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Fragrance allergens (FAs) have been widely used in wet wipes, diapers, sanitary napkins, and other paper personal care products. There are more than 1000 fragrance allergens that may be present in these products. However, their negative effects on human health and environment cannot be ignored. This work presented a headspace (HS) solid-phase microextraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS) for the determination of fragrance allergens in paper personal care products. The factors affecting the extraction efficiency were optimized by response surface methodology (RSM). Under optimal conditions, the method provided good linearity (R-0.995) from 2.5x10-4 to 1.28x10-1mg with low limits of detection (LODs) between 1.9x10-2 and 6.0 mg/kg. Twenty paper personal care products were analyzed and 12 fragrance allergens were detected. The detection rate of benzyl alcohol was the highest (80%) with contents from 0.009 to 5.73mg/kg, followed by linalool (over 75%) with a content of 12.30mg/kg in makeup removing wipes. Additionally, a comparison for the determination of fragrance allergens by solid-liquid extraction-dispersive liquid-liquid microextraction (SLE-DLLME) and HS-SPME was reported. HS-SPME has been demonstrated to be a sensitive screening method for fragrance allergens in paper personal care products. [ABSTRACT FROM AUTHOR]

The occurrence of 2- and 3-monochloropropanediol (MCPDs) in selected paper products sold on the Canadian market and the transfer of 3-MCPD from those products to beverages was probed. Products included coffee filters, tea bags, disposable paper hot beverage cups and milk packaged in paperboard containers. The occurrence MCPDs in coffee and tea filters on the German market was investigated as well. Furthermore, the presence of MCPDs in paper towels on the German market was also investigated. Analytes were determined by stable isotope dilution analysis GC-MS in SIM mode. 3-MCPD was detected in most paper products with levels ranging from a few nanograms in tea bags to a few micrograms in white coffee filters. Milk containers’ paperboard contained 3-MCPD at about 500–1500 ng g–1; however, 3-MCPD was detected in milk only in smaller containers, 237–500 ml (likely due to a lower volume/surface ratio) at levels of about 1 ng g–1. Out of three disposable hot beverage paper cups tested (of 237–473 ml capacity), paperboard of two contained 3-MCPD at 632–792 ng g–1, and 3-MCPD was detected in leachate from those paper cups at levels of about 16 ng per cup. 3-MCPD was detected in all paper towels at levels of 42–2466 ng g–1. 2-MCPD was detected in many paper products (from Canadian and German sources) and in all the towels tested at levels varying from about 0.5–10% of that of 3-MCPD. [ABSTRACT FROM PUBLISHER]

• Unmodified laboratory filter paper is used for simultaneous extraction of ten basic drugs. • Simultaneous preparation of 16 samples within 90 min increases the sample throughput. • Minimal consumption of reagents, solvents and reduced waste generation. • The limit of detection as low as 0.003 µg mL−1 could be achieved. • Method has been applied for analysis of basic drugs from real blood samples. Aiming towards simplifying sample preparation procedure, the present work explores use of unmodified laboratory filter paper as sorbent for extraction of nine basic drugs (five antidepressants, four benzodiazepines, and ketamine) from human blood samples and their analysis by gas chromatography-mass spectrometry (GC-MS). The procedure termed as cellulose paper sorptive extraction (CPSE) is straightforward. It involves adsorption of target analytes from deproteinized diluted blood samples on the unmodified cellulose paper followed by elution into 2 mL of methanol. Multivariate optimization, consisting of Placket-Burman design (PBD) and central composite design (CCD), was used to screen and optimize significant factors for CPSE. The proposed method follows the principles of green analytical chemistry (GAC), as the unmodified filter paper used as the sorbent is inexpensive and biodegradable. The technique is easy to perform and requires only 2 mL of MeOH during the entire extraction procedure. Under the optimized conditions, the limit of detection and quantification for the target analytes were estimated to be in the range of 0.003–0.035 and 0.010–0.117 µg mL−1, respectively. In contrast, the relative standard deviations were consistently below 10 %. The calibration curves were linear in the range of 0.015–2 µg mL−1 with a coefficient of determination (R2) in the range of 0.995–0.999.Satisfactory recoveries ranging from 87 to 99 % was achieved. As proof of concept, the analysis of nine drugs in blood samples from the patients was performed to demonstrate the potential application of the proposed method. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA; 4,4ʹ-(propane-2,2-diyl)diphenol), a suspected endocrine disruptor with weak estrogenic activity, is used in a variety of consumer products, including paper and cardboard products used as food contact materials. The present study compared four different gas chromatographic methods for the analysis of BPA in paper and cardboard food packages. Eighteen different food packages were extracted and BPA was determined using two different derivatisation reactions – trimethylsilylation with N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA) and halide alkylation with pentafluorobenzoyl chloride (PFBOCl) – and four different separation and detection techniques. The BSTFA derivatives were quantified with (1) GC-MS in single-ion monitoring (SIM) mode with electron ionisation (EI-GC-MS) and (2) GC-MS/MS in multiple reaction monitoring (MRM) mode using electron ionisation (EI-GC-MS/MS); while the PFBOCl derivatives were quantified with (3) GC-MS using electron ionisation (EI-GC-MS) as well as (4) GC-MS with negative chemical ionisation (NCI-GC-MS). All developed methods showed good linearity (R2 > 0.9938), precision (CV < 4.5% for reproducibility; CV < 2.2% for repeatability) and sensitivity, with limits of detection (LODs) between 0.02 µg kg−1for the pentafluorobenzoyl derivatives measured with the NCI-GC-MS method and 6 µg kg−1for the pentafluorobenzoyl derivatives determined with EI-GC-MS. Levels of BPA in the samples were in agreement for all methods, ranging from values below the limit of quantitation (LOQ) to 11.9 mg kg−1paper. In a last step, the maximum potential migration into food products was calculated for all tested paper and cardboard samples, assuming a ‘worst case’ scenario of 100% migration. [ABSTRACT FROM PUBLISHER]

Copyright of Journal of Chinese Mass Spectrometry Society is the property of Journal of Chinese Mass Spectrometry Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore the effects of ventilation distribution on the releases of ketones in mainstream cigarette smoke, the releases of ketones in mainstream smoke were determined by GC-MS with two chromatography columns. The results showed that: 1) A total of 56 ketones were identified qualitatively and quantitatively. Among them, the releases of 27 ketones were more than 1 µ g/cig, and their releases accounted for more than 91% of the total release of all 56 ketones, which suggested that these 27 ketones were important in mainstream cigarette smoke. 2) Both filter ventilation rate and cigarette paper ventilation rate negatively correlated to the total release of ketones in mainstream cigarette smoke with coefficients of determination (R²) more than 0.98, and the effect of filter ventilation rate was greater than that of cigarette paper ventilation rate. 3) The ventilation rate of cigarette paper negatively correlated to the releases of 56 ketones and their total release. 4) At the same total ventilation rate of cigarette, the total release of ketones increased with the increase of cigarette filter ventilation rate, and the same total release of ketones could be achieved by different combinations of filter ventilation rate and cigarette paper ventilation rate. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) have been widely studied as potential biomarkers of cancer cells. Currently, in vitro cells are mostly cultured in two-dimen- sional (2D) adherent mode, which is different from in vivo tumor cells with three dimensional structures. Tumor cell spheres cultured in three-dimensional mode have many similar characteristics to those of in vivo tumors, such as: 1) the structure of cell spheres is divided into proliferative, quiescent, and hypoxic zones, 2) the extracellular matrix deposited in the cell spheres not only increases the density of the spheres but also affects the tumor progression by intercellular interactions. In addition, VOCs detection is mainly accomplished by gas chromatography-mass spectrometry (GC-MS) combined with solid-phase microextraction (SPME), which permits both qualitative and quantita- tive analysis of VOCs. In this present work, lung cancer cells A549 and lung epithelial cells BEAS-2B were respectively taken as examples to construct three-dimensional (3D) culture models, and 2D models and culture media were used as controls. The VOCs released from cells were detected by SPME-GC-MS. Totally. 163 VOC chromatographic peaks were included in the statistical analyses using an untargeted strategy. Based on orthogonal partial least squares discriminant analysis (OPLS-DA) with the combined criteria of Mann-Whitney U test (p<0.05) and fold change (FC2). differential VOCs released by cells in 2D and 3D culture modes were screened out. There were four VOCs of acetic acid. 1-pyrroline 4-methylheptane and 2.4-dimethyl-1-heptene released at differential levels from A549 cells cultured under 2D and 3D modes, and four VOCs of ethanol. 1-pyrroline, 4-methylheptane and 2.4-dimethyl-1-heptene released at various amounts from BEAS-2B cells cultured under 2D and 3D modes, respectively. In compar ison to 2D models. 3D models released 2.11 to 12.81 times more of these VOCs. Afterwards the possible biochemical sources of the differentially released VOCs and the possible mechanisms for the differences in the releases of VOCs in the 2D/3D models were discussed. These differentially released VOCs have been reported to be potential markers in lung cancer cells. liver cancer cells. and other biological samples in previous studies. In addition compared to 21) models 3D models can better simulate tumor growth in vise as well as cellular microenvironments including the creation of reactive oxygen species (ROS) and extracellular matrix deposition. These physiological microenvironments may promote the release of cellularly differential VOCs, In this paper. by constructing 3D cell models and analyzing differential changes in cellular VOCs. it was proved that 3D culture has a broad application prospect in the detection of cellular VOCs in vitro, and is expected to be a valuable research platform for cancer biomarker screening. [ABSTRACT FROM AUTHOR]

• An analytical protocol was developed to study water extracts from aged lacquer. • 12 New compounds were identified as aging products of lacquer. • During aging, pH, conductivity, and peak areas and indices of components changed. • Iron treatment caused the most changes in water extract while drying oil the least. Lacquered artifacts are among the most exquisite objects in museum collections. However, during aging, a considerable quantity of water-soluble products are formed on the lacquered surfaces, posing significant conservation and preservation challenges. This paper presents in-depth research on the composition of these water-soluble products by the investigation into water extracts from Asian lacquer coatings during artificial aging. Lacquer coatings of 15 specially designed formulations involving different lacquer tree saps (urushi, laccol, and thitsi), drying oils, tree resins and pigments were produced and artificially aged. A set of analytical methods was developed including pH and conductivity measurements, and peak area and index analyses based on gas chromatography–mass spectrometry (GC–MS). Results show that artificial light aging cause the formation of a complex array of hydroxyl carboxyl benzenes (Webboxy products), while simultaneously decreasing the amounts of saturated straight-chain dicarboxylic fatty acids and glycerol. Distinct changes in the average number of hydroxyls and carboxyls bonded to the benzene rings or average chain length of the dicarboxylic fatty acids have also been observed with light aging. The additive that impeded light degradation and formation of water-soluble products the most is drying oil, and the additives that accelerated composition changes of water-soluble products was iron (treatment). Additionally, 12 new compounds have been identified as aging products of lacquer, such as tetramethyl dimethoxybenzene tetracarboxylate and benzene hexacarboxylic acid hexamethyl ester. The understanding of pH and conductivity readings of water extracts from aged lacquer is significantly improved. The research results contribute to the knowledge of aging pathways and mechanisms of alteration to Asian lacquer coatings. [Display omitted] [ABSTRACT FROM AUTHOR]

The storage and use of explosives is regulated at the state and federal level, with a particular focus on physical security and rigorous accounting of the explosive inventory. For those working with explosives for the training and testing of explosive‐detecting canines, cross‐contamination is an important concern. Hence, explosives intended for use with canine teams must be placed into secondary storage containers that are new, clean, and airtight. A variety of containers meet these requirements and include screw‐top glass jars (e.g., mason jars). However, an additional need from the explosive‐detecting canine community is secondary containers that can also be used as training aids whereby the volatiles emitted by explosives are emitted in a predictable and stable manner. Currently, a generally accepted method for the storage of explosives and controlled emission of explosive vapor for canine detection does not exist. Ideally, such containers should allow odor to escape from the training aid but block external contaminates such as particulates or other volatiles. One method in use places the explosive inside a permeable cotton bag when in use for training and then stores the cotton bag inside an impermeable nylon bag for long‐term storage. This paper describes the testing of an odor permeable membrane device (OPMD) as a new way to store and deploy training aids. We measured the evaporation rate and flux of various liquid explosives and volatile compounds that have been identified in the headspace of actual explosives. OPMDs were used in addition to traditional storage containers to monitor the contamination and degradation of 14 explosives used as canine training aids. Explosives were stored individually using traditional storage bags or inside an OPMD at two locations, one of which actively used the training aids. Samples from each storage type at both locations were collected at 0, 3, 6, and 9 months and analyzed using Fourier Transform Infrared (FTIR) Spectroscopy and Gas Chromatography–Mass Spectrometry (GC–MS) with Solid‐Phase Microextraction (SPME). FTIR analyses showed no signs of degradation. GC–MS identified cross‐contamination from ethylene glycol dinitrate (EGDN) and/or 2,3‐dimethyl‐2,3‐dinitrobutane (DMNB) across almost all samples regardless of storage condition. The contamination was found to be higher among training aids that were stored in traditional ways and that were in active use by canine teams. [ABSTRACT FROM AUTHOR]

Nitrogen mustards are blistering chemical warfare agents which are considered to be persistent contaminants highly resistant to decontamination. The paper describes the development and optimization of a method for the extraction of nitrogen mustards bis(2-chloroethyl)ethylamine (HN-1), bis(2-chloroethyl)methylamine (HN-2), and tris(2-chloroethyl)amine (HN-3) from sand samples with subsequent identification by gas chromatography–mass spectrometry (GC-MS) in a military deployable laboratory. Common solvents which have been used for various methods in field analysis and are available in deployable laboratories were tested as the extraction reagents—dichloromethane, dichloroethane, hexane, heptane, ethyl acetate, methanol, and acetone. Calibration curves for the determination of nitrogen mustards were created. Methods for the extraction from the sand matrix were developed and optimized. The extraction efficiencies of the tested solvents were compared. Limits of detection of nitrogen mustards in sand samples were determined for all tested extractants. For quantitative purposes, the internal standardization method was used. The extraction efficiencies for the studied solvents varied in the range from 10.8 to 86.4%. The most effective extraction reagents for HN-1, HN-2, and HN-3 extraction were dichloromethane and acetone. Acetone was determined to be the most practical extraction reagent of nitrogen mustards in sand after the consideration of various criteria. [ABSTRACT FROM AUTHOR]

The paper analyzes the gases releasing from the furan binder samples using conventional process. For the preparation of sample sand, resin and catalyst were used in the ratio of 100:0.85:0.30. In order to increase the understanding of the gas releasing mechanism from furan binder, various studies like Fourier Transform Infrared (FTIR), Thermo Gravimetric Analysis (TGA) and Gas Chromatography-Mass Spectrometry (GC-MS) were carried out. After analyzing the materials using the above-mentioned characterizations, the chemical formula of the resin and binder was confirmed. After studying various reports on the pyrolysis process of furan binder, calculation of the percentage of various gases emitted during pyrolysis process of furan was carried out. Based on the investigation already reported in the papers, gases emitting from pyrolysis process were identified and its amounts were calculated. Based on the calculation, the total amount of gases releasing during a day was calculated and compared with the international standards of permissible gas emission limits in a foundry. [ABSTRACT FROM AUTHOR]

Copyright of Storage & Process is the property of Tianjin Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

PM2.5 is an important global air pollution issue. PM2.5 causes various problems on the environment and human health. Even though PM2.5 of the outdoor air is eliminated by particulate air filters, the chemicals adsorbed on the filtered PM2.5 can be outgassed and introduced into the semiconductor manufacturing facilities and processes, thus causing defects on the semiconductor chips by producing particles and haze as airborne molecular contamination. Therefore, estimating the amount of the outgassing from PM2.5 is a very important factor to control gaseous contaminants in the semiconductor industry. In this paper, the PM2.5 samples at different PM2.5 mass loadings were collected in Xi’an, China and evaluated using the soft X-ray radiolysis method for determining the relation between the outgassing and the PM2.5 mass loading. The PM2.5 samples were also analyzed by several methods for quantifying organic and elemental carbons, water soluble ions, and organic compounds in the PM2.5 samples. The outgassing measured by the soft X-ray method increased linearly with the PM2.5 mass loading, and the chemical analyses explained that the organic carbon (OC) was dominantly detected by the soft X-ray method in the current study. Moreover, the sampling location of the PM2.5 affected on the organic compounds of the PM2.5. [ABSTRACT FROM AUTHOR]

Tea tree hydrosol (TTH) is the aqueous phase of the distillate from the steam distillation process of the twigs and leaves of Melaleuca alternifolia. In this study, the chemical components of TTH were analyzed by gas chromatography–mass spectrometry (GC–MS) and gas chromatography–flame ionization detector (GC-FID). The major components were terpenoids (1.53 mg/mL), including monoterpenoids and sesquiterpenoids. The antibacterial activity of TTH was assessed by paper disc agar diffusion and broth dilution methods. Terpinen-4-ol (MIC: 0.31-0.62 mg/mL), 2-endo-hydroxy-1,8-cineole (MIC: 1.25-2.50 mg/mL) and p-menth-3-ene-1,2- diol (MIC: 0.62-2.50 mg/mL) were the main antibacterial components of TTH. The results showed that the major components of TTH and tea tree oil (TTO) had the same parent structures, but different degrees of oxidation. Terpinen-4-ol was the most abundant component in both TTH (624.2 μg/mL) and TTO (35-48%), and played a major role in antibacterial activities. This is the first report on the chemical components and antibacterial activities of TTH and their correlation with TTO, which demonstrates the potential application of TTH as a natural antimicrobial agent in health care products. [ABSTRACT FROM AUTHOR]

Mulberry is gaining attention for its potential health benefits. However, post-harvest deterioration of quality necessitates drying to prolong storage. This study aimed to investigate the effects of natural drying (ND), hot air drying (HAD), and vacuum freeze drying (VFD) on bioactive compounds and volatile organic compounds of fresh mulberries. The results showed that VFD had the highest retention of total phenols (5 553.87 ± 744.97 µg GAE·g-1) (GAE - gallic acid equivalent), total flavonoids (3 575.51 ± 465.98 µg rutin·g-1), and total anthocyanins (64.98 ± 13.15 µg C3C·g-1) after prolonged drying. Additionally, flavour was identified as the most important indicator influencing consumer preference for dried mulberries, and VFD was found to be effective in retaining the natural flavours of mulberries. Although thermal treatment leads to a significant loss of organic compounds, HAD showed good retention of active substances and lower energy consumption in a shorter processing time. [ABSTRACT FROM AUTHOR]

Targeted at the aged Fengxiang crude Baijiu stored in Jiuhai, a container for Chinese Baijiu, this paper adopted the gas chromatography-mass spectrometry (GC-MS) and gas chromatography-ion mobility spectrometry (GC-IMS) to analyze the changes of volatile substances in the Fengxiang Baijiu. The results indicated that 85 compounds were detected by GC-MS, including 41 esters, 10 acids, 17 alcohols, and some compounds with high molecular weight. During storage, the content of esters decreased obviously, that of acids increased, and that of higher fatty acid esters such as ethyl palmitate, ethyl linoleate, elaidic acid ethyl ester, and stearic acid ethyl ester, and phenylethyl alcohol showed a linear growth. In contrast, a total of 47 compounds, dominated by 23 esters and 14 aldehydes and ketones, were identified by GC-IMS, as it was more sensitive to substances with small molecules. It was found that the content of dipropyl sulfide, isopentane, diacetyl, etc., increased with time. The principal component analysis (PCA) of the two techniques showed that there were significant differences between aged crude Baijiu. Combining the above two techniques, a change law of the volatile components in aged Fengxiang crude Baijiu was derived, the content of acids increased, that of esters declined, and that of ethyl palmitate, ethyl linoleate, elaidic acid ethyl ester, stearic acid ethyl ester, phenylethyl alcohol, benzaldehyde, dimethyl sulfide, and lactic acid grew. It was expected that the results of this paper could provide a theoretical basis for the establishment of the aging system of Fengxiang Baijiu.

Per- and polyfluoroalkyl substances (PFAS) are a large class of organic compounds, in which all or part of the hydrogen atoms in the alkyl-chain are replaced by fluorine, and many PFAS are used globally in chemicals, leather textile, paper, packaging and other industrial and consumer goods production fields. Many studies have shown that PFAS possesses hepatic and metabolic toxicity, reproductive and developmental toxicity, immunotoxicity, and so on. Therefore, the use of PFAS in textiles has been restricted by lots of regulations or standards world widely, such as the International Ecological Textile Standard (STANDARD 100 by OEKO-TEX®), the Restricted Substances List (RSL) of the American Apparel & Footwear Association (AAFA) and the REACH regulations of EU. However, there is still lack of simultaneous determination method for various volatile PFAS in relevant standards. In this study, a method of gas chromatography-mass spectrometry (GC-MS) was developed for the simultaneous determination of 12 volatile PFAS in infant and child textiles, including four fluorotelomer alcohols (FTOHs), three fluorotelomer acrylates (FTAs), three perfluorooctane sulfonamides (FOSAs) and two perfluorooctane sulfonamidoethanols (FOSEs). The redissolve solvent was optimized, and the extraction efficiencies for different extraction solvents, extraction volumes, extraction times, extraction temperature and time were compared. 20 mL Acetonitrile was selected as extraction solvent, and the sample was extracted twice by ultrasonic at 60 ℃ for 30 min each time, then the combined supernatants were concentrated by rotary evaporation. Finally, the targets were separated by DB-5MS column and detected at selected ion monitor (SIM) mode, and quantified by external standard method. The results showed that 4∶2 FTOH and the other 11 volatile PFAS had good linear relationship in the range of 20-5 000, 10-5 000 μg/L, respectively, and the correlation coefficients (R²) were not less than 0.998. The limits of quantification (LOQs) were 0.03-0.07 mg/kg. The recoveries of 12 PFAS were 71.9%-113.6% under the two spiked levels (levels at the LOQ and the limit content of relevant standards), and the relative standard deviations (RSDs) were 1.2%-12.8% (n=6). The method has the advantages of simple pretreatment, accurate qualitative and quantitative determination, high sensitivity, and good repeatability. The actual samples were divided into two groups and determined by this method. One group included 53 pieces of textile fabrics with certain waterproofness that were tested daily in the laboratory. Some of these textile fabrics have cartoon patterns, which may be used for making children’s clothing. The other group included 26 pieces of infant and child clothes purchased from online stores. The results showed that the positive rate of volatile PFAS in textile fabrics was high. FTOHs and FTAs were detected, and their concentrations were in the range of 0.08-276.41 mg/kg. FOSAs were not detected in the samples. The textile fibers with PFAS detected were mainly polyester. Volatile PFAS were not detected in the randomly purchased infant and child cloth products, which might be mainly because they didn’t have waterproofs. The skin exposure model proposed by the European Chemical Agency was used to assess exposure risks. The mixed exposure of various PFAS in textiles was calculated by the relative potency factor (RPF), which was converted into the equivalent of PFOA, and compared with the safety threshold given by the US Environmental Protection Agency and the European Food Safety Agency. The results showed that the risk of direct health hazards to infants and children from the exposure of detected target substances was low. The method has reference value for the control of volatile PFAS risk substances in baby textiles. [ABSTRACT FROM AUTHOR]

The objective of this study was to quantify the concentration of acrylamide in biscuits, bread, and cake obtained from industrial and local bakeries, classified based on their colour intensity as light, medium, or dark. The analysis was performed using gas chromatography-mass spectrometry (GC-MS). Sugar, moisture, and asparagine analyses were also carried out simultaneously. The results demonstrated that the acrylamide content in biscuits, bread, and cakes varied according to the colour (light 109.9 ± 7.95, 214.7 ± 27.40, and 128.6 ± 7.05; medium 176.3 ± 15.16, 387.0 ± 87.71, and 804.3 ± 17.16; and dark 407.6 ± 105.13, 555.8 ± 16.20, and 1 015.0 ± 83.68 µg·kg-1, respectively). Statistically, significant differences were observed between acrylamide content and product colour density (P < 0.05). It can be concluded that the acrylamide content increases as the product colour intensity rises due to the increased baking temperature at which the reaction between reducing sugars and asparagine takes place, resulting in the formation of acrylamide. The results suggest that selecting commercial bakery products based on colour may be beneficial for reducing the daily intake of acrylamide by consumers. Therefore, it is recommended to avoid dark-coloured bakery products. [ABSTRACT FROM AUTHOR]

Drug abuse is a global menace in the society. Strict measures are planned and effectuated to dismantle this crime yet a large number of cases of narcotics drugs are seized and referred to forensic science laboratories for analysis. Over the past few years, the misuse of precursor chemicals has increased substantially. Examination of these precursor chemicals, especially ephedrine and its analogues, is a major task for forensic analysts. Though gas chromatography–mass spectrometry (GC–MS) is a well-established technique, it dwindles in the identification of the analogues of ephedrine as they have similarity in molecular weight and structure. The analysis involves time-consuming extraction and derivatization process in sample preparation when used for the identification of isomers. The present paper describes a use of high-performance thin-layer chromatography coupled with mass spectrometry (HPTLC–MS) for the purpose. This technique requires minimum sample preparation; it is a quick and easy methodology with no derivatization and gives a conclusive result for the separation and identification of ephedrine analogues. The drug samples were dissolved in methanol and spotted on Si60 F254 thin-layer chromatography (TLC) plate. Good separation of ephedrine from a mixture of ephedrine, pseudoephedrine, and phenylpropanolamine was achieved using the solvent system n-butyl acetate–acetone–n-butanol–5 M ammonia–methanol (4:2:2:1:1, v/v). The separated spot on the TLC was subjected to MS, which identified ephedrine with confirmation. [ABSTRACT FROM AUTHOR]

It is a commonly known fact that all ground beetles possess abdominal pygidial glands with relatively similar gross structure and function among species. Still, morphology of the glands and composition of their secretions have not been studied in most ground beetle species. These exocrine glands and their products are mainly associated with defence in natural environments. In this paper, we studied three predatory ground beetle species of the genus Carabus Linnaeus, 1758, namely C. (Archicarabus) montivagus Palliardi, 1825, C. (Megodontus) caelatus Fabricius, 1801, and C. (M.) violaceus Linnaeus, 1758, to identify chemical components of their pygidial gland secretions. Altogether, 10 carboxylic acids were isolated from the analysed secretions [two from the secretion of C. (A.) montivagus, 10 from that of C. (M.) caelatus, and nine from that of C. (M.) violaceus]. The finding of 2-hexenoic acid in the secretion of C. (M.) caelatus is the first finding of it within the entire subfamily Carabinae. In addition, we also analysed the morphology of glands of the species C. (M.) violaceus. [ABSTRACT FROM AUTHOR]

16 kinds of phthalate esters (PAEs) plasticizers in commonly used food contact materials were detected, and their migration rules under different contact time and temperatures were explored. The food contact materials were extracted by ultrasonic, detected by gas chromatography-mass spectrometry (GC-MS),then quantified by external standard method. Under the established method, PAEs was detected in all the nine kinds of food contact materials. Among the contents of PAEs, bis（2-n-butoxyethyl）phthalate（DEHP）was the highest, followed by dibutyl phthalate (DBP) and diisobutyl phthalate (DIBP),and their contents in plastic food contact materials were higher than those in paper materials. The migration experiment showed that 16 kinds of PAEs had a certain amount of migration under different contact time and temperatures. The PAEs migration content increased with the increase of time and temperature in the same food simulant, and the migration rate was faster in the early contact stage. The migration of PAEs in different food simulants under the same storage temperature were in the order: vegetable oil>20% ethanol>3% acetic acid>water. The safety of PAEs plasticizers in food contact materials still needs to be paid more attention to. The research can provide some theoretical basis for the safety use、 supervision of food contact materials, also can provide methodological guidance for control of food processing, production and storage process. [ABSTRACT FROM AUTHOR]

Traditionally, Laurus nobilis is used for the treatment of earaches and skin rashes as well as rheumatism. The most common technique to isolate the oil is hydro-distillation and steam-distillation. The investigation presented in this paper was aimed to unravel the antimicrobial activity and chemical composition of essential oil in the leaves of L. nobilis grown in Oman. The essential oil was extracted from the leave of the selected plant species by hydro distillation using Clevenger type apparatus. The antimicrobial assay was done by disc diffusion methods against three bacterial strains, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli, and one fungal strain: Candida albicans. The isolated essential oil was analyzed by gas chromatography-mass spectrometry (GC-MS). The percentage yield of the essential oil was 0.064% (w/w). The essential oil was found actively against the applied bacterial and fungal strains. The highest activity was found against S. aureus and the lowest was against E. coli, and the order was S. aureus > P. aeruginosa > E. coli. The essential oil was also active against the fungus C. albicans. The range of inhibition zones was 6-14 mm. The results of GC-MS analysis showed (E)-β-caryophyllene to be the major component about 59.62%. Other major components included α-selinene (14.03%), α-humulene (8.65%), β-selinene (4.99%), and α-pinene (4.98%). In addition, several minor components were found in the essential oil of L. nobilis. Based on the experimental results, it showed that the plant species that grown in Oman were a potential source of therapeutic agents. In conclusion, the essential oil and the plant could be used as natural and potential therapeutic agents to treat earaches, skin rashes, and rheumatism. [ABSTRACT FROM AUTHOR]

The application of disposable tableware has increased substantially in recent times due to the rapidly growing food delivery business in China. Synthetic phenolic antioxidants (SPAs) are widely used in food contact materials (FCMs) to delay the process of oxidation; however, their compositions, concentrations, and potential health hazards remain unclear. Therefore, FCMs comprised of five materials obtained from 19 categories (n = 118) in China were analyzed for SPAs concentrations. FCMs have been found to contain a variety of SPAs, with ∑SPAs concentrations ranging from 44.18 to 69,485.12 μg/kg (median: 2615.63 μg/kg). The predominant congeners identified in the sample include 2,4-di-tert-butylphenol (2,4-DTBP), 2,6-di-tert-butylphenol (2,6-DTBP), and 2,6-di-tert-butyl-p-benzoquinone (BHT-Q) with a median concentration of 885.75, 555.45 and of 217.44 μg/kg, respectively. Milky tea paper cups, instant noodle buckets, milky teacups, and disposable cups showed high levels of SPAs. 2,2′-methylenebis(4-methyl-6-tert-butylphenol) (AO 2246) was predominantly detected in polyethylene and polyethylene terephthalate-based products. The migration test identified disposable plastic cups and bowls as the predominant FCMs and 2,4-DTBP as the dominant SPA. The exposure risk of SPAs decreased with age. In children, the estimated daily intake of ∑SPAs from FCMs was determined to be 17.56 ng/kg body weight/day, which was 8.3 times higher than that of phthalic acid esters. The current findings indicate the potential ingestion risk of SPAs during the daily life application of multiple FCM categories. [Display omitted] • 2,4-DTBP and BHT-Q were the dominant SPAs and TPs in FCMs with high concentration. • Milky teacup, instant noodle bucket and disposable cup are major source of SPAs. • Disposable cup and bowl are the most used FCMs with the highest migrating levels. • Migration efficiency of SPAs increased as ethanol content in simulants increased. • The exposure risks for single SPAs decreased with age. [ABSTRACT FROM AUTHOR]

A method of gas chromatography-mass spectrometry (GC-MS) was established to determine the migration of dibutyl sebacate, dioctyl sebacate, diisooctyl sebacate, decanedioic acid bis(2,2,6,6-tetramethyl-4-piperidinyl)ester in water-based, acidic and alcoholic food simulants, and olive oil and chemical alternative solvents. The 95% ethanol and isooctane chemical substitution solutions were directly analyzed by GC-MS. The olive oil samples were extracted with acetonitrile followed by QuEChERS purification, and then analyzed by GC-MS. Other simulants (water, 4% acetic acid, 10% ethanol, 20% ethanol, and 50% ethanol) were extracted with n-hexane and then determined by GC-MS. The results showed that the method is well performed under optimized conditions, with the correlation coefficient (r2) greater than 0.995. The limits of detection and the limits of quantitation of the four sebacic acid ester compounds in water, 4% acetic acid, 10% ethanol, 20% ethanol, 50% ethanol, 95% ethanol, isooctane, and olive oil simulants are 0.1-0.2 mg/kg, 0.3-0.5 mg/kg, respectively. Migration experiments on plastic samples were conducted, and spiking experiments at three concentration levels of 0.30, 2.0, 4.0 mg/kg in water, 4% acetic acid, 10% ethanol, 20% ethanol, 50% ethanol, 95% ethanol, and isooctane food simulants, and three concentration levels of 0.50, 2.0, 4.0 mg/kg in olive oil food simulants were carried out. The spiking recoveries range from 92.5% to 108%, and the relative standard deviations (RSDs) are 2.4%-8.8%. The method solves the problem that decanedioic acid bis(2,2,6,6-tetramethyl-4-piperidinyl)ester cannot be extracted into n-hexane in 4% acetic acid by adjusting pH value using ammonium hydroxide, the optimal pH range was determined by comparing the responses of four targets at different pH values. QuEChERS was firstly used for migration experiments of sebacic acid esters in food contact materials to solve the turbidity and partial oil precipitation of olive oil simulants in the concentration process after extraction. By optimizing the QuEChERS filling material, the interference of organic acids, fatty acids, sugar and other impurities on the targets were reduced, producing greater separation effect of the targets. The separation efficiency of four chromatographic columns with different polarity was compared, and the DB-17HT column was selected to detect the four sebacic acid esters simultaneously. Plastics such as polypropylene, polyethylene terephthalic acid terephthalate, polyvinyl chloride, composite membranes, paper cups, recycled PET and recycled PVC were collected and migration experiments were carried out, the migration of sebacic acid esters in these plastics materials was investigated. This method is highly sensitive, precise, and accurate, fully meeting the requirement for determining the migration of the sebacic acid esters in food contact materials and their products.

The abuse of new psychoactive substances has spread around the world. Synthetic cannabinoids (SCs) is an important group. Since the first discovery of JWH-018 in Europe in 2008, SCs have multiplied rapidly and become the focus of drug control worldwide. Statistics from the Drug Intelligence and Forensic Center of the Ministry of Public Security of China showed that the proportion of SCs in suspected drug samples seized had increased from 18.5% to 72% in 2017-2019. To this, our country drug control administration department makes positive response. A series of new anti-drug policies had been introduced since 2015. Fifty-three SCs were legally controlled until the end of 2018. China had issued total ban on SCs since July 1st, 2021. However, because of the great structural variability of SCs, it is of great significance to identify the key target structures and summarize the characteristics of the common spectrum of similar drugs in judicial practice. In this paper, 27 synthetic cannabinoids were selected, including the new synthetic cannabinoids with high prevalence in recent years and potential drug structures that had not been reported but were inferred based on the structural evolution trend of synthetic cannabinoids. The method of gas chromatography-mass spectrometry (GC-MS) was used to collect data of the selected SCs under electron ionization mode (EI). The results indicated that the SCs were mainly composed of core, linker, linked group and sidechain. Among them, the core of new SCs gradually changed from formyl indole to indole/indazolamide, which would produce characteristic fragments of m/z 144, 145, respectively. The fragmentation of the linker part mainly occurred on both sides of the carbonyl group. The tertiary carbon atoms, methyl butyrate and butylamide from the linked groups led to diversified fragmentation easily. Neutral loss frequently happened in the part of sidechain, which resulted in the formation of characteristic fragments such as fluoro-butyl (m/z 74), fluoropentyl (m/z 88) and pentenyl (m/z 68). The 7 SCs prepared according to the predicted structure shared similar fragmentation pathways with the 22 SCs abused both domestically and abroad. The variation of SCs based on the structures defined in law would gradually decrease and the structural stability would be enhanced after the total ban of SCs was issued. The mass fragmentation pathway mentioned above can provide technical support for the species identification of new SCs, as well as the prevention of drug variation. [ABSTRACT FROM AUTHOR]

Microsamples are collections usually less than 50 µL, although all devices that we have captured as part of this review do not fit within this definition (as some can perform collections of up to 600 µL); however, they are considered microsamples that can be self-administered. These microsamples have been introduced in pre-clinical, clinical, and research settings to overcome obstacles in sampling via traditional venepuncture. However, venepuncture remains the sampling gold standard for the metabolic phenotyping of blood. This presents several challenges in metabolic phenotyping workflows: accessibility for individuals in rural and remote areas (due to the need for trained personnel), the unamenable nature to frequent sampling protocols in longitudinal research (for its invasive nature), and sample collection difficulty in the young and elderly. Furthermore, venous sample stability may be compromised when the temperate conditions necessary for cold-chain transport are beyond control. Alternatively, research utilising microsamples extends phenotyping possibilities to inborn errors of metabolism, therapeutic drug monitoring, nutrition, as well as sport and anti-doping. Although the application of microsamples in metabolic phenotyping exists, it is still in its infancy, with whole blood being overwhelmingly the primary biofluid collected through the collection method of dried blood spots. Research into the metabolic phenotyping of microsamples is limited; however, with advances in commercially available microsampling devices, common barriers such as volumetric inaccuracies and the 'haematocrit effect' in dried blood spot microsampling can be overcome. In this review, we provide an overview of the common uses and workflows for microsampling in metabolic phenotyping research. We discuss the advancements in technologies, highlighting key considerations and remaining knowledge gaps for the employment of microsamples in metabolic phenotyping research. This review supports the translation of research from the 'bench to the community'. [ABSTRACT FROM AUTHOR]

Meat products contain a large number of flavor compounds (mainly aroma and taste compounds), but only a few of them affect the final flavor of the product. How to isolate and identify the key aroma or taste compounds from a large number of flavor compounds is a hot issue in the research on the flavor and quality of meat products. Molecular sensory science is a systematic science that integrates analytical chemistry, food sensory evaluation and other disciplines. Its research methods can solve the above problems well. In this paper, the application of molecular sensory science in meat products and the advantages and disadvantages of different analytical techniques are summarized. Meanwhile, the evaluation methods of molecular sensory science are expounded, and the importance of recombination and deletion experiments to further confirm the key flavor components are highlighted. This review provides a certain practical reference and theoretical basis for the research in the field of meat flavor and sensory technology innovation.

To characterise the key aroma compounds of rose essential oils, five samples (Rosa damascena essential oil, Rosa centifolia essential oil, Rosa alba essential oil, Rosa rugosa cv. ‘Plena’ essential oil, Rosa xanthina Lindl essential oil) were analysed by gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS) and quantitative descriptive analysis (QDA). Thirty-nine aroma compounds were selected as key aroma compounds by GC-MS and GC-O. The aroma of rose essential oils was described by 10 sensory attributes such as honey, sweet, fermented, spicy, fruity, woody, floral, herbal, green and fresh. The partial least squares regression (PLSR) result showed the relationship between key aroma compound and characteristic aromas of rose essential oils. This paper provided a reference for the flavourists. [ABSTRACT FROM AUTHOR]

The paper presents procedures for stir bar sorptive extraction for selected priority substances that include polycyclic aromatic hydrocarbons, phenols, and benzene and its aromatic homologs. Three extraction and instrumental analysis procedures were developed for the determination of 16 compounds. The developed solid-phase extraction methods using a movable element had high recoveries above 70%. Extraction methods were optimized by selecting an appropriate time and temperature of the process, the sample pH, and stirring speed. The detection limits for the polycyclic aromatic hydrocarbons ranged from 0.33 µg/dm3 for naphthalene to 2.22 µg/dm3 for phenanthrene. Slightly higher limits of quantification were obtained for phenols: from 9.21 µg/dm3 for phenol to 0.51 µg/dm3 for 2,4,6-trimethylphenol. The highest limit of quantification for the tested compounds was obtained for benzene, with a value of 36.6 µg/dm3, while for toluene and ethylbenzene, the values did not exceed 2.7 µg/dm3. [ABSTRACT FROM AUTHOR]

Spirulina, a cyanobacterium widely used as a food supplement due to its high nutrient value, contains volatile organic compounds (VOCs). It is crucial to assess the presence of VOCs in commercial spirulina products, as they could influence sensory quality, various processes, and technological aspects. In this study, the volatile profiles of seventeen commercial spirulina food supplements were determined using headspace solid-phase microextraction (HS-SPME), coupled with gas chromatography-mass spectrometry (GC-MS). The identification of volatile compounds was achieved using a workflow that combined data processing with software tools and reference databases, as well as retention indices (RI) and elution order data. A total of 128 VOCs were identified as belonging to chemical groups of alkanes (47.2%), ketones (25.7%), aldehydes (10.9%), alcohols (8.4%), furans (3.7%), alkenes (1.8%), esters (1.1%), pyrazines (0.8%), and other compounds (0.4%). Major volatiles among all samples were hydrocarbons, especially heptadecane and heptadec-8-ene, followed by ketones (i.e., 4-(2,6,6-trimethyl-1-cyclohexen-1-yl)-3-buten-2-one, β-ionone, 2,2,6-trimethylcyclohexan-1-one), aldehydes (i.e., hexanal), and the alcohol oct-1-en-3-ol. Several volatiles were found in spirulina dietary supplements for the first time, including 6,10-dimethylundeca-5,9-dien-2-one (geranylacetone), 6,10,14-trimethylpentadecan-2-one, hept-2-enal, octanal, nonanal, oct-2-en-1-ol, heptan-1-ol, nonan-1-ol, tetradec-9-en-1-ol, 4,4-dimethylcyclohex-2-en-1-ol, 2,6-diethylpyrazine, and 1-(2,5-dimethylfuran-3-yl) ethanone. The methodology used for VOC analysis ensured high accuracy, reliability, and confidence in compound identification. Results reveal a wide variety of volatiles in commercial spirulina products, with numerous newly discovered compounds, prompting further research on sensory quality and production methods. [ABSTRACT FROM AUTHOR]

Multidrug resistance poses a danger to public health and steadily raises mortality, despite the discovery and development of a wide range of antimicrobial drugs. Developing practical solutions to address these problems has been the focus of many recent studies. In this work, we elucidate the way certain antibiotics, when coupled with other antimicrobial agents like plant extracts, can produce synergistic effects provided that each therapy targets a separate target or signaling pathway and functions via a different mechanism. Gas chromatography-mass spectrometry (GC-MS) and thin-layer chromatography (TLC) were used to identify bioactive metabolite extracts and purify plant extracts with active antibacterial qualities. The minimum inhibitory concentration (MIC) was determined using the broth microdilution method. Different 100 samples of meat (fresh, frozen Brazilian, Sudanese, and minced meat) and meat products such as pastrami, burgers, kofta, luncheon, and sausage were randomly collected from six (6) different locations in Al-Sharkia Governorate, Egypt. The associated pathogenic bacteria recovered from the isolated raw meat samples identified by microbiological, biochemical, and molecular methods is Bacillus. Clove extract was found to be the most effective and exhibited bacteriostatic and bactericidal activities against highly resistant strains of pathogenic bacteria. The plant extracts used in the study have great efficacy in reducing bacterial contamination and can be used as a safe alternative to antibiotics to avoid and control foodborne diseases. [ABSTRACT FROM AUTHOR]

Objectives: Hypertension is a chronic disease with multiple causative factors that involve metabolic disturbances and can cause various complications. However, the metabolic characteristics of hypertension at different stages are still unclear. This study aimed to explore the metabolic changes induced by hypertension at different ages. Methods: Spontaneously hypertensive rats (SHR) and Wistar Kyoto (WKY) rats were divided into four groups according to age: 5-week-old SHR (n = 6), 5-week-old WKY rats (n = 6), 32-week-old SHR (n = 6), and 32-week-old WKY rats (n = 6). Metabolites were analyzed in primary tissues (serum, heart, lung, kidney, brain, and brown adipose) using a non-targeted metabolomics approach. Results: Thirty-five metabolites and nine related metabolic pathways were identified in 5-week-old SHR, mainly related to the metabolism of amino acids. Fifty-one metabolites and seven related metabolic pathways were identified in the 32-week-old SHR, involving glycolysis, lipid, and amino acid metabolisms. Conclusion: This experiment elucidates the metabolic profile of SHR at different ages and provides a basis for predicting and diagnosing hypertension. It also provides a reference for the pathogenesis of hypertension. [ABSTRACT FROM AUTHOR]

Mass spectrometry has been the "gold standard" for drugs of abuse (DoA) analysis for many decades because of the selectivity and sensitivity it affords. Recent progress in all aspects of mass spectrometry has seen significant developments in the field of DoA analysis. Mass spectrometry is particularly well suited to address the rapidly proliferating number of very high potency, novel psychoactive substances that are causing an alarming number of fatalities worldwide. This review surveys advancements in the areas of sample preparation, gas and liquid chromatography‐mass spectrometry, as well as the rapidly emerging field of ambient ionization mass spectrometry. We have predominantly targeted literature progress over the past ten years and present our outlook for the future. © 2020 Periodicals, Inc. Mass Spec Rev [ABSTRACT FROM AUTHOR]

[Objectives] To study the volatile components and antibacterial effects of 11 kinds of Aurantii Fructus Immaturus processed products. [Methods] 11 kinds of Aurantii Fructus Immaturus processed products were obtained according to the traditional processing method, the volatile oil was extracted by steam distillation, and the composition of volatile oil in the 11 kinds of processed products was analyzed by gas chromatography-mass spectrometry（GC-MS）. the relative percentage content of each component in these 11 kinds of processed products was determined using the peak area normalization. The drug sensitivity activity of the volatile oil of these 11 kinds of processed products was tested using the K-B paper diffusion method and the minimum inhibition volume fraction of volatile oil of these 11 kinds of processed products was tested using the microdilution method. [Results] The highest yield of volatile oil of 11 kinds of these processed products was baking（5.193%）, and the lowest was stir-bake to scorch（1.998%）. A total of 36 chemical components were identified from the volatile oils of these 11 kinds of processed products. The components with the most volatile oil were stir-bake to scorch（24 kinds）, and the components with the least volatile oil were the method of processing with rice-washed water（15 kinds）. They contain 8 kinds of common chemical components, such as limonene, linalool, myrcene, α-pinene. The highest content of limonene came from processing with honey（60.93%）, the lowest came from processing with rice-washed water（55.25%）; the highest content of linalool came from processing with rice-washed water（7.139%）, the lowest came from processing with honey（5.436%）; the highest content of myrcene came from processing with honey（1.899%）, the lowest came from stir-bake to scorch（1.632%）; the highest content of α-pinene came from raw Aurantii Fructus Immaturus（2.355%）, and the lowest came from stir-bake to scorch（1.618%）. The volatile oil of these 11 kinds of Aurantii Fructus Immaturus processed products has good antibacterial effect on Escherichia coli and Staphylococcus aureus. [Conclusions] The oil yields of volatile oils of 11 kinds of Aurantii Fructus Immaturus processed products are different, the content of limonene is significantly different, and the changes of other chemical components and their contents are not significantly different. The volatile oil of 11 kinds of Aurantii Fructus Immaturus processed products has certain antibacterial effect. [ABSTRACT FROM AUTHOR]

Edible oils play a tremendous role in the human diet. The production and consumption of edible oils have extensively increased due to their nutritional and economic significance. As a result of exponential population growth, the demand for edible oil has prompted adulteration, which has become a global crisis. Adulteration causes a variation in the fatty acid profiles, unique to each oil. The addition of adulterants is associated with gallbladder cancer, epidemic dropsy, cardiovascular diseases, hypercholesterolemia, and several other life-threatening diseases. Hence, monitoring the purity of edible oils at regular intervals has become inevitable. This study is to evaluate the quality of edible oils such as sesame, groundnut, coconut, mustard, sunflower, soybean, and olive oils by screening their fatty acids and secondary metabolites composition using gas chromatography-mass spectrometry (GC–MS) and thereby identifying the adulterants in comparison between the unrefined and refined oils. The fatty acid profiles of the unrefined oils were found to be in accordance with the literature survey, whereas the commercially available refined oils were mainly adulterated with palmitic, palmitoleic, stearic, and myristic acids. Contrastingly, numerous health-promoting secondary metabolites have been detected in unrefined oil samples. In conclusion, unrefined oils have nutritional values, and authenticity used for human consumption rather than refined edible oils. [ABSTRACT FROM AUTHOR]

The rising concerns regarding antibiotic resistance and the harmful effects of synthetic preservatives have led to an increasing interest in exploring natural alternatives. Plant oils have been traditionally used for their antimicrobial properties, but systematic investigations into their efficacy against foodborne pathogens are necessary for potential applications in food preservation. This study aimed to evaluate the antibacterial potential of various plant oils (neem, coconut, castor, and olive oil) against common foodborne pathogens and analyze their chemical composition using gas chromatography–mass spectrometry (GC-MS). The oils were tested against foodborne pathogens using the disk diffusion method. Minimum inhibitory concentrations (MICs) were determined to assess the potency of the oils. GC-MS was employed to identify the compounds present in each oil. Neem oil exhibited significant antibacterial activity against all tested pathogens, with pronounced effects against Staphylococcus aureus and Bacillus cereus. Coconut oil showed notable activity against Listeria monocytogenes. Castor oil displayed moderate activity, while olive oil exhibited minimal antibacterial effects. The GC-MS analysis revealed a diverse array of compounds in neem oil, which is likely to contribute to its potent antibacterial properties. Neem and coconut oils, owing to their rich bioactive components, emerged as promising candidates for the development of natural antimicrobial agents. These brief findings support the potential application of plant oils in food preservation and emphasize the need for further research into understanding the underlying mechanisms and optimizing their use. [ABSTRACT FROM AUTHOR]

Highlights • PLE technique was applied to alga collected in Galicia (Spain). • The FA identification and quantification was performed by GC–MS. • The applied PLE method allowed to enrich USFA from L. ochroleuca alga. • New technology to obtain high quality FAs and phenols from L. ochroleuca is provided. Abstract The increase of pathologies like cardiovascular diseases, obesity or diabetes due to the nature of diet is a matter of concern in our society. Because of this, there is a high interest in healthy natural products that could prevent the appearance of such diseases. This paper aims to study the content of fatty acids (FAs) and phenolic compounds of brown alga Laminaria ochroleuca (L. ochroleuca) and to determine the nutritional quality of the lipids extracted using pressurized liquids extraction (PLE) technique. PLE was applied to the algae using four solvents of different polarity (hexane, ethyl acetate, ethanol and ethanol:water 1:1). Results showed that the higher yield (52%), is obtained with ethanol: water solvent, however, both ethyl acetate and ethanol enrich unsaturated fatty acid (USFA) (palmitoleic, linolenic, linoleic, oleic, araquidonic and eicosapenataenoic) in the lipid fraction of L. ochroleuca, providing extracts up to 55% of their total fatty acid content compared to other solvents. The nutritional quality of the lipids in all PLE extracts was assessed by considering the ω-6/ ω-3 fatty acid ratio and two dietary indexes involved in the risks of coronary heart disease, atherogenic (AI) and thrombogenic (TI). The lower (best) index values are for ethanol extract, 4.4 (ω-6/ ω-3), 0.74 (AI) and 1.05 (TI), followed of ethyl acetate, 4.4 (ω-6/ ω-3), 0.87 (AI) and 1.24 (TI). Finally, the antioxidant capacity of PLE alga extracts in terms of total phenol content (TPC) was analyzed by the Folin-Ciocalteu method. The ethanol: water extracts showed the highest TPC with a concentration up to 173.65 mg eq. gallic acid / g PLE extract. [ABSTRACT FROM AUTHOR]

Highlights • This method has a low detection limit and an excellent linear correlation. • It is not affected by the chemical properties of the organic solvents. • This method is very environmentally friendly and saves reagents. Abstract This paper describes the development of a novel gas chromatography-mass spectrometry-selected ion monitoring (GC/MS-SIM) method for the determination of trace water contents of organic solvents, using the characteristic m/z 18, m/z 17, and m/z 16 ions of H 2 O as the qualitative ion and the m/z 18 ion as the quantifier ion. The accuracy and precision of this method were validated. An excellent linear correlation was obtained for trace water contents between 0 and 0.5217 wt%, with a correlation coefficient (R 2) of 0.9999, in addition to spike recoveries of 82.6–112.6%, and relative standard deviations (n = 6) of 0.4–7.2%. The limit of detection (S/N = 3) and limit of quantitation (S/N = 10) for the trace water contents of organic solvents were 0.0005% wt% and 0.0016% wt%, respectively.The analytical results confirmed that this method was useful for determining the trace water contents of organic solvents, because it has a low detection limit and wide linear range. It requires only small amounts of the samples and enables sample batch analysis. It is very environmentally friendly and saves reagents. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are a large class of organic compounds, in which all or part of the hydrogen atoms in the alkyl-chain are replaced by fluorine, and many PFAS are used globally in chemicals, leather textile, paper, packaging and other industrial and consumer goods production fields. Many studies have shown that PFAS possesses hepatic and metabolic toxicity, reproductive and developmental toxicity, immunotoxicity, and so on. Therefore, the use of PFAS in textiles has been restricted by lots of regulations or standards world widely, such as the International Ecological Textile Standard (STANDARD 100 by OEKO-TEX®), the Restricted Substances List (RSL) of the American Apparel & Footwear Association (AAFA) and the REACH regulations of EU. However, there is still lack of simultaneous determination method for various volatile PFAS in relevant standards. In this study, a method of gas chromatography-mass spectrometry (GC-MS) was developed for the simultaneous determination of 12 volatile PFAS in infant and child textiles, including four fluorotelomer alcohols (FTOHs), three fluorotelomer acrylates (FTAs), three perfluorooctane sulfonamides (FOSAs) and two perfluorooctane sulfonamidoethanols (FOSEs). The redissolve solvent was optimized, and the extraction efficiencies for different extraction solvents, extraction volumes, extraction times, extraction temperature and time were compared. 20 mL Acetonitrile was selected as extraction solvent, and the sample was extracted twice by ultrasonic at 60 ℃ for 30 min each time, then the combined supernatants were concentrated by rotary evaporation. Finally, the targets were separated by DB-5MS column and detected at selected ion monitor (SIM) mode, and quantified by external standard method. The results showed that 4∶2 FTOH and the other 11 volatile PFAS had good linear relationship in the range of 20-5 000, 10-5 000 μg/L, respectively, and the correlation coefficients (R2) were not less than 0.998. The limits of quantification (LOQs) were 0.03-0.07 mg/kg. The recoveries of 12 PFAS were 71.9%-113.6% under the two spiked levels (levels at the LOQ and the limit content of relevant standards), and the relative standard deviations (RSDs) were 1.2%-12.8% (n=6). The method has the advantages of simple pretreatment, accurate qualitative and quantitative determination, high sensitivity, and good repeatability. The actual samples were divided into two groups and determined by this method. One group included 53 pieces of textile fabrics with certain waterproofness that were tested daily in the laboratory. Some of these textile fabrics have cartoon patterns, which may be used for making children’s clothing. The other group included 26 pieces of infant and child clothes purchased from online stores. The results showed that the positive rate of volatile PFAS in textile fabrics was high. FTOHs and FTAs were detected, and their concentrations were in the range of 0.08-276.41 mg/kg. FOSAs were not detected in the samples. The textile fibers with PFAS detected were mainly polyester. Volatile PFAS were not detected in the randomly purchased infant and child cloth products, which might be mainly because they didn’t have waterproofs. The skin exposure model proposed by the European Chemical Agency was used to assess exposure risks. The mixed exposure of various PFAS in textiles was calculated by the relative potency factor (RPF), which was converted into the equivalent of PFOA, and compared with the safety threshold given by the US Environmental Protection Agency and the European Food Safety Agency. The results showed that the risk of direct health hazards to infants and children from the exposure of detected target substances was low. The method has reference value for the control of volatile PFAS risk substances in baby textiles.

Some aromatic amines (AA) have been classified as carcinogens to humans. After entering the body, mainly through tobacco smoke, they can be detected in urine. Thus, their trace analysis as biomarkers in biofluids is of high relevance and can be achieved with gas chromatography (GC–MS), usually after derivatization. This study compares three gas chromatographic methods for the analysis of ten iodinated derivatives of AA: GC–MS in single-ion monitoring (SIM) mode with (1) electron ionization (GC-EI-MS) and (2) negative chemical ionization (GC-NCI-MS), and (3) GC-EI-MS/MS in multiple reaction monitoring (MRM) mode using electron ionization. All methods and most analytes showed good coefficients of determination (R2 > 0.99) for broad linear ranges covering three to five orders of magnitude in the picogram-per-liter to nanogram-per-liter range, with one and two exceptions for (1) and (2) respectively. Excellent limits of detection (LODs) of 9–50, 3.0–7.3, and 0.9–3.9 pg/L were observed for (1), (2), and (3) respectively, and good precision was achieved (intra-day repeatability < 15% and inter-day repeatability < 20% for most techniques and concentration levels). On average, recoveries between 80 and 104% were observed for all techniques. Urine samples of smokers and non-smokers were successfully analyzed, and p-toluidine and 2-chloroaniline could be found at significantly (α = 0.05) higher concentrations among smokers. [ABSTRACT FROM AUTHOR]

Light is a crucial factor affecting plant growth and development. Besides providing the energy for photosynthesis, light serves as a sensory cue to control the adaptation of plants to environmental changes. We used the etiolated maize (Zea mays) seedlings as a model system to study the red light-regulated growth. Exposure of the maize seedlings to red light resulted in growth inhibition of mesocotyls. We demonstrate for the first time (to the best our knowledge) that red light affected the patterns of apoplastic fluid (AF) metabolites extracted from the mesocotyl segments. By means of the untargeted gas chromatography-mass spectrometry (GC-MS)-based metabolomics approach, we identified 44 metabolites in the AF of maize mesocotyls and characterised the dynamics of their relative tissue abundances. The characteristic metabolite patterns of mesocotyls dominated with mono- and disaccharides, organic acids, amino acids, and other nitrogen-containing compounds. Upon red light irradiation, the contents of β -alanine, putrescine and trans -aconitate significantly increased (P -value < 0.05). In contrast, there was a significant decrease in the total ascorbate content in the AF of maize mesocotyls. The regulatory role of apoplastic metabolites in the red light-induced inhibition of maize mesocotyl elongation is discussed. Light is a crucial factor affecting plant growth and development. Besides providing the energy for photosynthesis, light serves as a sensory cue to control the adaptation of plants to environmental changes. Exposure of the maize (Zea mays) seedlings to red light resulted in growth inhibition of growing mesocotyls and decreased the total ascorbate contents. Red light also affected the primary metabolite patterns in mesocotyl apoplastic fluid. Among metabolites, the contents of β-alanine, putrescine and trans -aconitate significantly increased. Our results get a new insight into the mechanisms of red light-induced growth inhibition in plants. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effect of two mycorrhizal fungi, Funneliformis mosseae (Fm) and Rhizophagus intraradices (Ri), on capsaicinoid production in Capsicum annuum L. by gas chromatography-mass spectrometry (GC-MS) via two different extraction approaches, magnetic stirring and ultrasound-assisted extraction with three different solvents, ethanol (EtOH), ethyl acetate (EtAce), and acetonitrile (AceN). The effect of mycorrhizal fungi on some physiological properties and biochemical activity, the content of total phenolic compounds, and antioxidant activity were also investigated. For all investigated parameters, the plants inoculated with mycorrhizal fungi showed significantly higher values than the non-mycorrhizal control plants, except for malondialdehyde (MDA), which was an indicator of lipid peroxidation due to damage that occurred in the cell membrane. It was concluded that inoculation with mycorrhizal fungi increased both capsaicin and dihydrocapsaicin production up to 4-fold in C. annuum compared to the control. Results also indicated that ultrasound-assisted extraction with EtAce was the most effective method for the determination of capsaicin by GC-MS. [ABSTRACT FROM AUTHOR]

Mushroom extracts have shown potential as a source of new antimicrobial agents. This study investigates the chemical profile of an aqueous ammonia extract obtained from the carpophores of Ganoderma lucidum, which grows on Quercus ilex trees, and explores its valorization as a biorational. The major chemical constituents of the extract, identified through gas chromatography–mass spectrometry, include acetamide, oleic acid, 1,2,3,4-butanetetrol, monomethyl azelate, undecane, and palmitic acid. The anti-oomycete and antifungal activity of G. lucidum extract was evaluated against Phytophthora cinnamomi, the primary threat to Quercus spp. in the dehesa biome, as well as three Botryosphaeriaceae fungi. In vitro tests revealed minimum inhibitory concentration (MIC) values of 187.5 μg·mL−1 against P. cinnamomi and 187.5–1000 μg·mL−1 against the fungi. Furthermore, conjugation of the G. lucidum extract with chitosan oligomers (COS) synergistically enhanced its antimicrobial activity, resulting in MIC values of 78.12 and 375–500 μg·mL−1 against P. cinnamomi and the fungi, respectively. These MIC values are among the highest reported to date for natural products against these phytopathogens. Subsequent ex situ testing of the COS-G. lucidum conjugate complex on artificially inoculated Q. ilex excised stems resulted in high protection against P. cinnamomi at a dose of 782 µg·mL−1. These findings support the potential utilization of this resource from the dehesa ecosystem to protect the holm oak, aligning with sustainable and circular economy approaches. [ABSTRACT FROM AUTHOR]

Herbivore-Induced Plant Volatiles (HIPVs) are volatile signals emitted by plants to deter herbivores and attract their natural enemies. To date, it is unknown how lychee plants, Litchi chinensis, respond to the induction of leaf galls (erinea) caused by the lychee erinose mite (LEM), Aceria litchii. Aiming to reveal the role of HIPVs in this plant-mite interaction, we investigated changes in the volatile profile of lychee plants infested by LEM and their role on LEM preferences. The volatile profile of uninfested (flower buds, fruit, leaves and new leaf shoots) and infested plant tissue were characterized under different levels of LEM infestation. Volatiles were collected using head-space-solid phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analyses. Fifty-eight volatiles, including terpenoids, alcohols, aldehydes, alkanes, esters, and ketones classes were identified. Using dual-choice bioassays, we investigated the preference of LEM to uninfested plant tissues and to the six most abundant plant volatiles identified. Uninfested new leaf shoots were the most attractive plant tissues to LEM and LEM attraction or repellence to volatiles were mostly influenced by compound concentration. We discuss possible applications of our findings in agricultural settings. [ABSTRACT FROM AUTHOR]