Gas Chromatography-mass Spectrometry Method Research Articles

Potential of dragon’s blood fruit (Calamus draco) as a class I preservative agent and additive ingredient to improve the quality of whole coconut VCO (Virgin coconut oil)

The method developed uses whole coconut as the raw material for making VCO through an easy-to-apply fermentation process, adding dragon’s blood fruit extract in concentrations of 0%, 20%, 40%, 60%, and 80%. Peroxide and iodine numbers were tested as parameters of VCO quality. The gas chromatography mass spectrometry (GCMS) method was used to analyze the fatty acid profile of VCO after transesterification. The results showed that the highest total saturated fatty acid content of 97.28% was found in the VCO sample with a 40% concentration of dragon’s blood fruit, and the unsaturated fatty acid profiles detected in the VCO included palmitoleic acid, methyl linoleic, and methyl oleic. The addition of dragon’s blood fruit can also reduce the peroxide number and increase the iodine number in accordance with SNI 7381-2008, which is below the maximum limit of the VCO peroxide number of 2.0 mEq/kg of oil while the iodine number of the VCO is in the range of 4.1–11 g iodine/100g. It can be concluded that a 40% dragon’s blood fruit concentration can improve the quality of VCO preservation.

Development and validation of a quantitative method for the analysis of delta-9-tetrahydrocannabinol (delta-9-THC), delta-8-tetrahydrocannabinol (delta-8-THC), delta-9-tetrahydrocannabinolic acid (THCA), and cannabidiol (CBD) in botanicals, edibles, liquids, oils, waxes, and bath products by gas chromatography mass spectrometry (GC/MS).

A quantitative gas chromatography mass spectrometry (GC/MS) method was developed for delta-9-tetrahydrocannabinol (delta-9-THC), delta-8-tetrahydrocannabinol (delta-8-THC), tetrahydrocannabinolic acid (THCA), and cannabidiol (CBD) in matrices including plant material, liquids and oils, waxes, edibles, and bath and body products. Samples were prepared by homogenization, extraction of the cannabinoids into solvent, liquid/liquid extraction, and derivatization. The GC/MS method was validated from 0.15% to 5.00% (weight basis) to encompass the 0.3% legal distinction between hemp and marijuana. Validation was performed assessing imprecision/bias, calibration model, recovery, interferences, limit of detection, matrix matching, carryover, accuracy, and an assessment of CBD conversion to delta-9-THC. The calibration curves were quadratic weighted 1/x with r2 > 0.990. The method had a detection limit of 0.075% in plant material for each analyte. Analyte recovery was greater than 70% in plant material. Carryover was not observed up to concentrations equivalent to 100% analyte, and no forensically significant conversion of CBD to delta-9-THC was observed. One cannabinoid isomer, 9(R)-delta-7-tetrahydrocannabinol (9(R)-delta-7-THC), was determined to interfere with the quantitation of delta-9-THC, but could be differentiated based on mass spectrum. The method was determined to be suitable for quantitation of delta-9-THC, delta-8-THC, delta-9-THCA, and CBD and was able to differentiate hemp samples from marijuana samples.

Determination of eleven components in rat plasma by UPLC-MS/MS and GC-MS for pharmacokinetic studies after oral administration of Citri Reticulatae Pericarpium extract

Citri Reticulatae Pericarpium (CRP) is used as common health-care food and traditional Chinese medicine (TCM), which exerts pharmacological effects, such as anti-cardiovascular, anti-tumor, anti-oxidant, anti-inflammatory, anti-virus, hepatoprotective, blood pressure-lowering and neuroprotective. In this study, reliable, and sensitive ultra-high performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) methods were developed and validated for the determination of eleven active components in rat plasma after oral administration of the CRP extract. The results of this method exhibited that the specificity, linearity (r > 0.999), precision and accuracy (the coefficient of variation (CV) < 11.5 %), recovery (52.9–107.9 %), matrix effects (63.8–107.5 %), and stability (CV < 10.8 %) met all requirements for the quantitation of plasma samples. The pharmacokinetic results showed that the Tmax of flavone glycosides was less than 0.7 h, and that of polymethoxyflavones and volatile components were within 1–7 h. Meanwhile, the area-under-the-curve (AUC) and concentration maximum (Cmax) of hesperidin, nobiletin, tangeretin, and D-limonene were higher than those of the other components, suggesting that the plasma exposure levels of these constituents were higher in CRP. The present research lays a foundation for elucidating the therapeutic material basis and provides a reference for further scientific research and clinical application of CRP.

Identification of Bioactive Secondary Metabolites in Citronella Grass Leaves (Cymbopogon nardus L.) against Curvularia andropogonis

Citronella grass (Cymbopogon nardus) is an essential oil-producing plant. The essential oils consist of geraniol and citroneal whose production is affected by plant health. The production of citronella grass decreases (harvest loss) due to red spot disease caused by Curvulaia andropogonis infection which also affects the bioactive composition of secondary metabolites. Defense signal responses are also generated using plant defense pathways which result in compounds used for counterattacking plant invasions. The purpose of this study was to determine the secondary metabolites of C. nardus attacked by C. andropogonis. This research used HPLC to analysis citronellol and geraniol C. nardus with normal, wound and infected treatment. The Gas Chromatography-Mass Spectrometry (GCMS) method was used to detect metabolites profiles in normal treatment, injury, and infection, and then analyzed based on metabolite groups and metabolic pathways. The result of this study indicated that the citronellol in normal treatment sample was higher, namely 102.003mg/L compared to the wound treatment, which was 100.120mg/L and the infected treatment, which was 89.356mg/L. Likewise for geraniol in the normal treatment of 20.065mg/L, which is greater than the wound treatment, which was 19.245 mg/L and the infected, which was 15.765mg/L. There were 12 types of metabolites based on chemical grouping including alkaloids, carboxylic acids, fatty acids, flavonoids, nucleic acids, phenolics, terpenoids, alcohols, aldehydes, amino acids, heterocyclic compounds, and carbohydrates. The highest metabolites were found in carboxylic acid. Metabolic pathways resulted carboxylic acids which came from 2-Oxocaboxylic acid metabolism, and phenolics came from the biosynthesis of secondary metabolites, which were highest in carbohydrate metabolism. In conclusion, almost all metabolites and metabolic pathways increase in the infection treatment which was significant with the results of citronellol and geranioldecreased so that the overall content of bioactive secondary metabolites decreased.

Sustainable Technique for Neem (Azadirachta Indica) Seed Oil Extraction: Optimization and Characterization

N-hexane is a solvent that is frequently used in oil extraction processes. But there is enough data to demonstrate this solvent's harmful nature. In this study, the Soxhlet process was utilized to extract neem seed oil from neem seeds using a greener petroleum ether. We looked into how the temperature (25–125 °C) and time variation (30–50 min) affected the extraction process. When the temperature is held constant, it indicates a high yield (57.08%) at 150 minutes and a maximum yield (52%) at 125°C when the duration is held constant. An examination of the saturated and unsaturated fatty acids' makeup was done using the gas chromatography-mass spectrometry (GC-MS) method. The result of the GC-MS method showed a high proportion of unsaturated fatty acids (58.82%), which are important because they may provide health benefits when included in a balanced diet. Alkaloids, coumarins, terpenoids, saponins, steroids, flavonoids, and triterpenoids are all present, with the exception of tannins, according to the phytochemical analysis. This implies that the oil may have therapeutic value. The extracted oil exhibits the following characteristics: 3.53% moisture content, 1.70 mg KOH/g acid value, 0.81 density (g/cm3), 31.60 viscosity (mm2/s), 268 mg KOH/g saponification value, 3.71% ash content, and 119.8 mg I2/100g iodine value. These figures illustrate the oil's potential for use in a variety of multi-industrial applications; they are compliant with ASTM standards.

Comparison of Chemical Constituents of Some Plant Species of Lamiaceae Family Grown Conventionally and Organically

In this study, the chemical constituents of Origanum onites, Salvia officinalis and Lavandula officinalis plants belonging to Lamiaceae family grown by conventional and organic methods were determined by soxhlet extraction. Gas Chromatography-Mass Spectrometry (GC-MS) method was used to determine the chemical constituents of conventionally and organically grown plant samples. When the results of the analyses were examined, out of 97 chemical components of Salvia officinalis plant, 50 components were determined from plants grown with conventional farming methods and 78 components were determined from plants grown with organic farming methods. Of the 38 components detected in Origanum onites, 36 components were determined from plants grown with conventional farming methods and 38 components were determined from plants grown with organic farming methods. Out of 60 components of Lavandula officinalis, 40 components were determined from plants grown with conventional farming methods and 60 components were determined from plants grown with organic farming methods. In terms of chemical structure, the components are divided into different classes as hydrocarbons, monoterpenes, monoterpenoids, sesquiterpenes, sesquiterpenoids, diterpenes, diterpenoids, fatty acids and derivatives, and phenolic compounds.

GC-MS method for simultaneous determination and pharmacokinetic investigation of five volatile components in rat plasma after oral administration of the essential oil extract of Pogostemoncablin

Pogostemon cablin (PC) is a traditional Chinese medicine (TCM) and food as well as an important essential oil plant in China. PC essential oil exerts pharmacological effects such as anti-inflammatory, anti-oxidant, anti-platelet, anti-thrombotic, and anti-depressant. This study established a reliable and sensitive gas chromatography-mass spectrometry (GC-MS) method for the simultaneous determination of the pharmacokinetics of patchouli alcohol, β-elemene, β-caryophyllene, caryophyllene oxide, and farnesol in the plasma of rats after oral administration of PC essential oil extract. Using ethyl acetate to prepare the plasma samples, and p-menthone was used as the internal standard (IS). An HP5-MS column (0.25 μm × 0.25 mm × 30 m) was used for chromatographic separation, and detection was performed in selected ion monitoring (SIM) mode. The accuracies of intra-day and inter-day for all analytes displayed a range of −6.7 %–9.2 %, with precision below 12.5 %. Extraction recoveries for analytes ranged from 74.0 to 106.4 % and matrix effects ranged from 92.4 to 106.9 %. Stability results have demonstrated that the relative standard deviations (RSD) of analytes were below 12.1 %. Therefore, the developed GC-MS method successfully evaluated the pharmacokinetics of five volatile components in PC essential oil extract administered orally to rats.

Synergistic effect of essential oil of thyme extract (EOT) with chemotherapy in esophageal cancer cells

Background: Esophageal cancer is one of the most common causes of cancer-related death in various countries around the world, and thus represents a major global health challenge. This cancer is most often found in the upper and middle parts of the esophagus but can occur anywhere along the length of the esophagus. Aim of study: Essential oils have activity that targets cancer cells and their ability to increase the effectiveness of commonly used chemotherapy, including cisplatin, as they act as antioxidants when given to a cancer patient. Methods: In this study, the volatile oil of Thymus was extracted from the dry leaves of the plant and EOT was detected by the gas chromatography mass spectrometry (GS-MS) method. Cytotoxicity was evaluated by two experiments, one to determine the effect of volatile oil on the esophageal cancer cell line (SKG-4) and to compare chemotherapy when combined with the extract.Results: Essential oil cytotoxicity in 48 hours showed a significant percentage (P &lt; 0.05) at all diluted volumes used, while the highest toxicity (89.016%) was in the diluted volume of 2.5 μl/ml. The same results were also observed for the combination of EOT, and chemotherapy cisplatin used during the trial. A significant percentage (P &lt; 0.05) within 72 hours was observed to show the highest cytotoxicity (70.191%) in the diluted volume of 10 μl/ml, and no difference appeared in cytotoxicity. Conclusions Through this experiment, we concluded that the extract has a toxic effect on the cancer cell line and does not affect the effectiveness of chemotherapy and that the aim of this study is to mitigate the negative effects of chemotherapy.

Effects of Pelletized and Coated Organic Fertilizers on Flavor Compounds of Tomato Fruits and Leaves.

The application of organic fertilizers is one of the most important agricultural measures aimed at improving the flavor and productivity of Lycopersicon esculentum, with the granulation and coating of organic fertilizers, which can reduce seepage losses of great significance to the ecosystem. In this study, Jingcai 8 tomato was selected as the test material. Headspace solid-phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GC-MS) methods were used to investigate the effects of different pelletized organic fertilizers and various coating materials on the flavor profile of the tomatoes. The results indicated that 67 volatile organic compounds (VOCs) were identified in the tomato fruits and 62 volatile compounds were identified in the leaves under different fertilizer treatments. The volatile compound content of the fruits in the BP treatment group was 35.38 μg/g, which was higher than that in other treatment groups, and the volatile compound content of the leaves was lower. A differential compound analysis with log2|fold change| ≥ 1 and variable important in projection (VIP) > 1 highlighted styrene, 3-methyl-1-butanol, and (E, E)-2,4-hexadienal as the major up-regulated compounds and methyl salicylate as the major down-regulated compound in the tomato fruit BCK (control) vs. BP. Moreover, the α-phellandrene content decreased in the tomato leaves. In addition, an analysis of the tomato fruit differential compounds and compounds with odor activity values (OAV) of ≥ 1, considering the OAV values of characteristic aroma compounds, identified key compounds affecting the flavor of the tomato fruits under the BP treatment. These included 2-nonenal, (E)-2-pentylfuran, trans-β-ionone, 1-penten-3-one, (E, E)-2,4-hexadienal, and 3-hexenol (fruity, floral, and herbaceous odors), (E, E)-2,4-heptadienal (fatty odor), and hexanal (green odor). The combined results analysis of the volatile compound content, differential compounds, and OAV values of characteristic aroma compounds aimed to clarify that the BP treatment group, which applied pelletized, large-grain organic fertilizer with polyurethane (pozzolanic + small-grain oil-coated + 2% paraffinic + 4% polyurethane) as a coating material, proved to be most effective in influencing the flavor of the tomato fruits. This finding lays the foundation for its potential commercial application in artificial orchards.

Phytochemicals, Antioxidant, and Antidiabetic Effects of Ranunculus hirtellus Aerial Parts and Roots: Methanol and Aqueous Extracts.

Ranunculus hirtellus, also known as crowfoot (buttercup), has a rich tradition of use in various biological contexts. While antibacterial studies on extracts from this plant have been conducted, the phytochemical composition, antioxidant properties, and antidiabetic effects remain unexplored. In this study, the phytochemical, antioxidant, and antidiabetic effects of its methanol and aqueous extracts were investigated. Our approach involved gas chromatography-mass spectrometry (GC/MS), alongside quantitative and qualitative methods, for phytochemical profiles. Additionally, concerning biological activities, the antioxidant effect was assessed through 2, 2-diphenyl-pieryl hydrazyl (DPPH) and 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonate) (ABTS) assays, while the antidiabetic effect was examined through the α-amylase inhibitory assay. The chloroform, ethyl acetate, and n-hexane extracts of R. hirtellus revealed the presence of 14 distinct compounds. In the methanol extract, sterols, quinones, glycosides, lactones, lignin, and flavonoids were identified. The aqueous extract contained sterols, alkaloids, glycosides, triterpenes, terpenoids, quinones, leucoanthocyanins, and lactones. The total flavonoid content (TFC), total phenolic content (TPC), total tannin content (TTC), and reducing sugar content (RDC) were determined in plant extracts, and a linear relationship was found between these parameters. Additionally, the TTC, TPC, and TFC values for both extracts hovered around 0.3786, 0.0476, and 0.1864 μg/mL, respectively, across all plant concentrations, while RDC ranged from 0.9336 to 1.0119 μg/mL in all four extracts. In vitro assays demonstrated dose-dependent antidiabetic activity in both methanolic and aqueous extracts by inhibiting α-amylase. Furthermore, the antioxidant activity observed in the DPPH assay was greater in the aqueous extract compared with the methanolic extract. In addition, the ethyl acetate extract exhibited the highest inhibition among chloroform and n-hexane in the ABTS assay. The results suggest that R. hirtellus can be a potential source of natural antioxidants and antidiabetic agents, and further studies are warranted to investigate the underlying mechanisms of its therapeutic effects.

Chemical composition of leaf essential oil of Schinopsis lorentzii and its inhibitory effects against key enzymes relevant to type-2 diabetes: an emphasis on GC-MS chemical profiling and molecular docking studies

Schinopsis lorentzii (Griseb.) Engler is an aromatic plant belonging to Anacardiaceae family, and grown in Argentina, Paraguay, Brazil, and Bolivia. It is a rich source of essential oils and tannins as well as commercially available as vegetable-processed leather tanning and antiparasitic agent. This study was designed to explore the chemical composition of essential oil isolated from S. lorentzii leaves and elaborate on their significance as natural anti-diabetic, combined with molecular-docking studies. The leaf oil was chemically analysed using gas chromatography-mass spectrometry (GC-MS) method and investigated for inhibitory effects against α-amylase and α-glucosidase. Molecular-modelling study via Molecular Operating Environment-Docking (MOE-Dock) program was used to evaluate binding interactions of major components with the above-mentioned targets. The GC-MS analysis of the leaf oil revealed the predominance of β-caryophyllene (21.63±0.36%), γ-terpinene (13.53±0.74%), α-pinene (13.38±0.65%), and terpinen-4-ol (12.55±1.56%). The tested oil expressed a remarkable inhibitory effect against α-amylase with IC50 value of 2.27±0.19 μg/mL, comparable to acarbose (IC50 = 0.52±0.18 μg/mL) used as standard drug. Similarly, it significantly inhibited α-glucosidase (IC50 = 0.84±0.03 μg/mL), compared to acarbose (IC50 = 0.38±0.02μg/mL). The in-silico molecular docking study revealed favorable binding affinities of β-caryophyllene, terpinen-4-ol and sabinene with variable degrees with α-amylase and α-glucosidase. Thus, this study demonstrated valuable scientific data on the leaf oil of S. lorentzii as a potential candidate for the development of natural antidiabetic formulations.

Investigation of benzoic acid and sorbic acid concentrations in tomato paste, pepper paste, ketchup, mayonnaise, and barbeque sauce samples by headspace gas chromatography-mass spectrometry.

In this study, it was aimed at investigating benzoic acid (BA) and sorbic acid (SoA) concentrations in tomato paste, pepper paste, ketchup, mayonnaise, and barbeque sauce samples by a validated static headspace gas chromatography-mass spectrometry (GC-MS) method. Salicylic acid (SalA) was used as internal standard and the measurements were conducted in the wide linear concentration ranges of BA and SoA which were 2.5-5000 and 12.5-5000, respectively. The limit of detections (LODs) were determined to be 1.5 and 4.5 mg/kg while the limit of quantifications (LOQs) were 2.5 and 12.5 mg/kg for BA and SoA, respectively. The average recovery% values of BA and SoA were found to be 98.5% and 98.7% in an open tomato paste sample while these values were 98.7% and 100.3% in a mayonnaise sample, respectively. Accuracy of the proposed method was confirmed by statistically (significance test) evaluating excellent recovery values. In real samples, while the results of the canned tomato pastes and industrial sauce samples were found suitable, BA and SoA ​​were determined in some tomato and pepper paste products sold under the traditional or homemade name although use of the preservatives in the pastes were prohibited. It is vital for public health to prevent adulteration in pastes which is indispensable for Turkish cuisine as well as prevalently consumed in the world. Therefore, the proposed method can be used in food control laboratories due to its reliability and consumption of much less toxic chemical reagents.

Local anesthetic marcaine-bupivacaine hydrochloride and its metabolites in Forensic Samples: A case study

The local anaesthetic bupivacaine and its metabolites such as Desbutyl bupivacaine, 3-hydroxybupivacaine, and 4-hydroxybupivacaine were extracted and found in the forensic sample from postmortem samples such as cerebrospinal fluid (CSF) and postmortem blood. To separate and detect the aforesaid substances in biological matrices, high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS) and ATR-FTIR methods were used. When a couple of husband and wife who were riding on the side of road by a motor cycle which was abruptly collided by an unknown motor cycle. The couple were injured, especially in the left leg of the lady was severe pain due to bone fracture. Both were immediately admitted in nearby a Government Hospital for treatment. Anaesthetic was injected to the lady before starting the procedure of surgery. Within a few minutes she suffered pulmonary consequence and the mortality immediately occurred. Due to a therapeutic amount of bupivacaine was given, postmortem samples CSF and blood were received at forensic laboratory and extracted using a liquid-liquid extraction method (LLE). Certain chromatographic techniques and ATR-FTIR method were used to separate and detect bupivacaine and its metabolites in a forensic sample.

Establishment of a headspace-thermal desorption and gas chromatography-mass spectrometry method (HS-TD-GC-MS) for simultaneous detection of 51 volatile organic compounds in human urine: Application in occupational exposure assessment

Volatile organic compounds (VOCs) are a group of ubiquitous environment pollutants especially released into the workplace. Assessment of VOCs exposure in occupational populations is therefore a crucial issue for occupational health. However, simultaneous biomonitoring of a variety of VOCs is less studied. In this study, a simple and sensitive method was developed for the simultaneous determination of 51 prototype VOCs in urine by headspace-thermal desorption coupled to gas chromatography-mass spectrometry (HS-TD-GC-MS). The urinary sample was pretreated with only adding 0.50 g of sodium chloride to 2 mL of urine and 51 VOCs should be determined with limits of detection (LODs) between 13.6 ng/L and 24.5 ng/L. The method linearity ranged from 0.005 to 10 μg/L with correlation coefficients (r) of 0.991 to 0.999. The precision for intraday and inter-day, measured by the variation coefficient (CV) at three levels of concentration, was below 15 %, except for 4-isopropyl toluene, dichloromethane, and trichloromethane at low concentration. For medium and high levels, recoveries of all target VOCs were within the standard range, but 1,1-dichloropropene and styrene, which were slightly under 80 % at low levels. In addition, the proposed method has been used to determine urine samples collected in three times (before, during and after working) from 152 workers at four different factories. 41 types of prototype VOCs were detected in workers urine. Significant differences (Kruskal-Wallis chi-squared = 117.18, df = 1, P < 0.05) in the concentration levels of VOCs between the exposed and unexposed groups were observed, but not between the three sampling times (Kruskal-Wallis chi-squared = 3.39, df = 2, P = 0.183). The present study provides an alternative method for biomonitoring and assessing mixed exposures to VOCs in occupational populations.

Comparison of Approaches for Authentication of Commercial Terpinen-4-ol-type Tea Tree Oils Using Chiral GC/MS.

A global demand for tea tree oil (TTO) has resulted in increased adulteration in commercial products. In this study, we use a novel enantiomeric gas chromatography mass spectrometry method for chiral analysis of key terpenes ((±)-terpinen-4-ol, (±)-α-terpineol, and (±)-limonene) and quantification of components present at >0.01% to test different methods of identifying adulterated TTO. Data from authentic Australian (n = 88) and oxidized (n = 12) TTO samples of known provenance were consistent with recommended ranges in ISO 4730:2017 and previously published enantiomeric ratios, with p-cymene identified as the major marker of TTO oxidation. The 15 ISO 4730:2017 constituents comprised between 84.5 and 89.8% of the total ion chromatogram (TIC) peak area. An additional 53 peaks were detected in all samples (7.3-11.0% of TIC peak area), while an additional 43 peaks were detected in between 0 and 99% (0.15-2.0% of the TIC peak area). Analysis of nine commercial samples demonstrated that comparison to the ISO 4730:2017 standard does not always identify adulterated TTO samples. While statistical analysis of minor components in TTO did identify two commercial samples that differed from authentic TTO, the (+)-enantiomer percentages for limonene, terpinen-4-ol, and α-terpineol provided clearer evidence that these samples were adulterated. Thus, straightforward identification of unadulterated and unoxidized TTO could be based on analysis of appropriate enantiomeric ratios and quantitation of the p-cymene percentage.

Detection of Maize Mold Based on a Nanocomposite Colorimetric Sensor Array under Different Substrates.

This study developed a novel nanocomposite colorimetric sensor array (CSA) to distinguish between fresh and moldy maize. First, the headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS) method was used to analyze volatile organic compounds (VOCs) in fresh and moldy maize samples. Then, principal component analysis and orthogonal partial least-squares discriminant analysis (OPLS-DA) were used to identify 2-methylbutyric acid and undecane as key VOCs associated with moldy maize. Furthermore, colorimetric sensitive dyes modified with different nanoparticles were employed to enhance the dye properties used in the nanocomposite CSA analysis of key VOCs. This study focused on synthesizing four types of nanoparticles: polystyrene acrylic (PSA), porous silica nanospheres (PSNs), zeolitic imidazolate framework-8 (ZIF-8), and ZIF-8 after etching. Additionally, three types of substrates, qualitative filter paper, polyvinylidene fluoride film, and thin-layer chromatography silica gel, were comparatively used to fabricate nanocomposite CSA combining with linear discriminant analysis (LDA) and K-nearest neighbor (KNN) models for real sample detection. All moldy maize samples were correctly identified and prepared to characterize the properties of the CSA. Through initial testing and nanoenhancement of the chosen dyes, four nanocomposite colorimetric sensitive dyes were confirmed. The accuracy rates for LDA and KNN models in this study reached 100%. This work shows great potential for grain quality control using CSA methods.

Development of a Thermal Separation Probe Gas Chromatography–Mass Spectrometry Method for Evaluating Wax–Resin Removal by Evolon® CR

Historically, many canvas paintings were infused with wax–resin mixtures that have discolored over time, distorting the aesthetics of the work, limiting treatment options, and introducing unstable materials into the object. Removal of the wax–resin is often desirable, but before works of art can be treated, a protocol to evaluate the efficacy of the treatment must be established. A mock-up painting was infused with a known amount of a wax–resin mixture made from beeswax and dammar; this material was then extracted through six intervals of exposure to solvent-loaded and dry sheets of Evolon® CR, a non-woven textile with a high sorbent capacity. Samples from the Evolon® CR sheets from each extraction round were analyzed using thermal separation probe gas chromatography–mass spectrometry (TSP-GC/MS). Normalization of peak areas related to beeswax and dammar to those of Evolon® CR revealed the relative amount of wax and resin removed throughout the extraction. The data show that, under these test conditions, the beeswax and dammar appear to be extracted with the same relative efficiency, information that cannot be provided through UV-induced visible fluorescence imaging of the Evolon® CR sheets or weight data alone, but which is critical to capture as it has implications for treatment success and the long-term stability of an artwork.

Experimental investigation on utilization of Sesbania grandiflora residues through thermochemical conversion process for the production of value added chemicals and biofuels

All the countries in the world are now searching for renewable, environmentally friendly alternative fuels due to the shortage and environmental problems related with the usage of conventional fuels. The cultivation of cereal and noncereal crops through agricultural activities produces waste biomasses, which are being evaluated as renewable and viable fossil fuel substitutes. The thermochemical properties and thermal degradation behavior of Sesbania grandiflora residues were investigated for this work. A fluidized bed reactor was used for fast pyrolysis in order to produce pyrolysis oil, char and gas. Investigations were done to analyze the effect of operating parameters such as temperature (350–550 °C), particle size (0.5–2.0 mm), sweeping gas flow rate (1.5–2.25 m3/h). The maximum of pyrolysis oil (44.7 wt%), was obtained at 425 °C for 1.5 mm particle size at the sweep gas flow rate of 2.0 m3/h. Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry methods were used to examine the composition of the pyrolysis oil. The pyrolysis oil is rich with aliphatic, aromatic, phenolic, and some acidic chemicals. The physical characteristics of pyrolysis oil showed higher heating value of 19.76 MJ/kg. The char and gaseous components were also analyzed to find its suitability as a fuel.

Monitoring of changes in the concentration of volatile organic compound in beef irradiated with accelerated electrons

The need to develop safe methods for radiation processing of food products to improve their quality and extend their shelf life stimulates new scientific research aimed at increasing their effectiveness. Oxidation of lipids and proteins occurred under the impact of ionizing radiation in products with a high fat and water content, such as chilled meat and fish products, leads to the formation of volatile organic compounds in the product thus giving it a specific smell and taste. During storage, biochemical processes associated with microbial enzymatic activity and auto-oxidation develop in processed refrigerated products. These processes also modify the volatile organic compounds, which affect the organoleptic properties of the product. The method of gas chromatography-mass spectrometry was used to study the behavior of volatile compounds identified in irradiated beef samples both immediately after irradiation and four days later to determine the effective dose range for the radiation processing of beef. Monitoring of the content of volatile compounds in beef samples irradiated by 1-MeV electrons within a dose range from 0.25 to 5 kGy showed that the content of certain alcohols, aldehydes, and alkanes exhibited pronounced dose- and time-dependent character. The developed mathematical model describes the dependence of the concentration of volatile compounds identified immediately after irradiation in beef samples on the irradiation dose. The model is based on the simultaneous occurrence of two competing processes: the decomposition of compounds due to their oxidation and accumulation due to oxidation of other compounds after exposure to ionizing radiation. The results obtained revealed that the effective dosage range of radiation treatment lies between 250 and 1000 Gy.

Does the Quantification of Δ9-Tetrahydrocannabinolic Acid A in Serum/Plasma Provide Any Additional Information About Consumption Pattern from Drivers Under the Influence of Cannabis?

Introduction: Δ9-tetrahydrocannabinolic acid A (THCA-A) is one of the main ingredients of cannabis plants and is converted to the psychoactive substance Δ9-tetrahydrocannabinol (THC) by decarboxylation during heating above ∼90°C. During the consumption of cannabis, a varying proportion of THCA-A is absorbed into the body. Therefore, the quantification of THCA-A in serum/plasma might provide additional information on consumption behavior in driving under the influence of cannabis cases. Materials and Methods: In this study, an already established gas-chromatography mass-spectrometry (GC-MS) method for the quantification of THC, 11-OH-THC, and THC-COOH in serum and plasma samples was extended to include THCA-A. This validated method was then applied to 1228 routinely achieved serum/plasma samples from drivers suspected of cannabis consumption in Western Saxony. Two different grouping systems for chronic/occasional consumption, one system for acute/subacute consumption, Huestis formulas, and the cannabis influence factor (CIF) were used for evaluation. Results: Method validation showed appropriate results for forensic toxicological routine analysis. Limit of detection and lower limit of quantification (LLOQ) for THCA-A were 0.3 and 1.0 ng/mL, respectively. Reproducibility was <11% and accuracy ranged between 104% and 107%. THCA-A was stable in native samples at least for 2 weeks at room temperature or 4°C as well as 1 month at -20°C. Freeze-thaw stability for three cycles and processed sample stability over 3 days was proven. A total of 865 cases with a THC concentration above the German analytical cutoff of 1 ng/mL as well as the analytical LLOQs of 0.9 and 2.5 ng/mL for 11-OH-THC and THC-COOH, respectively, were included in further statistical analysis. In 407 (47.1%) of these samples, THCA-A was quantifiable. Different statistical analyses indicated a correlation between THCA-A and THC concentrations in cases of chronic and acute consumption. In addition, an increase of chronic and acute cases with increasing THCA-A concentrations was observed. However, no correlation between THCA-A and CIF was found. Discussion: These data show that THCA-A might be an additional indicative marker to provide information about consumption frequency and acuteness. Additional studies with known consumption frequencies and times are required to verify these findings.