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Simple Summary: National biosecurity efforts provide a set of precautions that aim to prevent the introduction and spread of harmful organisms, including non-native tree pests such as insects and disease-causing organisms. The spotted lanternfly is an example of a current biosecurity threat, which, while native to China, was discovered in US territory in 2014. Canine detection is an emerging tool in this pest detection effort; however, an important aspect of further eradication developments is to understand the odor chemistry of this insect. The goal of this study is to evaluate the headspace of lanternfly eggs via the instrumental approach of solid-phase microextraction with gas chromatograph-mass spectrometry (SPME-GC/MS). This study presents samplings of cold-killed spotted lanternfly eggs and relevant distractor samples to compare odor profiles. The developed method is a feasible approach for VOC analysis. The results indicate that lanternfly egg and cricket samples share a common VOC, dodecane, while the lanternfly egg and bark samples share anisole as a common odor volatile. This study provides an initial snapshot of the VOC makeup of L. delicatula, as well as implications for long-term storage, that can aid in the development of a canine training aid for early detection and mitigation strategies. The spotted lanternfly (SLF) is an invasive species native to China. It was first discovered in the United States in Pennsylvania in 2014. It is known to cause great economic damage by destroying various crops, specifically grape vines, and therefore, several efforts have been made to control and mitigate its spread from the Northeast. Canine detection is a useful detection tool; however, it is crucial to understand the volatile organic compounds emitting by this pest to better direct canine training paradigms to prevent false alerts and to understand potential volatile markers of importance indicative of this species. The purpose of this study is to address the gap in research regarding the volatile organic compound (VOC) profile of SLF to better inform pest control mitigation strategies. Instrumental analysis was performed utilizing SPME-GC/MS on cold-killed SLF eggs, dried crickets, and tree bark. Differences in detected VOCs within each sample set depicted distinctive odor profiles for each matrix tested. Storage of these samples also depicted VOC accumulation variation as a function of time, thereby providing implications for long-term storage and sample handling for these types of training aids in canine applications. [ABSTRACT FROM AUTHOR]

Radiation resistance of diesel fuel with the addition of various percentages of toluene was studied. The experiments were carried out for a long time to study the postpolymerization processes. The kinetics of processes during irradiation of pure diesel fuel was studied at the temperature T = 20°C and dose rate P = 0.07 Gy/s in the range of absorbed doses D = 15–150 kGy, and a mixture of toluene with diesel fuel was irradiated within the absorbed dose range D = 24–90 kGy at a toluene concentration of 1, 3, and 5 vol %. Analysis by gas chromatography–mass spectrometric (GC/MS) was performed, and the density, viscosity, and iodine number of the diesel fuel before and after irradiation at various absorbed doses were determined. The kinetics of postpolymerization processes after the end of irradiation shows that the rate of the process and its share in the total polymerization depend on the irradiation time, initial mixture density, and dose. By adding additives (antirads), one can choose the composition of diesel fuel that will better withstand radiation exposure. It is necessary to find the optimal concentration of toluene in the composition of diesel fuel, at which the viscosity and density will not change with an increase in the absorbed dose. [ABSTRACT FROM AUTHOR]

The spotted lanternfly (SLF) is an invasive species native to China. It was first discovered in the United States in Pennsylvania in 2014. It is known to cause great economic damage by destroying various crops, specifically grape vines, and therefore, several efforts have been made to control and mitigate its spread from the Northeast. Canine detection is a useful detection tool; however, it is crucial to understand the volatile organic compounds emitting by this pest to better direct canine training paradigms to prevent false alerts and to understand potential volatile markers of importance indicative of this species. The purpose of this study is to address the gap in research regarding the volatile organic compound (VOC) profile of SLF to better inform pest control mitigation strategies. Instrumental analysis was performed utilizing SPME-GC/MS on cold-killed SLF eggs, dried crickets, and tree bark. Differences in detected VOCs within each sample set depicted distinctive odor profiles for each matrix tested. Storage of these samples also depicted VOC accumulation variation as a function of time, thereby providing implications for long-term storage and sample handling for these types of training aids in canine applications.

Hypericum perforatum L. aerial parts have been extracted with tetrahydrofuran solvent and their chemical composition has been investigated by Gas Chromatography-Mass Spectrometry (GC/MS) analysis. GC/MS chromatogram of the 4 tetrahydrofuran studied H. perforatum genotypes (HP) revealed that the main constituents for HP1 were: 9-Octadecenamide (Z)-(Oleic acid) (65.551%), Hexadecenamide (20.681%) and Dodecenamide (5.595%). Whereas, for HP2, they were 9-Octadecenamide (Z)- (Oleic acid) (63.117%), Hexadecenamide (19.107%) and Dodecenamide (5.585%). As for HP3, they were 9-Octadecenamide (Z)-(Oleic acid) (63.496%), Hexadecenamide (18.891%) and Dodecenamide (5.961%). Whereas, they were 9-Octadecenamide (Z)-(Oleic acid) (62.048%), Hexadecenamide (19.325%) and Dodecenamide (5.914%) for HP4. Thereby, isolation of these constituents and investigation of their biological activity is requested.

The effect of irradiation of AI-92 grade gasoline with benzene additive was studied. The kinetics of the processes was examined at temperature T = 20°C, dose rate P = 0.072 Gy/s in the absorbed dose range (D) of 27–78 kGy. The results of gas chromatography-mass spectrometry (GC/MS) analysis, IR spectroscopic studies, and determination of the density and viscosity of samples before and after irradiation at various absorbed doses are reported. An assessment of the physicochemical parameters of γ-irradiated gasoline with 1, 2, 4, 6% benzene additives shows that γ-radiation negatively affects the operating parameters (viscosity and density) of AI-92 gasoline. The optimal concentration of benzene in gasoline is 6%, at which viscosity and density diminish with increasing absorbed dose. The kinetics of post-polymerization processes within 8 months after the end of irradiation shows that the rate of the process and its proportion in the total polymerization depend on the irradiation time, the density of the initial mixture and the dose. [ABSTRACT FROM AUTHOR]

By the method of steam distillation, samples of essential oil were obtained from a plant cultivated in the East Kazakhstan region. The essential oil was obtained with a yield in terms of air-dry raw materials. By the gas liquid chromatography investigated a quantitative analysis of the essential oil components. Essential oil components of quantitative content calculated from the areas of gas chomatographic peaks. From plant of genus Zinnia elegans obtained main compounds of essentiol oil such as α-terpineol, β-myrcene, camphene and myrtenal. Terpineol has nice smell of lilac and is a sought-arter substance in the production of perfumes, fragrances and cosmetics. Pleasant smelling oily liquid. Myrcene has a large number of beneficial properties for the body, whether pure or in aromatherapy through the essential oils that contain it: Sedative and muscle relaxant, anti-inflammatory, interferon inhibition, gastric and duodenal ulcers, antalgic and antinociceptive, reduces sensitivity to pain by self-healing endogenous derivatives of morphine. Myrtenal – has an anti-inflammatory, resolving effect on acne, infiltrates. Increases the protective barrier of the epidermis. Antioxidant, rejuvenating. Camphene components are effective in the treatment of fungal, viral and bacterial infections that affect the respiratory system. [ABSTRACT FROM AUTHOR]

To study the quality and stability of tobacco casings, the sulfuric acid-methanol derivatization fingerprints of tobacco casings were established based on gas chromatography-mass spectrometry. A correlation coefficient method and a cosine including angle method were used to calculate the similarity between the abnormal samples and the standard samples. The abnormal samples included different batch samples, heated samples, mixed samples and diluted samples. Based on the test results from 13 batches, the similarity threshold was defined and used as the basis for assessing the quality stability of tobacco casings. The results of this method were compared with those of traditional physical and chemical indices and olfactory methods. The results showed that: 1) The fingerprints of tobacco casings from different batches had good stability and high similarity. 2) The similarity calculated by weighting the common peaks of each fingerprint based on the entropy method was superior to the unweighted method, and the correlation coefficient method was superior to the cosine including angle method. 3) Combined with the similarity calculation results and thresholds, the qualified tobacco casing samples and the abnormal samples, including heated samples, mixed samples and diluted samples, could be distinguished, especially at higher mixing and dilution ratios. 4) This method was more sensitive to evaluate the quality and stability of tobacco casings than the methods of physical and chemical indices and olfactory analysis, especially for samples with minor differences. This method can comprehensively and accurately monitor the quality of tobacco casings, and provide technical support and reference for evaluating the quality stability of tobacco casings. [ABSTRACT FROM AUTHOR]

Wild Achillea aleppica DC and Achillea arabica Kotschy flowering, aromatic and perennial herbs, grown in the Middle-Southern regions of Syria were assessed for their ethanolic and acetonic aerial parts extracts phytochemical analysis based on gas chromatography-mass spectrometry (GC/MS) analysis. Overall, GC/MS chromatogram revealed that the 9-Octadecenamide, (Z)- (41.656% and 61.097%) and Hexadecanamide (36.542% and 20.238%) were the most abundant compounds for ethanolic and acetonic A. aleppica aerial parts extracts, respectively. Whereas, 9-Octadecenamide, (Z)- (41.280% and 53.990%) and Hexadecanamide (30.828% and 14.445%) were the most abundant compounds for ethanolic and acetonic A. Arabica aerial parts extracts, respectively. This study could consider as the first report highlights A. aleppica and A. arabica extracts phytochemical analysis.

Hypericum perforatum L. aerial parts have been extracted with tetrahydrofuran solvent and their chemical composition has been investigated by Gas Chromatography-Mass Spectrometry (GC/MS) analysis. GC/MS chromatogram of the 4 tetrahydrofuran studied H. perforatum genotypes (HP) revealed that the main constituents for HP1 were: 9-Octadecenamide (Z)-(Oleic acid) (65.551%), Hexadecenamide (20.681%) and Dodecenamide (5.595%). Whereas, for HP2, they were 9-Octadecenamide (Z)- (Oleic acid) (63.117%), Hexadecenamide (19.107%) and Dodecenamide (5.585%). As for HP3, they were 9-Octadecenamide (Z)-(Oleic acid) (63.496%), Hexadecenamide (18.891%) and Dodecenamide (5.961%). Whereas, they were 9-Octadecenamide (Z)-(Oleic acid) (62.048%), Hexadecenamide (19.325%) and Dodecenamide (5.914%) for HP4. Thereby, isolation of these constituents and investigation of their biological activity is requested. [ABSTRACT FROM AUTHOR]

Major health issues, such as the rise in oxidative stress, incidences of Alzheimer's disease, and infections caused by antibiotic-resistant microbes, have prompted researchers to look for new therapeutics. Microbial extracts are still a good source of novel compounds for biotechnological use. The objective of the current work was to investigate marine fungal bioactive compounds with potential antibacterial, antioxidant, and acetylcholinesterase inhibitory effects. Penicillium chrysogenum strain MZ945518 was isolated from the Mediterranean Sea in Egypt. The fungus was halotolerant with a salt tolerance index of 1.3. The mycelial extract showed antifungal properties against Fusarium solani with an inhibitory percentage of 77.5 ± 0.3, followed by Rhizoctonia solani and Fusarium oxysporum with percentages of 52 ± 0.0 and 40 ± 0.5, respectively. The extract also showed antibacterial activity against both Gram-negative and Gram-positive bacterial strains using the agar diffusion technique. The fungal extract was significantly more effective with Proteus mirabilis ATCC 29906 and Micrococcus luteus ATCC 9341; inhibition zones recorded 20 and 12 mm, respectively, compared with the antibiotic gentamycin, which recorded 12 and 10 mm, respectively. The antioxidant activity of the fungus extract revealed that it successfully scavenged DPPH free radicals and recorded an IC50 of 542.5 µg/mL. Additionally, it was capable of reducing Fe3+ to Fe2+ and exhibiting chelating ability in the metal ion-chelating test. The fungal extract was identified as a crucial inhibitor of acetylcholinesterase with an inhibition percentage of 63% and an IC50 value of 60.87 µg/mL. Using gas chromatography–mass spectrometry (GC/MS), 20 metabolites were detected. The most prevalent ones were (Z)-18-octadec-9-enolide and 1,2-Benzenedicarboxylic acid, with ratios of 36.28 and 26.73%, respectively. An in silico study using molecular docking demonstrated interactions between the major metabolites and the target proteins, including: DNA Gyrase, glutathione S-transferase, and Acetylcholinesterase, confirming the extract's antimicrobial and antioxidant activity. Penicillium chrysogenum MZ945518, a halotolerant strain, has promising bioactive compounds with antibacterial, antioxidant, and acetylcholinesterase inhibitory activities [ABSTRACT FROM AUTHOR]

Background: The increasing problem of multi-drug resistant (MDR) pathogens is a worldwide concern, especially in the pharmaceutical industry. At the same time, medicinal plants have renewed interest because of their wide variety of bioactive phytochemicals, which could be used to develop new antimicrobial drugs. This renewed interest is partly due to the growing resistance to traditional drugs and their associated side effects., Methods: The objective of this study is to assess the antimicrobial properties of the total extract and various fractions of Adiantum capillus veneris against Methicillin-resistant Staphylococcus aureus (MRSA). The aerial parts of Adiantum capillus veneris were subjected to extraction using methanol, chloroform, and ether, and the resulting extracts were tested for their antimicrobial activity against MRSA. Additionally, essential oil was obtained from the aerial parts using a Clevenger apparatus and boiling water. Furthermore, Gas Chromatography-Mass Spectrometry (GC/MS) was utilized to analyze the phytochemicals isolated from the extracts of Adiantum capillus veneris., Results: The essential oil was obtained through distillation and then analyzed using GC/MS. The antimicrobial activity was evaluated using the agar diffusion method., Conclusion: GC/MS analysis revealed that the composition was primarily phytol (59.9%), constituting 99.3% of phyto-constituents. However, both the total extract and the individual fractions exhibited no inhibitory effects against MRSA strains., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Major health issues, such as the rise in oxidative stress, incidences of Alzheimer’s disease, and infections caused by antibiotic-resistant microbes, have prompted researchers to look for new therapeutics. Microbial extracts are still a good source of novel compounds for biotechnological use. The objective of the current work was to investigate marine fungal bioactive compounds with potential antibacterial, antioxidant, and acetylcholinesterase inhibitory effects. Penicillium chrysogenum strain MZ945518 was isolated from the Mediterranean Sea in Egypt. The fungus was halotolerant with a salt tolerance index of 1.3. The mycelial extract showed antifungal properties against Fusarium solani with an inhibitory percentage of 77.5 ± 0.3, followed by Rhizoctonia solani and Fusarium oxysporum with percentages of 52 ± 0.0 and 40 ± 0.5, respectively. The extract also showed antibacterial activity against both Gram-negative and Gram-positive bacterial strains using the agar diffusion technique. The fungal extract was significantly more effective with Proteus mirabilis ATCC 29906 and Micrococcus luteus ATCC 9341; inhibition zones recorded 20 and 12 mm, respectively, compared with the antibiotic gentamycin, which recorded 12 and 10 mm, respectively. The antioxidant activity of the fungus extract revealed that it successfully scavenged DPPH free radicals and recorded an IC50 of 542.5 µg/mL. Additionally, it was capable of reducing Fe3+ to Fe2+ and exhibiting chelating ability in the metal ion-chelating test. The fungal extract was identified as a crucial inhibitor of acetylcholinesterase with an inhibition percentage of 63% and an IC50 value of 60.87 µg/mL. Using gas chromatography–mass spectrometry (GC/MS), 20 metabolites were detected. The most prevalent ones were (Z)-18-octadec-9-enolide and 1,2-Benzenedicarboxylic acid, with ratios of 36.28 and 26.73%, respectively. An in silico study using molecular docking demonstrated interactions between the major metabolites and the target proteins, including: DNA Gyrase, glutathione S-transferase, and Acetylcholinesterase, confirming the extract’s antimicrobial and antioxidant activity. Penicillium chrysogenum MZ945518, a halotolerant strain, has promising bioactive compounds with antibacterial, antioxidant, and acetylcholinesterase inhibitory activities

Ethyl carbamate (EC), classified as a Group 2A carcinogen, is most abundant in the fermented foods, such as Cachaca, Shaoxing wine, and Chinese liquor (baijiu). Although biodegradation can reduce its concentration, a high ethanol concentration and acidic environment often limit its degradation. In the present study, a novel ethyl carbamate hydrolase (ECH) with high specificity to EC was isolated from Acinetobacter calcoaceticus, and its enzymatic properties and EC degradability were investigated. ECH was immobilized to resist extreme environmental conditions, and the flavor substance changes were explored by gas chromatography-mass spectrometry (GC/MS). The specific enzymatic activity of ECH was 68.31 U/mg. Notably, ECH exhibited excellent thermal stability and tolerance to sodium chloride and high ethanol concentration (remaining at 40% activity in 60% (v/v) ethanol, 1 h). The treatment of immobilized ECH for 12 h decreased the EC concentration in liquor by 71.6 μg/L. Furthermore, the immobilized ECH exerted less effect on its activity and on the flavor substances, which could be easily filtrated during industrial production. [ABSTRACT FROM AUTHOR]

To establish a method for the determination of phthalic acid esters in Peanut oil, Peanut oil samples were extracted with n-hexane saturated acetonitrile, purified by 25 mg PSA and 25 mg C18 and detected by GC-MS selected ion monitoring (SIM) mode detection, external standard method quantitative.The standard solution of 17 phthalates showed a good linearity in the concentration range of 0.02～3.0 mg/L,and the correlation coefficient (r) is above 0.999, the detection limit (LOD) was 0.01 mg/kg to 0.02 mg/kg,and the quantitative limit (LQD) was 0.03 mg/kg to 0.05 mg/kg. the recovery of standard addition was 92.47% to 108.72%, and the relative standard deviation was 1.10% to 5.94%.The method is simple, rapid,sensitive and accurate. and can be used for the determination of 17 phthalates in Peanut oils.

Background: Epilepsy is one of the most common neurological conditions and a significant cause of morbidity and mortality. Objectives: The present study aimed to evaluate the anticonvulsant activity of the petroleum ether extract of the root of Anacyclus pyrethrum on pentylenetetrazole (PTZ)-induced seizure model in Wistar rats. Methods: The composition of the petroleum ether extract of A. pyrethrum was first analyzed using gas chromatography-mass spectrometry (GC-MS). Subsequently, the anticonvulsant activities of these extracts (70 and 140 mg/kg, intraperitoneal injection) were evaluated on PTZ-induced seizures in rats. The protection rate against induced seizures, latency, and duration of seizures, as well as neurological symptoms, were assessed and compared to those protected by phenobarbital. Results: GC/MS analysis of the petroleum ether extract showed that the main components were octadecadienoic acid, hexadecanoic acid, diheptylcyclopropene, naphthalene, and methyl stearate. The extract (70 and 140 mg/kg) was found to provide significant protection against PTZ-induced seizures. Moreover, compared to the negative control, the extracts increased the latency of induced-convulsion and reduced the duration of epilepsy. Interestingly, the extracts showed a reduction in neurological symptoms and the severity of seizures compared to the negative control. All of these outcomes manifested in a dose-dependent manner. Conclusion: The petroleum ether extract of A. pyrethrum may produce anticonvulsant effects by reducing the duration of seizures and delaying the latency of seizures induced by PTZ.

Stored grains could lose substantially their nutritional quality, and consequently its value, between storage and consummation because of insect's infestation. One of the most frequent pests of wheat is the grain weevil (Sitophilus granarius L.). Cleverly hidden, the immature stages of this destructive pest are very difficult to identify. Protecting stored grains has become an agricultural challenge. In the present study, the essential oil (EO) distillated from Citrus limonum (L.) (Burm. F., 1768) and analyzed by gas chromatography-mass spectrometry (GC-MS) revealed the presence of 47 compounds with (Z)-citral (30.74%), dl-limonene (19.81%) and geranyl propionate (16.28%) as major components. In a second series of experiment, its fumigant (using filter paper), repellent (by semi circles joined discs) and residual (persistent insecticidal activity) activities were examined against Sitophilus granarius (L.) adults. The total nutrition (carbohydrates and lipids) depletion index (NDI) was also calculated. Residual toxicity and repellency of EO were demonstrated after fumigation against S. granarius with a dose-response relationship. The effectiveness of EO was exposure time dependent and its residual activity persisted up to 30 h following mortality. Moreover, data showed that treatment of S. granarius adults had adverse effects on the depletion of their energy reserves. C. limonum EO declined the lipid and carbohydrate contents in adults. Obtained data prove that botanical essential oils could be considered as potent biorational alternatives to synthetic insecticides for pest control of stored products in a sustainable manner. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the polycyclic aromatic hydrocarbons (PAHs) levels and health risk of yogurt and butter samples collected from Tehran using MSPE/GC‐MS (magnetic solid‐phase extraction/gas chromatography‐mass spectrometry). The results revealed that the limit of detection (LOD) and limit of quantification (LOQ) were ranged from 0.040 to 0.060 and 0.121 to 0.181 μg/kg, respectively; with recoveries ranged from 86.1% to 100.3%. The highest mean of total PAHs was higher in butter (6.87 ± 1.21 μg/kg) than in yogurt (3.82 ± 0.54 μg/kg). The level of benzo (a)pyrene in all samples was lower than of standard levels of the European Union (EU). The highest value of all PAHs in samples was recorded in the winter season and also in the expiration date. The percentile 95% of the total hazard quotient (THQ) due to the consumption of yogurt and butter recorded 1.33E‐02 and 3.69E‐04 in adults and 6.12E‐02 and 1.75E‐03 in children, respectively. The percentile of 95% incremental lifetime of cancer risk (ILCR) due to the ingestion of yogurt and butter recorded 1.17E‐06 and 2.02E‐08 for adults and 5.51E‐06 and 9.46E‐08 for children, respectively. The rank order of 7 PAHs in adult and children based on P95% Hazard Quotient (HQ) in all samples was benzo(a)anthracene (BaA) > pyrene (P) > fluorene (F) > fluoranthene (Fl) > acenaphthylene (Ace) > anthracene (A) > naphthalene (NA). According to the Monte Carlo Simulation (MCS) method, health‐risk assessment showed that children and adults are not at significant health risk. [ABSTRACT FROM AUTHOR]

Ethyl carbamate (EC), classified as a Group 2A carcinogen, is most abundant in the fermented foods, such as Cachaca, Shaoxing wine, and Chinese liquor (baijiu). Although biodegradation can reduce its concentration, a high ethanol concentration and acidic environment often limit its degradation. In the present study, a novel ethyl carbamate hydrolase (ECH) with high specificity to EC was isolated from Acinetobacter calcoaceticus, and its enzymatic properties and EC degradability were investigated. ECH was immobilized to resist extreme environmental conditions, and the flavor substance changes were explored by gas chromatography-mass spectrometry (GC/MS). The specific enzymatic activity of ECH was 68.31 U/mg. Notably, ECH exhibited excellent thermal stability and tolerance to sodium chloride and high ethanol concentration (remaining at 40% activity in 60% (v/v) ethanol, 1 h). The treatment of immobilized ECH for 12 h decreased the EC concentration in liquor by 71.6 μg/L. Furthermore, the immobilized ECH exerted less effect on its activity and on the flavor substances, which could be easily filtrated during industrial production.

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Effective and reliable uptake rates are crucial for applying passive samplers in monitoring gaseous volatile organic compounds (VOCs). However, there is currently a lack of data regarding the 24-h passive uptake rates of VOCs for workplace and environmental monitoring. This study aims to address this gap by utilizing a Tenax TA-based sampling tube to investigate the 24-h uptake rates of 25 kinds of VOCs in enclosed ship cabin environments. The results reveal that the uptake rate of VOCs ranges from 0.32 to 0.44 mL/min. A relationship between diffusive uptake rates and the boiling point of the compounds is proposed. The variation in uptake rate under different sampling durations was examined. The difference in uptake rate between 24 h and 8 h was smaller than that between 24 h and 6 days, with an average difference of 20%. In addition, the indoor uptake rate obtained in this study was compared with the outdoor uptake rates in the literature, and results showed that the outdoor uptake rate was generally higher than the indoor uptake rate, but the difference decreased when the sampling duration was longer. Field measurement was conducted by utilizing the measured uptake rates to characterize VOC pollution in both living and engine cabins in actual ships. This study contributes to facilitating the evaluation of environmental daily average concentrations in enclosed ship cabins, which will be helpful for assessing the effectiveness of air pollution control systems or epidemiological studies in ships. • 24h uptake rates of 25 kinds of VOCs under vessel environment were estimated. • A relationship between diffusive uptake rates and boiling point is proposed. • The difference in uptake rate under different sampling duration can reach 70%. • A field measurement campaign in a real vessel was conducted for VOC characterization. [ABSTRACT FROM AUTHOR]

A method of isotope dilution-gas chromatography-mass spectrometry (ID-GC/MS) was developed for analysis of 10 kinds of neutral trace aromatic components (benzaldehyde, 6-methyl-5-hepten-2-one, furfuryl acetate, methyl benzoate, isophorone, 2,4-dimethyl-acetophenone, 2-undecanone, geranyl acetone, β-ionone and benzyl benzoate) from cigarette smoke. 10 isotope markers (D5-benzaldehyde, 13C3-6-methyl-5-hepten-2-one, D3-furfuryl acetate, D5-methyl benzoate, D8-isophorone, D3-2,4-dimethyl acetophenone, 13C3-2-undecanone, 13C3-geranyl acetone, D4-β-ionone, D5-benzyl benzoate) corresponding to neutral aromatic components were added to Cambridge filter for collecting particles of cigarette smoke，and the aromatic components were extracted by simultaneous distillation and extraction method. The acidic and basic components in the extract were removed by washing with 5% hydrochloric acid and 5% sodium hydroxide aqueous solution (concentrations of volume percent), respectively, and the neutral components extract were obtained. The neutral aromatic components were analyzed by GC/MS under optimized conditions. The molecular ions and characteristic fragment ions with isotope atoms of isotope markers were selected as qualitative ions in qualitative identification in order to identify the corresponding target components. The qualitative identification of the target components in extract was assisted by the labeling effect of isotopes because of the addition of isotope markers, and the neutral aromatic components were identified reliably by comparing with characteristic fragments of isotope markers and retention time of reference standards in complex system. Many separation methods such as solid-phase microextraction (SPME) and preparative HPLC were omitted from the samples pretreatment process and the sample consumption was rather reduced. Two quantitative ions with higher signal-to-noise ratio and less interference were selected for each compound in quantitative analysis. The target neutral components in extract were analyzed by GC/MS using quantitative ions in SIM mode, and the results showed that the separation of target compounds from interfering components was completely and the accurate quantitative analysis could be carried out. The contents of 10 neutral components were simultaneous determined by internal standard curve method using corresponding isotopes as internal standard. The analysis results showed that the correlation coefficients are greater than 0.999 0, the limits of detection (LODs) are 0.34-4.59 μg/kg, and the limits of quantity (LOQs) are 1.14-15.30 μg/kg. The average recovery is in the range of 83.3%-106.6%, and the relative standard deviations (RSDs) are in the range of 0.15%-8.69%. This method is sensitive and accurate，which is suitable for quantitative analysis of neutral aromatic components in cigarette smoke. [ABSTRACT FROM AUTHOR]

A method for simultaneous determination of 16 synthetic musks (including 5 nitro musks, 6 polycyclic musks and 5 macrocyclic musks) and 2 UV filters (BP-3 and UV-P) in water samples was developed by stir bar sorption extraction (SBSE) with liquid desorption (LD), coupled with gas chromatography-mass spectrometry (GC/MS). In order to get good extraction efficiencies of the target compounds, the important factors affecting the stir bar sorption extraction procedure were discussed, such as extraction time, temperature, stirring speed, volume of sample, pH value, ionic strength, content of organic modifier, different extraction solvents for desorption and the time of liquid desorption by ultrasound extraction. Finally, 50 mL water sample with certain amount of surrogate was stirred extraction for 4 h at 40 °C with magnetic stir bar of PDMS, the stirring speed was 950 r/min. Then the stir bar was resolved twice with acetonitrile-acetone solvent. The extract was concentrated to 0.5 mL and added the internal standard for injection. The chromatographic separation was carried on a DB-5MS Ultra Inert column (30 m×0.25 mm×0.25 μm) and detected by mass spectrometry at selected ion monitoring (SIM) mode. The results show that 16 synthetic musks and 2 UV filters have good linearity, the linear range of this method is 2-120 μg/L, while the correlation coefficients (R2) are more than 0.996. The recoveries of three spiked level range from 68.5% to 126%, the relative standard deviations (RSDs) of this method are 2.3%-14.9%, and the limits of detection (LOD) range from 3 μg/L to 0.038 μg/L. Moreover, the method was applied to detect surface water samples in Beijing. The results show that the detection rate of HHCB is the highest, and the concentration is between 0.003 μg/L and 0.337 μg/L. In conclusion, this method is suitable for the rapid analysis of 16 synthetic musks and 2 UV filters in water samples with easy operation, less organic solvent consumption, and can be applied to the accurate analysis of synthetic musks and UV filters in actual surface water samples. [ABSTRACT FROM AUTHOR]

A non-targeted analysis workflow was applied to analyze exhaled breath samples collected from firefighters pre- and post-structural fire suppression. Breath samples from firefighters functioning in attack and search positions were examined for target and non-target compounds in automated thermal desorption-GC/MS (ATD-GC/MS) selected ion monitoring (SIM)/scan mode and reviewed for prominent chemicals. Targeted chemicals included products of combustion such as benzene, toluene, xylenes, and polycyclic aromatic hydrocarbons (PAH) that serve as a standard assessment of exposure. Sixty unique chemical features representative of exogenous chemicals and endogenous compounds, including single-ring aromatics, polynuclear aromatic hydrocarbons, volatile sulfur-containing compounds, aldehydes, alkanes, and alkenes were identified using the non-targeted analysis workflow. Fifty-seven out of 60 non-targeted features changed by at least 50% from pre- to post-fire suppression activity in at least one subject, and 7 non-targeted features were found to exhibit significantly increased or decreased concentrations for all subjects as a group. This study is important for (1) alerting the firefighter community to potential new exposures, (2) expanding the current targeted list of toxicants, and (3) finding biomarkers of response to firefighting activity as reflected by changes in endogenous compounds. Data demonstrate that there are non-targeted compounds in firefighters' breath that are indicative of environmental exposure despite the use of protective gear, and this information may be further utilized to improve the effectiveness of personal protective equipment. [ABSTRACT FROM AUTHOR]

To assess the presence of prohibited anabolic substances used to promote growth in livestock, calf urine is the most relevant matrix. However, the sample preparation methods (required to remove unwanted matrix components and fractionate isobaric species that may be unresolved by gas chromatography- mass spectrometry GC/MS) are long and complex. In this context, semi-preparative supercritical fluid chromatography (SFC) was considered to possibly simplify the sample preparation in reducing the number of procedures. Fifteen stationary phases were screened with SFC combined with UV and evaporative light-scattering detection (ELSD), among which two columns (Cosmosil π-NAP and Princeton DIOL) were retained for their ability to isolate steroid hormones from other matrix components and, for the second column, for the additional possibility to fractionate steroid hormones into different families (estrogens, mono-hydroxylated and di-hydroxylated androgens). The fractions were further analysed with GC/MS showing the benefit of class fractionation. The final method allows for significant time, solvent and money savings compared to the previously widely used method (solid-phase extraction combined with semi-preparative high-performance liquid chromatography). [ABSTRACT FROM AUTHOR]

Sugars and sugar alcohols are the most important primary metabolites in plant tissues， which provide energy， free radical scavenging and regulation of plant cell osmotic pressure and other physiological functions. Their equilibrium is directly associated with the physiological condition of plant tissues. For example，sorbitol and mannitol are two important derivatives of monosaccharides，which are mainly involved regulation of osmotic stress and important for plant growth and stress signaling. These sugar and sugar alcohols are usually detected by titration，spectrophotometric method， enzymatic analysis and chromatographic analysis. However， these chemicals in plant tissue are kept at low concentration. To enhance the sensitivity for plant endogenous sugars and sugar alcohols detection, gas chromatography-mass spectrometry (GC/MS) combined with selected ion monitoring (SIM) was established. 7 kinds of sugar and sugar alcohols, including of fructose (Flu) , glucose (Glu)，galactose (Gal) , inositol (Ino) , mannitol (Man)，sucrose (Sue) and sorbitol (Sor) were detected in plant tissues at a low concentration. The result showed that fructose concentration was 5. 5 mg/L， the others were below 0.11 mg/L， and the relative standard deviation (RSD) was between 2. 3%and 4. 9 %. As an application，these chemicals in Lycium chinensis tissue were detected. The contents of sucrose and glucose in root were more than 2 times these of the leaves，while the galactose and inositol had no difference in the two tissues. [ABSTRACT FROM AUTHOR]

The composite algorithm proposed by Stein and Scott was improved， whose weight factors were optimized by the weighting factors proposed by Kim et al， and whose coefficients of weighted dot-product similarity measure and peak ratio algorithm were redistributed. Using the improved composite algorithm，30 932 mass spectra in the query library were retrieved in the Mass Spectral Library 2011 (NIST 11) main library (212 961mass spectra) used as reference spectral library. In addition，8 kinds of different compounds were analysed by gas chromatography-mass spectrometry (GC/MS)， and the corresponding mass spectra were also retrieved in the NIST 11. In order to evaluate the performance of the algorithm， two different sets of experiments were carried out, and the accuracy and similarity of the query spectra or the experimental samples were analysed by using two combinatorial algorithms respectively. The results showed that compared with the previous composite algorithm, the accuracy of the query spectra matching in the reference spectral library was increased by 1. 15% , and the similarity of the 94. 45% of the mass spectra in the query library were improved. The spectrum of the sample through the GC/MS had higher hit rates in the reference spectral library, and the spectrum similarity increased 3. 56 % in average. Since the improved composite algorithm can improve the accuracy and similarity of the spectrum to be measured in the reference spectral library, it can also be used to improve other algorithm based on Stein and Scott's composite algorithm. [ABSTRACT FROM AUTHOR]

Traditionally, gas chromatography–mass spectrometry (GC/MS) analysis has used a targeted approach called selected ion monitoring (SIM) to quantify specific compounds that may have adverse health effects. Due to method limitations and the constraints of preparing duplicate samples, the information that could be obtained from separately collecting the full scan chromatogram of the sample has often been sacrificed. However, the hybrid technique called synchronous SIM/scan mode alternates between the two acquisition modes, maintaining the accuracy and sensitivity of SIM for targeted analysis while also providing the full scan chromatogram for discovery of non-target compounds. This technology was assessed using calibration data and real-world breath samples from a joint EPA/NIOSH collaboration that investigated the safety of firefighters’ protective gear during controlled structure burns. Collecting field samples is costly and must be performed strategically to ensure that time points and replicates are accurate and representative of the intended population. This is difficult to accomplish with firefighters who are working under volatile conditions. The synchronous SIM/scan method decreases the number of field samples that need to be collected by half and reduces error in trying to recreate time points since a breath sample from a single sorbent tube can be used to collect both the SIM and scan data simultaneously. As a practical demonstration of the method, we investigate thirty-six firefighter breath samples, document organic compounds of interest, and identify additional non-target compounds. [ABSTRACT FROM AUTHOR]

Halogenated phosphate ester flame retardants in polymer material of electrical and electronic products were extracted by ultrasound with acetone solvent for 1.5 h, then the extract was evaporated to almost dryness and dissolved with 1.0 mL n-hexane, and detected by instrument. In order to improve method selectivity and reduce sample preparation procedure, negative chemical ionization (NCI) model was selected. Taget analytes were determined qualitatively and quantitatively at 210 ℃ of ion source temperature with 2.5 mL/min of methane gas flow. The linear range of tris-(2-chloroethyl) phosphate (TCEP) and tris-(1-chloro-2-propyl) phosphate (TCPP) are 0.10-10 mg/L with R2≥0.999, while tris-(1,3-dichloro-2-propanol) phosphate (TDCP) and tris-(2,3-dibromo-1-propanol) phosphate (TDBP) are 0.010-10 mg/L with R2≥0.999. The limit of detection (S/N=3) is 0.010 mg/kg for TCEP and TCPP, and 0.001 mg/kg for TDCP and TDBP. The limit of quantitative (S/N=10) is 0.10 mg/kg for TCEP and TCPP, and 0.010 mg/kg for TDCP and TDBP. The feasibility of this method was demonstrated by determination of halogenated phosphate ester fire retardants in electrical and electronic products with spiked recoveries, which is in the range of 85.6%-108.9%, the relative standard deviation (RSD) is less than 8.5%. 30 actual samples were analyzed, including acrylonitrile-butadiene-styrene (ABS), polyvinyl chloride (PVC), printed circuit board which was mainly made from epoxy resin and polypropylene (PP). Only two samples are detected with TCPP concentration of 367.5 mg/kg and 695.2 mg/kg. Therefore, there is a certain risk of halogenated phosphate ester flame retardants for polymer material of electrical and electronic products. [ABSTRACT FROM AUTHOR]

Edible oils are used worldwide, but there is a shortage in developing countries, especially those that do not produce olive, soy, and rapeseed oils. Trying to explore the Iranian biodiversity, Pyrus glabra seeds were studied for the extraction and characterization of the oil. Seven fatty acids were presented in P. glabra seed oil, with oleic acid (ω-9) accounting for 52.1% of the total oil, followed by linoleic acid, ω-6 (33.75%) and palmitic acid (6.69%). P. glabra seed oil had a refractive index of 1.47 at room temperature and contained 5.5 mg KOH/g, 69.4 g I 2 /100 g, and 134.3 mg KOH/g in terms of acid value, iodine value, and saponification value. FTIR of P. glabra seed oil showed peaks related to several functional groups, including hydrogen bonds, double bonds, and C O, C–O, and C–C bonds. The DSC analysis of the seed oil revealed the detection of three exothermal peaks during cooling, which corresponded to different crystallization temperatures of the fatty acid components in the oil. The most significant endothermal and exothermal peaks were observed at low temperatures during the melting process. It is potential for P. glabra seed oil to be fully developed and utilized with the help of this research. [Display omitted] • P. glabra seed oil was characterized by GC-MS, DSC, and FTIR analysis. • P. glabra seed oil was a rich omega-9 fatty acid (oleic acid) source. • P. glabra seed oil exhibited polymer-like behavior upon cold crystallization. • FTIR showed chemical functional groups of P. glabra seed oil. [ABSTRACT FROM AUTHOR]

The lavender has been widely used in food, aromatherapy, fragrant and pharmaceutical industries due to its unique chemical composition which confers both aromatic and biological activities. A method was established to fast identify the chemical constituents by phase micro-extraction-gas chromatography-mass spectrometry (SPME-GC/MS) and provided the basis for distinction of the different species by analyzing the remarkably different chemical components in the lavender. Based on the peak areas of cis-β-ocimene, linalool, linalyl acetate, terpinen-4-ol, caryophyllene and caryophyllene oxide, three parameters (temperature, time of extraction and desorption time) of headspace solid-phase micro-extraction (HS-SPME) were optimized, resulting in the best extraction condition including extraction temperature of 55 ℃, extraction time of 30 min and desorption time of 30 s. Twenty-six volatile oil samples collected in Xinjiang which belong to three different lavender species were analyzed by GC/MS．Principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) were used to analyze the aroma profiles of the lavender. The results show that the chemical compositions in lavender from different species are clearly distinguished. Kinds of 9 chemical compositions, such as linalool, caryophyllene, cis-β-farnesene, linalyl acetate, lavandulyl acetate, germacrene D, cis-β-ocimene, terpinen-4-ol and caryophyllene oxide, which are indentified as discrimination markers. This study can provide the basis for rapidly qualitative analysis of constituents and quantity control of the lavender. [ABSTRACT FROM AUTHOR]

Rigid polyurethane foam (RPUF) exhibits wide applications in building engineering and thermal insulation, as well as furniture components due to its excellent mechanical and insulation properties. However, RPUF is highly flammable, combustion of which can cause serious economic loss and release smoke that is extremely harmful to the environment. Therefore, it’s of great importance to improve the flame retardancy of RPUF. The use of intumescent flame retardants is one of the most economical and efficient ways to protect polymeric materials against fire. In this work, ammonium polyphosphate (APP) and expandable graphite (EG) were added to RPUF as flame retardants. Pyrolysis processes of pure RPUF and these two flame retarded RPUFs were investigated using thermogravimetry (TG), gas chromatography-mass spectrometry (GC/MS) and on-line photoionization mass spectrometry (PIMS). TG analysis shows that all the samples decompose in two major steps and more high-temperature residues are formed with the addition of APP and EG. On the basis of GC/MS analysis, the secondary pyrolysis products of PU are remarkably changed by APP. Large quantities of nitrogen-containing PAHs were found in the pyrolyzates of RPUF/APP, which could subsequently form the char layer to increase the flame retardancy of PU. However, the flame retardancy of EG mainly depends on its physical expansion character. Moreover, extremely similar pyrolyzates are exhibited for pure RPUF and RPUF/EG, which reveals that EG is typically a physical expanding retardant. By virtue of the on-line detection and soft ionization characteristics, PIMS was used to further confirm the above experimental results. Two stages of the pyrolysis process could be assigned respectively to the primary decomposition of RPUF and to secondary reactions of primary products. However, PIMS with rare gas discharge lamp as ionization source has some inevitable drawbacks, such as fixed wavelength, low photon flux and large emittance. Recently, synchrotron vacuum ultraviolet (SVUV) light has proved to be a great choice of ionization source of PIMS. Relative works could be performed with SVUV-PIMS in the future. [ABSTRACT FROM AUTHOR]

To explore the feasibility of using chlorine isotope abundance ratio to investigate the degradation of organochlorine pollutants in air, gas chromatography-high resolution time-of-flight mass spectrometry (GC-HR-TOF MS) method was carried out for calculation of chlorine isotope abundance ratio (37Cl/35Cl) based on measurements of atmospheric hexachlorobenzene (HCB) in both industrial (Tanggu and Hangu) and rural (Yuqiao) sites in Tianjin. Air samples were collected using passive air sampler with XAD-2 resin as absorbent. Interference free HCB peaks were obtained as indicated by accurate masses and good spectral match. The chlorine isotope abundance ratio (37Cl/35Cl) of HCB was derived from its isotopic peak profile. Since fragmentation may complicate the situation, molecular ions were preferred. Most of the mass peaks ought to be taken into calculation，however, inclusion of small fragment ions may deteriorate the precisions of the chlorine isotopic ratios finally calculated. The experimental data indicates that the precision (RSD) of 37Cl/35Cl ratio ranges 2‰-5‰. The chlorine isotope abundance ratio (37Cl/35Cl) of HCB in industrial Tanggu and Hangu sites was 0.319 3±0.001 6 and 0.320 7±0.000 8, respectively,whereas that in rural Yuqiao was 0.323 9±0.000 8; the former was statistically lower than the later, as expected theoretically, which was attributable to the degradation of HCB during the atmospheric transport from source region to receptor sites. The chlorine isotope abundance ratios (37Cl/35Cl) of HCB obtained in this work are comparable and in good agreement with those in previous studies. It is encouraging and promising to use GC-HR-TOF MS to determine the chlorine isotope abundance ratio (37Cl/35Cl) of organochlorine pollutants such as HCB, and, in turn, to investigate related environmental processes such as degradation. Further studies could investigate the effects of different ionization methods and conditions, concentration levels of target compounds on the isotopic abundance ratios and its precisions obtained. It could be extended to more chlorine-containing pollutants of interest in other environmental matrices. [ABSTRACT FROM AUTHOR]

As a dacryagogue, 2-chlorobenzalmalononitrile (CS) is widely used in the equipment for anti-terrorism and anti-riot in many countries. Explosion and combustion are used to disperse CS to aerosol in the air, and then make it decomposed. In order to improve the utilization efficiency of CS, there is necessity to study its performance of thermal stability and thermal decomposition. In this paper, thermal weight loss and thermal effects of CS were measured by thermal analysis (TGA/DSC) technique at different heating rates. Moreover, the properties of evolved gases were analyzed in combination with fourier transform infrared spectroscopy (FTIR). The performances of thermal decomposition of CS were investigated at the temperatures ranging from 350 ℃ to 650 ℃ in thepyrolysis apparatus by gas chromatography-mass spectrometry (GC/MS). It has been found that CS begins to melt at 96 ℃, boil near 310 ℃ and initially decompose between 450 ℃ and 550 ℃. The types of product are increased with the rise of temperature. In detail, CS is decomposed to four products at 550 ℃ and the amount of products is up to ten products at 650 ℃ when the thermal decomposition deepens. According to the experimental results, the pyrotechnic mixture for tear gas munitions should not burst above 450 ℃. [ABSTRACT FROM AUTHOR]

A method for analyzing by product from cyclohexane oxidation by multiple mass spectrometry technologies was established. The by product was distilled to light fraction (distillation range <300 ℃) and heavy fraction (distillation range >300 ℃) by vacuum distillation. The qualitative and quasi-quantitative analysis for the light fraction of the by product were carried out by comprehensive two-dimensional gas chromatography-time of fight mass spectrometry (GC×GC-TOF MS). 54 kinds of oxygen compounds, which composed of ketones, ethers, alcohols, esters, aldehydes, phenols and hydrocarbons are identified. The carbon number distribution of the light fraction is 5-14. The compounds, with the carbon number of 12, account for more than 70% of the light fraction. As the carbon number of 2-cyclohexylidene-cyclohexanone, 2-(1-cyclohexenyl) cyclohexanone and oxydicyclohexane, which are the major compounds of the light fraction, were all 12. The compounds with the carbon number of 6 have the second highest content.The composition of the heavy fraction is more complex than the light fraction. It was characterized by Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS). The main components of the heavy fraction are O2-O5 compounds. The carbon number distribution of these oxygen compounds range widely, which are from 10 to 40. The compounds with the carbon number of 18 and 24 have higher content. The fact that compounds with multiples of 6 carbon atoms have higher content both in light and heavy fraction, illustrates that the structure of cyclohexane is reserved during the oxidation procedure. As for the compounds in the heavy fraction, their carbon numbers increase with the rising of oxygen numbers, while the distribution of double bond equivalents (DBE) remains the same. The structures of hexatomic ring, C = C, C = O and C—O of alcohols or ethers were predicted in the heavy fraction, which was verified by Fourier transform infrared spectroscopy (FTIR). The detailed composition information is helpful for the reproduction and reprocessing of the by product from cyclohexane oxidation. It can provide a new method for analyzing and researching of the complex system containing oxygen compounds. [ABSTRACT FROM AUTHOR]

Modern rectified spirit is distilled ethanol (EtOH) containing only a tiny amount of methanol (MeOH), as opposed to former industrial alcohol, and is frequently used by perpetrators to adulterate or counterfeit Scotch whiskies in Taiwan. As a result, MeOH level presents an obvious discrepancy between adulterated whiskies and authentic Scotch whiskies. In this study, 54 authentic single malt Scotch whisky samples and 30 authentic blended Scotch whisky samples were comparatively analyzed. Instead of various analog internal standards often spiked for GC/MS quantitative analyses, the isotope-labeled internal standard 2H 3 -MeOH was employed for optimizing the Scotch whisky analysis to achieve a limit of quantitation (LOQ) of 5 ppm for MeOH. The resulting data were further analyzed by a distribution fitting method and showed that the distribution of MeOH levels corresponded to a lognormal distribution for both authentic single malt Scotch whiskies and authentic blended Scotch whiskies. Based on the statistical characteristics of the lognormal distribution, 99.7% of the MeOH concentrations would lie between 13.4 and 44.2 ppm for authentic single malt Scotch whiskies and between 7.87 and 74.9 ppm for authentic blended Scotch whiskies, suggesting that the MeOH level might serve as a marker for the authentication of the seized Scotch whiskies in Taiwan. • 2H3-MeOH was used as internal standard (IS) to achieve 5ppm of the limit of quantitation (LOQ). • The distribution of MeOH contents corresponded to lognormal distribution in Scotch Whiskies. • MeOH concentration level could be considered as an exclusionary criterion for the authentication purpose. [ABSTRACT FROM AUTHOR]

Background: Acute coronary syndrome (ACS) is one of the leading causes of death and is often accompanied by hypertension., Methods: We investigated whether hypertension affects the metabolism of patients with ACS. Serum samples were provided from healthy controls (HCs; n=26), patients with ACS (n=20), or those patients with ACS complicated with hypertension (HTN, n=21), and all were subjected to non-targeted metabolomics analyses based on gas chromatography-mass spectrometry (GC/MS). Differential metabolites were screened using principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and orthogonal partial least squares discriminant analysis (OPLS-DA). Kyoto Encyclopedia of Genes and Genomes (KEGG) provided metabolic pathways related to these metabolites., Results: Compared to those in the HC group, 12 metabolites were significantly upregulated and 6 significantly downregulated in the ACS group; among these, L-cystine and isocitric acid showed the most obvious differences, respectively. Compared to those in the ACS group, 3 metabolites were significantly upregulated and 2 metabolites were significantly downregulated in the ACS-HTN group, among which oleic acid and chenodeoxycholic acid showed the most marked difference, respectively. The five most prominent metabolic pathways involved in differential metabolites between the ACS and HC groups were arginine biosynthesis; oxidative phosphorylation; alanine, aspartate and glutamate metabolism; citrate cycle; and glucagon signaling pathway. The metabolic pathways between the ACS and ACS-HTN groups were steroid biosynthesis, fatty acid biosynthesis, arginine biosynthesis, primary bile acid biosynthesis, and tyrosine metabolism., Conclusions: A comprehensive study of the changes in circulatory metabolomics and the influence of HTN was conducted in patients with ACS. A serum metabolomics test can be used to identify differentially metabolized molecules and allow the classification of patients with ACS or those complicated with HTN., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://atm.amegroups.com/article/view/10.21037/atm-22-6409/coif). The authors have no conflicts of interest to declare., (2023 Annals of Translational Medicine. All rights reserved.)

An elevated uric acid (UA) in urine or serum can affect renal function and blood pressure, which is an indicator of gout, cardiovascular and renal diseases, hypertension, etc. In this work, a new type of mixed matrix membrane (MMM), based on graphitic carbon nitrides (g-CNs) and hollow fiber (HF), was prepared and combined with solid phase microextraction (SPME) mode to determine UA in urine and serum followed by gas chromatography-mass spectrometry (GC/MS). The porous g-CNs were dispersed in ammonia, and then the exfoliated g-CNs nanosheets were held in the pores of HF by capillary forces and sonification. The prepared g-CNs modified HF (g-CNs-HF) was immersed in biofluid directly to extract UA with SPME mode and the solvent-free mode is convenient for further derivatization and analysis. To achieve the highest extraction efficiency (EF), main extraction and derivatization parameters, such as g-CNs-HF immobilizing time, sonification power and time of extraction, derivatization and desorption time, were optimized. Under the optimum extraction conditions, a favorable linearity of UA was obtained in the range 0.1–200 μg mL −1 with correlation coefficients higher than 0.9990, and the average recoveries at three spiked levels of UA in urine and serum ranged from 80.7% to 121.6%, from 84.7% to 101.1%, respectively. The obtained results demonstrated the developed g-CNs-HF-SPME is a simple, rapid, cost-effective, solvent-free method for the analysis of UA in biofluid. [ABSTRACT FROM AUTHOR]

Three adult cave-dwelling ground beetle species were induced to discharge secretions of their pygidial glands into vials. Dichloromethane extraction was used to obtain the secretions. In total, 42 compounds were identified by GC/MS analysis. Pheggomisetes ninae contained 32 glandular compounds, Laemostenus ( Pristonychus) punctatus 13, whereas Duvalius ( Paraduvalius) milutini had nine compounds. Caproic, oleic, palmitic, and stearic acids were present in the samples of all analyzed species. Undecane was predominant in the extract of L. punctatus. Palmitic acid was the major component in the secretion of D. milutini. Finally, the most abundant compounds in P. ninae secretion were heptacosene and nonacosadienes. Herein, we present the first data on the identification of pygidial gland secretion components in both troglophilous and troglobite cave-dwelling ground beetles. Some compounds are reported for the first time in the secretions of ground beetles and other higher or lower taxa. The adaptation to underground life has not led to a reduction or changes in the chemical defense mechanism in the analyzed troglophilous and troglobitic Platyninae and Trechinae taxa. [ABSTRACT FROM AUTHOR]

We have discovered that leaves from the halotolerant plant saltcedar ( Tamarix canariensis [Willd.]) are a source of resorcinols and guaiacols. Specifically, the waxes of the saltcedar leaves contained high amounts of 5 -n -alkylresorcinols (ARs; 17 g/kg dry weight), 5 -n -alkyl -m -guaiacols (AGs; 14 g/kg dw) and secondary alcohols (44 g/kg dw). Herein we provide the report of 5- n -alkylresorcinols with long side-alkyl chains as natural compounds in Tamaricaceae. These compounds are homologous to ones previously reported almost exclusively in cereals. The ARs span the formulas n -C 14 to n -C 27 , the most abundant of which is n -C 21 . Although the odd-C-numbered compounds dominate, there are non-negligible amounts of the even-numbered homologs. We also provide, the first-ever report of 11 homologs of 5 -n -alkyl -m -guaiacols (AGs) as natural compounds from the sample plant, which we characterized as the corresponding trimethylsilyl (TMS)-ether derivatives. The AGs contain a hydroxyl group at carbon 1 of the phenolic nucleus, a methoxy group at position 3, and a (predominantly odd-C-numbered) linear alkyl chain linked to the benzene ring at position 5. They span the formulas n -C 13 to n -C 27 , the most abundant of which is n -C 21 . Finally, we also isolated from saltcedar a series of eight asymmetric secondary alcohols, whose formulas range from n -C 25 to n -C 35 and whose major homolog is n -hentriacontan-12-ol. [ABSTRACT FROM AUTHOR]

Highlights: [•] Balm Mint is an aromatic and medicinal plant. [•] Lemon balm is beneficial for a wide variety of human disorders. [•] Lemon balm has therapeutic properties. [•] EO producers and consumers could employ this phenomenon benefits. [ABSTRACT FROM AUTHOR]

Abstract: We carried out time-resolved experiments using a proton-transfer-reaction mass spectrometer and a chassis dynamometer to characterize nitromethane emission from automotive exhaust. We performed experiments under both cold-start and hot-start conditions, and determined the dependence of nitromethane emission on vehicle velocity and acceleration/deceleration as well as the effect of various types of exhaust-gas treatment system. We found that nitromethane emission was much lower from a gasoline car than from diesel trucks, probably due to the reduction function of the three-way catalyst of the gasoline car. Diesel trucks without a NO x reduction catalyst using hydrocarbons produced high emissions of nitromethane, with emission factors generally increasing with increasing acceleration at low vehicle velocities. [ABSTRACT FROM AUTHOR]

Highlights: [•] We applied a new method to determinate of PAHs in Iranian smoked fish. [•] The effective variables of this method were optimised using Box–Behnken design. [•] A comparison of 16 PAHs was carried out between 4 species of Iranian smoked fish. [•] The effects of fat and surface area were investigated on PAHs concentration. [Copyright &y& Elsevier]

Highlights: [•] A sensitive analytical method for 2-chlorohippuric acid in urine is reported. [•] 2-Chlorohippuric acid is a human urinary metabolite of the riot control agent CS. [•] 2-Chlorohippuric acid can be detected in human urine 20h after mild exposures to CS. [•] 2-Chlorobenzyl-N-acetylcysteine, a CS metabolite in the rat, was not detected. [Copyright &y& Elsevier]

Objective: Acute intermittent porphyria (AIP) is an autosomal dominant disease that results from a deficiency of hydroxymethylbilane synthase, the third enzyme of the heme biosynthetic pathway. AIP carriers may present acute neurovisceral attacks with hepatic overproduction of heme-precursors. In some patients, remission of the acute symptoms leads to long-term hepatic metabolic abnormalities. In this study, gas chromatography–mass spectrometry (GC/MS) was used to investigate urinary steroid metabolome of AIP patients. Design and methods: Steroid profiling in urine was performed in a group of AIP patients with biochemically active disease (n=22) and healthy controls (n=20). Five asymptomatic AIP family carriers were also studied. Commonly used ratios for the evaluation of disturbances in the steroid metabolism were calculated. Results: We found that etiocholanolone/androsterone and tetrahydrocortisol/5α-tetrahydrocortisol (THF/5α-THF) metabolic ratios were significantly increased in the urine of AIP patients compared to controls (2.3±0.3 vs 0.8±0.1; p<0.001 and 2.9±0.7 vs 0.9±0.1; p<0.01). The (THF+5α-THF)/tetrahydrocortisone ratio was reduced among the AIP patients (p<0.01). Quantification of the steroid absolute concentrations showed that these variations were due to a decrease of the 5α metabolites. Other ratios, like cortisol/cortisone and 6β-hydroxycortisol/cortisol in the free steroid fraction did not show differences between patients and controls. All ratios were normal among the family carriers. Conclusion: A significant number of AIP patients present a basal decrease of steroid 5α-reductase activity in the liver. The deficiency may be related to malnutrition and hepatic energy misbalance associated with active AIP. Urinary steroid profiling by GC/MS may be a valuable tool to assess hepatic metabolome in AIP. [ABSTRACT FROM AUTHOR]

Abstract: Volatile composition of monovarietal young red wines made from Negroamaro cultivar, an autochthonous grape variety of Vitis vinifera grown exclusively in Salento area (southeast of Italy in Apulia region), was investigated. Volatile compounds were extracted following a solid phase extraction (SPE) method, and then analysed by gas chromatography–mass spectrometry (GC/MS). Results showed a complex aroma profile rich in alcohols, esters and fatty acids, with a minor contribute from aldehydes, lactones, volatile phenols and sulphur compounds. For the first time, aromatic patterns that characterise wines produced from Negroamaro autochthonous grape variety were established, starting a fundamental register of typicity and geographical identity of Apulians wines. Statistical data analysis techniques (Principal component analysis (PCA) and ANOVA) showed the structure of the experimental data and the significant differences for each compound in the different wines. [Copyright &y& Elsevier]