Search Results (5,644)

Proeulia auraria (Lepidoptera: Tortricidae) is a native Chilean moth and a significant pest of several fruit crops. Its sexual communication relies on pheromones, of which (E)-11-tetradecenyl acetate (E11-14:OAc) is the major component, but the mechanisms regulating its production and biosynthetic pathways are poorly understood. We studied the effect of pheromone-biosynthesis-activating neuropeptide (PBAN) on pheromone production and its biosynthesis through isotopic labeling using deuterated fatty acids, which were topically applied to the pheromone gland. Gas chromatography–mass spectrometry (GC-MS) analysis was then performed. PBAN application increased E11-14:OAc by up to eight times. In labeling experiments with [16,16,16-²H₃]hexadecanoic acid (D₃-16:acid), the mass spectrum of E11-14:OAc showed a shifted ion at m/z 197 and a natural ion at m/z 194. These results indicated the incorporation of three deuteriums into the terminal methyl group and that chain shortening from palmitic acid to the 14-carbon skeleton occurs through β-oxidation from the carboxyl end. Deuterium incorporation was also detected after D₃-18:acid and D₃-14:acid application. The findings provide the first direct evidence regarding the precursors and direction of chain shortening in the pheromone biosynthesis of P. auraria. The information contributes to our understanding of its chemical communication and could lay the foundation for the development of pheromone-based control tools. Full article

Fatty acid composition contributes to the nutritional characteristics of goat meat, but its variation among anatomical muscles remains insufficiently characterized. This exploratory study determined fatty acid profiles in six skeletal muscles and serum from nine 10-month-old castrated male Tianfu goats raised under a common farm feeding and management regimen using targeted gas chromatography–tandem mass spectrometry (GC–MS/MS). Oil Red O staining was also performed for semiquantitative histological analysis of the six skeletal muscles. Thirty-four fatty acids were detected in skeletal muscle, with oleic acid (C18:1n9c), palmitic acid (C16:0), stearic acid (C18:0), and linoleic acid (C18:2n6c) as the predominant components. Monounsaturated fatty acids (MUFAs) constituted the largest fatty acid subclass in skeletal muscle, whereas saturated fatty acids (SFAs) predominated in serum. The longissimus dorsi (LD) and supraspinatus (SS) showed relatively stronger Oil Red O-positive staining. The total fatty acid concentration was significantly higher in SS than in the semimembranosus (SM) muscle (18,282.09 ± 8516.92 vs. 5831.66 ± 3310.31 μg/g, p < 0.05). SS also contained higher concentrations of polyunsaturated fatty acids (PUFAs), SFAs, and MUFAs than SM (1065.99 ± 425.52 vs. 421.00 ± 103.96, 6973.64 ± 3325.02 vs. 2374.02 ± 1383.12, and 10,242.46 ± 4812.55 vs. 3036.65 ± 1841.48 μg/g, respectively; p < 0.05). Twenty-seven fatty acids were shared between serum and skeletal muscle, and correlation analysis with false discovery rate (FDR) correction revealed exploratory muscle-specific serum–muscle association patterns. Overall, Tianfu goat skeletal muscles exhibited a shared MUFA-dominant profile but clear anatomical variation in fatty acid abundance, with SS and LD showing potential for nutritional differentiation and value-added utilization. Full article

Lamiaceae plants produce essential oils (EOs) with diverse chemical compositions and biological activities. This study investigated the volatile composition and multiple biological activities of EOs from 13 Lamiaceae species. EOs were obtained by hydrodistillation and characterized by gas chromatography–mass spectrometry (GC-MS), followed by hierarchical clustering and principal component analysis. Antioxidant, antibacterial, cytotoxic, and anti-inflammatory activities were evaluated using in vitro and murine models. GC-MS analysis revealed substantial interspecific variation in volatile composition, with Origanum vulgare characterized by carvacrol and limonene, Thymus spp. by thymol, Rosmarinus officinalis by eucalyptol and α-pinene, Mentha canadensis by L-menthol, and Perilla frutescens by perillaldehyde. Scutellaria baicalensis, Elsholtzia ciliata, Phlomis mongolica, and Schizonepeta tenuifolia showed distinctive profiles associated with limonene and isopulegone, nepetalactone, pulegone, and anethole and anisaldehyde, respectively. Multivariate analysis further separated the 13 oils into three chemotype groups: a carvacrol-rich Origanum group, a Scutellaria and Thymus group enriched in sesquiterpenes or thymol, and a group comprising the remaining six genera dominated by shared monoterpene hydrocarbons. Most EOs exhibited substantial 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, with Rosmarinus officinalis and Perilla frutescens showing the strongest activity, with IC₅₀ values of 2.14 and 2.08 μg/mL, respectively. Origanum vulgare, Thymus citriodorus, Thymus vulgaris, and Thymus mongolicus displayed strong antibacterial activity against five pathogens, with minimum inhibitory concentration (MIC) values ranging from 2 to 8 μg/mL. Cytotoxicity assays showed potent activity against HepG2 and LNCaP cells, with IC₅₀ values ranging from 0.31 to 0.95 μg/mL. Elsholtzia ciliata and Perilla frutescens exhibited particularly strong potency, with IC₅₀ values ranging from 0.31 to 0.40 μg/mL. In a murine skin inflammation model, selected EOs significantly reduced inflammation-related markers, including COX-2, TNF-α, NF-κB, IKK, Akt, and PKC. Correlation analysis identified significant associations of carvacrol, thymol, and β-linalool with antibacterial activity, whereas no significant associations were observed between individual major constituents and antioxidant or cytotoxic activity after false discovery rate (FDR) correction. Overall, the 13 Lamiaceae EOs displayed distinct chemical profiles and activity patterns, providing a basis for further investigation of their bioactive constituents and potential applications. Full article

The cuticular wax of ‘Hupingzao,’ an important economic crop in China, not only constitutes a key factor in determining the appearance quality and gloss of the fruit but also plays a vital role in regulating water evaporation and resisting biotic and abiotic stresses. In this study, ‘Hupingzao’ fruit produced during the white−ripe (WR) and full−red (FR) periods were used as study materials. The key genes and components of wax development were screened using a combination of transcriptomics and metabolomics. Enrichment analysis was performed on the differential genes and metabolites, and the fatty acid biosynthesis and elongation pathways were selected for further study. A series of key candidate genes in the de novo synthesis, elongation, and subsequent modification pathways of fatty acids were identified, such as acetyl−CoA carboxylase (ACCase), fabF (β−Ketoacyl−ACP Synthase II), and β−ketoacyl−CoA synthase (KCS). To further explore the mechanism of jujube wax biosynthesis, GC−MS (gas chromatography–mass spectrometry) was used to determine and analyze the content and composition of the wax after it was treated with gibberellin and paclobutrazol. The results showed that spraying the plants with GA₃ significantly upregulated the expression of genes involved in fatty acid de novo synthesis and elongation such as accC (Acetyl−CoA Carboxylase, Biotin Carboxylase Subunit), fabD (Malonyl−CoA:ACP Transacylase), fabG (β−Ketoacyl−ACP Reductase), fabI (Enoyl−ACP Reductase), ACSL (Long−chain Acyl−CoA Synthetase), and KCS and increased the content of dodecanoic acid, behenic acid, lignoceric acid, and hexacosanoic acid. These results suggest that the GA signal may participate in the upregulation of fatty acid synthesis. In this study, we systematically constructed a molecular map of wax fatty acid metabolism during the fruit development stage of the ‘Hupingzao’ variety, providing an important theoretical basis and candidate genes for future directional regulation of wax components via molecular breeding or cultivation measures. Full article

Phytohormones play a vital role in plant responses to biotic stresses. Although phytohormone determination mainly employs ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS), its high costs and technical requirements limit utility, whereas gas chromatography–mass spectrometry (GC-MS) is more widely used. To determine jasmonic acid (JA), salicylic acid (SA), and indole-3-acetic acid (IAA) in tea plants, a GC-MS method was developed, including selection of silylating reagents and establishment of metabolism quenching and purification methods. SA, JA, and IAA contents in tea leaves increased significantly after storage at −80 °C or extraction at room temperature. These increases were prevented by immersing samples in a 95 °C water bath. Quantification limits for SA, JA, and IAA were 0.020 ng mg⁻¹, 0.015 ng g⁻¹, and 0.015 ng g⁻¹, similar to or exceeding those obtained by UHPLC-MS/MS. Recoveries and RSD were 93.1–98.9% and 2.1–9.9%, respectively. Only 10 mg of tea leaves was sufficient for simultaneous analysis of the three phytohormones. The JA response to geometrids was strong compared with the SA response, whereas the opposite trend was observed for leafhoppers. The systemic responses of JA and SA were rapid, similar to the local response. These results indicate that the proposed method is sensitive and reliable. Full article

Background/Objectives: Chaulmoogra oil (ChO), from Hydnocarpus wightianus Blume seeds, is returning to use as the lipid phase of transdermal carriers, yet no pharmacopoeial monograph governs it. This work asked whether lipid classes associated with hydrolysis and oxidation distinguish oils that a fatty acid specification would not separate. Methods: Three commercial products, each analyzed once, were profiled by ultra-performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS), and two of them also by gas chromatography-mass spectrometry (GC-MS). Growth inhibition was tested by broth dilution. Results: Cyclopentenyl acids dominated the fatty acid composition. In one product (ChO 2), fatty acyl esters of hydroxy fatty acids (FAHFA) accounted for about 14% of the annotated negative-mode signal, against 2 and 4% in the others, and diacylglycerols for 1.3% of the positive-mode signal, against 0.3 and 0.7%. The acid value (1.9 to 2.8 mg KOH/g) and the share of oxidized triacylglycerols were instead highest in ChO 3. No measurable growth inhibition of Escherichia coli, Bacillus cereus or Candida albicans by the crude oils was detected up to 250 µg/mL. Conclusions: A specification based on fatty acid composition alone would not separate these products, and the FAHFA and diacylglycerol shares are proposed as candidate attributes associated with hydrolysis and oxidation that require validation. Full article

Use of antidepressant medication has increased substantially nowadays. Investigations of their photostability in aqueous environment are therefore needed both for shelf life assessment of liquid pharmaceutical formulations and for development of wastewater remediation technologies. In this work, the comparative kinetics of photodegradation of five tricyclic antidepressants (TCAs) in aqueous solution was studied under direct photolysis using UVA, UVB, and UVC sources, respectively. A gas chromatography–mass spectrometry (GC-MS) method was developed and validated intra-laboratory for accurate quantification of the five TCAs (amitriptyline hydrochloride AMI, doxepin hydrochloride DOX, imipramine hydrochloride IMI, clomipramine hydrochloride CLO, trimipramine maleate TRI) in the course of photodegradation. UVC photolysis yielded the highest rates of photodegradation, followed by UVB and then UVA. The molecular structure and UV absorption characteristics of individual TCAs were shown to influence photodegradation rates as well. Specifically, heteroatoms (N, O, Cl) present in the molecule and redshifted UV absorption bands increased photosensitivity typically in the order: AMI < IMI < TRI < CLO < DOX. The effect that some mono- and polycarboxylic acids dissolved in the aqueous solutions had on TCA photodegradation kinetics under UVC was also investigated and, for most TCAs, rates were faster and durations required for their complete photodegradation decreased generally in the order: citric > oxalic > maleic > benzoic acid. Furthermore, citric acid was reused for a second round of TCA photodegradation and showed rate enhancement effects very close to those exhibited in the first round. Full article

Helichrysum italicum (Roth) G. Don subsp. italicum is one of the most valuable Mediterranean aromatic species owing to its essential oil, which is widely used in pharmaceutical, cosmetic, and nutraceutical applications. However, comparative phytochemical investigations simultaneously addressing essential oils and hydrosols from geographically isolated natural populations remain limited. In this study, we investigated essential oils and hydrosols from pooled plant material collected at six sites across the Tuscan Archipelago (Capraia, Elba, and Giglio Islands) by gas chromatography–mass spectrometry (GC–MS) and headspace solid-phase microextraction coupled with GC–MS (HS-SPME–GC–MS). The analyzed pooled site samples shared an essential-oil profile dominated by neryl acetate (24.90–34.01%), γ-curcumene (9.10–14.91%), α-pinene (5.05–14.17%), and neryl propionate (4.37–9.14%), while their relative abundances differed among the analyzed pooled site samples. Marked differences were observed among the hydrosol headspace profiles. Within the HS-SPME–GC–MS profiles, eucalyptol showed the highest relative peak-area contribution in the four Capraia pooled samples (39.13–94.56%), whereas the Elba profile was dominated by neryl acetate (56.36%). The Giglio profile was mainly characterized by nerol (29.81%), fenchyl alcohol (21.72%), and 4-terpineol (16.56%). Overall, the results provide complementary descriptive information on the volatile composition of the analyzed pooled site samples and identify candidate compositional patterns requiring validation through independent biological sampling and replicated distillations. Full article

In this study, we examined the multifaceted effects of sulfur dioxide (SO₂) on the postharvest preservation of durian and the underlying potential mechanism of disease resistance. Our results show that 2% SO₂ preserved the good quality of durian by inhibiting its respiration rate and ethylene production (day 15), reducing weight loss, and maintaining color, firmness, and ascorbic acid content. Furthermore, the volatile organic compounds (VOCs) were investigated further by gas chromatography-ion mobility spectrometry (GC-IMS). Ester compounds (fruity aroma of durian) were primarily intensified in SO₂-treated samples, while SO₂ weakened the content of volatile sulfur compounds. Certain antioxidant and antifungal VOCs, including alpha-terpinene, benzyl alcohol, 2-decanone, and 2-heptylfuran, may contribute to enhancing the disease resistance of durian. High-throughput sequencing (HTS) analysis indicated that SO₂ may enhance the disease resistance of durian by shifting the fungal community succession, which stabilized the relative abundance of Meyerozyma sp. and decreased the relative abundance of Alternaria sp. (on day 5), Verticillium sp. (on day 5), and Moesziomyces sp. (on day 5 and 10). Additionally, SO₂ induced the activities of defense-related enzymes, such as catalase (CAT), polyphenol oxidase (PPO), peroxidase (POD), chitinase (CHI), and β-1,3-glucanase (β-GLU), which may synergize with antifungal VOCs and fungal community succession to enhance durian disease resistance. These results clarify the potential distinct mechanisms of disease resistance of SO₂ and provide a scientific basis for the application of SO₂ in the postharvest preservation of durian fruits. Full article

The increasing occurrence of microplastics in environmental compartments such as water, soil, air, and food represents a growing challenge for environmental science and policy. Despite their ecological relevance, the reliable detection and quantification of microplastics are hampered by methodological variability, the lack of standards, and heterogeneous sample matrices. The wide range of available analytical methods results in datasets that are not directly comparable, thereby limiting the interpretability of current assessments. The aim of this review is therefore to systematically document and evaluate existing measurement methods for MPs in soil samples in order to support the development of standardized and practice-oriented analytical approaches. All fundamental operating principles of the analytical instruments—spectroscopic (Fourier Transform Infrared Spectroscopy (FTIR), Near-Infrared Spectroscopy (NIR) and Raman Spectroscopy), thermoanalytical (Pyrolysis–Gas Chromatography–Mass Spectrometry (Py-GC/MS), Thermal Extraction–Desorption Gas Chromatography–Mass Spectrometry (TED-GC-MS), and Differential Scanning Calorimetry—DSC), imaging, (Light Microscopy and Scanning Electron Microscopy—SEM), and fluorescence-based methods—are analyzed in details and compared. Our analysis shows that consistent quality control, particularly regarding preventing cross contamination during sampling, is essential to obtain reliable results. The developed flowchart supports structured methodological decision making and contributes to transparency and comparability in microplastic-related studies, but it does not replace detailed method planning. Full article

Although understanding aroma evolution during roasting is essential for optimizing roasting control and coffee quality, most studies have focused on only a few discrete roasting levels. In this study, high-performance liquid chromatography (HPLC), headspace solid-phase microextraction and gas chromatography–mass spectrometry (HS-SPME-GC–MS), and sensory evaluation were integrated to characterize changes in key non-volatile compounds, odor-active compounds, and cup quality of Arabica coffee from green beans (S0) through eight successive roasting stages (S1-S8). The results show that the total contents of soluble sugars and chlorogenic acids continuously decreased throughout the roasting process. Volatile compound (VOC) diversity increased until S5, while the total VOC concentration peaked at S7. A total of 47 VOCs showed OAVs > 1, and phenylethyl alcohol, furfuryl alcohol, furfural, phenol, and pyridine were identified as key discriminant markers. Cup quality improved progressively and reached its optimum at S4, characterized by balanced nutty, roasted hazelnut-like, and caramel-like notes, but declined thereafter as smoky and burnt–bitter characteristics intensified. The transition from S4 to S5 therefore represents a critical turning point in coffee aroma evolution during roasting. These findings provide a basis for optimizing roasting control and coffee aroma quality. Full article

Background/Objectives: This study examined urinary cholanoid profiles in a descriptive case series evaluated for suspected inborn errors of bile acid synthesis (IEBAS) or unexplained cholestasis. Methods: Urinary excretion of 66 bile acid metabolites was measured using liquid chromatography–tandem mass spectrometry (LC-MS/MS), and concentrations were interpreted as semi-quantitative estimates. In addition, cholesterol, cholestanol, and 7-dehydrocholesterol were analyzed by gas chromatography–mass spectrometry (GC-MS). Results: Five patients had genetically confirmed IEBAS: 3β-hydroxy-Δ5-C27-steroid dehydrogenase (HSD3B7) deficiency in 2 patients and cerebrotendinous xanthomatosis (CTX) in 3 patients. Two patients were subsequently diagnosed with biliary atresia and progressive familial intrahepatic cholestasis type 1. Other patients remained without a definitive etiological diagnosis. Of the two patients with genetically confirmed HSD3B7 deficiency, patient 1 showed a predominance of 3β-hydroxy-Δ⁵ bile acids (63.9% of total urinary bile acids), including sulfated dihydroxy-, glycine-conjugated dihydroxy-, and trihydroxy-Δ⁵ species. Patient 2 had an atypical urinary bile acid profile, with the 3β-hydroxy-Δ⁵ fraction dominated by a monohydroxy species. CTX patients had profiles with a different bile acid group composition; hydroxylated bile acids were reported in 2 patients, whereas no numerical result was reported for 1 patient. The 3β-hydroxy-Δ⁵ bile acid levels in 1 CTX patient were within the observed control range. Two patients also had differential profiles for hydroxylated and 3β-hydroxy-Δ⁵ bile acids, which provided biochemical findings for further etiological evaluation. The species assigned to glycoursodeoxycholic acid predominated in the urinary profiles of the five patients receiving ursodeoxycholic acid. Conclusions: Urinary cholanoid profiling may provide complementary biochemical information alongside the available clinical and genetic findings in the evaluation of suspected IEBAS. Full article

Hydroxylated polychlorinated biphenyls (OH-PCBs) are biologically active metabolites that may contribute to adverse respiratory outcomes, yet their effects on the developing lung remain poorly characterized. This study investigated the impact of 2,2′,5,5′-tetrachlorobiphenyl-4-ol (4-OH-PCB52), a human-relevant metabolite, on the pulmonary molecular pathways in postnatal day 28 female adolescent rats using a multi-omics approach. Animals were exposed to 4-OH-PCB52 (sham; low 1%; medium 5%; high 10%; (w/w)) via a subcutaneous implant release system for 28 days. Targeted analysis by gas chromatography–tandem mass spectrometry (GC-MS/MS) detected 4-OH-PCB52 in the medium 5% and high 10% exposure dose groups. At both higher doses, proteomic profiling revealed significant alterations in protein markers related to pulmonary post-transcriptional regulation, metabolism and chemical biotransformation, immunity and inflammation, oxidative stress and programmed cell death, and surfactant production and mucociliary clearance. In contrast, RNA sequencing did not identify differentially expressed genes. Collectively, these findings demonstrate that adolescent exposure to 4-OH-PCB52 perturbs key molecular markers associated with lung homeostasis, with potential implications for altered lung development and increased susceptibility to respiratory disorders during adulthood. Full article

Xenon (Xe) is an inert noble gas receiving increasing attention in medical research due to its anesthetic properties, ability to regulate metabolic processes, and broad organoprotective effects. Due to its small size and non-covalent intermolecular interactions, Xe can be encapsulated within α-cyclodextrin (α-CD). In this study, we combine a theoretical study based on molecular mechanics (MM) and molecular dynamics (MD) simulations with the synthesis and characterization of the α-CD/Xe inclusion complex. During the MD simulations, surface interactions and the formation of inclusion complexes, with Xe atoms encapsulated within the α-CD cavity, were observed in aqueous solution. As the Xe concentration in water increased, α-CD/Xe inclusion complexes with 1:1, 1:2, and 1:3 stoichiometries were formed and remained stable over time, suggesting increasingly effective encapsulation at higher pressures. Following this computational investigation, experimental work was conducted to synthesize and characterize the α-CD/Xe inclusion complex using a liquid-phase encapsulation method. The complexes were prepared at Xe loading pressures of 2, 4, 6, and 8 bar. Thermogravimetric analysis (TGA) revealed weight loss between 100 and 200 °C. The effective encapsulation of Xe was also confirmed by solid-phase microextraction coupled with gas chromatography–mass spectrometry (SPME-GC-MS), which detected the characteristic m/z signals of Xe and allowed monitoring of its release over time upon contact with aqueous solution. Full article

Lyme neuroborreliosis (LNB), caused by Borrelia garinii, often leads to persistent neurological deficits, yet early diagnosis remains insensitive and the temporal metabolic changes in the infected brain are largely unexplored. In this study, a murine model of B. garinii infection was established using 80 female BALB/c mice, and brain tissues were collected at acute 7 (days post-infection, DPI), mid- (15 and 21 DPI), and chronic (30 DPI) stages for untargeted gas chromatography–time-of-flight mass spectrometry (GC-TOF-MS) metabolomics. Thirty-one differential metabolites were identified, with downregulated metabolites predominating acutely and upregulated metabolites prevailing chronically. Twelve common metabolites, including creatine, lysine, and galactose derivatives, were consistently altered. KEGG analysis revealed disrupted amino acid metabolism, particularly valine, leucine, and isoleucine biosynthesis (ko00290), arginine and proline metabolism (ko00330), and aminoacyl-tRNA biosynthesis (ko00970). ROC analysis identified five candidate biomarkers, hydroxylamine, 2,3-dihydroxypyridine, galactose 1, galactose 2, and monostearin, with high diagnostic accuracy. This study provides a comprehensive temporal metabolomic landscape of the brain during B. garinii infection, revealing time-dependent metabolic reprogramming with sustained disruptions in amino acid and energy metabolism, and offering candidate biomarkers for improved diagnosis of central nervous system involvement in Lyme disease. Full article