Search Results (2,923)

Walnut oil is growing in consumer demand due to its rich nutritional profile; however, its fatty acid composition exhibits an imbalanced SFA:MUFA:PUFA ratio (0.13:0.18:1). To improve the fatty acid balance using locally available vegetable oils in Xinjiang, we investigated the effects of blending walnut oil with linseed oil, safflower seed oil, sunflower seed oil, rapeseed oil, peanut oil, and soybean oil on physicochemical indexes, fatty acid composition, and bioactive components. Aroma characteristics were assessed by E-nose and HS-GC-IMS. The results showed that the acid value and peroxide value of the blended oil decreased, while the content of vitamin E and squalene increased inversely. The ratio of ω-6/ω-3 maintain steadily at 4–6:1, and the ratios of SFA, MUFA, and PUFA were close to 0.27:1:1. Significant differences were observed between the aroma characteristics of walnut oil and the blended oil. HS-GC-IMS identified 85 volatile organic compounds (VOCs), among which walnut oil had a higher content of alcohols, aldehydes, and ketones, with 4-hydroxy-5-ethyl-2-methyl-3(2H)-furanone as its characteristic aroma compound. The acetophenone serves as the key aroma component after blending, and the unique flavor components of each base oil (e.g., 4-nonanone in linseed oil, 3-methyl-2-pentanone in rapeseed oil, etc.) exert a synergistic effect after rationing to present a composite aroma characteristic of blended oils, which mainly consists of 3-methylbutyl butyrate and 4-ethylphenol. Full article

The integration of non-thermal plasma (NTP) with heterogeneous catalysis has emerged as a promising strategy for the efficient abatement of industrial volatile organic compounds (VOCs), overcoming key limitations of conventional thermal and standalone plasma technologies. This review provides a comprehensive overview of the synergistic mechanisms in NTP-catalytic systems, with particular emphasis on the bidirectional interactions between plasma and the catalyst. Specifically, plasma can activate catalysts through surface defect generation and improved metal dispersion, while catalysts, in turn, modulate plasma characteristics via localized electric field enhancement and electron energy redistribution. Furthermore, this synergy spans multiple spatiotemporal scales, linking ultrafast electron dynamics with macroscopic catalytic performance, and atomic-scale active sites with reactor-level behavior. Based on these mechanistic insights, rational catalyst design strategies are systematically discussed, including transition metal oxides, noble metals, perovskites, and metal–organic frameworks. Finally, key challenges related to catalyst deactivation, energy efficiency, and process scalability are highlighted. Future perspectives are proposed, focusing on advanced in situ diagnostics and AI-assisted material discovery to accelerate the practical implementation of NTP-catalytic technologies for sustainable VOC removal. Full article

For thousands of years glass packaging for wine has traditionally been associated with quality and remains used today as an inert and recyclable container. However, alternative containers such as aluminum cans and polyethylene terephthalate (PET) bottles have been gaining traction over the last several years because of their lower cost, increased recyclability, and increasing consumer acceptance. Advancements in can-liner technology further support aluminum cans as a realistic option for wineries; however, data on how different packaging types influence the quality of packaged wine remains sparse. This study evaluated the physiochemical properties of carbonated blueberry wine stored in glass bottles, aluminum cans, and polyethylene terephthalate (PET) bottles under accelerated conditions (35 °C). Across the three packaging types, the wine quality parameters of total acidity, sugar, and pH did not differ significantly. There were, however, measurable statistical differences that emerged in color, anthocyanin content, and volatile organic compound (VOC) profiles. Pearson’s correlation analysis revealed a strong linear relationship between the degradation of color (intensity and hue) and anthocyanin concentration over time for all packaging types, with the loss being dependent upon packaging type. These findings indicate that while certain quality attributes vary with container, the overall chemical changes in blueberry wine are comparable across glass, aluminum, and PET bottles. Consequently, aluminum can packaging stands as a viable, cost-effective alternative packaging for blueberry wine producers. Full article

Vehicle emission inventories are highly sensitive to vehicle activity data, yet annual vehicle kilometers traveled (VKT) is still commonly represented using generalized default values whose representativeness at the city scale remains uncertain. In this study, large-scale vehicle inspection data from Haikou, China, were used to derive inspection-based VKT estimates and to quantify how activity assumptions affect urban vehicle emission inventories and policy evaluation. By holding vehicle population and emission factors constant across scenarios, we explicitly isolated the effect of activity representation on emission estimates. An inspection-based, age-sensitive VKT framework was further developed to capture within-fleet heterogeneity. The results showed that inspection-derived VKT accounted for only 36–75% of guideline-recommended values across major vehicle categories, with the largest discrepancies observed for diesel freight vehicles. As a result, the use of guideline-based VKT produced higher emission estimates by 34–39% for carbon monoxide (CO) and volatile organic compounds (VOCs) and by approximately 66–67% for nitrogen oxides (NOx) and particulate matter (PM). The influence of activity representation was also evident in policy assessment. In a case study of old diesel vehicle retirement, guideline-based VKT produced estimated emission reduction benefits that were more than 120% higher for most pollutants and nearly 200% higher for NOx than those derived from inspection-based VKT. These findings demonstrate that generalized activity assumptions can substantially affect both emission inventory estimates and policy-oriented assessments. Rather than merely refining a local mileage parameter, this study highlights a potential representativeness limitation of generalized activity assumptions when they are applied to city-specific emission inventories, particularly in medium-sized or geographically constrained urban systems. The inspection-based, age-sensitive approach proposed here provides a practical pathway for improving activity representation in data-rich urban environments, while its transferability should be evaluated according to local fleet structure and transport conditions. Full article

Volatile organic compounds (VOCs) have garnered substantial research interest in recent years due to their biodegradability, low toxicity, and potent antimicrobial properties against various plant pathogens. As a typical herbivore-induced plant volatile (HIPV) elicited by Nilaparvata lugens (Brown planthopper, BPH), (E)-2-hexenal has been identified as a promising natural antimicrobial agent. In this study, we investigated the protective potential of (E)-2-hexenal against Rhizoctonia solani (R. solani) in rice, focusing on both its direct antifungal activity and host-mediated defense mechanisms. In vitro antifungal assays demonstrated that treatment with 100 μL/mL (E)-2-hexenal resulted in a 91.07% inhibition of R. solani mycelial growth after 48 h. Scanning electron microscopy (SEM) observation and chitinase activity analysis revealed that (E)-2-hexenal suppressed fungal growth by disrupting the structural integrity of the pathogen cell wall. Furthermore, 100 μL/mL (E)-2-hexenal effectively conferred protection to detached rice leaves. Whole-plant inoculation assays confirmed that (E)-2-hexenal pretreatment significantly alleviated disease symptoms and triggered systemic resistance in rice plants. Physiological and biochemical analyses showed that (E)-2-hexenal treatment enhanced the activities of defense-related enzymes, elevated hydrogen peroxide (H₂O₂) levels, and promoted the accumulation of defensive metabolites in rice leaves. HPLC-MS quantification further revealed significant increases in the endogenous levels of jasmonic acid (JA) and salicylic acid (SA). Transcriptomic KEGG pathway enrichment analysis indicated that differentially expressed genes (DEGs) were mainly involved in alpha-linolenic acid metabolism, diterpenoid biosynthesis, phenylpropanoid biosynthesis, plant–pathogen interaction, and plant hormone signal transduction. Collectively, these results suggest that (E)-2-hexenal enhances rice resistance to sheath blight disease via a dual-action mechanism: direct inhibition of fungal development and activation of host immune responses. Our findings highlight the potential application of (E)-2-hexenal and other VOCs in developing eco-friendly strategies for sustainable rice disease management. Full article

Clinical monitoring of chronic liver disease (CLD) is currently hindered by the invasiveness of conventional biopsies. While breath-borne volatile organic compound (VOC) analysis offers a promising non-invasive alternative, the metabolic profiles of sedentary populations often overlap significantly with those of healthy individuals, making latent pathologies difficult to identify. To overcome this high-resolution diagnostic challenge, this study developed an integrated framework that couples high-performance semiconductor sensing technology with a machine learning-based analytical baseline. During the biomarker screening phase, GC-MS was utilized to analyze over 2000 VOCs, identifying 20 markers associated with CLD. These were further optimized into a robust feature panel including ammonia, isoprene, dimethyl sulfide (DMS), and limonene. For several critical metabolic features exhibiting high diagnostic potential, preliminary identifications were conducted by referencing NIST database matches and relevant literature. To maintain analytical rigor and account for the inherent complexity of trace volatile metabolites in biological samples, these signals are treated as putative metabolic features and characterized by their retention times. Regarding hardware, an InN-based sensor with Pt-AlN surface modification was fabricated, achieving a limit of detection (LOD) for ammonia below 0.2 ppm. Crucially, while the InN sensor was validated for specific core markers such as ammonia, the current AI classification model is trained on a refined 7-VOC panel derived from the comprehensive GC-MS data. To resolve diagnostic overlaps, a three-state dynamic sampling protocol (resting, exercise, and recovery) was implemented to isolate biomarkers that remain physiologically stable. By integrating multi-dimensional VOC features (e.g., isoprene and DMS) with sensor-validated data through DBSCAN and Random Forest algorithms, the framework successfully captured non-linear metabolic fingerprints. Machine learning results confirm that the framework effectively distinguished sedentary controls from CLD patients, achieving a macro-average AUC of 0.96. This integration provides a high-precision technical pathway for early-stage liver disease screening. Full article

Oil paintings, sketches, and printed works on paper frequently exhibit characteristic forms of deterioration caused by the absorption of linseed oil binders into the paper substrate. This study investigates for the first time the factors influencing the resulting volatile organic compound (VOC) emissions from oil-impregnated papers upon ageing and explores VOC quantifiable metrics suitable for condition assessment. Headspace Solid-Phase Microextraction coupled with Gas Chromatography-Mass Spectrometry (HS-SPME–GC-MS) was employed to sample and analyse VOCs from mock-ups made of three types of paper (a pure cellulosic, lignin-free and lignin-containing lignocellulosic papers with alkaline buffer), three pure linseed oil formulations (cold-pressed and alkaline-refined linseed oil, and stand oil), and oil-impregnated paper mock-ups, all subjected to controlled artificial ageing. The results showed a clear difference in VOC profile emissions between pure papers and linseed oil formulations, while oil-impregnated mock-ups emitted compounds matching those of the linseed oil formulations; however, the emissions followed a different trend. Statistical analysis (PCA) demonstrated that both paper pulp content and oil formulation significantly influence VOC emission patterns, highlighting the compounds that produce higher and most characteristic emissions. Ratios of specific compounds—such as formic to acetic acid—showed consistent trends across materials, indicating their potential as markers for distinguishing stages of deterioration. Full article

Prostate cancer (PCa) is one of the leading causes of cancer-related morbidity and mortality in men worldwide, and early detection remains crucial for ensuring effective treatment and improving patient outcomes. In this context, the development of non-invasive, accurate, and cost-effective screening strategies is of paramount importance. One particularly promising and innovative approach is the analysis of volatile organic compounds (VOCs), a field known as volatolomics. VOCs, which are metabolic by products released by the body, reflect underlying biochemical processes and offer a valuable, non-invasive source of diagnostic information. Recent advances have highlighted the potential of VOC profiling in PCa detection. A variety of biological systems have demonstrated remarkable sensitivity and specificity in recognizing disease-associated VOC signatures. Notably, trained dogs, selected invertebrates, and artificial sensing platforms have all shown the ability to identify PCa-related olfactory patterns. Among technological approaches, electronic noses (eNoses), which combine chemical sensor arrays with pattern recognition algorithms such as neural networks, represent a rapidly evolving diagnostic tool. Together, these biologically inspired and technology-driven strategies are reshaping the landscape of cancer diagnostics. They offer a compelling foundation for the development of rapid, non-invasive, and clinically translatable methods for PCa detection. This narrative review summarizes recent advances in using VOCs for PCa diagnosis and evaluates the reproducibility and clinical robustness of these approaches, focusing on challenges such as standardizing sampling, storage, and analysis, small cohort sizes, and the need for external validation and regulatory integration. Full article

The combustion of candles is known to emit various air pollutants, including particulate matter (PM) and volatile organic compounds (VOCs), into the air. This study characterizes emissions of these pollutants from natural and synthetic candles in a standard, sealed, unventilated residential environment. In addition, computational fluid dynamics (CFD) modeling was used to study the potential effects of inlet air velocity on a paraffin candle flame. A laminar diffusion flame model simulated the distributions of temperature, CO₂, and H₂O. A Testo DiSC mini air sampler was used for ultrafine particles and Lung-Deposited Surface Area (LDSA) data collection, and a CEM DT-9881 sampler was used for recording larger particle number concentrations, temperature, and relative humidity. VOC sorbent tubes were used for the collection of individual and total VOCs. Study findings showed that natural candles produced significantly (p < 0.05) higher LDSA ranges (mean 195.2 µm²/cm³) and ultrafine particle concentrations (mean 8.4 × 10¹¹ No/m³), while paraffin wax synthetic candles exhibited higher 0.3–10 µm PM concentrations (mean 2.0 × 10⁷ No/m³). CFD modeling showed that increasing air velocity produced a shorter, more compact flame and reduced CO₂ and H₂O mass fractions due to enhanced mixing and aerodynamic dilution, highlighting the strong interaction between airflow, temperature, and product formation in laminar paraffin flames. Full article

Industrial control of volatile organic compound (VOC) emissions from medium-density fibreboard (MDF) production remains constrained by a shortage of compound-resolved evidence from full-scale plants, where wood furnish, amino resin chemistry, heat transfer, gas flow, and wet gas cleaning act simultaneously. Here, we analysed more than 20,000 synchronized operating records from a full-scale single-stage flash-tube MDF dryer at an industrial SWISS KRONO production line and linked total VOC (TVOC) measurements from flame ionization detection with Fourier-transform infrared speciation on the cleaned stack. Five compounds—α-pinene, 3-carene, limonene, methanol, and formaldehyde—accounted for more than 80% of the resolved VOC signal. Process–state contrasts showed that higher digester residence time, discharge screw speed, adhesive amount, urea amount, dryer inlet temperature, and scrubber–water temperature increased one or more representative compounds, whereas higher hardwood share, additional flue-gas supply, and higher scrubber–water pH decreased them. Limonene, methanol, and formaldehyde were substantially more process-sensitive than α-pinene. An exploratory decorrelation step further showed that a drying/throughput domain explained about half of the variability of the screened process space. The study therefore identifies the small set of compounds and operating domains that most strongly govern the cleaned dryer-stack signature and provides a mechanistically grounded prioritization framework for follow-up causal experiments, source apportionment, and emission-mitigation design in industrial MDF manufacture. Unlike product or chamber emission studies, this work links the compound-resolved FTIR/FID chemistry of the final cleaned industrial stack with synchronized production variables; it therefore addresses a scale-integration gap by transforming routine compliance-type exhaust monitoring into a process-diagnostic framework for ranking emission sources, abatement-sensitive variables, and mitigation experiments. Full article

This study focuses on the application of photocatalysis for air pollution, targeting both chemical and biological contaminants. The selected target compounds were 3-methylbutan-1-ol (C₅H₁₂O), a volatile organic compound abundantly generated in the food industry, and Escherichia coli, representing a relevant bacterial indicator commonly encountered in such industrial environments and effectively embodying a biological threat. In this work, a series of experiments was conducted in a batch reactor using a novel TiO₂-based photocatalytic system integrating metal wires, namely copper (Cu) and silver (Ag), woven into an optical fiber support. A comparative evaluation of photocatalytic performance across different media was carried out for the removal of 3-methylbutan-1-ol, as well as for E. coli deactivation. The results demonstrated notable performance of the TiO₂-Cu medium for chemical treatment, achieving 97% removal efficiency after 85 min at an inlet concentration of 28 mg·m⁻³. Similarly, significant antibacterial activity was observed with 5.50 log reduction in colony-forming units (CFU) after 2.5 h. The photocatalytic performance of TiO₂-Cu supports was further validated under different operating conditions, including relative humidity levels ranging from 20% to 60% and concentration range from 5–30 mg·m⁻³. Finally, this study also includes a comparison between the TiO₂-Cu support and conventional photocatalytic systems based on TiO₂, particularly for simultaneous (combined) treatment of chemical and biological contaminants, with promising and encouraging outcomes. Full article

The efficiency with which solanaceous crops are pollinated is determined by pollinator behavioral preferences. Although Bombus terrestris typically outperforms Apis mellifera in this respect, the chemo-ecological mechanisms underlying their divergent olfactory responses remain insufficiently determined. We combined behavioral assays, gas chromatography–mass spectrometry, and electroantennogram recordings to compare the responses of these bee species to the volatile organic compounds (VOCs) emitted by tomato, pepper, and eggplant flowers. Whereas B. terrestris showed a strong foraging preference for all three crop plants, A. mellifera displayed distinct avoidance. Chemical analyses identified 82, 63, and 60 VOCs in tomato, pepper, and eggplant flowers, respectively. Among the 14 VOCs commonly emitted by all three crops, linalool, nerol, (E,E)-2,4-decadienal, 2-hexenal, tridecanal, and (E,Z)-2,6-nonadienal elicited significantly different electrophysiological responses in the two bee species, and are, thus, considered key compounds mediating their behavioral differences. Moreover, in behavioral assays, A. mellifera and B. terrestris showed significantly different responses to four concentration levels of linalool, nerol, (E,E)-2,4-decadienal, and tridecanal. This study elucidates the plant–pollinator olfactory interactions that contribute to determining the different foraging behaviors of two bee species in pollinating solanaceous crops, thereby providing a theoretical basis for optimizing pollinator attraction strategies. Full article

Uncontrolled scrap tire fires represent high-intensity episodic emission events that pose severe toxicological threats to urban environments. This study employs atmospheric dispersion modelling to quantify the impact of a tire stockpile fire on a distal educational receptor, evaluating two distinct dynamic stages of the event: an initial high-intensity open flame scenario (E1, 4 h) and a prolonged smouldering/suppression scenario (E2, 6 h), induced by firefighting interventions. Results reveal extreme pollutant loading at the receptor site during E1, with PM₁₀ and SO₂ concentrations peaking at 23,766 ${\displaystyle \frac{\mathsf{\mu }\mathrm{g}}{{\mathrm{m}}^3}}$ and 7821 ${\displaystyle \frac{\mathsf{\mu }\mathrm{g}}{{\mathrm{m}}^3}}$ respectively, indicating an immediate risk of acute respiratory distress. The organic fraction was dominated by volatile organic compounds (VOCs) (8691 ${\displaystyle \frac{\mathsf{\mu }\mathrm{g}}{{\mathrm{m}}^3}}$) and a ∑16 PAHs flux of 313.9 ${\displaystyle \frac{\mathsf{\mu }\mathrm{g}}{{\mathrm{m}}^3}}$. Toxicological assessment identified Benzo[a]pyrene (BaP) as the primary driver of health hazards, contributing approximately 70% to the carcinogenic risk profile. A critical disparity was observed between Mutagenic Equivalency (MEQ) of 18.32 and Toxic Equivalency (TEQ) of 15.37, suggesting that standard monitoring significantly underestimates the biological threat to sensitive paediatric populations. These findings demonstrate that acute, oxygen-limited tire combustion creates a concentrated toxic slug of high-molecular-weight PAHs. The study underscores the necessity of integrating mutagenicity-based models into emergency response protocols to accurately safeguard vulnerable communities against the long-term toxicological legacy of elastomer thermolysis. Full article

The ecological interaction between plants and herbivores has promoted the evolution of defense and offense characteristics of both parties. Specialized metabolites, including volatile organic compounds (VOCs), constitute a key defensive mechanism of plants, helping to reduce/prevent damage by herbivores and indirectly attracting their natural enemies. However, in the absence of herbivores, as occurs in invaded ranges, natural selection may favor the reduction in costly chemical defenses. Here, we assessed the production of VOCs in both damaged and undamaged leaves of plants of Datura stramonium from Mexico (native) and Spain (non-native). The emissions of VOCs were detected and compared, along with the induction extended to neighboring undamaged leaves. A total of 45 VOCs were detected and differences in chemical diversity and concentration between plants of different origin and between damaged and undamaged leaves. Notably, native populations exhibited greater VOCs diversity and higher emission levels than non-native populations, highlighting population-specific differences in both constitutive and induced chemical defenses. Expression analysis of the gene implicated in terpenoid biosynthesis (DsTPS10) demonstrated damage-induced upregulation. Gene expression patterns coupled with metabolic profiles suggest a potential defense capability of native populations as compared with non-native populations of recent evolution in the absence of the D. stramonium’s coevolved herbivores. Full article

Food-deceptive orchids exhibit significant phenotypic variability in floral traits. However, the diversity of their floral low-volatility and volatile organic compounds (VOCs) remains poorly understood. This study investigated floral diversity in the orchid Anacamptis longicornu across six Sardinian populations to evaluate the influence of environmental factors and colour polymorphism on low-volatility and volatile profiles. Chemical profiles of flower extracts obtained through steam distillation followed by liquid–liquid extraction were characterized using GC/MS analysis. A total of 79 compounds were identified, primarily saturated and unsaturated hydrocarbons, alcohols, ketones, aldehydes, esters, mono- and sesquiterpenes. Dominant compounds across both violet and white morphs included nonadecane, eicosane, octadecane, henicosane, and docosane. Significant chemical variability was detected among populations and between colour morphs, indicating that colour polymorphism substantially shapes floral profiles. Environmental heterogeneity also emerged as a critical driver, with populations exposed to extreme conditions exhibiting increased chemical diversity. Furthermore, greater geographical distance among populations correlated with higher dissimilarity in floral profiles. This study provides the first comprehensive characterization of floral diversity in A. longicornu, confirming that phenotypic variability extends to chemical traits in food-deceptive orchids. Our results highlight that the diversification in food-deceptive orchids arises from a combination of biotic and abiotic drivers. Full article