperatures are 3 and 13 K. The main carriers of magnetism are ultrafine particles and X-ray amorphous matter. The analysis of experimental data allows us to conclude that the studied ferromanganese crusts, namely in their ferruginous phase, were formed as a result of induced biomineralization with the participation of iron-oxidizing and iron-reducing bacteria. [ABSTRACT FROM AUTHOR]

This study is focused on the optimization and application of an analytical methodology for the determination of 15 selected pesticides in three substrates during the vinification process. QuEChERS extraction was used followed by GC-MS to develop a simple and rapid method for the determination of these compounds. The optimized methodology was validated, providing for all selected pesticides excellent linearity, recoveries ranging between 60.9% and 95.0% and LOQs lower than 50 ng g−1 f for all substrates. The developed methodology was tested on real samples of grapes, must and wine obtained from a winery in the Epirus region. The results indicated the existence of some of the selected pesticides at comparatively low levels in contrast to the valid MRLs. [ABSTRACT FROM AUTHOR]

The growing demand for alternative sources of non-animal proteins has stimulated research in this area. Mushrooms show potential in the innovation of plant-based food products. In this study, the aim was to develop prototype fish fillets analogues from Pleurotus ostreatus mushrooms applying enzymatic treatment (β-glucanase and transglutaminase-TG). A Plackett–Burman 20 experimental design was used to optimize forty variables. Oat flour (OF) exerted a positive effect on the hardness and gumminess texture parameters but a negative effect on cohesiveness and resilience. Soy protein isolate (SPI) exhibited a positive effect on elasticity, gumminess and chewiness, while acacia gum had a negative effect on elasticity, cohesiveness and resilience. After sensory analysis the assay with 1% cassava starch, 5% OF, 5% SPI, 0.1% transglutaminase (240 min/5 °C), 1% coconut oil, 1% soybean oil, 0.2% sodium tripolyphosphate, 0.6% β-glucanase (80 °C/10 min) and without β-glucanase inactivation was found to exhibit greater similarity to fish fillet. The classes hydrocarbons, alcohols and aldehydes are the predominant ones in aromatic profile analysis by chromatography and electronic nose. It is concluded that a mushroom-based analogue of fish fillet can be prepared using enzymatic treatment with TG. [ABSTRACT FROM AUTHOR]

Angomonas deanei belongs to Trypanosomatidae family, a family of parasites that only infect insects. It hosts a bacterial endosymbiont in a mutualistic relationship, constituting an excellent model for studying organelle origin and cellular evolution. A lipidomic approach, which allows for a comprehensive analysis of all lipids in a biological system (lipidome), is a useful tool for identifying and measuring different expression patterns of lipid classes. The present study applied GC-MS and NMR techniques, coupled with principal component analysis (PCA), in order to perform a comparative lipidomic study of wild and aposymbiotic A. deanei grown in the presence or absence of FBS. Unusual contents of branched-chain iso C17:0 and C19:0-cis-9,10 and-11,12 fatty acids were identified in A. deanei cultures, and it was interesting to note that their content slightly decreased at the log phase culture, indicating that in the latter growth stages the cell must promote the remodeling of lipid synthesis in order to maintain the fluidity of the membrane. The combination of analytical techniques used in this work allowed for the detection and characterization of lipids and relevant contributors in a variety of A. deanei growth conditions. [ABSTRACT FROM AUTHOR]

This research aimed to analyze the impact of two different non-Saccharomyces yeast species on the aromatic profile of red wines made from the cv. Babić (Vitis vinifera L.) red grape variety. The grapes were obtained from two positions in the Middle and South of Dalmatia. This study compared a control treatment with the Saccharomyces cerevisiae (Sc) strain as a type of sequential inoculation treatment with Lachancea thermotolerans (Lt x Sc) and Torulaspora delbrueckii (Td x Sc). The focus was on the basic wine parameters and volatile aromatic compound concentrations determined using the SPME-Arrow-GC/MS method. The results revealed significant differences in cis-linalool oxide, geraniol, neric acid, and nerol, which contribute to the sensory profile with floral and rose-like aromas; some ethyl esters, such as ethyl furoate, ethyl hexanoate, ethyl lactate, ethyl 2-hydroxy-3-methylbutanoate, ethyl 3-hydroxy butanoate, diethyl glutarate, and diethyl succinate, contribute to the aromatic profile with fruity, buttery, overripe, or aging aromas. A sensory evaluation of wines confirmed that Td x Sc treatments exhibited particularly positive aromatic properties together with a more intense fullness, harmony, aftertaste, and overall impression. [ABSTRACT FROM AUTHOR]

Bamboo vinegar is a liquid biomass with a huge yield and complex chemical composition. At present, the relative quantification of bamboo vinegar has been investigated in most studies. To analyze twelve compounds from bamboo vinegar simultaneously, gas chromatography-mass spectrometry and an external standard method were used to develop an analytical method. In this method, chromatographic separations of all compounds were above 1.5. The linear range was between 0.100 and 10.000 mg/L, and the coefficient of determination (R2) was between 0.9981 and 0.9997, indicating a good linear relationship. The limit of detection (LOD) was between 0.004 and 0.780 mg/L; the limit of quantitation (LOQ) was between 0.016 and 3.120 mg/L; the relative standard deviations (RSDs) of instrument precision and method stability were less than 8%; the recovery rate was between 89.25% and 113.77%, and its RSD was between 0.44% and 5.70%. Using this method, fourteen bamboo vinegars and six wood vinegars were analyzed, and it was found that the content of propionic acid, phenol, and 2-methoxyphenol was higher in most samples. In addition, the differences in physicochemical properties between distilled bamboo vinegar and its original solution after atmospheric distillation were investigated. [ABSTRACT FROM AUTHOR]

Cuticular waxes are essential for protecting plants from various environmental stresses. Allium fistulosum serves as an excellent model for investigating the regulatory mechanisms underlying cuticular wax synthesis with notable epidermal wax characteristics. A combination of gas chromatography–mass spectrometry (GC–MS) metabolite analysis and transcriptomics was used to investigate variations in metabolites and gene expression patterns between the wild type (WT) and glossy mutant type (gl2) of A. fistulosum. The WT surface had a large number of acicular and lamellar waxy crystals, whereas the leaf surface of gl2 was essentially devoid of waxy crystals. And the results revealed a significant decrease in the content of 16-hentriacontanone, the principal component of cuticular wax, in the gl2 mutant. Transcriptomic analysis revealed 3084 differentially expressed genes (DEGs) between WT and gl2. Moreover, we identified 12 genes related to fatty acid or wax synthesis. Among these, 10 DEGs were associated with positive regulation of wax synthesis, whereas 2 genes exhibited negative regulatory functions. Furthermore, two of these genes were identified as key regulators through weighted gene co-expression network analysis. Notably, the promoter region of AfisC5G01838 (AfCER1-LIKE1) exhibited a 258-bp insertion upstream of the coding region in gl2 and decreased the transcription of the AfCER1-LIKE1 gene. This study provided insights into the molecular mechanisms governing cuticular wax synthesis in A. fistulosum, laying the foundation for future breeding strategies. [ABSTRACT FROM AUTHOR]

Featured Application: The findings of this study shed light on the intricate relationship between the cooking techniques, volatile compound formation, and consumer acceptance of beef meat. By employing Solid-Phase Microextraction (SPME) and gas chromatography–mass spectrometry (GC-MS) methods to analyze volatile "marker" compounds, the study delineates significant disparities in flavor profiles arising from roasting versus stewing methods. The objective of this study is to determine the effect of two distinct cooking techniques, namely roasting and stewing, on the formation of volatile compounds in various beef muscles (Semimembranosus, Biceps femoris, and Rectus femoris) and how this relates to consumer acceptance. The research employs the concept of volatile "marker" compounds to discern the influence of cooking techniques on the flavor profile of beef. Eighteen "marker compounds" were selected to represent a number of the mechanisms of formation and quantified in beef subjected to two different cooking methods. While no statistically significant differences were observed in consumer evaluations between the two cooking methods, notable disparities emerged in the consumer assessments of specific muscle cuts. Notably, the Rectus femoris muscle received the highest ratings (p < 0.05) among other evaluated muscles. The utilization of Solid-Phase Microextraction (SPME) and gas chromatography–mass spectrometry (GC-MS) methods for the analysis of volatile "marker compounds" in beef proved effective in highlighting significant differences in flavor compound classes between cooking methods, and these differed between muscles. The main effect was of the cooking method with stewed beef aroma having approximately 39× more dimethyl trisulphide, 9× more dimethyl disulphide, 7× more pentanal, 3× more hexanal, and twice as much benzaldehyde and 2-methylthiophene. Dimethyldisulphide, dimethyltrisulphide, hexanal, and heptanal, therefore, emerged as characteristic volatile compounds associated with the stewing cooking technique, suggesting their potential as markers for lipid and other oxidation reactions. This work indicates that certain lipid oxidation compounds, Strecker aldehydes, and sulfur compounds can be markers for the undesirable and/or desirable flavors of cooked beef, but that this depends on the cooking method chosen. It shows that flavor differences may be understood through the analysis of volatile flavor compounds in association with palatability and other chemical measurements. [ABSTRACT FROM AUTHOR]

Pesticides are chemical substances used to kill or control various types of pests, which are hazardous for crops and animals. Pesticides may remain on or in foods after these are applied to crops. Pesticide residue in food has been a major global concern since there are direct and indirect health hazards associated with the regular consumption of foods with pesticide residues. Chlorpyrifos is one of the most used pesticides that has received much attention worldwide due to its detrimental health impact. The presence of chlorpyrifos residue in food crops can have both long-term and short-term effects on consumer health. Bangladesh is an agricultural country that uses a high volume of pesticides every year including chlorpyrifos. This experimental study aimed to analyze chlorpyrifos pesticide residue in locally grown cauliflower, cabbage, and eggplant samples by gas chromatography–mass spectrometry (GC-MS) technique followed by a suitable extraction process. Commercially available cauliflower, cabbage, and eggplant samples along with samples cultivated with the recommended pesticide dose were collected for qualitative and quantitative analysis. Samples cultivated without chlorpyrifos were collected as control samples for the validation study. The method was validated with respect to accuracy, recovery, reproducibility, linearity, limit of detection, and limit of quantification. The method has a limit of detection (LOD) of 0.011 mg/kg and a limit of quantification (LOQ) of 0.034 mg/kg. The experimental results were compared to the maximum residue level (MRL) to assess the human health impact. Chlorpyrifos residue was found in 44% of cauliflower samples with 91% of samples higher than MRL. The residue was found in 68% of cabbage samples with 53% of samples higher than MRL. For eggplant, the residue was found in 80% of the samples with 65% of samples higher than MRL. The risk assessment based on the residue level found in this study shows a potential health hazard of having a high concentration of chlorpyrifos residue in locally grown vegetables. [ABSTRACT FROM AUTHOR]

Cannabichromene (CBC) is a minor cannabinoid within the array of over 120 cannabinoids identified in the Cannabis sativa plant. While CBC does not comprise a significant portion of whole plant material, it is available to the public in a purified and highly concentrated form. As minor cannabinoids become more popular due to their potential therapeutic properties, it becomes crucial to elucidate their metabolism in humans. Therefore, the goal of this was study to identify the major CBC phase I-oxidized metabolite generated in vitro following incubation with human liver microsomes. The novel metabolite structure was identified as 2′-hydroxycannabicitran using gas chromatography–mass spectrometry and nuclear magnetic resonance spectroscopy. Following the identification, in silico molecular modeling experiments were conducted and predicted 2′-hydroxycannabicitran to fit in the orthosteric site of both the CB1 and CB2 receptors. When tested in vitro utilizing a competitive binding assay, the metabolite did not show significant binding to either the CB1 or CB2 receptors. Further work necessitates the determination of potential activity of CBC and the here-identified phase I metabolite in other non-cannabinoid receptors. [ABSTRACT FROM AUTHOR]

Pyrethroid pesticides (PYRs) have found widespread application in agriculture for the protection of fruit and vegetable crops. Nonetheless, excessive usage or improper application may allow the residues to exceed the safe limits and pose a threat to consumer safety. Thus, there is an urgent need to develop efficient technologies for the elimination or trace detection of PYRs from vegetables. Here, a simple and efficient magnetic solid-phase extraction (MSPE) strategy was developed for the simultaneous purification and enrichment of five PYRs in vegetables, employing the magnetic covalent organic framework nanomaterial COF-SiO2@Fe3O4 as an adsorbent. COF-SiO2@Fe3O4 was prepared by a straightforward solvothermal method, using Fe3O4 as a magnetic core and benzidine and 3,3,5,5-tetraaldehyde biphenyl as the two building units. COF-SiO2@Fe3O4 could effectively capture the targeted PYRs by virtue of its abundant π-electron system and hydroxyl groups. The impact of various experimental parameters on the extraction efficiency was investigated to optimize the MSPE conditions, including the adsorbent amount, extraction time, elution solvent type and elution time. Subsequently, method validation was conducted under the optimal conditions in conjunction with gas chromatography–mass spectrometry (GC-MS). Within the range of 5.00–100 μg·kg−1 (1.00–100 μg·kg−1 for bifenthrin and 2.5–100 μg·kg−1 for fenpropathrin), the five PYRs exhibited a strong linear relationship, with determination coefficients ranging from 0.9990 to 0.9997. The limits of detection (LODs) were 0.3–1.5 μg·kg−1, and the limits of quantification (LOQs) were 0.9–4.5 μg·kg−1. The recoveries were 80.2–116.7% with relative standard deviations (RSDs) below 7.0%. Finally, COF-SiO2@Fe3O4, NH2-SiO2@Fe3O4 and Fe3O4 were compared as MSPE adsorbents for PYRs. The results indicated that COF-SiO2@Fe3O4 was an efficient and rapid selective adsorbent for PYRs. This method holds promise for the determination of PYRs in real samples. [ABSTRACT FROM AUTHOR]

The intensity of the odor in food-grade paraffin waxes is a pivotal quality characteristic, with odor panel ratings currently serving as the primary criterion for its assessment. This study presents an innovative method for assessing odor intensity in food-grade paraffin waxes, employing headspace gas chromatography with mass spectrometry (HS/GC-MS) and integrating total ion spectra with advanced machine learning (ML) algorithms for enhanced detection and quantification. Optimization was conducted using Box–Behnken design and response surface methodology, ensuring precision with coefficients of variance below 9%. Analytical techniques, including hierarchical cluster analysis (HCA) and principal component analysis (PCA), efficiently categorized samples by odor intensity. The Gaussian support vector machine (SVM), random forest, partial least squares regression, and support vector regression (SVR) algorithms were evaluated for their efficacy in odor grade classification and quantification. Gaussian SVM emerged as superior in classification tasks, achieving 100% accuracy, while Gaussian SVR excelled in quantifying odor levels, with a coefficient of determination (R2) of 0.9667 and a root mean square error (RMSE) of 6.789. This approach offers a fast, reliable, robust, objective, and reproducible alternative to the current ASTM sensory panel assessments, leveraging the analytical capabilities of HS-GC/MS and the predictive power of ML for quality control in the petrochemical sector's food-grade paraffin waxes. [ABSTRACT FROM AUTHOR]

There are several highly damaging Phytophthora species pathogenic to forest trees, many of which have been spread beyond their native range by the international trade of live plants and infested materials. Such introductions can be reduced through the development of better tools capable of the early, rapid, and high-throughput detection of contaminated plants. This study utilized a volatilomics approach (solid-phase microextraction coupled to gas chromatography–mass spectrometry) to differentiate between several Phytophthora species in culture and discriminate between healthy and Phytophthora-inoculated European beech and pedunculate oak trees. We tentatively identified 14 compounds that could differentiate eight Phytophthora species from each other in vitro. All of the Phytophthora species examined, except Phytophthora cambivora, uniquely produced at least one compound not observed in the other species; however, most detected compounds were shared between multiple species. Phytophthora polonica had the most unique compounds and was the least similar of all the species examined. The inoculated seedlings had qualitatively different volatile profiles and could be distinguished from the healthy controls by the presence of isokaurene, anisole, and a mix of three unknown compounds. This study supports the notion that volatiles are suitable for screening plant material, detecting tree pathogens, and differentiating between healthy and diseased material. [ABSTRACT FROM AUTHOR]

An online survey was conducted to show that most respondents preferred sports drinks with sweet and fruity characteristics. Eleven sports drinks with higher consumers' preferences were further selected for aroma and taste evaluation. Temporal dominance of sensations analysis showed that fruity and fresh attributes were dominant, while sour and fruity sweet were dominant tastes during consumption. β-Damascenone, β-ionone, and linalool contributing to floral perception, γ-decalactone, ethyl cinnamate, and isoamyl acetate contributing to fruity perception, and menthol contributing to fresh perception were confirmed by odor activity value analysis. Running affected the nasal air flow and the saliva secretion, resulting in the flavor perception changing from fruity sweet, sweet, and fruity to sour because the recognition threshold decreased for sweet, fruity, floral, and fresh flavors and increased for saltiness, astringency, and sour tastes. [ABSTRACT FROM AUTHOR]

Wall paintings are integral to cultural heritage and offer rich insights into historical and religious beliefs. There exist various wall painting techniques that pose challenges in binder and pigment identification, especially in the case of egg/oil-based binders. GC-MS identification of lipidic binders relies routinely on parameters like the ratios of fatty acids within the plaster. However, the reliability of these ratios for binder identification is severely limited, as demonstrated in this manuscript. Therefore, a more reliable tool for effective differentiation between egg and oil binders based on a combination of diagnostic values, specific markers (cholesterol oxidation products), and PCA is presented in this study. Reference samples of wall paintings with egg and linseed oil binders with six different pigments were subjected to modern artificial ageing methods and subsequently analysed using two GC-MS instruments. A statistically significant difference (at a 95% confidence level) between the egg and oil binders and between the results from two GC-MS instruments was observed. These discrepancies between the results from the two GC-MS instruments are likely attributed to the heterogeneity of the samples with egg and oil binders. This study highlights the complexities in identifying wall painting binders and the need for innovative and revised analytical methods in conservation efforts. [ABSTRACT FROM AUTHOR]

This study focuses on the behavior of volatile organic compounds in beef after irradiation with 1 MeV accelerated electrons with doses ranging from 0.25 kGy to 5 kGy to find reliable dose-dependent markers that could be used for establishing an effective dose range for beef irradiation. GC/MS analysis revealed that immediately after irradiation, the chemical yield and accumulation rate of lipid oxidation-derived aldehydes was higher than that of protein oxidation-derived aldehydes. The nonlinear dose-dependent relationship of the concentration of volatile organic compounds was explained using a mathematical model based on the simultaneous occurrence of two competing processes: decomposition of volatile compounds due to direct and indirect action of accelerated electrons, and accumulation of volatile compounds due to decomposition of other compounds and biomacromolecules. A four-day monitoring of the beef samples stored at 4 °C showed that lipid oxidation-derived aldehydes, protein oxidation-derived aldehydes and alkanes as well as alcohol ethanol as an indicator of bacterial activity were dose-dependent markers of biochemical processes occurring in the irradiated beef samples during storage: oxidative processes during direct and indirect action of irradiation, oxidation due to the action of reactive oxygen species, which are always present in the product during storage, and microbial–enzymatic processes. According to the mathematical model of the change in the concentrations of lipid oxidation-derived aldehydes over time in the beef samples irradiated with different doses, it was found that doses ranging from 0.25 kGy to 1 kGy proved to be most effective for beef irradiation with accelerated electrons, since this dose range decreases the bacterial content without considerable irreversible changes in chemical composition of chilled beef during storage. [ABSTRACT FROM AUTHOR]

Considering Korea's gradual shift toward an aging society, consumer interest in compounds with physiological benefits, including antioxidant and anticancer effects, has surged. This study explored the potential of Tetragonia tetragonoides (Pall.) Kunze, commonly known as New Zealand Spinach (NZS), a halophyte with reported health benefits, including efficacy in treating gastrointestinal diseases, high blood pressure, diabetes, and obesity. This study also introduced a novel callus culture system for NZS, allowing for the rapid in vitro production of secondary metabolites. Optimal callus induction (100%) and biomass production (0.416 g) were achieved by adding 2.0 mg·L−1 6-BA (6-Benzylaminopurine) and 0.5 mg·L−1 2,4-D (2,4-Dichlorophenoxyacetic acid) among five auxin and cytokinin combinations. Two distinct callus types, TGC [TDZ (Thidiazuron)-supplemented Green Callus] and TNYC [TDZ + NAA (Naphthalene acetic acid)-supplemented Yellow Callus], were identified, each with unique characteristics. The calli showed total phenolic and flavonoid contents comparable to those of NZS leaves grown in the greenhouse. An expression analysis of six genes (CHS, CHI, F3H, F3′H, FLS, and DFR) involved in the kaempferol biosynthesis revealed an enhanced flavonoid biosynthesis-related gene expression in TGC, emphasizing its potential for compound production. GC-MS analysis identified distinct compound profiles in TGC and TNYC, with 2,3-butanediol and succinic acid being the predominant compounds among the nine and forty-four components, respectively. These calli offer a stable supply of functional compounds and present an environmentally sustainable solution. The derived callus culture system is anticipated to contribute to the development of healthy functional foods or pharmaceuticals from halophyte NZS. [ABSTRACT FROM AUTHOR]

Dispersive liquid–liquid microextraction, an environmentally friendly extraction technique, followed by gas chromatography–mass spectrometry operating in selected ion monitoring (SIM) mode, is here presented for the simultaneous determination of two anticonvulsant drugs in plasma, Topiramate and Carbamazepine. Experimental parameters affecting the recovery of the proposed extraction method, such as the extraction and dispersion solvent, the extraction and dispersion volume, the sample amount, the pH of the aqueous phase, the ultrasound time, the centrifugation time and ionic strength, were investigated. The limits of detection for Topiramate and Carbamazepine were 0.01 and 0.025 µg mL−1, and the limits of quantification were 0.025 µg mL−1 and 0.05 µg mL−1, respectively. The method is shown to be selective, accurate, precise and linear over the concentration ranges of 0.025–8 µg mL−1 for Topiramate and 0.05–3 µg mL−1 for Carbamazepine. The extraction recovery of the analytes ranged from 91.5% to 113.9%. The analytical method was successfully applied to real plasma samples received by the Forensic Toxicology Service of the Forensic Science Institute of Santiago de Compostela. [ABSTRACT FROM AUTHOR]

In general, females present with stronger immune responses than males, but scarce data are available on sex-specific differences in immunometabolism. In this study, we characterized porcine peripheral blood mononuclear cell (PBMC) and granulocyte energy metabolism using a Bayesian 13C-metabolic flux analysis, which allowed precise determination of the glycolytic, pentose phosphate pathway (PPP), and tricarboxylic acid cycle (TCA) fluxes, together with an assessment of the superoxide anion radical (O2•−) production and mitochondrial O2 consumption. A principal component analysis allowed for identifying the cell type-specific patterns of metabolic plasticity. PBMCs displayed higher TCA cycle activity, especially glutamine-derived aspartate biosynthesis, which was directly related to mitochondrial respiratory activity and inversely related to O2•− production. In contrast, the granulocytes mainly utilized glucose via glycolysis, which was coupled to oxidative PPP utilization and O2•− production rates. The granulocytes of the males had higher oxidative PPP fluxes compared to the females, while the PBMCs of the females displayed higher non-oxidative PPP fluxes compared to the males associated with the T helper cell (CD3+CD4+) subpopulation of PBMCs. The observed sex-specific differences were not directly attributable to sex steroid plasma levels, but we detected an inverse correlation between testosterone and aldosterone plasma levels and showed that aldosterone levels were related with non-oxidative PPP fluxes of both cell types. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) are recognized as carcinogens and mutagenic food contaminants that threaten public health. As for food safety aspects, control of these contaminants in processed and fatty food is necessary. In this study, eleven factors were screened by the Plackett–Burman design, and four variables were chosen to optimize with the central composite design (CCD) for the improvement of extraction and cleanup procedures of these food contaminants. The optimized variables include 5 g of sample, 2 mL mixture of 2/2/1 ethyl acetate/acetone/isooctane, 1.6 g of ammonium formate, 0.9 g of sodium chloride, and 0.25 g of sorbent Z-Sep+. A 5 min cleanup vortex time with the spike calibration curve strategy, analyzed by gas chromatography–mass spectrometry (GC-MS), led to the validated limits of quantification (LOQs) for 16 PAHs and 36 PCBs of 0.5–2 and 0.5–1 ng/g, respectively, and recoveries of 72–120%, with an average relative standard deviation (%RSD) of 17, for PAHs, and 80–120%, with an %RSD of 3, for PCBs. The method introduces excellent accuracy, precision, and efficiency, and minimizes matrix effects, and ensures a control procedure, adopted with international standards, for food authorities to determine the contaminants of interest in processed meat, and consequently, prevent food-borne disease to improve public health indices. [ABSTRACT FROM AUTHOR]

The pentose phosphate pathway (PPP) plays a key role in the cellular regulation of immune function; however, little is known about the interplay of metabolic adjustments in granulocytes, especially regarding the non-oxidative PPP. For the determination of metabolic mechanisms within glucose metabolism, we propose a novel set of measures for 13C-metabolic flux analysis based on ex vivo parallel tracer experiments ([1,2-13C]glucose, [U-13C]glucose, [4,5,6-13C]glucose) and gas chromatography–mass spectrometry labeling measurements of intracellular metabolites, such as sugar phosphates and their fragments. A detailed constraint analysis showed that the permission range for net and irreversible fluxes was limited to a three-dimensional space. The overall workflow, including its Bayesian flux estimation, resulted in precise flux distributions and pairwise confidence intervals, some of which could be represented as a line due to the strength of their correlation. The principal component analysis that was enabled by these behaviors comprised three components that explained 99.6% of the data variance. It showed that phagocytic stimulation reversed the direction of non-oxidative PPP net fluxes from ribose-5-phosphate biosynthesis toward glycolytic pathways. This process was closely associated with the up-regulation of the oxidative PPP to promote the oxidative burst. [ABSTRACT FROM AUTHOR]

Infections caused by Candida albicans (C. albicans) and increasing resistance to commonly used drugs lead to a variety of mucosal diseases and systemic infectious diseases. We previously confirmed that the essential oil of Clausena lansium (Lour.) Skeels seeds (CSEO) had antifungal activity against C. albicans, but the detailed mechanism between the chemical components and antifungal activity is unclear. In this study, a quantitative analysis of five volatile components of CSEO, including sabinene, α-phellandrene, β-phellandrene, 4-terpineol, and β-caryophyllene, was carried out using the gas chromatography–mass spectrometry (GC–MS) method. Both the broth dilution and kinetic growth methods proved that the antifungal activity of CSEO against fluconazole-resistant C. albicans was better than that of its main components (sabinene and 4-terpineol). To further investigate the inhibitory mechanism, the transcriptional responses of C. albicans to CSEO, sabinene, and 4-terpineol treatment were determined based on RNA-seq. The Venn diagram and clustering analysis pattern of differential expression genes showed the mechanism of CSEO and 4-terpineol's anti-C. albicans activity might be similar from the perspective of the genes. Functional enrichment analysis suggested that CSEO regulated adherence-, hyphae-, and biofilm-formation-related genes, which may be CSEO's active mechanism of inhibiting the growth of fluconazole-resistant C. albicans. Overall, we preliminarily revealed the molecular mechanism between the chemical components and the antifungal activity of CSEO against C. albicans. This study provides new insights to overcome the azole resistance of C. albicans and promote the development and application of C. lansium (Lour.) Skeels seeds. [ABSTRACT FROM AUTHOR]

The tomato potato psyllid (TPP) Bactericera cockerelli is a serious pest of the Solanaceae family. The management of this pest using synthetic pesticides is problematic because of the development of pesticide resistance and environmental concerns including impacts on non-target organisms. The predatory bug Engytatus nicotianae has recently been identified as a useful biocontrol agent for TPP in greenhouses. The soil fungus Trichoderma Pers. is commonly used as a plant growth enhancer and biocontrol agent against phytopathogenic fungi. Therefore, there could be advantages associated with the combined use of these biocontrol agents. Some reports in other systems suggest that Trichoderma inoculation may alter the behaviour of pests and their natural enemies by modifying plant defence metabolites such as volatile organic compounds (VOCs). For this reason, this study aimed to investigate the individual and combined efficacy of these biocontrol agents (i.e., Trichoderma atroviride and E. nicotianae) against TPP in greenhouse grown tomatoes (Solanum lycopersicum cv. Merlice). To this end, we compared the effect of each biocontrol agent and their combination on TPP abundance across different developmental stages (egg, nymphs, adults) and the number of infested leaves. We also investigated plant VOC emissions under the different treatments. Across all measured TPP stages, the treatments tested (E. nicotianae alone, T. atrovirdae alone, and T. atrovirdae + E. nicotianae) significantly reduced mean TPP counts relative to the control, and no significant differences were observed in VOC emissions among treatments. Overall, T. atrovirdae alone was less effective than E. nicotianae alone and its combination with T. atrovirdae in suppressing TPP populations. However, the combined use of Trichoderma + E. nicotianae did not show significant advantages over the use of E. nicotianae alone in controlling TPP. Therefore, their combined use needs to be further assessed in light of other advantages of Trichoderma to the crop (e.g., growth promotion or pathogen defence). [ABSTRACT FROM AUTHOR]

The Korean mountains are home to the Korean red pine (Pinus densiflora). Pine needle oil has been used as a food additive and a traditional herbal medicine; however, any health-related properties of its trunk oil remain unknown. Herein, we assessed antibacterial and antiviral properties of essential oil extracted from the trunk of P. densiflora. Th extracted oil was hydrodistilled using a Clevenger apparatus and analyzed using gas chromatography–mass spectrometry. The antimicrobial activity of the oil was tested using the microbroth dilution technique against 10 bacterial species (6 g-positive and 4 g-negative) and fungi. The extract exerted strong antimicrobial activity against Vibrio parahaemolyticus, Bacillus cereus, Listeria monocytogenes, Propionibacterium acnes, and Malassezia furfur (minimum inhibitory concentration = 10 mL/L). Additionally, it exhibited dose-dependent activity against influenza virus A and feline coronavirus. Furthermore, among 20 identified constituents accounting for 98.7% of the oil contents, the major components included 3-cyclohexene-1-methanol (10.12%), 2-(4-methylcyclohexyl)-2-propanol (9.09%), fenchone (8.14%), O-isopropyltoluene (6.35%), and isothymol methyl ether (6.14%). The P. densiflora trunk essential oil showed antibacterial and antiviral activities that depended on its chemical composition and the microbial strains tested herein. The essential oil can be used as an antimicrobial agent and disinfectant. [ABSTRACT FROM AUTHOR]

Several methods have been used to determine the volatile organic compounds emitted by Ophrys orchids. The use of different methods results in incomparable data. Solid-phase microextraction (SPME) has not been used extensively on Ophrys orchids. The main components found in the SPME analysis of the scent in Ophrys orchids were as follows: O. apifera: benzyl benzoate and α-copaene; O. crabronifera subsp. biscutella: pentadecane, heptadecane, and nonadecane; O. bertolonii subsp. bertolonii: pentadecane and heptadecane; O. passionis subsp. garganica: i-propyl palmitate and heptadecane; O. holosericea subsp. apulica: α-copaene, pentadecane, and heptadecane; O. lacaitae: α-copaene, pentadecane, and heptadecane; O. bombyliflora: cyclosativene, pentadecane, and ethyl dodecanoate; O. insectifera: 8-heptadecene and pentadecane; O. lutea: heptadecane and docosane; O. tenthredinifera subsp. neglecta: α-copaene, caryophyllene, and i-propyl palmitate. [ABSTRACT FROM AUTHOR]

The study of exogenous metabolites of algae-bacterial communities in the laboratory accumulative culture obtained from natural river water was conducted using gas chromatography-mass spectrometry. Exometabolites of the algae-bacterial community (including microalgae and cyanobacteria) in the culture medium were represented by saturated, unsaturated, and aromatic hydrocarbons, carboxylic acids, phenolic, and terpene compounds and their derivatives. Possible biological activities of the discovered exometabolites are considered. The study has demonstrated that an increase in the number of main groups of microorganisms, along with changes in the composition of algae and cyanobacteria, are responsible for the increase in the composition and concentration of metabolites in the microecosystem's culture medium after one month of cultivation. The presence of octacosane in high concentration (0.0603 mg/L; 23.78% of the total content of low molecular weight organic compounds) by the end of exposure accumulative culture is associated with the strong development of the cyanobacterium Gloeocapsa sp. in the presence of diatom algae of the genus Navicula and green algae of the genera Chlorella and Scenedesmus. Due to the need to comprehend the ecological and biochemical mechanisms of the formation and functioning of algae-bacterial communities, as well as to predict potential paths of transformation and evolution of aquatic ecosystems, the specificity of exometabolite complexes of algae and microorganisms, as well as their allelopathic and other biochemical interactions in freshwater ecosystems, requires further serious study. [ABSTRACT FROM AUTHOR]

(1) Background: Preservatives may pose a potential threat to human health. To ensure food safety, this study has devised a method that concurrently detects a dozen preservatives (acetic acid, propionic acid, dehydroacetic acid, benzoic acid, sorbic acid, dimethyl fumarate, methyl parahydroxybenzoate, ethyl parahydroxybenzoate, propyl parahydroxybenzoate, isopropyl parahydroxybenzoate, butyl parahydroxybenzoate, and isobutyl parahydroxybenzoate) in pastry, utilizing gas chromatography–mass spectrometry. (2) Methods: The pastry samples were acidified with hydrochloric acid, extracted with acetonitrile via vortexing, purified by hexane and saturated with sodium chloride solution to remove lipids and impurities, and then concentrated via nitrogen blowing. The method was then quantitatively analyzed using GC-MS with the internal standard method after methanol re-dissolution. (3) Results: The results showed that the content of the 12 preservatives had good linearity within the range of 1.0–50 μg/mL, with correlation coefficients all greater than 0.99. The method detection limit was 0.04–2.00 mg/kg and the quantification limit was 0.12–6.67 mg/kg. The average recovery rates of the samples at three different spiked concentrations of low, medium, and high were 70.18–109.22%, and the relative standard deviations were 1.82–9.79% (n = 6). (4) Conclusions: This method requires a small amount of sample, has high sensitivity, and is simple and fast to operate, making it suitable for the simultaneous determination of 12 preservatives in pastry. This approach contributes to the effective surveillance and regulation of preservative usage in pastries, thereby safeguarding public well-being. [ABSTRACT FROM AUTHOR]

The investigation of novel sample matrices in the forensic sciences offers several possible advantages, such as allowing for results to be obtained in cases where common sample types are absent. This review focuses on the application of gas chromatography and gas chromatography–mass spectrometry (GC-MS) for the determination of drugs in alternative sample matrices, including hair, sweat, meconium, breast milk, and vitreous humour. Less common sample types are also reported including air, cerumen, insects, and their larvae and pupae. The application of pyrolysis GC-MS (Py GC-MS) is also reviewed, showing the possibility of determining high molecular weight drugs which would commonly be unattainable by GC-MS. The application of Py GC-MS for the simulation and investigation of the underlying chemistry and the products formed in the smoking of drugs is also reported. [ABSTRACT FROM AUTHOR]

Ankylosing spondylitis (AS) is a type of chronic rheumatic immune disease, and the crucial point of AS treatment is identifying the correct stage of the disease. However, there is a lack of effective diagnostic methods for AS staging. The primary objective of this study was to perform an untargeted metabolomic approach in AS patients in an effort to reveal metabolic differences between patients in remission and acute stages. Serum samples from 40 controls and 57 AS patients were analyzed via gas chromatography–mass spectrometry (GC–MS). Twenty-four kinds of differential metabolites were identified between the healthy controls and AS patients, mainly involving valine/leucine/isoleucine biosynthesis and degradation, phenylalanine/tyrosine/tryptophan biosynthesis, glutathione metabolism, etc. Furthermore, the levels of fatty acids (linoleate, dodecanoate, hexadecanoate, and octadecanoate), amino acids (serine and pyroglutamate), 2-hydroxybutanoate, glucose, etc., were lower in patients in the acute stage than those in the remission stage, which may be associated with the aggravated inflammatory response and elevated oxidative stress in the acute stage. Multiple stage-specific metabolites were significantly correlated with inflammatory indicators (CRP and ESR). In addition, the combination of serum 2-hydroxybutanoate and hexadecanoate plays a significant role in the diagnosis of AS stages. These metabolomics-based findings provide new perspectives for AS staging, treatment, and pathogenesis studies. [ABSTRACT FROM AUTHOR]

Currently, the leaves of the hop plant (Humulus lupulus L.) are an unexploited and still little-investigated agricultural by-product. In our study, with the aim of exploring the metabolome of dried hop leaves (Chinook cultivar), a metabolomic approach was applied using multiple analytical tools such as SPME/GC–MS, GC–MS, PTR-ToF-MS, and NMR to identify the secondary metabolites. The obtained results showed the presence of a high number of components belonging to different chemical classes. In fact, thanks to the multi-methodological approach, volatile organic compounds (VOCs) with low molecular weight, terpenic compounds, fatty acids, sugars, amino acids, organic acids, and alcohols have been detected and identified. Among the revealed terpenes in the untreated matrix, the sesquiterpenes α-humulene, β-caryophyllene, and α-copaene were the most abundant. Among the saturated and unsaturated fatty acids, palmitic and linolenic acids, respectively, were those with the highest relative percentages. Particularly relevant was the sugar content, where sucrose was the main exponent while glutamate and asparagine were the principal detected amino acids. Conversely, alcohols and organic acids were the least abundant compound classes, and xanthohumol was also identified in the methanolic extract. [ABSTRACT FROM AUTHOR]

Silver carp (Hypophthalmichthys molitrix) is normally cooked at a high temperature. In order to explore the effects of cooking methods on the protein nutritional values and volatile flavor substances of silver carp meat, the meat was fried, roasted and steamed, and its contents were determined in relation to moisture, protein, fat, ash, amino acids and volatile flavor substances. The results show that the moisture content of cooked silver carp can be ranked as follows: raw > steamed > roasted > fried. The protein content order of the four samples can be ranked: fried > roasted > raw > steamed. The ash and the fat contents of the four samples showed similar significant (p < 0.05) differences, in the order of fried > roasted > steamed > raw. The contents of all the amino acids in the fried meat were significantly (p < 0.05) higher than the contents in others, and the frying, roasting and steaming processes improved the umami taste (supported by the increased content of glutamate and aspartate) and the protein nutritional value (supported by the amino acid score, essential amino acid index and protein efficiency ratio) of the silver carp meat. A total of 51 compounds were detected in the fried, roasted and steamed meat. Frying and roasting reduced the fishy flavor of this meat. The odor activity value (OAV) indicated that methanethiol, 1-octen-3-ol and 2-heptanone were the key flavor chemicals in raw meat. Hexanal, propionaldehyde, octanal, nonanal, decanal, 1-octen-3-ol and 2-heptanone were key to the flavor of fried meat. Pentanal, decanal, methyl mercap-tan and 1-octen-3-ol contributed greatly to the overall flavor of the roasted meat. Nonanal, methylmercaptan and 1-octene-3-ol had strong effects on the flavor of the steamed silver carp meat. [ABSTRACT FROM AUTHOR]

The human body releases numerous volatile organic compounds (VOCs) through tissues and various body fluids, including breath. These compounds form a specific chemical profile that may be used to detect the colorectal cancer CRC-related changes in human metabolism and thereby diagnose this type of cancer. The main goal of this study was to investigate the volatile signatures formed by VOCs released from the CRC tissue. For this purpose, headspace solid-phase microextraction gas chromatography-mass spectrometry was applied. In total, 163 compounds were detected. Both cancerous and non-cancerous tissues emitted 138 common VOCs. Ten volatiles (2-butanone; dodecane; benzaldehyde; pyridine; octane; 2-pentanone; toluene; p-xylene; n-pentane; 2-methyl-2-propanol) occurred in at least 90% of both types of samples; 1-propanol in cancer tissue (86% in normal one), acetone in normal tissue (82% in cancer one). Four compounds (1-propanol, pyridine, isoprene, methyl thiolacetate) were found to have increased emissions from cancer tissue, whereas eleven showed reduced release from this type of tissue (2-butanone; 2-pentanone; 2-methyl-2-propanol; ethyl acetate; 3-methyl-1-butanol; d-limonene; tetradecane; dodecanal; tridecane; 2-ethyl-1-hexanol; cyclohexanone). The outcomes of this study provide evidence that the VOCs signature of the CRC tissue is altered by the CRC. The volatile constituents of this distinct signature can be emitted through exhalation and serve as potential biomarkers for identifying the presence of CRC. Reliable identification of the VOCs associated with CRC is essential to guide and tune the development of advanced sensor technologies that can effectively and sensitively detect and quantify these markers. [ABSTRACT FROM AUTHOR]

Numerous plants of medicinal value grow on Hainan Island (China). Given the lack of knowledge on the phytochemical and pharmacological properties of Michelia shiluensis Chun and Y. F. Wu (M. shiluensis), the application of natural antioxidants and antimicrobials in the food industry has attracted increasing interest. This study aimed to compare the chemical composition, free-radical-scavenging capacity, and antibiosis of aqueous extracts of the fresh and dried leaves of M. shiluensis. The aqueous extract of the leaves of M. shiluensis was obtained using steam distillation, and its chemical components were separated and identified via gas chromatography–mass spectrometry (GC-MS). The free-radical-scavenging capacity and antibiosis were determined. Further, 28 and 20 compounds were isolated from the fresh leaf aqueous extract of M. shiluensis (MSFLAE) and dried leaf aqueous extract of M. shiluensis (MSDLAE), respectively. The free-radical-scavenging capacity of MSFLAE and MSDLAE was determined by the 2,2-diphenyl-1 picrylhydrazyl (DPPH) method, which was 43.43% and 38.74%, respectively. The scavenging capacity of MSFLAE and MSDLAE determined by the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate (ABTS)) method was 46.90% and 25.99%, respectively. The iron ion reduction capacity of MSFLAE and MSDLAE was determined by the ferric-reducing antioxidant power (FRAP) method as 94.7 and 62.9 μmol Fe2⁺/L, respectively. This indicated that the two leaf aqueous extracts had a certain free-radical-scavenging capacity, and the capacity of MSFLAE was higher than that of MSDLAE. The antibiosis of the two leaf aqueous extracts on the three foodborne pathogenic bacteria was low, but the antimicrobial effects on Gram-positive bacteria were better than those on Gram-negative bacteria. The antibiosis of MSFLAE on Escherichia coli and Staphylococcus aureus was greater than that of MSDLAE. Finally, MSFLAE and MSDLAE both had certain free-radical-scavenging capacities and antibiosis, confirming that the use of this plant in the research and development of natural antioxidants and antibacterial agents was reasonable. Plant aqueous extracts are an essential source of related phytochemistry and have immense pharmacological potential. [ABSTRACT FROM AUTHOR]

A simple, effective, and highly sensitive analytical approach was created and applied in this study for the accurate measurement of three β2-agonist residues (clenbuterol, salbutamol, and ractopamine) in meat samples. In the course of the experiment, new adsorbent molecular sieves (ZMS)@nitrogen-doped carbon quantum dots (N-CQDs) composite materials were synthesized with the aid of hydrothermal synthesis. The composite adsorbent materials were prepared and characterized through scanning electron microscopy, transmission electron microscope, X-ray photoelectron spectroscopy, fluorescence, and zeta potential. Four determinants affecting the extraction and elution's efficiency, such as the amount of adsorbent, the extraction time, desorption time, and the amount of extraction salt, were substantially optimized. The analytes were quantified by gas chromatography–mass spectrometry. Final results of the methodological validation reflected that the ZMS@N-CQDs composite materials were able to adsorb three β2-agonist residues well and had good reproducibility. In the meantime, all analytes indicated good linearity with coefficient of determination R2 ≥ 0.9908. The limit of detection was 0.7–2.0 ng·g−1, the limit of quantification varied from 2.4 to 5.0 ng·g−1, the precision was lower than 11.9%, and the spiked recoveries were in the range of 79.5–97.8%. To sum up, the proposed approach was quite effective, reliable, and convenient for the simultaneous analysis of multiple β2-agonist residues. Consequently, this kind of approach was successfully applied for the analysis of such compounds in meat samples. [ABSTRACT FROM AUTHOR]

The aroma of vanilla pods is mainly derived from vanillin. Microbial biotransformation reactions of vanillin precursors yield "natural" vanillin-related aroma metabolites. In this study, we coated vanilla pods with three edible microorganisms and observed the changes in tissues with a laser scanning microscope during early curing. In addition, the conducted volatile components analysis using gas chromatography-mass spectrometry (GC-MS) with ethanol extracts to investigate the differences in the aroma components of coated and uncoated microbial vanilla pods and to identify the correlation between processing and the oily luster of pods. The results demonstrate that the oily luster on the surface of vanilla pods coated with Bacillus subtilis subsp. subtilis is one of the necessary conditions for a high-quality vanilla product. Eight categories of compounds were found in the ethanol extract of vanilla pods. A total of 69 volatile components were analyzed. Different microbial species significantly influenced the volatile components, with 31 compounds not found in the control group. Furthermore, 30 odor and aroma compounds were identified. This study reveals the role of edible microbial coatings in enhancing the natural aroma of vanilla pods and offers possibilities for the development of new and unique vanilla aroma profiles. [ABSTRACT FROM AUTHOR]

To identify the volatile flavor components in mustard paste (MP), the volatile compounds in seven MPs available on the market were isolated and analyzed by headspace solid-phase microextraction combined with gas chromatography–mass spectrometry. A total of 27 volatile constituents were found by mass spectra and retention index compared to the data obtained from reference compounds or the related literature and databases; these compounds included nine esters, three sulfur-containing compounds, two nitriles, three ketones, three alkenes, and seven other compounds. Of the 27 compounds, 6 compounds came from the turmeric added to MPs. Among the components detected, some compounds derived from AITC were allyl thiocyanate, carbon disulfide, allyl mercaptan, diallyl sulfide, and diallyl disulfide. The results obtained provide a better and comprehensive recognition of the volatile flavor compounds in MPs, and have some reference values for developing and applying isothiocyanate compounds. [ABSTRACT FROM AUTHOR]

In order to study the effect of both greenhouse and forest cultivating environments on Stropharia rugosoannulata, its volatile aroma compounds were measured by a headspace solid phase micro extractions—gas chromatograph—mass spectrometer (SPME–GC–MS). The optimal adsorption temperature was 75 °C and the optimal adsorption time was 40 min. A total of 36 volatile aroma compounds were identified by GC–MS, including 8 aldehydes, 2 ketones, 4 alcohols, 15 alkenes, and 4 alkanes. Hexanal, 3-Octanone, 2-Undecanone, (E)-Nerolidol, and (Z)-β-Farnesene made great aromatic contributions. Among them, Hexanal, 3-Octanone, 2-Undecanone were the key aroma compounds for which odor activity values (OAVs) were more than 1. (E)-Nerolidol showed odor modification in the forest samples and showed a key aroma effect in greenhouse samples. (Z)-β-Farnesene showed odor modification in greenhouse samples. 3-Octanone was the largest contributing compound for which the OAV was more than 60. The total content of volatile aroma compounds first increased and then decreased with growth time; it reached the highest level at 48 h: 2203.7 ± 115.2 μg/kg for the forest environment and 4516.6 ± 228.5 μg/kg for the greenhouse environment. The aroma was the most abundant at this time. All samples opened their umbrella at 84 h and become inedible. Principal component analysis (PCA), hierarchical cluster analysis (HCA), and orthogonal partial least squares discriminant analysis (OPLS–DA) were combined to analyze the aroma difference of S. rugosoannulata under two cultivation modes. PCA and HCA could effectively distinguish the aroma difference in different growth stages. Under different culturing methods, the aroma substances and their changes were different. The samples were divided into two groups for forest cultivation, while the samples were divided into three groups for greenhouse cultivation. At the end of growth, the aroma of S. rugosoannulata with the two cultivation modes was very similar. OPLS–DA clearly distinguished the differences between the two cultivation methods; 17 key aroma difference factors with variable importance projection (VIP) > 1 were obtained from SPLS–DA analysis. [ABSTRACT FROM AUTHOR]

Kargil is a cold desert with hostile ecological conditions such as low temperature and precipitation, as well as difficult terrains. However, several wild mushrooms thrive well under such an extreme environment. Despite their abundance, the chemical composition of indigenous mushrooms has not been explored. This study aimed to assess the potential of two wild edible mushrooms from Kargil, Lactarius drassinus and Lactarius controversus, as food supplements by evaluating their nutritional and nutraceutical properties. Nutritional attributes such as total protein, available carbohydrates, soluble sugars, and vitamins were found to be high in the mushroom species. Furthermore, high mineral accumulation and relatively lower antinutrient concentrations resulted in higher bioavailabilities of Zn, Fe, Ca, and Mg. Gas-chromatography–mass-spectrometry-based metabolite profiling revealed that although the two mushroom species showed similar metabolite compositions, their relative concentrations differed. Sugars were the predominant compounds identified in both the species, with sugar alcohols being the major contributor. The second most abundant class of compound in L. drassinus was amino acids, with 5-oxoproline as the major contributor. On the other hand, fatty acids were the second most abundant compounds in L. controversus, with high oleic and linoleic acid concentrations. In the ultra-performance-liquid-chromatography-based quantification of phenolic compounds, chlorogenic acid was found to be highest in in terms of its concentration in both the mushrooms studied, followed by quercetin dihydrate and gallic acid in L. drassinus and L. controversus, respectively. Moreover, high antioxidant activities attributable to their high phenol, flavonoid, and carotenoid concentrations were observed. Overall, the two mushrooms offer well-balanced sources of nutritional and nutraceutical compounds, making them healthy foods. [ABSTRACT FROM AUTHOR]

Barleria albostellata (Acanthaceae) is a shrub located in South Africa and is relatively understudied. However, plants within this genus are well known for their medicinal and ethnopharmacological properties. This study aimed to characterise the phytochemical compounds and antibacterial efficacies of B. albostellata. Phytochemical analysis, fluorescence microscopy and gas chromatography-mass spectrometry (GC-MS) analysis were performed to determine the composition of compounds that may be of medicinal importance. Crude leaf and stem extracts (hexane, chloroform and methanol) were subjected to an antibacterial analysis against several pathogenic microorganisms. The qualitative phytochemical screening of leaf and stem extracts revealed the presence various compounds. Fluorescence microscopy qualitatively assessed the leaf and stem powdered material, which displayed various colours under bright and UV light. GC-MS chromatograms represents 10–108 peaks of various compounds detected in the leaf and stem crude extracts. Major pharmacologically active compounds found in the extracts were alpha-amyrin, flavone, phenol, phytol, phytol acetate, squalene and stigmasterol. Crude extracts positively inhibited Gram-positive and Gram-negative bacteria. Significance was established at p < 0.05 for all concentrations and treatments. These results indicate that the leaves and stems of B. albostellata are rich in bioactive compounds, which could be a potential source of antibacterial agents for treating various diseases linked to the pathogenic bacteria studied. Future discoveries from this plant could advance the use of indigenous traditional medicine and provide novel drug leads. [ABSTRACT FROM AUTHOR]

Sichuan black tea (SCBT) is well known for its pleasant sweet and citrus-like aroma. However, the origin of this distinctive aroma remains unknown. Herein, the aroma characteristics of SCBT during processing were comprehensively investigated by sensory evaluation, gas chromatography–mass spectrometry, and odor activity value (OAV). A total of 764 volatile compounds were identified and grouped into 16 categories. Notably, terpenoids, heterocyclic compounds, and esters comprised 19.35%, 16.34%, and 16.08% of total volatile compounds produced during processing, respectively. Moreover, the fermentation and second drying stages exhibited the most striking variations, with 99 and 123 volatile compounds being significantly altered. In addition, the OAV analysis led to the identification of 17 volatile compounds as key differential volatile compounds (DVCs): these included citronellol, linalool, p-cymene, (E)-linalool oxide (furanoid), etc. Among them, (3Z)-3,7-dimethylocta-1,3,6-triene and D-limonene that exhibited a grassy aroma decreased during processing, while linalool and p-cymene that had a sweet and citrus aroma increased. Thus, based on a correlation between characteristic aroma data and descriptive sensory analysis data, linalool and p-cymene were identified as the primary volatiles responsible for the sweet and citrus-like aroma. In conclusion, this study improves our understanding of the components and formation mechanism of the sweet and citrus-like aroma of SCBT. [ABSTRACT FROM AUTHOR]

The solid-state fermentation process of strongly flavored Baijiu is complicated by the co-fermentation of many different microorganisms in the fermentation pools. The traditional fermentation pools of strong flavor Baijiu are sealed with mud, and this sealed-pit mud is not easy to maintain; therefore, the pit cap is prone to cracks and to caving in. The destruction of the sealed-pit mud may lead to instability in the composition and an abundance of microorganisms in the fermentation process that results in fluctuations of product quality. Thus, the production method of replacing the mud cap with a new steel cap is gradually attracting the attention of scientific and technical workers in the industry. However, so far, there have been relatively few reports on the use of steel lids for sealing pits for fermentation and brewing. In this study, the volatile flavor components of 270 Baijiu samples from mud-sealing and steel-sealing pits of a Chinese Baijiu distillery were studied qualitatively and quantitatively using Gas Chromatography–Mass Spectrometry (Abbreviated as GC-MS). Our statistical methods included Hierarchical Cluster Analysis (Abbreviated as HCA), Principal Component Analysis (Abbreviated as PCA), and Discriminant Analysis (Abbreviated as DA). A statistical analysis was carried out on the yield of strongly flavored Baijiu, and we made a comprehensive evaluation of the Baijiu produced under the two pit-sealing modes with regard to flavor and economic efficiency. The yield of strong flavored Baijiu was 6.7% higher with steel-sealing pits compared with mud-sealing pits. Cluster analysis categorized the strongly flavored Baijiu samples into two categories initially: (1) samples produced using mud-sealing pits and (2) samples using steel-sealing pits. Our analysis also indicated that the 28 compounds used for quantification were selected correctly. Surprising to the experimental staff, the overall score for the steel-sealing pits was greater than that of the mud-sealing pits based on PCA. Using DA, the prediction results were 100% accurate. In summary, through a comparative analysis of the flavor and yield, which are the two main factors that affect the quality of Baijiu in a distillery, and systematic combination at both experimental and theoretical levels, the differences between the Baijiu production by steel-sealing and the traditional mud-sealing were clear. Regardless of the impact of age, the detectable flavor components of Baijiu from the mud-steeling pits were very consistent with those of the steel-sealing pits in terms of richness or concentration. However, steel-sealing pits were significantly superior to mud-sealing pits with respect to output, consistency in quality, and cost (human and economic) savings. [ABSTRACT FROM AUTHOR]

Edible insects have recently attracted attention as an alternative sustainable protein food source. However, consumer aversion remains the major obstacle to successful implementation in the food industry due to their shape and unpleasant odor. Here, we evaluated and compared odor-active compounds from untreated Gryllus bimaculatus (UGB), hot-air dried GB at 70 °C for 10 h (AGB), freeze-dried GB (FGB), steam-heated GB at 121 °C and 14.5 psi for 15 min (SGB), and defatted GB by hexane (DFGB). Each sample was analyzed using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O). The most volatile compounds were detected in UGB, followed by SGB, DFGB, AGB, and FGB by GC-MS analysis. In GC-O analysis, fourteen compounds were identified as cricket or cricket-related odor among twenty identified compounds. Cyclododecane had the strongest cricket-related odor found only in UGB. DFGB received the lowest total scores of intensity for cricket-related odors, while SGB received the highest scores. It seems that defatting could reduce cricket-related odors. This study may provide theoretical information for the GB odors according to the four processing methods. [ABSTRACT FROM AUTHOR]

Simple Summary: Mosquitoes are not only a nuisance, but most of them pose a threat to human beings as they can transmit pathogens that are harmful and may turn fatal, such as dengue, chikungunya, and Zika. This study was carried out to evaluate the larvicidal properties of the solvent extracts from three aromatic plants, Curcuma longa (turmeric), Ocimum americanum (hoary basil), and Petroselinum crispum (parsley)—against the mosquito vector of dengue, Aedes albopictus. Thereafter, the phytochemical profiles and the cellular toxicity of the extracts were evaluated. The results indicate that the hexane extracts of O. americanum and P. crispum had the greatest larvicidal activity. Among these two, O. americanum was shown to be less toxic to African monkey kidney cells and possessed an abundant amount of methyl eugenol, which is a phytochemical with known larvicidal activities. Overall, our findings indicate that these aromatic plants, especially O. americanum, may prove to be highly promising alternatives as bioinsecticides. Despite ongoing control efforts, the mosquito population and diseases vectored by them continue to thrive worldwide, causing major health concerns. There has been growing interest in the use of botanicals as alternatives to insecticides due to their widespread insecticidal properties, biodegradability, and adaptability to ecological conditions. In this study, we investigated the larvicidal activity and cytotoxicity effects of solvent extracts from three aromatic plants—Curcuma longa (turmeric), Ocimum americanum (hoary basil), and Petroselinum crispum (parsley)—against Aedes albopictus. Subsequently, we examined the phytochemical composition of the extracts through gas chromatography–mass spectrometry (GC–MS) analysis. Results revealed that the hexane extracts of O. americanum and P. crispum exhibited the greatest larvicidal activity with the lowest median lethal concentration (LC50) values (<30 µg/mL) at 24 h post-treatment, with the former found to be significantly less toxic towards African monkey kidney (Vero) cells. The GC–MS analysis of the said extract indicated the presence of different classes of metabolites, including phenylpropanoids, very long-chain alkanes, fatty acids and their derivatives, and terpenes, with the most abundant component being methyl eugenol (55.28%), most of which, have been documented for their larvicidal activities. These findings provide valuable insights into the potential use and development of bioinsecticides, particularly from O. americanum. [ABSTRACT FROM AUTHOR]

The pine sawfly Diprion jingyuanensis Xiao and Zhang (Hymenoptera: Diprionidae) is a serious pest of Pinus tabulaeformis Carr. in the Shanxi, Gansu, and Inner Mongolia provinces in P. R. China. The sex pheromone of D. jingyuanensis was shown to be the propionate ester of 3,7-dimethyl-2-tridecanol. Virgin females contained an approximate 1:3 blend of the pheromone precursors erythro-(2S,3S,7R/S and 2R,3R,7R/S)-3,7-dimethyl-2-tridecanol and threo-(2S,3R,7R/S and 2R,3S,7R/S)-3,7-dimethyl-2-tridecanol, but the exact stereoisomers were not determined. Males responded the strongest to the propionate ester of the two threo-isomers, (2S,3R,7R) and (2S,3R,7S), in electroantennogram (EAG) recordings, followed by a significant EAG response to the (2S,3R,7R) propionate of diprionol (pheromone component of D. similis), whereas the remaining two isomers (2S,3S,7S and 2S,3S,7R) of the propionate ester of 3,7-dimethyl-2-tridecanol and the acetate of the (2S,3R,7R) isomer (one of the two pheromone components of D. pini) did not elicit any significant increase in antennal response. In the field, the strongly EAG-active (2S,3R,7R)-isomer alone was only weakly (but significantly) attractive to D. jingyuanensis males at 100 µg, while the equally EAG- active (2S,3R,7S)-isomer alone at the same loading was 8–14 times more attractive than was the (2S,3R,7R)-isomer alone. Traps baited with the same amounts of the two threo-isomers ((2S,3R,7R) and (2S,3R,7S), 100 µg + 100 µg) caught significantly more males than did traps baited with other isomers, either of the two isomers alone or other proportions of the two isomers. Thus, the (2S,3R,7S)-isomer is considered as a strong and essential sex-attractant component for D. jingyuanensis males, whereas the (2S,3R,7R)-isomer is a weak but synergistic sex-attractant. This is one of the few examples of a pine sawfly responding significantly stronger to a binary blend of stereoisomers in a synergistic fashion than to a single stereoisomer alone. [ABSTRACT FROM AUTHOR]

In this study, the flavor compounds of Camellia seed oils obtained by four processes were characterized by headspace solid phase microextraction/gas chromatography/mass spectrometry (HS-SPME/GC/MS). A variety of about 76 volatile flavor compounds were identified from all the oil samples. Of the four processing processes, the pressing process can retain a lot of volatile components. Among these, compounds nonanal and 2-undecenal were predominantly in the majority of the samples. Meanwhile, other compounds such as octyl ester formic acid, octanal and 2-nonenal (E), 3-acetyldihydro 2(3H)-furanone, (E)-2-decenal, dihydro-5-penty 2(3H)-furanone, nonanoic acid, and dodecane were also among the most consistently found compounds among the oil samples analyzed. The principal component analysis carried out to categorize the data produced seven clusters of the total oil samples based on the number of flavor compounds obtained in each sample. This categorization would lead to understanding the components which highly contributed to the characteristic volatile flavor and build up the flavor profile of Camellia seed oil. [ABSTRACT FROM AUTHOR]