Deciphering the Potential Therapeutic Effects of Hydnocarpus wightianus Seed Extracts using in vitro and in silico approaches.

Phytocompounds possess the potential to treat a broad spectrum of disorders due to their remarkable bioactivity. Naturally occurring compounds possess lower toxicity profiles, which making them attractive targets for drug development. Hydnocarpus wightianus seeds were extracted using ethanol, acetone, and hexane solvents. The extracts were evaluated for phytochemicals screening and other therapeutic characteristics, such as free radicals scavenging, anti α-amylase, anti α-glucosidase, and anti-bacterial activities. The ethanolic extract exhibited noteworthy antibacterial characteristics and demonstrated considerable antioxidant, and anti-diabetic effects. The IC50 value of the ethanolic extract for Dpph, α-amylase, and α-glucosidase were found to be 77.299 ± 3.381 µg/mL, 165.56 2.56 µg/mL, and 136.58 ± 5.82 µg/mL, respectively. The ethanolic extract was effective against Methicillin resistant Staphylococcus aureus (26 mm zone of inhibition at 100 µL concentration). Molecular docking investigations revealed the phytoconstituent's inhibitory mechanisms against diabetic, free radicals, and bacterial activity. Docking score for phytocompounds against targeted protein varies from -7.2 to -5.1 kcal/mol. The bioactive compounds present in the ethanolic extract were identified by Gas chromatography/Mass spectrometry analysis, followed by molecular docking and molecular dynamic simulation studies to further explore the phytoconstituent's inhibitory mechanism of α-glucosidase, ∝-amylase, radical scavenging, and bacterial activity. The electronic structure and possible pharmacological actions of the phytocompound were revealed through the use of Density Functional Theory (DFT) analysis. Computational and in vitro studies revealed that these identified compounds have anti-diabetic, anti-oxidant, and anti-bacterial activities against antibiotic-resistant strain of Staphylococcus aureus.

Profiling the volatile compounds of Peganum harmala L. Based on multiple sample preparation coupled with gas chromatography-mass spectrometry analysis and explored its antidepressants-like activity.

Peganum harmala L., a traditional medicinal plant in China, is renowned for its significant alkaloid content in seeds and roots exhibiting a wide range of pharmacological activities, including antidepressant, antiseptic, and antiviral. However, the volatile composition of the herb remained unclear. Apart from that, the extraction of volatile compounds through essential oil presents challenges due to the low yield and the degradation of volatile active compounds at high temperatures. This study used multiple sample preparation methods including headspace (HS), needle trap device (NTD), and liquid-liquid extraction (LLE) coupled with gas chromatography-mass spectrometry (GC-MS) to analyze the volatile compounds from the areal part of P. harmala L.. A total of 93 compounds were identified with NTD facilitating the first detection of harmine among the volatile organic compounds. Through network pharmacology and protein interaction analysis, the compounds' potential therapeutic targets of the compounds were explored, and 23 key targets were obtained (AKT1, ALB, PTGS2, MAOA, etc). KEGG pathway enrichment analysis indicated significant involvement in neuroactive ligand-receptor interactions and serotonergic synapses. The results enhanced the understanding of P. harmala's pharmacological mechanisms and supported its ethnopharmacological use.

The chemical composition and the preservative, antimicrobial, and antioxidant effects of Thymus broussonetii Boiss. essential oil: an in vitro and in silico approach.

Introduction: The aim of this study was to evaluate the antioxidant, antimicrobial, and preservative efficacy of Thymus broussonetii Boiss. essential oil (EO) in a topically applied formulation using a challenge test. Methods: The essential oil was extracted from the aerial part of T. broussonetii using hydrodistillation, and the obtained EO was further analyzed by gas chromatography/mass spectrometry (GC/MS). The antioxidant effect of the EO was evaluated using three methods: the inhibition of free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH), ß-carotene-linoleic acid, and the ferric reducing antioxidant power (FRAP) methods. The antimicrobial activity and the minimum inhibitory concentration (MIC) of this EO were assayed by the disk-diffusion method and the broth microdilution method, respectively. The preservative efficacy of T. broussonetii EO was assayed at 1% and 2% (v/w) in a topical cream formulation using a challenge test against standard-specific microorganisms recommended by the European Pharmacopoeia. Furthermore, the identified phytochemical compounds were docked for their effect on nicotinamide adenine dinucleotide phosphate oxidase, human casein kinase 1 alpha 1 (CSNK1A1), glycogen synthase kinase 3, Staphylococcus aureus nucleoside diphosphate kinase, Escherichia coli beta-ketoacyl-[acyl-carrier protein] synthase, Pseudomonas aeruginosa LasR ligand-binding domain, and sterol 14-alpha demethylase (CYP51) from Candida albicans. The ADME/toxicity was predicted by analyzing the absorption, distribution, metabolism, and excretion parameters. Results and discussion: chemical composition of the EO revealed the presence of thymol (63.09%), p-cymene (11%), and γ-terpinene (8.99%) as the major components. The antioxidant assays revealed that the essential oil exhibited strong antioxidant activity, as indicated by the minimum inhibitory concentration IC50 (IC50 = 210 ± 0.3 µg/mL for the DPPH assay, IC50 = 145 ± 0.1 µg/mL for the ß-carotene assay, and IC50 = 84 ± 0.21 µg/mL for the FRAP assay) when compared to quercetin and butylated hydroxytoluene (BHT) as controls. The investigated essential oil exhibited important antimicrobial activity against all the tested microorganisms, and the MICs of the EO against bacteria and fungi were 0.02%-1%. Moreover, the EO of T. broussonetii evaluated at 2% (v/w) in a cream formulation succeeded in satisfying the A criteria for preservation efficacy against S. aureus, E. coli, and Aspergillus brasiliensis but exhibited less efficacy against P. aeruginosa (1.78 log reduction in the number of CFU/g after 7 days of evaluation) and C. albicans (1.09 log reduction in the number of CFU/g after 14 days of evaluation) when compared to the synthetic preservative phenoxyethanol 1% (v/w). In silico results showed that the antimicrobial activity of T. broussonetii EO is mostly attributed to thymol, terpinen-4-ol, and aromadendrene, while the antioxidant activity is attributed to thymol. These results indicate that the EO of T. broussonetii possesses important antimicrobial and antioxidant properties and can, therefore, be used as a natural preservative ingredient in the cosmetic industry.

Analysis of chlordecone and its transformation products in environmental waters by a new SPME-GC-MS method and comparison with LLE-GC-MS/MS and LLE-LC-MS/MS: A case study in the French West Indies.

Among the numerous organochlorines (OCs) applied in the French West Indies (FWI), chlordecone (hydrated form C10Cl10O2H2; CLD) still causes major environmental pollution nowadays. A recent report revealed the unexpected presence in FWI environment of transformation products (TPs) of CLD not routinely monitored due to a lack of commercial standards. Here, we present a method for surface waters and groundwaters to analyze CLD, its main TPs (hydroCLDs, chlordecol (CLDOH), 10-monohydroCLDOH and polychloroindenes) and other OCs. We developed an SPME-GC-SIM/MS method with a PDMS-DVB fiber. Since CLDOH-d commonly used as internal standard (IS) proved unsuitable, we synthesized several IS candidates, and finally identified 10-monohydro-5-methyl-chlordecol as a satisfactory IS for CLDOH and 10-monohydroCLDOH avoiding the use of 13C-labelled analogue. LODs for CLD and its TPs varied from 0.3 to 10 ng/L, equal to or below LODs of the two laboratories, BRGM (the French geological survey) and LDA26 (one of the French Departmental Analytical Laboratories), requested in FWI pollution monitoring that used liquid-liquid extractions and advanced facilities (LLE-GC-MS/MS and LLE-LC-MS/MS methods, respectively). Then, we extended the multi-residue method to 30 OCs (CLD and its TPs, mirex, ß-HCH, lindane, dieldrin, aldrin, HCB, hexachlorobutadiene, TCE, PCE) and applied it to 30 surface and ground waters from FWI. While CLD, 8- and 10-monohydroCLD, CLDOH, 10-monohydroCLDOH, dieldrin, and ß-HCH were detected and quantified, pentachloroindene, another CLD TP, was sporadically found in trace levels. A comparison with BRGM and LDA26 confirmed the interest of the SPME method. Results suggested an underestimation of CLDOH and an overestimation of high CLD concentrations with one of the currently used routine protocol. In light of these findings, previous temporal monitoring of environmental waters in FWI were re-examined and revealed some atypical values, which may indeed be due to analytical bias. These discrepancies call for intensified efforts to reliably quantify CLD and its TPs.

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 floral aroma components and molecular regulation mechanism of floral aroma formation in Phalaenopsis.

BACKGROUND: Most Phalaenopsis cultivars have almost no aroma, with a few exceptions. Phalaenopsis presents significant challenges in fragrance breeding due to its weak aroma and low fertility. It is therefore necessary to identify the aroma components and key regulatory genes in Phalaenopsis cultivars like 'Orange Beauty', 'Brother Sara Gold', 'Purple Martin', 'H026', 'SK16', 'SX098', and 'SH51', to improve the aroma of the common Phalaenopsis. RESULTS: Floral aroma components were tested on nine Phalaenopsis species, using smell identification and headspace gas chromatography-mass spectrometry. The result showed that alcohols, esters, and alkenes were the key specific components in the different species and cultivar aromas and the aroma intensity and component content of cultivars with different colors were different. The main components of the floral aromas in Phalaenopsis were alcohols (including eucalyptol, linalool, citronellol, and 1-hexanol), esters (including hexyl acetate, leaf acetate, and dibutyl phthalate), alkenes (including pinene and sabinene) and arenes (like fluorene). The transcriptome of flowers in the bud stage and bloom stage of P. 'SH51' was sequenced and 5999 differentially expressed genes were obtained. The contributions of the phenylpropionic acid/phenyl ring compound and the terpene compound to the aroma were greater. Sixteen genes related to phalaenopsis aroma were found. TC4M, PAL, CAD6, and HR were related to phenylpropanoid synthesis pathway. SLS, TS10, and P450 were related to the synthesis pathway of terpenes. TS10 and YUCCA 10 were involved in tryptophan metabolism. CONCLUSION: This is the first report on the floral aroma components and regulatory genes in Phalaenopsis. The proposed method and research data can provide technical support for Phalaenopsis breeding. © 2024 Society of Chemical Industry.

Exploring microbial and moist-heat effects on Pu-erh tea volatiles and understanding the methoxybenzene formation mechanism using molecular sensory science.

Piling fermentation (PF) is crucial for Pu-erh tea aroma, yet its microbial and moist-heat impact on aroma quality is poorly understood. Solid-phase microextraction, solvent-assisted flavor evaporation, and gas chromatography-mass spectrometry were used to detected and analyses the samples of sun-green green tea, sterile PF and spontaneous PF. Microbiological action promotes the formation of stale aromas. Moist-heat action promotes the formation of plum-fragrance and sweet aroma. 20 microbial markers and 28 moist-heat markers were screened from 184 volatile components. Combining odor activity values and gas chromatography-olfactometry, 22 aroma-active compounds were screened (1,2,3-trimethoxybenzene, linalool, 1,2,4-trimethoxybenzene …), and analyzed during PF processing. Aroma omission and addition experiments verified its importance. Gallic acid addition experiments successfully verified that microorganisms are the main contributors to the synthesis of methoxybenzenes. Finally, Blastobotrys, Rasamsonia, and Thermomyces showed positive correlation with the synthesis of 1-ethyl-4-methoxybenzene, 1,2,4-trimethoxybenzene, 1,2,3-trimethoxybenzene, and 1,2-dimethoxybenzene. The formation mechanism of Pu-erh tea's aroma was clarified. Exploring microbial and moist-heat effects on Pu-erh tea volatiles and understanding the methoxybenzene formation mechanism using molecular sensory science.

Long-term escape behavior and release mechanism of organic emissions from asphalt materials.

In the context of carbon neutrality and carbon peaking, investigating the long-term escape behavior and release mechanism of organic emissions from asphalt materials can contribute to the development of environmentally sustainable asphalt pavements. In this study, the long-term emission behavior and release mechanism of organic emissions from asphalt materials were unraveled by combining the headspace gas chromatography-mass spectrometry (HS-GC-MS), differential scanning calorimetry (DSC), fluorescence microscopy (FM), and Fourier transform infrared spectroscopy (FTIR) tests. The results demonstrate that the pressure aging vessel (PAV) test and the ultraviolet (UV) aging test can result in a notable reduction in the concentration of organic emissions from asphalt materials, respectively. This indicates that asphalt pavements can potentially release a substantial quantity of organic emissions during their long-term service life. Besides, the aging mechanism of asphalt materials is established to unravel the release mechanism of organic emissions from asphalt materials. Aging increases the probability of organic emissions being released and volatilized from asphalt materials, which leads to the organic emissions from asphalt materials being more likely to be released and volatilized. Consequently, the aging process facilitates a greater release and volatilization of organic emissions from asphalt materials, resulting in a decrease in the detected concentration of these emissions after aging.

Sequential Fermentation in Red Wine cv. Babic Production: The Influence of Torulaspora delbrueckii and Lachancea thermotolerans Yeasts on the Aromatic and Sensory Profile.

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

Discrepancies between the stated contents and analytical findings for electronic cigarette liquid products: Identification of the new cannabinoid, Δ9-tetrahydrocannabihexol acetate.

A number of synthetic cannabinoids have been appearing in the recreational drug market for more than a decade. Recent additions are so-called semi-synthetic cannabinoids, and they structurally closely resemble the main psychoactive component of cannabis, Δ9-tetrahydrocannabinol. Knowledge of new (semi-)synthetic cannabinoids is essential to help identify them in authentic forensic case samples. Therefore, the aim of the study was to examine two commercially available electronic cigarette liquid products claiming to contain cannabinoids and characterize the structures of the main compounds. The liquid products were analyzed by gas chromatography-mass spectrometry (GC-MS), GC-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), and liquid chromatography-high-resolution mass spectrometry (LC-HRMS). In product A, typical cannabinoids (cannabidiol, cannabigerol, and cannabinol) and terpenes (α-caryophyllene and ß-caryophyllene) were identified by comparison with reference materials. An unknown peak was isolated by semi-preparative high-performance LC, analyzed by nuclear magnetic resonance (NMR) spectroscopy, and identified to be Δ9-tetrahydrocannabihexol acetate (Δ9-THCH-O). To the authors' knowledge, this is the first report of the identification of Δ9-THCH-O in commercially available products. Another compound estimated as cannabihexol acetate was also detected. In product B, cannabidiol, cannabinol, α-caryophyllene, and ß-caryophyllene were identified, while two unknown peaks were estimated as tetrahydrocannabidiol isomers. Despite products A and B being labeled to contain "60% HHCPM" and "80% 10-OH-HHC," respectively, no such compounds were detected. The findings of this study could help detect Δ9-THCH-O in case samples and highlight the need to keep monitoring commercial products to identify new drugs, while warning that the package labels cannot be trusted.

Insects' perception and behavioral responses to plant semiochemicals.

Insect-plant interactions are shaped by the exchange of chemical cues called semiochemicals, which play a vital role in communication between organisms. Plants release a variety of volatile organic compounds in response to environmental cues, such as herbivore attacks. These compounds play a crucial role in mediating the interactions between plants and insects. This review provides an in-depth analysis of plant semiochemicals, encompassing their classification, current understanding of extraction, identification, and characterization using various analytical techniques, including gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), nuclear magnetic resonance (NMR) spectroscopy, and infrared (IR) spectroscopy. The article also delves into the manner in which insects perceive and respond to plant semiochemicals, as well as the impact of environmental factors on plant odor emission and insect orientation. Furthermore, it explores the underlying mechanisms by which insects perceive and interpret these chemical cues, and how this impacts their behavioral responses, including feeding habits, oviposition patterns, and mating behaviors. Additionally, the potential applications of plant semiochemicals in integrated pest management strategies are explored. This review provides insight into the intricate relationships between plants and insects mediated by semiochemicals, highlighting the significance of continued research in this field to better understand and leverage these interactions for effective pest control.

Volatile Compounds for Discrimination between Beef, Pork, and Their Admixture Using Solid-Phase-Microextraction-Gas Chromatography-Mass Spectrometry (SPME-GC-MS) and Chemometrics Analysis.

This study addresses the prevalent issue of meat species authentication and adulteration through a chemometrics-based approach, crucial for upholding public health and ensuring a fair marketplace. Volatile compounds were extracted and analyzed using headspace-solid-phase-microextraction-gas chromatography-mass spectrometry. Adulterated meat samples were effectively identified through principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA). Through variable importance in projection scores and a Random Forest test, 11 key compounds, including nonanal, octanal, hexadecanal, benzaldehyde, 1-octanol, hexanoic acid, heptanoic acid, octanoic acid, and 2-acetylpyrrole for beef, and hexanal and 1-octen-3-ol for pork, were robustly identified as biomarkers. These compounds exhibited a discernible trend in adulterated samples based on adulteration ratios, evident in a heatmap. Notably, lipid degradation compounds strongly influenced meat discrimination. PCA and PLS-DA yielded significant sample separation, with the first two components capturing 80% and 72.1% of total variance, respectively. This technique could be a reliable method for detecting meat adulteration in cooked meat.

Lipidomic Analysis Reveals Branched-Chain and Cyclic Fatty Acids from Angomonas deanei Grown under Different Nutritional and Physiological Conditions.

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

Combined perceptual and chemical analyses show no compelling evidence for ovulatory cycle shifts in women's axillary odour.

Although men's attraction to women's body odour has been suggested to vary over the ovulatory cycle, peaking around the fertile window, we still lack methodologically robust evidence corroborating this effect. Further, the chemical underpinnings of male preference for the odour of ovulating women remain unknown. Here, we combined perceptual and chemical analyses to investigate the axillary odour of naturally cycling women over 10 days, covering the gradual change in fertility across the ovulatory cycle with a focus on fertile days. The fertile state was confirmed by urinary ovulation tests as well as salivary oestradiol and progesterone levels. Men rated the scent of unfamiliar women, resembling a first encounter. We used multivariate analyses to relate variation in both odour ratings and chemical composition to female conception probability, temporal distance to ovulation and ovarian hormone levels. Our results provide no evidence that males prefer the odour of fertile women. Furthermore, the volatile analysis indicated no link between axillary odour composition and current fertility status. Together, our results showed no convincing support for a chemical fertility cue in women's axillary odour, questioning the presence of olfactory fertility information that is recognizable during first encounters in modern humans.

Assessing residual fragrances on skin after body washing: Optimization of an analytical method using solid-phase microextraction coupled with gas chromatography-mass spectrometry.

OBJECTIVE: The aim of this study is to develop and optimize a method for evaluating the persistence of residual fragrance after body washing, addressing a significant requirement in the development of personal care products. The main objective is to establish a reliable, sensitive and reproducible analytical technique to assess fragrance longevity on skin post-use of body wash products. METHODS: Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) is used to analyse residual fragrances. We investigate the extraction efficiencies of various SPME fibres and compare different methods for sampling skin-emitted fragrances, including tape stripping and sealed glass funnels. A controlled body-washing procedure is implemented to standardize the cleansing process. RESULTS: Our findings indicate that the relative standard deviation for measuring five distinct fragrances is within the range of 3%-14%, highlighting the precision of the method. A notable variance exists in the extraction efficiency of fragrances using different types of SPME fibres, with some exhibiting over a threefold difference. Furthermore, the glass funnel method for fragrance collection demonstrates an 11.7 times greater sensitivity to galaxolide than that of the tape-stripping method. Residual fragrances with base notes as the main components can be detected on the skin up to 24 h after body washing. CONCLUSION: The optimized method for residual fragrance evaluation developed in this study offers a robust tool for analysing fragrance components persisting on the skin for up to 24 h post-wash. This advancement facilitates a deeper understanding of fragrance longevity in personal care products, enabling comparative analyses between different products.

OBJECTIF: l'objectif de cette étude est de développer et d'optimiser une méthode d'évaluation de la persistance du parfum résiduel après la toilette du corps, répondant à une exigence significative dans le développement de produits de soins personnels. L'objectif principal est d'établir une technique analytique fiable, sensible et reproductible pour évaluer la longévité des parfums sur la peau après utilisation de produits de toilette pour le corps. METHODES: la microextraction en phase solide de l'espace de tête (HS­SPME) couplée à la chromatographie en phase gazeuse­spectrométrie de masse (GC­MS) est utilisée pour analyser les parfums résiduels. Nous étudions l'efficacité de l'extraction de diverses fibres SPME et nous comparons différentes méthodes d'échantillonnage des senteurs émises par la peau, y compris le stripping sur ruban adhésif et les entonnoirs en verre scellés. Une procédure contrôlée de lavage du corps est mise en place pour standardiser le processus de nettoyage. RÉSULTATS: nos résultats indiquent que l'écart­type relatif pour mesurer cinq parfums distincts se situe dans la plage de 3% à 14%, ce qui souligne la précision de la méthode. Une variance notable existe dans l'efficacité d'extraction des parfums utilisant différents types de fibres de SPME, certaines présentant plus d'un triplement de différence. En outre, la méthode de l'entonnoir en verre pour la collecte des parfums démontre une sensibilité au galaxolide 11,7 fois supérieure à celle de la méthode de stripping sur ruban adhésif. Les parfums résiduels avec des notes de fond comme principaux composants peuvent être détectés sur la peau jusqu'à 24 h après le lavage du corps. CONCLUSION: la méthode optimisée pour l'évaluation du parfum résiduel développée dans cette étude offre un outil fiable pour analyser les composants du parfum persistant sur la peau jusqu'à 24 heures après le lavage. Cette avancée offre une meilleure compréhension de la longévité des parfums dans les produits de soins personnels, permettant des analyses comparatives entre les différents produits.

Kigelia africana fruit fractions inhibit in vitro alpha-glucosidase activity: a potential natural alpha-glucosidase inhibitor.

BACKGROUND: Diabetes affects 75% of people in low-income countries, where conventional drugs like metformin are available, but newer drugs like alpha-glucosidase inhibitors are not accessible to most Southern African patients. AIM: To evaluate the α-glucosidase and α-amylase inhibitory activities of fractionated aqueous extracts of Kigelia africana fruit (KAFE) and their phytochemical fingerprints using gas chromatography-mass spectrometry (GC-MS). MATERIALS AND METHODS: We studied K. africana fruit fractions' inhibitory effects on alpha-glucosidase and alpha-amylase using bioassay-guided fractionation, and analyzed their phytochemical profiles with GC-MS. KEY FINDINGS: Both the aqueous extract and ethyl acetate fraction of the aqueous extract exhibited a low dose-dependent inhibition of alpha-amylase activity (p < 0.0001). At a concentration of 500 µg/mL, the aqueous extract caused an alpha-glucosidase inhibition of 64.10 ± 2.7%, with an estimated IC50 of 193.7 µg/mL, while the ethyl acetate fraction had an inhibition of 89.82 ± 0.8% and an estimated IC50 of 10.41 µg/mL. The subfraction G, which had the highest alpha-glucosidase inhibitory activity at 85.10 ± 0.7%, had significantly lower activity than the ethyl acetate fraction. The most bioactive fraction was found to contain 11"(2-cyclopenten-1-yl) undecanoic acid, ( +)- and cyclopentane undecanoic acid as well as the indole alkaloids Akuammilan-17-ol-10-methoxy, N-nitroso-2-methyl-oxazolidine and epoxide Oxirane2.2″ -(1.4-butanediyl) bis-. CONCLUSION: The K. africana fruit fraction demonstrated significant alpha-glucosidase inhibitory activity, while its alpha-amylase inhibitory activity was limited. This study suggests a potential natural alpha-glucosidase inhibitor and phytocompounds that could serve as leads for developing antidiabetic agents.

Quantification of tire wear particles in road dust based on synthetic/natural rubber ratio using pyrolysis-gas chromatography-mass spectrometry across diverse tire types.

Increase in road traffic leads to increased concentrations of tire-wear particles (TWPs), a prominent source of microplastics from vehicles, in road dust. These particles can re-enter the atmosphere or move into aquatic ecosystems via runoff, impacting the environment. Consequently, accurately assessing and managing TWP levels in road dust is crucial. However, the ISO method (ISO/TS 20593 and 21396) uses a constant ratio of styrene-butadiene rubber (SBR) to natural rubber (NR) for all tires, disregarding the variability in tire composition across different types and brands. Our study found substantial SBR content (15.7 %) in heavyweight truck tires, traditionally believed to be predominantly NR. We evaluated the SBR/NR content in 15 tire types and proposed a method to more accurately evaluate TWP concentrations in road dust from five different locations. Our findings suggest that the conventional ISO method may underestimate the concentrations of TWP due to its reliance on a static ratio of SBR/NR. This study underscores the necessity for a more flexible approach that can adapt to the variability in SBR and NR content across different tire types. By delineating the limitations inherent in current assessment methods, our research contributes to a more adaptable understanding of TWP concentrations in road dust. This advancement prompts the development of a revised methodology that more accurately reflects the diverse compositions of tire rubber in environmental samples.

Quantifying fecal and plasma short-chain fatty acids in healthy Thai individuals.

Short-chain fatty acids (SCFAs) are involved in important physiological processes such as gut health and immune response, and changes in SCFA levels can be indicative of disease. Despite the importance of SCFAs in human health and disease, reference values for fecal and plasma SCFA concentrations in healthy individuals are scarce. To address this gap in current knowledge, we developed a simple and reliable derivatization-free GC-TOFMS method for quantifying fecal and plasma SCFAs in healthy individuals. We targeted six linear- and seven branched-SCFAs, obtaining method recoveries of 73-88% and 83-134% in fecal and plasma matrices, respectively. The developed methods are simpler, faster, and more sensitive than previously published methods and are well suited for large-scale studies. Analysis of samples from 157 medically confirmed healthy individuals showed that the total SCFAs in the feces and plasma were 34.1 ± 15.3 µmol/g and 60.0 ± 45.9 µM, respectively. In fecal samples, acetic acid (Ace), propionic acid (Pro), and butanoic acid (But) were all significant, collectively accounting for 89% of the total SCFAs, whereas the only major SCFA in plasma samples was Ace, constituting of 93% of the total plasma SCFAs. There were no statistically significant differences in the total fecal and plasma SCFA concentrations between sexes or among age groups. The data revealed, however, a positive correlation for several nutrients, such as carbohydrate, fat, iron from vegetables, and water, to most of the targeted SCFAs. This is the first large-scale study to report SCFA reference intervals in the plasma and feces of healthy individuals, and thereby delivers valuable data for microbiome, metabolomics, and biomarker research.

Characterization of the key flavor compounds in cream cheese by GC-MS, GC-IMS, sensory analysis and multivariable statistics.

The aroma types of cream cheese affect its commercial value and consumer acceptability. However, the types of volatile substances and sensory characteristics of cream cheese at different fermentation stages are still unclear. Therefore, in this study, headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) were used to analyze the volatile substances in cream cheese fermentation. Orthogonal partial least squares discriminant analysis (OPLS-DA), odor activity value (OAV), relative odor activity value (ROAV) and variable projection importance (VIP) were used to identify the characteristic flavor substances in cream cheese fermentation. Finally, the relationship between key flavor substances and sensory characteristics was determined by partial least squares (PLS) analysis. A total of 34 and 36 volatile organic compounds were identified by HS-SPME-GC-MS and HS-GC-MS, respectively, and 14 characteristic flavor substances were found, based on VIP, ROAV and OAV models. Combined with sensory analysis and flavor substance changes, it was found that the cream cheese fermented for 15 d had the best flavor and taste. This study reveals the characteristics and contribution of volatile substances in cream cheese at different fermentation stages, which provides new insights into improving flavor and quality control.

Characterization and discrimination of the taste and aroma of Tibetan Qingke baijiu using electronic tongue, electronic nose and gas chromatography-mass spectrometry.

Consumers rely on flavor characteristics to distinguish different types of Qingke Baijiu (QKBJ). Clarifying QKBJ's traits enhances its recognition and long-term growth. Thus, this study analyzed eight QKBJ samples from different regions of Tibet (Lhasa, Sannan, Shigatse, and Qamdo) using GC-MS, electronic nose and electronic tongue. The radar charts of the electronic tongue and electronic nose revealed highly similar profiles for all eight samples. Fifteen common compounds were found in all samples, with the main alcohol compounds being 3-Methyl-1-butanol, 1-hexanol, isobutanol, 1-butanol, 1-nonanol, and phenylethyl alcohol, imparting fruity, floral, and herbal aromas. However, the Sannan samples had higher total alcohol content than total ester content, emphasizing bitterness. Lhasa1 exhibited the most prominent sweetness, Lhasa2 the most noticeable sourness, and Qamdo the most pronounced umami. Lhasa3 and Lhasa4 had total acid content second only to total ester content. Tyd had the highest alkanes, while Lhasa had most aldehydes among samples.