Gas Chromatography-mass Research Articles

An integrative multi-omic analysis defines gut microbiota, mycobiota, and metabolic fingerprints in ulcerative colitis patients

BackgroundUlcerative colitis (UC) is a multifactorial chronic inflammatory bowel disease (IBD) that affects the large intestine with superficial mucosal inflammation. A dysbiotic gut microbial profile has been associated with UC. Our study aimed to characterize the UC gut bacterial, fungal, and metabolic fingerprints by omic approaches.MethodsThe 16S rRNA- and ITS2-based metataxonomics and gas chromatography–mass spectrometry/solid phase microextraction (GC–MS/SPME) metabolomic analysis were performed on stool samples of 53 UC patients and 37 healthy subjects (CTRL). Univariate and multivariate approaches were applied to separated and integrated omic data, to define microbiota, mycobiota, and metabolic signatures in UC. The interaction between gut bacteria and fungi was investigated by network analysis.ResultsIn the UC cohort, we reported the increase of Streptococcus, Bifidobacterium, Enterobacteriaceae, TM7-3, Granulicatella, Peptostreptococcus, Lactobacillus, Veillonella, Enterococcus, Peptoniphilus, Gemellaceae, and phenylethyl alcohol; and we also reported the decrease of Akkermansia; Ruminococcaceae; Ruminococcus; Gemmiger; Methanobrevibacter; Oscillospira; Coprococus; Christensenellaceae; Clavispora; Vishniacozyma; Quambalaria; hexadecane; cyclopentadecane; 5-hepten-2-ol, 6 methyl; 3-carene; caryophyllene; p-Cresol; 2-butenal; indole, 3-methyl-; 6-methyl-3,5-heptadiene-2-one; 5-octadecene; and 5-hepten-2-one, 6 methyl. The integration of the multi-omic data confirmed the presence of a distinctive bacterial, fungal, and metabolic fingerprint in UC gut microbiota. Moreover, the network analysis highlighted bacterial and fungal synergistic and/or divergent interkingdom interactions.ConclusionIn this study, we identified intestinal bacterial, fungal, and metabolic UC-associated biomarkers. Furthermore, evidence on the relationships between bacterial and fungal ecosystems provides a comprehensive perspective on intestinal dysbiosis and ecological interactions between microorganisms in the framework of UC.

Characterization and correlations of dominant microorganisms and volatile compounds in fermentation process of Yangjiang douchi.

Yangjiang douchi (YD) is a traditional fermented soybean product, which is popular in Chinese cuisine for its unique flavor. However, due to its high salt content and unstable flavor, its competitiveness in the international market is gradually weakening. Microorganisms have a key role in the production process of YD because it is a fermented food but the effect of microorganisms on the volatile compounds of YD is also not currently clear. In this paper, aroma compounds and microbial diversity in different fermentation stages of YD were analyzed using gas chromatography-mass spectrometry/olfactometry (GC-MS/O) and IlluminaMiseq system sequencing. A total of 78 aroma-active compounds were detected throughout the fermentation process and they influenced the formation of flavor in YD. Fungi flora were relatively single in YD, and bacteria were rich and varied. A total of 418 species of bacteria were present during fermentation, with unclassified_Staphylococcus, Staphylococcus_kloosii, and Bacillus_velezensis_Bacillus predominating. There were 25 species of fungi at the species level, and Aspergillus minisclerotigenes (OTU 4) played a dominant role in the whole fermentation process. Staphylococcus and Bacillus in the bacterial genus were strongly correlated with most flavor compounds detected, and A. minisclerotigenes in the fungi were more relevant to flavor compounds. This research provides a theoretical basis for the enhancement of the flavor of traditional fermented douchi in China. © 2024 Society of Chemical Industry.

In Vivo and In Vitro Metabolic Fate and Urinary Detectability of Five Deschloroketamine Derivatives Studied by Means of Hyphenated Mass Spectrometry

Ketamine derivatives such as deschloroketamine and deschloro-N-ethyl-ketamine show dissociative and psychoactive properties and their abuse as new psychoactive substances (NPSs) has been reported. Though some information is available on the biotransformation of dissociative NPSs, data on deschloro-N-cyclopropyl-ketamine deschloro-N-isopropyl-ketamine and deschloro-N-propyl-ketamine concerning their biotransformation and, thus, urinary detectability are not available. The aims of the presented work were to study the in vivo phase I and II metabolism; in vitro phase I metabolism, using pooled human liver microsomes (pHLMs); and detectability, within a standard urine screening approach (SUSA), of five deschloroketamine derivatives. Metabolism studies were conducted by collecting urine samples from male Wistar rats over a period of 24 h after their administration at 2 mg/kg body weight. The samples were analyzed using liquid chromatography high-resolution tandem mass spectrometry (LC-HRMS/MS) and gas chromatography–mass spectrometry (GC-MS). The compounds were mainly metabolized by N-dealkylation, hydroxylation, multiple oxidations, and combinations of these metabolic reactions, as well as glucuronidation and N-acetylation. In total, 29 phase I and 10 phase II metabolites were detected. For the LC-HRMS/MS SUSA, compound-specific metabolites were identified, and suitable screening targets could be recommended and confirmed in pHLMs for all derivatives except for deschloro-N-cyclopropyl-ketamine. Using the GC-MS-based SUSA approach, only non-specific acetylated N-dealkylation metabolites could be detected.

Optimum Condition for the Formation of β-ionone by Thermal Decomposition of Carotenoids Extract from Orange Sweet Potato (Ipomoea Batatas L.)

Introduction The need for rose aromatic compounds is very high globally, where the beta-ionone compound as a precursor for rose aroma can be produced through the oxidation process of carotenoids, especially beta carotene. Therefore, Beta-ionone is the compound responsible for the rose fragrance, which is needed industrially. Carotenoids are easily degraded by various factors, namely heat, oxygen, light and enzymatic. This research has carried out heat degradation of carotene compounds extracted from orange sweet potato to determine the effect of heating time on forming aromatic compounds such as Beta-ionone and dihydroactinidiolide (dhA). Methodology Thermal degradation of carotene was carried out at 140°C for 1, 2, 3, and 4 h. The constant oxygen concentration of 7 l.h-1 was used to induce the oxidation. The spectrophotometric analysis of total carotene and the gas chromatographic-mass spectrometry analysis of volatile compounds were conducted to clarify the efficiency of the carotene degradation process and aromatic compounds' formation, respectively. Results Orange sweet potatoes contain 1.2% of carotenoids on a dry weight basis. Beta-ionone and dihydroactinidiolide compounds increased along with decreased total carotene value during heating. The results showed that heating sweet potato carotene at 140°C for 4 h caused carotene degradation of up to 93%. Therefore, the optimum thermal degradation treatment for the formation of β-ionone and dhA compounds was the heating condition at a temperature of 140°C for 4 h. Conclusion This research has shown the potential of sweet potatoes as a non-aromatic raw material that can be used to produce aromatic compounds. The use of the crude extract in this research means that the beta-ionone content in the product after oxidation is still low due to the presence of other components; this needs to be a concern for further research.

Prevalence of Psychoactive Substance Use During Pregnancy in Argentine Women: A Pilot Study Testing Maternal Hair

Background: The use of psychoactive substances (PSs) during pregnancy is a major public health concern because of their increasing prevalence worldwide. This study examined the understudied issue of gestational PS consumption in a cohort of Argentine delivering mothers. Methods: A cross-sectional pilot study involving 51 women receiving delivery care was conducted at the Santa Rosa Hospital in La Pampa, Argentina. Information on maternal sociodemographic characteristics, pregnancy history, and drug use was obtained through standardized interviews. Maternal hair samples were analyzed for alcohol, tobacco, licit, illicit, and prescription substance biomarkers using ultra-high-performance liquid chromatography high-resolution mass spectrometry and gas chromatography mass spectrometry. Results: During pregnancy, 49.0% of participants reported alcohol consumption, 25.5% reported tobacco use, and 23.5% reported cannabis use. Hair samples from 56.9% of the women were positive for illicit PSs, with the most frequent being cocaine (41.2%) and cannabis (15.7%). Among the women, 47.1% consumed alcohol during pregnancy. Of the 24 women with hair ethyl glucuronide ≥5 pg/mg, 33.3% drank until the end of gestation and 58.3% started a social drinking habit in the second half. The analysis also detected prescription substances (anticonvulsants, antidepressants, methadone, opioids, antihistamines, antiemetics, and analgesics), caffeine (70.6%), lidocaine, and levamisole, some of which were cocaine or opioid adulterants. Conclusions: This is the first study to objectively assess the consumption of licit and illicit PSs during pregnancy in Argentina. In contrast to most nearby countries, cocaine was the most detected illicit PS in this cohort of Argentine delivering women. This finding highlights the importance of regular monitoring of local trends in PS use during pregnancy.

A quantitative investigation on pyrolysis behaviors of metal ion-exchanged coal macerals by interpretable machine learning algorithms

Generalizing the rules from complex processes such as catalytic pyrolysis to guide their process control is always a difficult but attractive task. The influences of ion-exchange of metal ions (Na+, K+, Ca2+, Mg2+, Co2+ and Ni2+) on the pyrolysis behavior of vitrinite and inertinite from Shendong coal were investigated by thermogravimetric analyzer-Fourier transform infrared spectrometer (TG-FTIR), fixed-bed reactor (FBR), gas chromatograph-mass spectrometer (GC-MS) and X-ray diffractometer (XRD). A set of machine learning models was successfully constructed based on random forest, support vector machine, and Gaussian process regression, to quantify the relationships between pyrolysis behaviors and the properties of metals and macerals. The leave-one-out-cross validation showed that there are considerable determination coefficients (R2 > 0.9) between predicted and experimental values for most responses (17 out of 29). By combining genetic programming-based symbolic regression with the black-box algorithm, 23 symbolic regression expressions with high confidence were successfully constructed. This work is a pioneering attempt of optimization in small-scale experiments. By utilizing the highly interpretable models, a demand-orientated (multi-)optimization coal pyrolysis can be achieved. The bi-objective optimization was conducted on the yield of tar and the content of light aromatics in tar, and the results show that Co is the optimal loading metal.

Revisit the benzene oxidation at elevated pressure

The benzene (A1) oxidation was examined in a jet-stirred reactor (JSR) within the temperature range of 880–1010 K at 12.0 atm under both fuel lean (Φ = 0.5) and rich (Φ = 3.0) conditions. Eighteen intermediates and products were identified and quantified by gas chromatography (GC) and gas chromatograph-mass spectrometer (GC–MS). A kinetic model comprising 280 species and 1734 reactions was developed and validated against the experimental data to investigate the benzene reactions occurring at high pressure and low temperature. According to the sensitivity analysis, A1 + OH = A1- + H2O is the most promoting reaction for fuel consumption, while A1OH + O2 = A1O + HO2 and A1OH + OH = A1O + H2O exhibited the most inhibiting effects. HO2 radicals play an important role in the initial reaction temperature of A1 high-pressure oxidation, where the reaction rate of A1OH + O2 = A1O + HO2 is particularly critical. In comparison to previous works on A1 oxidation, oxygenated polycyclic aromatic hydrocarbons (OPAHs) benzofuran (C8H6O) and dibenzofuran (C12H8O) were newly measured and analyzed in this work. As one of the most important OPAHs species, the consumption pathway of C8H6O was updated to better describe the high-pressure oxidation. The C8H6O would potentially compete with A1 for molecular oxygen via the pathway A1 → A1O → C8H6O → decomposition products, and the process of decomposition enhances the oxygen depletion. Compared with previous oxidation studies at atmospheric pressure, the A1 initial reaction temperature shifted from 1000 to 950 K, and the temperature window of fuel conversion sharply reduced from 300 K to 70 K. Additionally, the model was effectively applied to predict the oxidation of A1 in a Jet-Stirred Reactor (JSR) over a wide range of pressures, from 0.46 to 12.0 atm. Furthermore, the developed model was compared with the laminar flame velocities (LBVs, ranging from 1.0 - 10.0 atm) and the ignition delay times (IDTs, ranging from 2.4 – 9.0 atm) data in the literature, and satisfactory agreement was obtained across a broad pressure range. The newly reported data and kinetic model provide helpful in further understanding the combustion mechanisms of aromatic hydrocarbon fuels.

Optimal Extraction Technique and Antibacterial Properties of Essential Oil Through Magnolia sieboldii K. Koch Leaves

To provide scientific support for the exploration and application of the essential oil derived through leaves of Magnolia sieboldii K. Koch, this paper explores extraction technology optimization, composition analysis, and antibacterial properties for the essential oil derived through Magnolia sieboldii K. Koch leaves. Essential oil derived through Magnolia sieboldii K. Koch leaves was extracted by adopting hydrodistillation. With single-factor test and reaction surface improvement methods, the extraction technology of essential oil derived through Magnolia sieboldii K. Koch leaves was optimized. The structure of chemicals has been explored through the use of gas chromatographmass spectrometer (GC-MS) technology. By conducting Kirby-Bauer test and applying spread plate method, the antibacterial properties for essential oil has been measured. The liquid-solid ratio was 7.15 mL/g, the dilution period was 4.00 h, and the NaCl mass percentage was 2.26% as a consequence of the response surface optimization. The rate about gathered essential oil under such circumstances was 0.31537%. By performing chemical composition analysis, 43 compounds were measured from essential oil. Thel oil was sensitive to Staphylococcus aureus, Bacillus subtilis, and Escherichia coli with inhibitory area diameters of 17.27, 10.85, and 9.56 mm, respectively. The minimum inhibitory concentration (MIC) values for the three bacteria strains were 2.5 × 10–6, 5 × 10–6, and 10 × 10–6 g/mL, respectively. The optimum extraction rate of essential oil derived through leaves of Magnolia sieboldii K. Koch by hydro distillation is 0.35%, with the cancer-fighting substance β-elemene reaching up to a maximum of 42.53%. Simultaneously, the essential oil derived through leaves of Magnolia sieboldii K. Koch exhibits notable antibacterial effect and large development potential, suggesting the comprehensive development and utilization.

Metabolomic analysis reveals the changing trend and differential markers of volatile and nonvolatile components of Artemisiae argyi with different aging years.

Artemisia argyi Folium (AAF) is a traditional medicinal herb and edible plant. Analyzing the differential metabolites that affect the efficacy of AAF with different aging years is necessary. The aim of the study was to investigate the changing trend and differential markers of volatile and nonvolatile metabolites of AAF from different aging years, which are necessary for application in clinical medicine. Metabolites were analyzed using a widely targeted metabolomic approach based on ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and gas chromatography tandem mass spectrometry (GC-MS). A total of 153 volatile metabolites and 159 nonvolatile metabolites were identified. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) could clearly distinguish AAF aged for 1 year (AF-1), 3 years (AF-3), and 5 years (AF-5). Seven flavonoids and nine terpenoids were identified as biomarkers for tracking the aging years. The metabolomic method provided an effective strategy for tracking and identifying biomarkers of AAF from different aging years. This study laid the foundation for analysis of the biological activity of Artemisia argyi with different aging years.

AhR agonists screening and identification in indoor dust based on non-target chemical analysis by GC-Q-TOFMS and biological effect evaluation referring to ToxCast/Tox21 database

Numerous studies reported the concentration of agonists of aryl hydrocarbon receptor (AhR) in indoor dust by target chemical analysis or the biological effects of activating the AhR by indoor extracts, but the major AhR agonists identification in indoor dust were rarely researched. In the present study, the indoor dust samples were collected for 7-ethoxyresorufin O-deethylase (EROD) assay and both non-targeted and targeted chemical analysis for AhR agonists by gas chromatography quadrupole time-of-flight mass spectrometry and gas chromatography–mass spectrometry analysis. Coupled with non-targeted analysis and toxicity Forecaster (ToxCast)/Tox21 database, 104 ToxCast chemicals were screened to be able to induce EROD response. The combination of targeted chemical analyses and biological effects evaluation indicated that PAHs, dibutyl phthalate (DBP) and Cypermethrin might be the important AhR-agonists in different indoor dust and mainly contributed in 1.84%–97.56 % (median: 26.62%) of total observed biological effects through comparing toxic equivalency quotient derived from chemical analysis with biological equivalences derived from bioassay. DBP and cypermethrin seldom reported in the analysis of AhR agonists should raise great concern. In addition, the present results in experiment of synthetic solution of 4 selected AhR-agonists pointed out that some unidentified AhR agonists existed in indoor dust.

Characterization of odor-active compounds in Liuzhou River snail rice noodles soup by sensory-directed flavor analysis

Liuzhou River snails rice noodles, a special snack of Liuzhou City in the Guangxi Zhuang Autonomous Region, China, possess a unique flavor of spicy, refreshing, fresh, sour, and hot. The present study aimed to characterize the composition of volatile compounds and key odor-active compounds in river snails rice noodles soup (RSRNS) through aroma extract dilution analysis and odor activity value calculation using solid-phase microextraction (SPME) combined with comprehensive two-dimensional gas chromatography–olfactometry–mass spectrometry (GC×GC–O–MS) and gas chromatography–olfactometry–mass spectrometry (GC–O–MS). A total of 71 volatile compounds were identified by GC–O–MS, of which 49 were odor-active. Meanwhile, 125 volatile compounds were identified by GC×GC–O–MS, of which 68 were odor-active. These results indicated that 3-methylbutanal, linalool, 1,8-cineole, myrcene, 2-acetylpyrazine, 4-allylanisole, 2-acetylthiazole, 1-octen-3-ol, hexanal, and eugenol were the main odor-active compounds of RSRNS.

Characterization and optimization of exopolysaccharide extracted from a newly isolated halotolerant cyanobacterium, Acaryochloris Al-Azhar MNE ON864448.1 with antiviral activity

Several antiviral agents lost their efficacy due to their severe side effects and virus mutations. This study aimed to identify and optimize the conditions for exopolysaccharide (EPS) production from a newly isolated cyanobacterium, Acaryochloris Al-Azhar MNE ON864448.1, besides exploring its antiviral activity. The cyanobacterial EPS was purified through DEAE-52 cellulose column with a final yield of 83.75%. Different analysis instruments were applied for EPS identification, including Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), and gas chromatographic-mass spectrometry (GC–MS). Plackett–Burman’s design demonstrated that working volume (X1), EDTA (X2), inoculum size (X3), CaCl2 (X4), and NaCl (X5) are the most important variables influencing EPS production. Central composite design (CCD) exhibited maximum EPS yield (9.27 mg/mL) at a working volume of 300 mL in a 1 L volumetric flask, EDTA 0.002 g/L, inoculum size 7%, CaCl2 0.046 g/L, and NaCl 20 g/L were applied. EPS showed potent antiviral activities at different stages of herpes simplex virus type-1 and 2 (HSV-1, HSV-2), adenovirus (ADV) and coxsackievirus (A16) infections. The highest half-maximal inhibitory concentration (IC50) (6.477 µg/mL) was recorded during HSV-1 internalization mechanism, while the lowest IC50 (0.005669 µg/mL) was recorded during coxsackievirus neutralization mechanism.

“GC-MS profiling, sub-acute toxicity study and total phenolic and flavonoid content analysis of methanolic leaf extract of Schima wallichii (D.C.) Korth-a traditional antidiabetic medicinal plant”

Ethnopharmacological relevanceSchima wallichii (D.C.) Korth is traditionally used in Manipur, India for treatment of diabetes and hypertension. However, there is no data reported regarding safety profile of this medicinal plant upon repeated per oral administration over a period of time. Aim of the studyIn the current study phytochemical profile, toxicological profile and total phenolic and flavonoid compound content of Schima wallichii leaves extract were evaluated. Materials and methodsGas chromatography coupled to mass spectrometry was performed for chemical profiling by using Gas Chromatography-Mass Spectrometry/Mass Spectrometry (GC-MS/MS), Shimadzu, TQ8040 system. A 28 days sub-acute toxicity study was carried out using albino Wistar rats by administering 3 different doses (200, 400 and 800 mg/kg body weight per oral) of methanol leaves extract. Changes in body weights were recorded weekly. Serum biochemical parameters were estimated as well as blood-cell count was done to check the effect of extract on haematopoietic system. Histopathology of vital organs viz. kidney, heart, brain, liver was performed to find any pathological indications. Since, liver is main the site for xenobiotic metabolism, estimation of the level of glutathione, catalase and lipid peroxidation were done. Further, total phenolic and flavonoid compound content estimation was performed for the leaves extract. ResultsGC-MS revealed 14 major compounds with area percentage >1% of which quinic acid, n-Hexadecanoic acid, 9,12,15-Octadecatrienoic acid, (Z,Z,Z)-, Octatriacontyl trifluoroacetate, are three major compounds. No mortality was observed after the treatment with extract. Blood-cell count and biochemical parameters didn't show significant deviation as compared to control group. Histopathology study of vital organs viz. (liver, kidney, heart and brain) showed normal cellular construction comparing to control group. There was no sign of membrane lipid peroxidation, depletion of catalase level and glutathione level in liver. The result demonstrates that NOAEL (no-observed-adverse-effect levels) in the sub-acute toxicity was above 800 mg/kg. The leaves extract showed significant total phenol and flavonoid content. ConclusionThe present study revealed that Schima wallichii possessed important bioactive compounds with therapeutic values. The plant was safe for consumption after repeated high doses administration in rats and possesses significant amount of total phenol and flavonoid content.

A new sustainable filtration membrane extraction method based on nanoconfined liquid phase extraction: Determination of organochlorinated pesticides and pyrethroids in tea samples

BackgroundPesticides are used in agricultural production for prevent and control crop diseases and pests, but it is easy to cause excessive pesticides residues in agricultural products, polluting the environment and endangering human health. Due to their unmatched and sustainable capabilities, nanoextraction procedures are becoming every day more important in Analytical Chemistry. In particular, nanoconfined liquid phase extraction has shown extraction capabilities toward polar, medium polar, and/or nonpolar substances, which can be easily modulated depending on the nanoconfined solvent used. Furthermore, this “green” technique showed excellent characteristics in terms of recoveries, extraction time (≤1 min), reliability, and versatility. (97) ResultsIn this work, the advantages of this technique have been coupled with those of filtration membrane extraction, making use of carbon nanofibers (CnFs) growth on carbon microspheres (CμS). This substrate has been deposited on a filter, which combined with gas chromatographic mass spectrometry (GC-MS) analysis successfully employed for the nanoextraction of 30 pesticides (18 organochlorine and 12 pyrethroids) in tea samples. Under the optimized extraction conditions, the linear range with standard solutions was from 1 to 1000 ng mL−1 (R2 ≥ 0.99), the limit of detections in tea samples were in the range 0.56–17.98 μg kg−1. The accuracy of the developed method was evaluated by measuring the extraction recovery of the spiked tea samples, and recoveries between 74.41 % and 115.46 %. (119) SignificanceConsidering the versatility of nanoconfined liquid phase extraction and the functionality of the filtration membrane extraction procedure, this new extraction method can be considered a powerful candidate for automatized high-throughput analyses of real samples. (34)

Elucidating salt-reduction mechanisms of aroma-active compounds from yeast extracts through sensomics approaches and electroencephalography

This study investigated the savory intensity of aroma-active compounds derived from yeast extract Maillard reaction models. Sensory evaluation results revealed that beef flavoring model (28.00 g) exhibited the highest savory perception intensity when the yeast extract FA34 (0.50 g) the added. Eleven aroma-active compounds associated with saltiness perception were identified via solid-phase microextraction and extraction combined with gas chromatography–mass spectrometry/olfactory. The odorant–NaCl mixture model and saltiness intensity evaluation results revealed that thiazole and 4-methylpentanoic acid could significantly (p < 0.05) enhance the saltiness perception of salt solution (5.00 g/L), 2-methylpyrazine, 2-methyl-3-furanthiol, 2,6-dimethylpyrazine, furfuryl mercaptan, and methyl 2-methyl-3-furyl disulfide could significantly (p < 0.01) enhance the saltiness perception of a salt solution (5.00 g/L). Electroencephalography revealed that the main mechanisms underlying aroma-induced saltiness perception enhancement included the strengthening of the saltiness perception signal and prolonging signal stimulation time in the frontal regions of the cerebral cortex.

Gas chromatography–mass spectrometry‐based electronic nose, glycosidically bound volatile, and alcohol‐acyltransferase activity profiles of Okinawan pineapple

Gas chromatography–mass spectrometry‐based electronic nose, glycosidically bound volatile, and alcohol‐acyltransferase activity profiles of Okinawan pineapple

The organic geochemistry of crude oil in the Saltpond Basin (Ghana): Organic source input, depositional environment, and thermal maturity

The Saltpond Basin, situated within the South Atlantic margin of Ghana, is a significant area for petroleum exploration but has received relatively limited research attention. Previous studies have examined source rock composition, but data on crude oil organic chemistry are lacking, hindering understanding of the basin’s petroleum system and evolution. To address this gap, we analyzed biomarkers and stable carbon-isotope ratios in Saltpond Basin crude oil using gas chromatography–mass spectrometry and gas chromatography–isotope ratio mass spectrometry to elucidate organic matter source, depositional environment, and thermal maturity. Findings were compared with oils from the West African segment of the South Atlantic margin, namely the Tano Basin and the Niger Delta Basin, to identify potential correlations and gain insights into regional variations. Molecular and isotopic results unveiled a significant prevalence of organic matter derived from lower marine organisms. Patterns of organic matter deposition and preservation in Saltpond oil samples suggested a suboxic marine transitional environment, contradicting conventional understanding of terrestrial dominance in such settings. Moreover, the potential for degradation processes to obscure differentiation between terrestrial and marine organic matter origins underscores the complex nature of organic matter dynamics in transitional marine environments. Analysis of molecular thermal maturity indices suggested Saltpond oils were expelled from source rocks exhibiting thermal maturity at the early maturity stage. Correlation analysis unveiled genetic disparities among crude oils sourced from the Saltpond Basin and those from the Tano and Niger Delta Basin, primarily due to variations in source input and depositional environment conditions. Saltpond oil exhibits lower terrestrial organic input than Tano Basin’s crude oils, which also have less terrestrial input than Niger Delta Basin crude oils. Additionally, its paleodepositional environment notably differs from oils in the Tano Basin (anoxic transitional marine-lacustrine settings) and the Niger Delta Basin (suboxic–oxic terrigenous deltaic or marine or lacustrine environments). Thermal maturity range of Saltpond oil is comparable to oils in the Tano Basin but lower than oils in the Niger Delta Basin. These findings provide valuable insights into petroleum generation history and unique organic geochemical characteristics within the Saltpond Basin, essential for exploration, production, and environmental management efforts in the region. Furthermore, correlation studies provide evidence that distinct biological, geological, and paleoenvironmental conditions shaped various oil types in the West African segment of the South Atlantic margin.

Functional types of long trichoid sensilla responding to sex pheromone components in Plutella xylostella.

Sex pheromones, which consist of multiple components in specific ratios promote intraspecific sexual communications of insects. Plutella xylostella (L.) is a worldwide pest of cruciferous vegetables, the mating behavior of which is highly dependent on its olfactory system. Long trichoid sensilla on male antennae are the main olfactory sensilla that can sense sex pheromones. However, the underlying mechanisms remain unclear. In this study, 3 sex pheromone components from sex pheromone gland secretions of P. xylostella female adults were identified as Z11-16:Ald, Z11-16:Ac, and Z11-16:OH in a ratio of 9.4 : 100 : 17 using gas chromatography - mass spectrometry and gas chromatography with electroantennographic detection. Electrophysiological responses of 581 and 385 long trichoid sensilla of male adults and female adults, respectively, to the 3 components were measured by single sensillum recording. Hierarchical clustering analysis showed that the long trichoid sensilla were of 6 different types. In the male antennae, 52.32%, 5.51%, and 1.89% of the sensilla responded to Z11-16:Ald, Z11-16:Ac, and Z11-16:OH, which are named as A type, B type, and C type sensilla, respectively; 2.93% named as D type sensilla responded to both Z11-16:Ald and Z11-16:Ac, and 0.34% named as E type sensilla were sensitive to both Z11-16:Ald and Z11-16:OH. In the female antennae, only 7.53% of long trichoid sensilla responded to the sex pheromone components, A type sensilla were 3.64%, B type and C type sensilla were both 0.52%, D type sensilla were 1.30%, and 1.56% of the sensilla responded to all 3 components, which were named as F type sensilla. The responding long trichoid sensilla were located from the base to the terminal of the male antennae and from the base to the middle of the female antennae. The pheromone mixture (Z11-16:Ald : Z11-16:Ac : Z11-16:OH=9.4 : 100 : 17) had a weakly repellent effect on female adults of P. xylostella. Our results lay the foundation for further studies on sex pheromone communications in P. xylostella.

Evaluation of chemical components and quality in Xinhui Chenpi (Citrus reticulata ‘Chachi’) with two different storage times by GC–MS and UPLC

AbstractXinhui Chenpi (XHCP) is a well‐known type of Chenpi (CP) widely used as both a Chinese herb and a food ingredient. While previous studies have explored how the quality of CP changes over time, there has been limited research specifically on XHCP. This study aims to assess the chemical components and quality of XHCP based on total flavonoid content (TF), antioxidant activity (AA), and color value (CV) at two stages: freshly harvested (XHCP‐0Y) and after 3 years of storage (XHCP‐3Y). Thirty‐eight common volatile compounds were identified, and the content of 17 compounds among them, nine nonvolatile compounds, which included one alkaloid (synephrine), three phenolic acids (PA, protocatechuic acid, vanillic acid, and ferulic acid), and five flavonoids (narirutin, hesperidin, sinensetin, nobiletin, and tangeretin), were firstly detected by the newly developed gas chromatograph–mass spectrometer (GC–MS) and ultra‐performance liquid chromatography (UPLC) methods. Compared to XHCP‐0Y, the content of 17 volatile compounds and synephrine decreased in XHCP‐3Y to varying degrees, while the content of PA, five flavonoids, TF, AA, and CV increased. The reduction of dryness caused by volatile compounds and the enhancement of efficacy related to PA, flavonoids, and AA suggested improved quality of XHCP after 3 years of storage. The methods developed in this study show promise for evaluating the quality of XHCP during the aging process.

Method validation, dissipation and risk ranking of multi-pesticides in blueberry

Blueberry production and consumption are gradually increasing in China; however, the potential risks of pesticide residues are essentially unknown. In this study, a modified QuEChERS method was used for the analysis of twenty pesticides and their nine metabolites in blueberry by ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) and gas chromatography with tandem mass spectrometry (GC-MS/MS). This method achieved high linearity (R2 > 0.99), accuracy (average recovery, 70–125%), precision (relative standard deviation, RSD ≤12%), and sensitivity (limit of quantification, LOQ, 0.01 mg/kg). The dissipation of most pesticides fitted the first-order model, and the half-lives were in the range of 2.21–35.65 d. The residual levels of the analytes on the first day after application were below maximum residue limits (MRLs) on fruits, and ten pesticides with MRLs in China were categorized as low-risk pesticides according to the risk ranking. This study provides a reference for the rational application of pesticides for blueberry cultivation.