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Health, environmental and ethical concerns have resulted in a dramatic increase in demand for plant-based dairy analogues. While the volatile organic compounds (VOCs) responsible for the characteristic flavours of dairy-based products have been extensively studied, little is known about how to reproduce such flavours using only plant-based substrates. As a first step in their development, this review provides an overview of the VOCs associated with fermented (bacteria and/or fungi/yeast) vegetable and fruit substrates. Following PRISMA guidelines and using two English databases (Web of Science and Scopus), thirty-five suitable research papers were identified. The number of fermentation-derived VOCs detected ranged from 32 to 118 (across 30 papers), while 5 papers detected fewer (10 to 25). Bacteria, including lactic acid bacteria (LAB), fungi, and yeast were the micro-organisms used, with LAB being the most commonly reported. Ten studies used a single species, 21 studies used a single type (bacteria, fungi or yeast) of micro-organisms and four studies used mixed fermentation. The nature of the fermentation-derived VOCs detected (alcohols, aldehydes, esters, ketones, acids, terpenes and norisoprenoids, phenols, furans, sulphur compounds, alkenes, alkanes, and benzene derivatives) was dependent on the composition of the vegetable/fruit matrix, the micro-organisms involved, and the fermentation conditions. [ABSTRACT FROM AUTHOR]

The Bacillus velezensis GJ-7 strain isolated from the rhizosphere soil of Panax notoginseng showed high nematicidal activity and therefore has been considered a biological control agent that could act against the root-knot nematode Meloidogyne hapla. However, little was known about whether the GJ-7 strain could produce volatile organic compounds (VOCs) that were effective in biocontrol against M. hapla. In this study, we evaluated the nematicidal activity of VOCs produced by the fermentation of GJ-7 in three-compartment Petri dishes. The results revealed that the mortality rates of M. hapla J2s were 85% at 24 h and 97.1% at 48 h after treatment with the VOCs produced during GJ-7 fermentation. Subsequently, the VOCs produced by the GJ-7 strain were identified through solid-phase micro-extraction gas chromatography mass spectrometry (SPME-GC/MS). Six characteristic VOCs from the GJ-7 strain fermentation broth were identified, including 3-methyl-1-butanol, 3-methyl-2-pentanone, 5-methyl-2-hexanone, 2-heptanone, 2,5-dimethylpyrazine, and 6-methyl-2-heptanone. The in vitro experimental results from 24-well culture plates showed that the six volatiles had direct-contact nematicidal activity against M. hapla J2s and inhibition activity against egg hatching. In addition, 3-methyl-1-butanol and 2-heptanone showed significant fumigation effects on M. hapla J2s and eggs. Furthermore, all six of the VOCs repelled M. hapla J2 juveniles in 2% water agar Petri plates. The above data suggested that the VOCs of B. velezensis GJ-7 acted against M. hapla through multiple prevention and control modes (including direct-contact nematicidal activity, fumigant activity, and repellent activity), and therefore could be considered as potential biocontrol agents against root-knot nematodes. [ABSTRACT FROM AUTHOR]

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Beijing's industrial structure is changing rapidly, and many small and dispersed businesses are becoming major contributors of VOC emissions. There are about 740 auto parts enterprises in Beijing, and is typical of a small industry in which VOC emissions cannot be ignored. Two typical water-based paint auto parts electrophoresis enterprises in Beijing were selected in this study. The results show that the annual average VOC emissions of both enterprises were 3.72 t, while the unorganized emissions accounted for 36.2%. The analysis of VOC emissions characteristics in the exhausts revealed that oxygenated VOCs (OVOCs) (acetone, 2-butanone, ethyl acetate, etc.) were the most abundant components (~ 21.88–68.66%), followed by alkanes (~ 6.93–25.34%), and olefins (~ 2.67–50.44%). The concentrations of VOCs (ρ(VOCs)) from drying chimney were 8.941 mg/m3, while the electrophoresis process accounted for 0.792 mg/m3. The comparison of the effects of VOCs treatment facilities demonstrated that regenerative thermal oxidizer and thermal oxidizer increased the VOC concentration instead of decreased, due to a large amount of gas supplemented. The activated carbon adsorption was ineffective in treating non-polar VOCs such as alkanes, while the neutralizing absorption was relatively stable. In addition, the ozone formation potential and health risk assessments (cancer and non-cancer risks) show that water-based enterprises are still partially at risk. Based on the emission characteristics of VOCs and the technical feasibility, it is recommended to improve the collection rate of disorganized exhaust gas from electrophoresis workshop, adjust the values of emission standards, and optimize the end treatment measures of the drying workshop. [ABSTRACT FROM AUTHOR]

The established efficacy of electronic volatile organic compound (VOC) detection technologies as diagnostic tools for noninvasive early detection of COVID-19 and related coronaviruses has been demonstrated from multiple studies using a variety of experimental and commercial electronic devices capable of detecting precise mixtures of VOC emissions in human breath. The activities of numerous global research teams, developing novel electronic-nose (e-nose) devices and diagnostic methods, have generated empirical laboratory and clinical trial test results based on the detection of different types of host VOC-biomarker metabolites from specific chemical classes. COVID-19-specific volatile biomarkers are derived from disease-induced changes in host metabolic pathways by SARS-CoV-2 viral pathogenesis. The unique mechanisms proposed from recent researchers to explain how COVID-19 causes damage to multiple organ systems throughout the body are associated with unique symptom combinations, cytokine storms and physiological cascades that disrupt normal biochemical processes through gene dysregulation to generate disease-specific VOC metabolites targeted for e-nose detection. This paper reviewed recent methods and applications of e-nose and related VOC-detection devices for early, noninvasive diagnosis of SARS-CoV-2 infections. In addition, metabolomic (quantitative) COVID-19 disease-specific chemical biomarkers, consisting of host-derived VOCs identified from exhaled breath of patients, were summarized as possible sources of volatile metabolic biomarkers useful for confirming and supporting e-nose diagnoses. [ABSTRACT FROM AUTHOR]

Microdroplets have many unique features derived from the large surface-volume ratio and the ultrahigh electric field at the air-water interface, therefore they can remarkably accelerate various slow reactions and trigger reactions that won’t occur in bulk solutions. The size of atmospheric aerosols is similar to that of the microdroplets, so reactions performed in microdroplets and ambient conditions can act as good simulations of important atmospheric processes, which will provide a better understanding of the role of aerosols. Aldehydes are important oxidized species in the atmosphere derived from releases of human activities, such as vehicle emissions and biomass burning, which can generate volatile organic compounds (VOCs) and are highly related to salt-rich aerosol formation through further oxidation. Studying of aldehydes’ hydration and oxidation reactions is very helpful for understanding the complex conversion process from VOCs to secondary organic aerosols (SOA). In this work, several aromatic aldehydes with different electron donating or withdrawing groups were studied by spraying their solutions into microdroplets, then directly characterizing them by online mass spectrometry. It showed that these aromatic aldehydes could be oxidized into carboxylic acids under the space-restricting condition of microdroplets, and the hydration reactions of aromatic aldehydes could be induced by carboxylate under the extreme pH environment and abundant reactive oxygen species provided by the air-water interface of microdroplets. Together, the products of oxidation and hydration reactions would combine to yield relatively unstable “carboxylate-aldehyde hydrate” complex ions. The lifetime of the ions was roughly estimated by conducting a collision-induced disassociation (CID) experiment and comparing it to the instrument running procedure, and the structure was checked using CID and a cross-forming reaction between two different aldehydes. This work revealed that the complex ions were potential intermediates of the atmospheric aldehyde oxidation reaction, providing a previously unknown pathway of atmospheric carboxylic acids and SOA. This result supported the view that atmospheric oxidation might take place in aerosols, such as fog and clouds, which was the missing part of SOA sources and matched the observations. However, unlike other liquid phase or gaseous simulation research of the oxidation process of aldehydes, the oxidation reaction would occur even without the participation of UVs or hydrogen peroxide addition in microdroplets, because the air-water interface could generate a large number of reactive oxygen species (ROS) like hydroxyl radicals and hydrogen peroxide, implicating that the air-water interface of aerosols might be an important place to perform many atmospheric reactions. [ABSTRACT FROM AUTHOR]

The emission characteristics of VOCs (volatile organic compounds) from laminate flooring were investigated and their impacts on indoor environment evaluated in order to provide basic data for the study of harmful gas release from laminate flooring, and to provide reference for producers and consumers to evaluate their effects on indoor air quality. In this study, Shuang Xiang laminate flooring was selected and sampled with 1 m 3 climate chamber method. The sampled VOCs were analyzed by GC-MS (gas chromatography-mass spectrometry) and according to the forestry industry standards LY/ T 3230-2020 “Classification of volatile organic compound emissions contents from wood-made panels and their finishing products” and LY/ T 3229 - 2020 “ Specification for indoor carrying capacity of wood-based panels and finishing products based on volatile organic compounds emission”, the laminate flooring on indoor air quality was evaluated. Results showed that the TVOC release of this laminate flooring gradually decreased with time and reached the release equilibrium at day 28. The VOCs released were mainly olefins, aromatic hydrocarbons and alkanes, with small amounts of aldehydes, ketones, lipids and alcohols. In one cycle, the release level of naphthalene on the 3rd day of the laminate flooring did not meet the Class I standard, and the release levels of several major pollutants were Class I at the rest of the time. VOCs composite index of laminate flooring decreased with the increase of time after the 3rd day, and according to the composite index grading standard, the VOCs release class of laminate flooring on the 3rd day was Class Ⅱ, and the indoor air quality was qualified, and the VOCs release class of the rest of the time was Class I, and the indoor air quality was excellent. The TVOC release rate of this laminate flooring gradually decreased with time, in line with the mass transfer principle. After the VOCs were released in equilibrium, the release class is in line with Class I. The calculated composite index was in line with Class I. The indoor air quality was excellent and consumers can use it with confidence [ABSTRACT FROM AUTHOR]

Polymeric materials are widely employed for monitoring volatile organic compounds (VOCs). Compared to other sensitive materials, polymers can provide a certain degree of selectivity, based on their chemical affinity with organic solvents. The addition of conductive nanoparticles within the polymer layer is a common practice in recent years to improve the sensitivity of these materials. However, it is still unclear the effect that the nanoparticles have on the selectivity of the polymer membrane and vice versa. The current work proposes a methodology based on the Hansen solubility parameters, for assessing the selectivity of both pristine and hybrid polymer nanocomposites. The impedance response of thin polydimethylsiloxane (PDMS) films is compared to the response of hybrid polymer films, based on the addition of multi‐walled carbon nanotubes (MWCNTs). With the addition of just 1 wt.% of MWCNTs, fabricated sensors showcased a significant improvement in sensitivity, faster response times, as well as enhanced classification of non‐polar analytes (>22% increase) compared to single PDMS layers. The methodology proposed in this work can be employed in the future to assess and predict the selectivity of polymers in single or array‐based gas sensors, microfluidic channels, and other analytical devices for the purpose of VOCs discrimination. [ABSTRACT FROM AUTHOR]

The demand for a wide choice of food that is safe and palatable increases every day. Consumers do not accept off-flavors that have atypical odors resulting from internal deterioration or contamination by substances alien to the food. Odor response depends on the volatile organic compounds (VOCs), and their detection can provide information about food quality. Gas chromatography/mass spectrometry is the most powerful method available for the detection of VOC. However, it is laborious, costly, and requires the presence of a trained operator. To develop a faster analytic tool, we designed a non-Faradaic impedimetric biosensor for monitoring the presence of VOCs involved in food spoilage. The biosensor is based on the use of the pig odorant-binding protein (pOBP) as the molecular recognition element. We evaluated the affinity of pOBP for three different volatile organic compounds (1-octen-3-ol, trans-2-hexen-1-ol, and hexanal) related to food spoilage. We developed an electrochemical biosensor conducting impedimetric measurements in liquid and air samples. The impedance changes allowed us to detect each VOC sample at a minimum concentration of 0.1 μM. [ABSTRACT FROM AUTHOR]

The germplasms of the Murraya koenigii were collected from Rajahmundry, Annur, Kollihills, Suvashini, Bhavanisagar, Karamadai (KMM5, KMM6, KMM7, KMM8 and KMM14) and the Kerala Agricultural University (KAU). The fresh leaves were analyzed for its volatile organic compounds by Thermal Desorption Gas chromatography–Mass Spectroscopy (TD-GC-MS) to obtain germplasm specific volatile fingerprinting. The correlation between genotypes based on volatile profiles has been analyzed using principal component analysis (PCA) and hierarchical cluster analysis (HCA). A wide variety of volatile compounds identified in the eleven M. koenigii genotypes belongs to terpenoids, monoterpenes, sesquiterpenes, aldehyde, ketones, benzenes, azulenes and other minor compounds. The α-pinene and β-pinene content is high in Suvashini and Bhavanisagar (BSR) genotypes respectively. The monoterpenes such as γ-terpinene, α-myrcene and terpinolene are high in Karamadai variety (KMMK8), whereas caryophyllene content is high in the Rajahmundry. The results of PCA revealed that significant variances with 45.47% (PC 1) and 21.40% (PC 2). In AHC, the α-pinene and chloral hydrate forms the one major cluster. Additionally, α-fenchene and α-caryophyllene has observed forming second major cluster with significant magnitude. The cluster formed by sesquiterpenes are observed high in Annur (65.34%), followed by KMMK8 (48.01%), Kollihills (39.89%) and Rajahmundry (39.27%). The PCA and AHC combined with the fingerprint of TD-GC-MS have discriminated qualitative volatile profile and indicated that major changes VOCs emitted are highly attributed to the genetic factors.

Maternal milk is pivotal for infants’ nutrition. It also portrays the chemical burden to which the mother has been exposed. One of the chemical families that is prevalent and related to potential toxic effects are volatile organic compounds (VOCs). In the present study, motivated by the scarcity of works dealing with concomitant VOC and metabolite determination in maternal milk, two new gas/liquid chromatography tandem mass spectrometry (GC-MS/MS, LC-MS/MS) methods for the simultaneous measurement of 25 VOCs and 9 of their metabolites, respectively, in maternal milk were developed and applied to 20 maternal milk samples collected from mothers in Greece. In parallel, a headspace solid-phase microextraction (HS-SPME)–GC-MS method was employed for the untargeted screening of chemicals. Low detection rates for benzene, toluene, styrene and p,m-xylenes, and three of their metabolites, namely N-acetyl-S-(benzyl)-L-cysteine (BMA, metabolite of toluene), 3-methylhippuric (3-MHA, metabolite of xylenes) and mandelic acid (MA as DL and R isomers, metabolites of styrene and ethylbenzene), were evidenced in concentrations varying from −1. HS-SPME–GC-MS disclosed the presence of common maternal milk constituents such as fatty acids. Nevertheless, bisphenol-A, bisphenol derivatives and phthalates were also detected. The infants’ health risk assessment demonstrated a low risk and negligible carcinogenic risk, yet the detection of these compounds should not be underestimated.

Fermentation by lactic acid bacteria (LAB) is a promising approach to meet the increasing demand for meat or dairy plant-based analogues with realistic flavours. However, a detailed understanding of the impact of the substrate, fermentation conditions, and bacterial strains on the volatile organic compounds (VOCs) produced during fermentation is lacking. As a first step, the current study used a defined medium (DM) supplemented with the amino acids L-leucine (Leu), L-isoleucine (Ile), L-phenylalanine (Phe), L-threonine (Thr), L-methionine (Met), or L-glutamic acid (Glu) separately or combined to determine their impact on the VOCs produced by Levilactobacillus brevis WLP672 (LB672). VOCs were measured using headspace solid-phase microextraction (HS-SPME) gas chromatography–mass spectrometry (GC-MS). VOCs associated with the specific amino acids added included: benzaldehyde, phenylethyl alcohol, and benzyl alcohol with added Phe; methanethiol, methional, and dimethyl disulphide with added Met; 3-methyl butanol with added Leu; and 2-methyl butanol with added Ile. This research demonstrated that fermentation by LB672 of a DM supplemented with different amino acids separately or combined resulted in the formation of a range of dairy- and meat-related VOCs and provides information on how plant-based fermentations could be manipulated to generate desirable flavours.

The leakage of gases and chemical vapors is a common accident in laboratory processes that requires a rapid response to avoid harmful effects if humans and instruments are exposed to this leakage. In this paper, the performance of a portable sensor node designed for integration with mobile and stationary robots used to transport chemical samples in automated laboratories was tested and evaluated. The sensor node has four main layers for executing several functions, such as power management, control and data preprocessing, sensing gases and environmental parameters, and communication and data transmission. The responses of three metal oxide semiconductor sensors, BME680, ENS160, and SGP41, integrated into the sensing layer have been recorded for various volumes of selected chemicals and volatile organic compounds, including ammonia, pentane, tetrahydrofuran, butanol, phenol, xylene, benzene, ethanol, methanol, acetone, toluene, and isopropanol. For mobile applications, the sensor node was attached to a sample holder on a mobile robot (ASTI ProBOT L). In addition, the sensor nodes were positioned close to automation systems, including stationary robots. The experimental results revealed that the tested sensors have a different response to the tested volumes and can be used efficiently for hazardous gas leakage detection and monitoring.

Enhanced ozone (O3) pollution has emerged as a pressing environmental concern in China, particularly for densely populated megacities and major city clusters. However, volatile organic compounds (VOCs), the key precursors to O3 formation, have not been routinely measured. In this study, we characterize the spatial and temporal patterns of VOCs and examine the role of VOCs in O3 production in five cities (Dongying (DY), Rizhao (RZ), Yantai (YT), Weihai (WH), and Jinan (JN)) in the North China Plain (NCP) for two sampling periods (June and December) in 2021 through continuous field observations. Among various VOC categories, alkanes accounted for the largest proportion of VOCs in the cities. For VOCs, chemical reactivities, aromatic hydrocarbons, and alkenes were dominant contributors to O3 formation potential (OFP). Unlike inland regions, the contribution to OFP from OVOCs increased greatly at high O3 concentrations in coastal regions (especially YT). Model simulations during the O3 episode show that the net O3 production rates were 27.87, 10.24, and 10.37 ppbv/h in DY, RZ, and JN. The pathway of HO2 + NO contributed the most to O3 production in JN and RZ, while RO2 + NO was the largest contributor to O3 production in DY. The relative incremental reactivity (RIR) revealed that O3 formation in DY was the transitional regime, while it was markedly the VOC-limited regime in JN and RZ. The O3 production response is influenced by NOx concentration and has a clear daily variation pattern (the sensitivity is greater from 15:00 to 17:00). The most efficiencies in O3 reduction could be achieved by reducing NOx when the NOx concentration is low (less than 20 ppbv in this study). This study reveals the importance of ambient VOCs in O3 production over the NCP and demonstrates that a better grasp of VOC sources and profiles is critical for in-depth O3 regulation in the NCP.

X-ray irradiation is an emerging non-thermal technology that is used as a preservation and sanitization technique to inactivate pathogens and spoilage organisms, increasing the shelf life of products. In this work, two different types of surface-ripened cheeses, Brie and Camembert, produced with cow milk, were treated with X-rays at three dose levels, 2.0, 4.0 and 6.0 kGy, to evaluate the irradiation effects on the volatile profile using a volatolomic approach. The headspace solid-phase microextraction (HS-SPME) technique combined with gas chromatography–mass spectrometry (GC–MS) was used to extract and analyze the volatile fraction from these dairy matrices. The HS-SPME method was optimized by a central composite design in combination with a desirability optimization methodology. The Carboxen/PDMS fiber, 50 °C for extraction temperature and 60 min for time extraction were found to be the best parameter settings and were applied for this investigation. The obtained fingerprints demonstrated that the irradiation-induced changes are dose dependent. The X-ray irradiation produced many new volatiles not found in the non-irradiated samples, but it also varied the amount of some volatiles already present in the control. Specifically, aldehydes and hydrocarbons increased with the irradiation dose, whereas alcohols, carboxylic acids, esters, methyl esters, ketones, lactones and sulfur-containing compounds showed a non-linear dependence on the dose levels; indeed, they increased up to 4.0 kGy, and then decreased slightly at 6.0 kGy. This trend, more evident in the Camembert profile, is probably due to the fact that these compounds are involved in different oxidation mechanisms of lipids and proteins, which were induced by the radiation treatment. In these oxidative chemical changes, the production and degradation processes of the volatiles are competitive, but at higher doses, the decomposition reactions exceed those of formation. A principal component analysis and partial least square discriminant analysis were used to discriminate between the treated and untreated samples. Moreover, this study allowed for the identification of potential markers of X-ray treatment for the two cheeses, confirming this approach as a useful tool for the control of irradiated surface-ripened cheeses.

Volatile organic compounds (VOCs) with a large chemical diversity are emitted by plant flowers. These compounds play an important role in the ecology of plants. This review presents the different ecological roles of VOCs present in the odor plumes of plant flowers, such as pollination, defense, adaptation to their environment, and communication with other organisms. The production and accumulation sites of VOCs in plants with their spatial and temporal variations, including environmental issues, are also summarized. To evaluate the qualitative and quantitative chemical composition of VOCs, several methods of extraction and analysis were used. Headspace (HS) sampling coupled with solid phase microextraction (SPME) is now well-developed for the extraction process. Parameters are known, and several fibers are now available to optimize this extraction. Most of the time, SPME is coupled with gas chromatography-mass spectrometry (GC-MS) to determine the structural identification of the VOCs, paying attention to the use of several complementary methods for identification like the use of databases, retention indices, and, when available, comparison with authentic standards analyses. The development of the knowledge on VOCs emitted by flowers is of great importance for plant ecology in the context of environmental and climate changes.

Ready-to-eat kiwifruit has gained significant market value in recent years due to its convenience and the increasing consumer demand for healthy ready-to-eat snacks. The volatile compound content (VOC) in ready-to-eat kiwifruit is a crucial factor determining its flavor and aroma. VOC is an important characteristic that positively affects the overall evaluation of ready-to-eat kiwifruit. In this study, we utilized gas chromatography-ion mobility spectrometry (GC-IMS) to investigate changes in the composition of VOCs in ready-to-eat kiwifruit during different storage periods (every 12 h). Our results revealed the presence of 55 VOCs in ready-to-eat kiwifruit, with alcohols, esters, and ketones being the dominant compounds responsible for the aromatic flavor. Among these compounds, methyl caproate, ethyl butyrate, and ethyl propionate provided specific fruit flavors to ready-to-eat kiwifruit, whereas esters played a secondary role. Furthermore, varying trends were observed for different compound types as the storage period increased: alcohols exhibited a decreasing trend, whereas ester products and some sulfur-containing compounds showed an increase. Additionally, fingerprint profiles of volatile compounds were established for each storage period, enabling the identification of characteristic substances. This comprehensive analysis of volatile flavor substances during the ripening of ready-to-eat kiwifruit will greatly contribute to enhancing its sensory quality, consumer appeal, and overall marketability.

Applying plant-derived fungicides is a safe and sustainable way to control wheat scab. In this study, volatile organic compounds (VOCs) of wheat cultivars with and without the resistance gene Fhb1 were analyzed by GC-MS, and 2-phenylethanol was screened out. The biocontrol function of 2-phenylethanol on Fusarium graminearum was evaluated in vitro and in vivo. Metabolomics analysis indicated that 2-phenylethanol altered the amino acid pathways of F. graminearum, affecting its normal life activities. Under SEM and TEM observation, the mycelial morphology changed, and the integrity of the cell membrane was destroyed. Furthermore, 2-phenylethanol could inhibit the production of mycotoxins (DON, 3-ADON, 15-ADON) by F. graminearum and reduce grain contamination. This research provides new ideas for green prevention and control of wheat FHB in the field.

Lily is one of the most important cut flowers in the world, with a rich floral fragrance. To further explore the fragrance emission mechanisms of lily cultivars, headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS) and organic solvent extraction–gas chromatography–mass spectrometry (OSE-GC-MS) were used to unveil the volatile organic compounds (VOCs) and endogenous extracts of seven lily cultivars. Furthermore, real-time quantitative PCR (qRT-PCR) was used to determine the expression levels of two key genes (TPS and BSMT) related to the biosynthesis of monoterpenoids and methyl benzoate. The results show that forty-five VOCs were detected in the petals of seven lily cultivars, and the main compounds were monoterpenoids and phenylpropanoids/benzenoids. Dichloromethane was the best solvent for extracting the endogenous extracts of Lilium ‘Viviana’ petals and eighteen endogenous extracts were detected using dichloromethane to extract the petals of seven lily cultivars. Each compound’s emission ratio (natural logarithm of the ratio of VOC content to endogenous extract content) was calculated, and linear regression analyses between emission ratios and boiling points were conducted. Significant linear negative correlations existed between the emission ratios and boiling points of compounds, and the regression equations’ coefficients of determination (R2) were all greater than 0.7. TPS was expressed highly in ‘Viviana’, ‘Pink News’, and ‘Palazzo’, and BSMT was expressed highly in ‘Pink News’ and ‘Palazzo’. Correlation analyses between the gene expression levels and the monoterpenoids and methyl benzoate contents found that the TPS expression levels have strong positive correlations with monoterpenoids content, while no correlations were found between the expression levels of BSMT and the contents of methyl benzoate. This study lays the foundation for research on the release patterns of VOCs in the flowers of Lilium, and the breeding of lilies for their floral fragrance.

Starting around 2008, there was rapid expansion of oil and natural gas (ONG) production into more heavily populated areas within the Dallas-Fort Worth metroplex in the Barnett Shale region of Texas. This colocation raised concerns regarding the effect of ONG activities on chemical levels in the air. In the current study, we examined the potential impacts of ONG activity on the types and concentrations of chemicals in ambient air in the Barnett Shale. Volatile organic compound (VOC) concentrations from 6–12 years (2008–2019) of hourly ambient air monitoring data from 15 monitors (4 monitors had ≥ 10 years of data) were compared to several metrics of ONG activity (number of active wells, natural gas production, condensate production) within a 2-mile radius of each monitor. Monitoring sites were also classified into urban, suburban, and rural areas as a surrogate for nearby vehicular emission sources. Analyses of this huge dataset showed that both peak and mean chemical concentrations of lighter alkane hydrocarbons (e.g., ethane) were most impacted by the number of gas wells. Levels of heavier alkanes (e.g., pentane) were increased by condensate production and at monitors located in areas with greater urbanicity, and therefore higher vehicular emissions. The levels of unsaturated alkynes (e.g., ethylene) were entirely driven by urbanicity and were unaffected by nearby ONG activity. The same pattern was seen with the ratio of iso:n-pentane, which is contrary to the findings of others and suggests an area for future research. Aromatic hydrocarbons were impacted by multiple emissions sources and did not show the same patterns as non-aromatic VOCs. No VOC concentrations were at levels of concern for human health or odor based on comparison to Texas air monitoring comparison values. Overall, ONG activities impact air quality, but this must be evaluated in the context of other emission sources such as automobiles.

Introduction: Artificial turf or synthetic grass releases hazardous substances such as heavy metals, polycyclic aromatic hydrocarbons (PAHs), and volatile organic compounds (VOCs). Objective: The current study aimed to evaluate the concentration levels of hazardous substances that are emitted from artificial turf as a result of sunlight effect; and to assess the expected exposure risks to such emitted substances during various activities.The current study aimed to evaluate the concentration levels of hazardous substances that are emitted from artificial turf as a result of the effect of sunlight. And to assess the expected risks of exposure to these substances emitted during the various activities. Study design: VOCs emitted from artificial turf samples were monitored and collected in the ambient air of three football fields, the ambient air around a piece of new artificial turf that has not yet been used on playing fields, but has been exposed to sunlight within one year and in the indoor air around a piece of new artificial turf. Which has not yet been used on the playgrounds and was placed at room temperature and away from sunlight. Results: The current study shows that average afternoon morning VOCs levels were 277, 333, 405 and 509 mg/m3 in winter, autumn, spring and summer, respectively. The most predominant PAHs compounds present in the samples were compounds with 3-rings and 4-rings.The average daily intake (ADI) for three exposure routes (ingestion, inhalation, and dermal contact) was calculated for different age categories (3–6, 7–15, 16–18, 19–22, 23–55, and 56–70 year). Non-Carcinogenic exposure risk as hazard quotient (HQ) and hazard index (HI) were detected. Conclusion: All HI values were 3–6 years.

Abstract Polymeric materials are widely employed for monitoring volatile organic compounds (VOCs). Compared to other sensitive materials, polymers can provide a certain degree of selectivity, based on their chemical affinity with organic solvents. The addition of conductive nanoparticles within the polymer layer is a common practice in recent years to improve the sensitivity of these materials. However, it is still unclear the effect that the nanoparticles have on the selectivity of the polymer membrane and vice versa. The current work proposes a methodology based on the Hansen solubility parameters, for assessing the selectivity of both pristine and hybrid polymer nanocomposites. The impedance response of thin polydimethylsiloxane (PDMS) films is compared to the response of hybrid polymer films, based on the addition of multi‐walled carbon nanotubes (MWCNTs). With the addition of just 1 wt.% of MWCNTs, fabricated sensors showcased a significant improvement in sensitivity, faster response times, as well as enhanced classification of non‐polar analytes (>22% increase) compared to single PDMS layers. The methodology proposed in this work can be employed in the future to assess and predict the selectivity of polymers in single or array‐based gas sensors, microfluidic channels, and other analytical devices for the purpose of VOCs discrimination.

Introduction: There is a need to improve the diagnosis and management of pediatric asthma. Breath analysis aims to address this by non-invasively assessing altered metabolism and disease-associated processes. Our goal was to identify exhaled metabolic signatures that distinguish children with allergic asthma from healthy controls using secondary electrospray ionization high-resolution mass spectrometry (SESI/HRMS) in a cross-sectional observational study.Methods: Breath analysis was performed with SESI/HRMS. Significant differentially expressed mass-to-charge features in breath were extracted using the empirical Bayes moderated t-statistics test. Corresponding molecules were putatively annotated by tandem mass spectrometry database matching and pathway analysis.Results: 48 allergic asthmatics and 56 healthy controls were included in the study. Among 375 significant mass-to-charge features, 134 were putatively identified. Many of these could be grouped to metabolites of common pathways or chemical families. We found several pathways that are well-represented by the significant metabolites, for example, lysine degradation elevated and two arginine pathways downregulated in the asthmatic group. Assessing the ability of breath profiles to classify samples as asthmatic or healthy with supervised machine learning in a 10 times repeated 10-fold cross-validation revealed an area under the receiver operating characteristic curve of 0.83.Discussion: For the first time, a large number of breath-derived metabolites that discriminate children with allergic asthma from healthy controls were identified by online breath analysis. Many are linked to well-described metabolic pathways and chemical families involved in pathophysiological processes of asthma. Furthermore, a subset of these volatile organic compounds showed high potential for clinical diagnostic applications.

As the main consumed meat of Chinese residents, pork has a unique flavor, but the internal volatile organic compounds that cause the flavor differences between pork muscles are not clear at present. In this study, four muscles of Duroc × (Landrace × Yorkshire) pigs (loin, ham, shoulder and belly) were used as experimental subjects. Through the analysis of volatile organic compounds in four muscles of pork, the internal volatile organic compounds of different muscles of pork were discussed. Gas chromatography-ion mobility spectrometry was employed to analyze the four muscles, and volatile organic compounds in these muscles were analyzed and identified. A total of 65 volatile organic compound peaks were obtained by gas chromatography-ion mobility spectrometry. From the qualitative database, a total of 49 volatile organic compounds were identified, including aldehydes, alcohols and ketones. With the variable importance for the projection greater than 1 and significance level less than 0.05 as the criterion, the organic compounds with significant differences were screened by partial least squares-discriminant analysis and significance difference analysis. It was determined that 2-pentylfuran, 2-butanone (M), pentanal (M), butanal (D), (E)-2-hexenal, (E)-2-heptenal (D), 1,2-propanediol and 2-methylpropanal were the differential organic compounds that distinguish the four pork muscles. [ABSTRACT FROM AUTHOR]

Simple Summary: Volatile organic compounds (VOCs) in urine headspace have been previously shown to be potential biomarkers for prostate cancer. The aim of the current study is to further evaluate urinary VOCs as biomarkers in humans, assess their ability to stratify aggressive tumors, and compare them to the results of murine models of induced prostate cancer. Chemometric analyses were implemented and showed that VOCs in mouse urine were highly dysregulated by prostate cancer and could perfectly distinguish tumor-bearing mice. VOCs in human urine could not only classify any type of prostate cancer with moderate accuracy but could separate aggressive grades with higher sensitivity and specificity. Lastly, there was an overlap in VOC structure and functionality between the mouse and human urine analyses which shows the merit of utilizing murine models for identifying candidate VOC biomarkers for cancer. Canines can identify prostate cancer with high accuracy by smelling volatile organic compounds (VOCs) in urine. Previous studies have identified VOC biomarkers for prostate cancer utilizing solid phase microextraction (SPME) gas chromatography–mass spectrometry (GC-MS) but have not assessed the ability of VOCs to distinguish aggressive cancers. Additionally, previous investigations have utilized murine models to identify biomarkers but have not determined if the results are translatable to humans. To address these challenges, urine was collected from mice with prostate cancer and men undergoing prostate cancer biopsy and VOCs were analyzed by SPME GC-MS. Prior to analysis, SPME fibers/arrows were compared, and the fibers had enhanced sensitivity toward VOCs with a low molecular weight. The analysis of mouse urine demonstrated that VOCs could distinguish tumor-bearing mice with 100% accuracy. Linear discriminant analysis of six VOCs in human urine distinguished prostate cancer with sensitivity = 75% and specificity = 69%. Another panel of seven VOCs could classify aggressive cancer with sensitivity = 78% and specificity = 85%. These results show that VOCs have moderate accuracy in detecting prostate cancer and a superior ability to stratify aggressive tumors. Furthermore, the overlap in the structure of VOCs identified in humans and mice shows the merit of murine models for identifying biomarker candidates. [ABSTRACT FROM AUTHOR]

In this study, the influence of a new plant-based biostimulant (Bortan) on physiological and aromatic traits of rocket (Diplotaxis tenuifolia L. var. Pamela) was monitored by evaluating physico-chemical parameters (fresh and dry weight, leaf color and chlorophyll content) and biochemical traits (total phenolic compound (TP), total flavonoids (TF), ascorbic acid (AA) and antioxidant activity (AOX). Volatile profiles were also analyzed by headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry, allowing the detection of 32 volatiles belonging to 5 chemical classes. Compared to the control, Bortan application enhanced leaf pigment content, including chlorophyll a, b and carotenoids (+10%, +16% and +28%, respectively) and increased TP (+34%), TF (+26%), AA (+19%) amonts and AOX value (+16%). Principal component analysis revealed a significant discrimination between the two samples. Specifically, treated samples were mainly associated with "green-leaf" volatiles, namely hexanal and 2-hexenal, 3-hexenal and 1-penten-3-one, while control rocket was directly correlated with several alcohols and to all isothiocyanates, associated with the sulfur-like odor of rocket. These findings can add further support, both for farmers and the agro-food industry, in choosing PBs as a new and sustainable practice in complementing enhanced yields with premium-quality produce. To confirm these preliminary data, further experiments are needed by enlarging the sample size, testing different concentrations of Bortan and/or using other food crops. [ABSTRACT FROM AUTHOR]

Metal oxide (MOx) gas sensors have attracted considerable attention from both scientific and practical standpoints. Due to their promising characteristics for detecting toxic gases and volatile organic compounds (VOCs) compared with conventional techniques, these devices are expected to play a key role in home and public security, environmental monitoring, chemical quality control, and medicine in the near future. VOCs (e.g., acetone) are blood-borne and found in exhaled human breath as a result of certain diseases or metabolic disorders. Their measurement is considered a promising tool for noninvasive medical diagnosis, for example in diabetic patients. The conventional method for the detection of acetone vapors as a potential biomarker is based on spectrometry. However, the development of MOx-type sensors has made them increasingly attractive from a medical point of view. The objectives of this review are to assess the state of the art of the main MOx-type sensors in the detection of acetone vapors to propose future perspectives and directions that should be carried out to implement this type of sensor in the field of medicine. [ABSTRACT FROM AUTHOR]

Enhanced volatile organic compounds (VOCs) observations were made on ozone-exceeding days in June 2020 in Linyi, China. A total of 69 VOCs were collected (1 alkyne, 29 alkanes, 10 alkenes, 14 aromatic hydrocarbons, and 15 oxygenated volatile organic compounds (OVOCs)). The average concentration of total VOCs (TVOCs) was 36.0 ± 0.66 ppb, and the top three VOCs components were alkanes, OVOCs, and aromatic hydrocarbons, which accounted for 40.75%, 27.02%, and 11.30%, respectively. Based on the positive matrix factorization (PMF) model, the main sources of VOCs in Linyi City were divided into vehicle exhaust sources (39.11%), biomass combustion sources (21.82%), oil and gas volatilization sources (21.46%), and solvent use sources (17.61%). The ozone formation potential (OFP) contribution rate was dominated by alkenes, OVOCs, and aromatics, with contribution rates of 26.37%, 25.30%, and 23.65%, respectively. The top six VOCs that contributed the most to the OFP were formaldehyde, acetaldehyde, 1-butene, butadiene, trans-2-butene, and propylene. The empirical kinetic modelling approach (EKMA) curve indicated that the in situ ozone (O3) production was limited by VOCs, and reducing the concentration of O3 precursors in accordance with the VOCs/NOx concentration ratio of 1.15 can control O3 pollution more effectively. [ABSTRACT FROM AUTHOR]

BACKGROUND: Endoclita signifer is a polyphagous lepidopteran species of eucalyptus that selects its hosts in the third-instar larval period. To understand how it adapts to its host during development, we studied the olfactory responses of late-stage (fifth)-instar larvae to the dynamic chemical environment they encounter. RESULTS: Thirty-two volatiles from eucalyptus trunk and soil were identified, among which 14 showed electroantennal activity and five were identified as new. Further behavioral bioassay showed that both β-pinene and the imitation ratio of six key volatile in eucalyptus trunk were attractive to the fifth-instar larvae, but both eliminated and increased β-pinene in the mixture decreased the choice ratio and showed no attraction. Although E. signifer larvae shifted their attraction from o-cymene at the third-instar stage to β-pinene at the fifth-instar stage in a single volatile, the appropriate ratio of the main compounds in eucalyptus trunk volatile is the key to the behavior choice of fifth-instar larvae. CONCLUSION: The switch in olfactory attraction to different compounds between fifth- and third-instar larvae indicated an olfactory plasticity between third- and fifth-instar larvae. And the particular blend mediated the highly specialized communication interactions specificity between fifth-instar larvae and eucalyptus trunk volatile indicated the specialized host adaptation to fifth-instar larvae. This enhances understanding of how the primitive lepidopteran E. signifier, as a native pest, adapts to introduced eucalyptus. Moreover, this study provides knowledge for the screening and development of target volatiles for trapping and managing E. signifer larvae. [ABSTRACT FROM AUTHOR]

A wide range of volatile organic solvents, including aliphatic and aromatic hydrocarbons, alcohols, and ketones, are used in the production of paints, and they comprise more than 30% of the ingredients of paints. The present study was designed to evaluate the occupational exposure to 15 volatile organic compounds (VOCs, including benzene, toluene, ethylbenzene, xylene, styrene, n-hexane, n-heptane, n-nonane, trichloroethylene, tetrachloroethylene, n-butyl acetate, n-octane, n-decane, dichlorofluoromethane, and acetone) in Iranian paint production factories and subsequently, the associated health risks. The samples were collected from the respiratory zone of workers using the NIOSH 1501 method, and their qualitative and quantitative characterization was performed using gas chromatography-mass spectrometry and gas chromatography-flame ionization detector, respectively. The individual concentrations of VOCs ranged from 23.76 ± 0.57 µg m−3 (acetone) to 92489.91 ± 0.65 µg m−3 (m,p-xylene). The predominant compounds were m,p-xylene (up to 92489.91 ± 0.65 µg m−3), ethylbenzene (up to 91188.95 ± 0.34 µg m−3), and toluene (up to 46088.84 ± 0.14 µg m−3). The non-cancer risks of benzene, n-nonane, trichloroethylene, tetrachloroethylene, xylene, and ethylbenzene surpassed the reference value in most of the sectors. In addition, total lifetime risks of cancer were in the range of 1.8 × 10−5–3.85 × 10−3, suggesting that there was a risk of carcinogenesis in all studied sections, mainly due to ethylbenzene and benzene. Considering their high exposure concentrations and their associated non-carcinogenic and carcinogenic risks, biological monitoring of workers and the use of technical and modern engineering control measures are recommended. [ABSTRACT FROM AUTHOR]

Background: Volatile organic compound (VOC) profiles as biomarkers for hepatocellular carcinoma (HCC) are understudied. We aimed to identify VOCs from the exhaled breath for HCC diagnosis and compare the performance of VOCs to alpha-fetoprotein (AFP). The performance of VOCs for predicting treatment response and the association between VOCs level and survival of HCC patients were also determined. Methods: VOCs from 124 HCC patients and 219 controls were identified using the XGBoost algorithm. ROC analysis was used to determine VOCs performance in differentiating HCC patients from controls and in discriminating treatment responders from non-responders. The association between VOCs and the survival of HCC patients was analyzed using Cox proportional hazard analysis. Results: The combination of 9 VOCs yielded 70.0% sensitivity, 88.6% specificity, and 75.0% accuracy for HCC diagnosis. When differentiating early HCC from cirrhotic patients, acetone dimer had a significantly higher AUC than AFP, i.e., 0.775 vs. 0.714, respectively, p = 0.001. Acetone dimer classified HCC patients into treatment responders and non-responders, with 95.7% sensitivity, 73.3% specificity, and 86.8% accuracy. Isopropyl alcohol was independently associated with the survival of HCC patients, with an adjusted hazard ratio of 7.23 (95%CI: 1.36–38.54), p = 0.020. Conclusions: Analysis of VOCs is a feasible noninvasive test for diagnosing and monitoring HCC treatment response. [ABSTRACT FROM AUTHOR]

This study investigated the indoor environment quality (IEQ) of eight office buildings of interest due to: (a) their location at the region of Western Macedonia, Greece, which is an area characterized by aggravated air quality and is currently in a transition phase because of changes in the energy production strategy to reduce the use of lignite as an energy fuel; and (b) the survey's timing, characterized by new working conditions implemented during the COVID-19 pandemic period. In-site measurements were performed to identify the indoor air pollutants to which the occupants were exposed, while questionnaires were collected regarding the participants' perception of the working environment conditions, indoor air quality, and health symptoms. The statistical analysis results showed that the most-reported health symptoms were headache, dry eyes, and sneezing. The acceptance of new working conditions showed a significant correlation with their overall comfort and health perception. Occupants in offices with higher pollutant concentrations, such as NO2, benzene and toluene, were more likely to report health symptoms. The evaluation of the plausible health risks for the occupants of the buildings with carcinogenic and no-cancer models showed that health problems could exist despite low pollutant concentration levels. [ABSTRACT FROM AUTHOR]

Meat is a rich source of different volatile compounds. The final flavor of meat products depends on the raw material and processing parameters. Changes that occur in meat include pyrolysis of peptides and amino acids, degradation of sugar and ribonucleotides, Maillard's and Strecker's reactions, lipid oxidation, degradation of thiamine and fats, as well as microbial metabolism. A review of the volatile compounds' formation was carried out and divided into non-thermal and thermal processes. Modern and advanced solutions such as ultrasounds, pulsed electric field, cold plasma, ozone use, etc., were described. The article also concerns the important issue of determining Volatile Organic Compounds (VOCs) markers generated during heat treatment. [ABSTRACT FROM AUTHOR]

Background: Some VOCs are identified as endocrine-disrupting chemicals (EDCs), interfering with the effect of sex hormones. However, no studies focused on the common spectrum of environmental VOCs exposure affecting sex hormones in the average male population. Objectives: We aimed to explore the association between VOCs and sex hormones in American adult males using multiple statistical models. Methods: The generalized linear (GLM), eXtreme Gradient Boosting (XGBoost), weighted quantile sum (WQS), Bayesian kernel machine regression (BKMR) and stratified models were used to evaluate the associations between Specific Volatile Organic Compounds and sex hormones in American adult male from NHANES 2013-2016. Results: Pearson correlation model revealed the potential co-exposure pattern among VOCs. XGBoost algorithm models and the WQS model suggested the relative importance of VOCs. BKMR models reveal that co-exposure to the VOCs was associated with increased Testosterone (TT), Estradiol (E2), SHBG and decreased TT/E2. GLM models revealed specific VOC exposure as an independent risk factor causing male sex hormones disorders. Stratified analysis identified the high-risk group on the VOCs exposures. We found Blood 2,5-Dimethylfuran in VOCs was the most significant effect on sex hormones in male. Testosterone increased by 213.594 (ng/dL) (124.552, 302.636) and estradiol increased by 7.229 (pg/mL) for each additional unit of blood 2,5-Dimethylfuran (ng/mL). Conclusion: This study is an academic illustration of the association between VOCs exposure and sex hormones, suggesting that exposure to VOCs might be associated with sex hormone metabolic disorder in American adult males. [ABSTRACT FROM AUTHOR]

Based on one-year observation, the concentration, sources, and potential source areas of volatile organic compounds (VOCs) were comprehensively analyzed to investigate the pollution characteristics of ambient VOCs in Haikou, China. The results showed that the annual average concentration of total VOCs (TVOCs) was 11.4 ppbV, and the composition was dominated by alkanes (8.2 ppbV, 71.4%) and alkenes (1.3 ppbV, 20.5%). The diurnal variation in the concentration of dominant VOC species showed a distinct bimodal distribution with peaks in the morning and evening. The greatest contribution to ozone formation potential (OFP) was made by alkenes (51.6%), followed by alkanes (27.2%). The concentrations of VOCs and nitrogen dioxide (NO 2) in spring and summer were low, and it was difficult to generate high ozone (O 3) concentrations through photochemical reactions. The significant increase in O 3 concentrations in autumn and winter was mainly related to the transmission of pollutants from the northeast. Traffic sources (40.1%), industrial sources (19.4%), combustion sources (18.6%), solvent usage sources (15.5%) and plant sources (6.4%) were identified as major sources of VOCs through the positive matrix factorization (PMF) model. The southeastern coastal areas of China were identified as major potential source areas of VOCs through the potential source contribution function (PSCF) and concentration-weighted trajectory (CWT) models. Overall, the concentration of ambient VOCs in Haikou was strongly influenced by traffic sources and long-distance transport, and the control of VOCs emitted from vehicles should be strengthened to reduce the active species of ambient VOCs in Haikou, thereby reducing the generation of O 3. [Display omitted]. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are a crucial kind of pollutants in the environment due to their obvious features of severe toxicity, high volatility, and poor degradability. It is particularly urgent to control the emission of VOCs due to the persistent increase of concentration and the stringent regulations. In China, clear directions and requirements for reduction of VOCs have been given in the "national plan on environmental improvement for the 13th Five-Year Plan period". Therefore, the development of efficient technologies for removal and recovery of VOCs is of great significance. Recovery technologies are favored by researchers due to their advantages in both recycling VOCs and reducing carbon emissions. Among them, adsorption and membrane separation processes have been extensively studied due to their remarkable industrial prospects. This overview was to provide an up-to-date progress of adsorption and membrane separation for removal and recovery of VOCs. Firstly, adsorption and membrane separation were found to be the research hotspots through bibliometric analysis. Then, a comprehensive understanding of their mechanisms, factors, and current application statuses was discussed. Finally, the challenges and perspectives in this emerging field were briefly highlighted. [Display omitted]. [ABSTRACT FROM AUTHOR]

Economic development brings environmental challenges of which air pollution poses serious risks to humans and ecosystems. Air pollutants include volatile organic compounds (VOCs), inorganic air pollutants (IAPs) and particulate matter (PMs). Plant leaves may reduce such air pollution through adsorption and stomatal absorption. At the same time, air pollutants enter soil and root zones due to its content in rain and leaf fall. Microorganisms degrade and transform air pollutions. However, the efficiency of phytoremediation and bioremediation is slow and the use of plant-microbe interactions may therefore greatly enhance the efficiency of phytoremediation. The release of chemicals from plants leads to a mutual interaction with the microbiome that promotes the growth of the plant itself, thus enhancing degradation and detoxification of interleaf and inter-root air pollutants. Here we review the current research progress on combined plant-microbe action and discusses the interaction between plants and associated microorganisms while providing perspectives for future research in phytotechnologies. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Accumulating evidence have shown a significant correlation between urinary volatile organic compounds (VOCs) profile and the manifestation of several physiological and pathological states, including liver diseases. Previous studies have investigated the urinary metabolic signature as a non-invasive tool for the early discrimination between non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH), which nowadays represents one of the most important challenges in this context, feasible only by carrying out liver biopsy. Objectives: The aim of the study was to investigate the differences in the urinary VOCs profiles of non-alcoholic fatty liver disease (NAFLD) patients, diabetes mellitus (T2DM) subjects and NAFLD/T2DM patients. Methods: Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC-MS) was applied to profile the urinary VOCs. Urine samples were analysed both under acid and alkaline conditions, to obtain a range of urinary volatiles with different physicochemical properties. Results: Urinary VOCs profiles of 13 NAFLD patients, 13 T2DM subjects and 13 NAFLD/T2DM patients were investigated by multivariate and univariate data analysis techniques which allowed to identify 21 volatiles under alkaline conditions able to describe the NAFLD/T2DM group concerning the other two groups. Conclusion: Our results suggest that VOCs signatures can improve the knowledge of the pathological condition where NAFLD coexists with T2DM and discovering new features that are not simply the sum of the two diseases. These preliminary findings may be considered as hypothesis-generating, to be clearly confirmed by larger prospective investigations. [ABSTRACT FROM AUTHOR]

The petrochemical industry is regarded as the main source of anthropogenic VOCs emissions in China. As one of the main sources of unorganized emissions, circulating water is scarcely studied and reported. In this research, six circulating water systems (LC2X, HGLY, YJ, XJ, LC4X and LC5X) of a typical petrochemical enterprise were selected as targets to characterize VOCs emitted from such unorganized emissions. The results showed that there was a great difference in the VOCs disorganized emissions from the six circulating water systems, among which the main VOCs of HG2X, HGLY and YJ were oxygen-containing VOCs (OVOCs), accounting for about 48.0–81.2%. The main compounds of XJ, LC4X and LC5X were alkynes (89.1%), aromatic hydrocarbons (69.7%) and alkane (50.1%), respectively. TVOCs ranged from 276.0 to 23,009.6 µg·m−3. Based on POC test results, VOCs emissions of the circulating water system were 1237.5 tons, indicating further control was needed. As for their ambient impact, XJ had higher OFP contribution, and the OFP values of the six systems ranged from 823.3 to 145,739.0 µg·m−3, among which the major contributors were aromatic hydrocarbons (0.2–85.1%), OVOCs (0.1–77.2%) and alkynes (1.7–97.6%). In addition, aromatic hydrocarbons showed the largest contribution of the potential of SOA generation, which was more than 88.0%. As far as control was concerned, the replacement of an open cooling tower to closed cooling tower combined with regular POC detection will be an efficient way to control VOCs from such sources. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) and a polyaniline derivative (poly (2,5‐dimethyl aniline)) are evaluated for their sensitivity towards formaldehyde. Among the two polymer backbones evaluated, polyaniline seems more sensitive towards formaldehyde. Therefore, to further enhance sensitivity towards formaldehyde, polyaniline is doped with different weight percentages of indium oxide and further evaluated for its sensing capabilities such as sensitivity, selectivity, and stability. It is found that PANI with 1.25 wt% of In2O3 is most sensitive towards formaldehyde, while PANI with 5 wt% of In2O3 is most selective towards formaldehyde over benzene interferent. It is observed that sensitivity and selectivity trends for PANI doped with different wt% of In2O3 are reverse of each other. All sensing materials are found stable. [ABSTRACT FROM AUTHOR]

A growing population coupled with a higher demand for food is putting pressure on agriculture. The use of synthetic pesticides and chemical fertilizers allowed us to boost agricultural productions, but at a great environmental cost. Exploitation of beneficial microorganism (BM)-plant interactions has been proposed as an eco-friendly solution to improve plant resistance to stresses and to increase productivity sustainably. We provide an overview of scientific evidence that this positive interaction is often mediated also by the release of microbial Volatile Organic Compounds (mVOCs). A few mVOCs are reported to have a double, not mutually exclusive, positive effect on plants, as plant growth promoters, and/or inducers of resistance against biotic and abiotic stress factors. They may also alter plant VOCs indirectly improving plant performances. However, mechanisms and functions of mVOCs need deeper investigation. By understanding mVOC modes of action on plants, further tools for sustainably improving plant productivity in agro-ecosystems may become soon available. [ABSTRACT FROM AUTHOR]

To analyse the effects of initial water content (IWC) and temperature on the adsorption behaviour of VOCs on activated carbon (AC), the grand canonical Monte Carlo (GCMC) and molecular dynamics (MD) methods were used. Benzene and acetone are regarded as two representative components of VOCs, and their adsorption properties in AC models with four different IWC at 298.15 K were investigated. Their adsorption properties at four different temperatures (278.15, 288.15, 298.15, and 308.15 K) were also investigated. The simulated pressures were set in the range of 3 × 10−4 to 3 kPa (benzene) and 10 × 10−4 to 10 kPa (acetone). The results show that water molecules can impede the adsorption of benzene and acetone, decreasing the saturated adsorption capacity, the isosteric heat, and monomolecular interaction energy. However, the pre-loaded water molecules can enhance the electrostatic interaction at low pressure, which affects the isosteric heat and monomolecular interaction energy, but the pore volume is still the main influencing factor. Before reaching the saturated adsorption capacity, the higher the temperature, the lower the adsorption capacity, and the monomolecular interaction energy follows the same trend. The results provide mechanistic insights into how the IWC and temperature affect the adsorption properties of AC for VOCs. [ABSTRACT FROM AUTHOR]

Quorum sensing (QS) is often defined as a mechanism of microbial communication that can regulate microbial behaviors in accordance with population density. Much is known about QS mechanisms in bacteria, but fungal QS research is still in its infancy. In this study, the molecules constituting the volatolomes of the plant pathogenic fungi Fusarium culmorum and Cochliobolus sativus have been identified during culture conditions involving low and high spore concentrations, with the high concentration imitating overpopulation conditions (for QS stimulation). We determined that volatolomes emitted by these species in conditions of overpopulation have a negative impact on their mycelial growth, with some of the emitted molecules possibly acting as QSM. Candidate VOCs related to QS have then been identified by testing the effect of individual volatile organic compounds (VOCs) on mycelial growth of their emitting species. The antifungal effect observed for the volatolome of F. culmorum in the overpopulation condition could be attributed to ethyl acetate, 2-methylpropan-1-ol, 3-methylbutyl ethanoate, 3-methylbutan-1-ol, and pentan-1-ol, while it could be attributed to longifolene, 3-methylbutan-1-ol, 2-methylpropan-1-ol, and ethyl acetate for C. sativus in the overpopulation condition. This work could pave the way to a sustainable alternative to chemical fungicides. [ABSTRACT FROM AUTHOR]

Consumers of Australian cider are currently trending towards higher-quality cider products. As a result, boutique and craft cider breweries are expected to experience a period of growth over the next five years. Supporting this trend and subsequent growth is paramount to rebuilding the cider industry post-COVID-19. Many current practices and procedures, such as must clarification and biomass reduction in cider brewing, have been adapted from the beer and wine industry. While these practices are beneficial to the quality of cider and often promote the production of favourable volatile organic compounds (VOCs), the targeted enhancement of specific VOCs has not been achieved. This work investigates the specific enhancement of 2-phenylethanol (2-PE), which is known to improve the organoleptic properties of cider and provide potential health benefits through its antioxidant properties. The effect of three levels of biomass reduction (90%, 80%, and 0%) and five levels of L-phenylalanine (L-phe) saturation (0.5, 1.0, 1.5, 2.0, and 2.5 g L−1) for the enhanced production of 2-PE during cider fermentation were investigated. A high-performance liquid chromatography method was developed to accurately quantify the concentration of both 2-PE and L-phe, with a root-mean-square deviation (RSMD) of 0.41% and 1.60%, respectively. A significant increase in 2-PE production was achieved for all treatments, with 2-PE levels up to two orders of magnitude higher than respective controls. The highest 2-PE production was achieved by a moderate (80%) biomass reduction at a 2.5 g L−1 L-phe spike. Additionally, the VOC profile of several of the ciders was quantitively determined, and subsequent data underwent extensive chemometric analysis. Principle component analysis (PCA) showed that 2-PE and its derivatives (2-phenylethyl pivalate and phenylacetaldehyde) were correlated with the 80% biomass reduction treatment at the highest L-phe spike. Additionally, it was observed that several acids and alkanes were negatively correlated with the production of 2-PE and its derivatives. Additionally, hierarchical cluster analysis (HCA) showed clustering between the 80% and 90% biomass reduction treatments at several L-phe spike concentrations. However, the 0% biomass reduction treatments only showed similarity with other treatments with 0% biomass reduction. This work provides insight into the production of 2-PE during apple cider fermentation while building the foundation for more targeted biotechnological production of favourable compounds to improve cider quality. [ABSTRACT FROM AUTHOR]

Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The search for new sources of antimicrobial compounds has become an urgent need, due to the threat that the spread of bacterial resistance represents for global health and food safety. Brown macroalgae have been proposed as a great reservoir in the search for novel antimicrobial compounds. In this study, mid-polarity extracts were performed with a selection of 20 brown macroalgae species from northern Spain. The total polyphenol, carbohydrate and protein contents were quantified by spectrophotometry. The volatile organic compounds (VOCs) of whole macroalgae were also studied as a biomarker of their metabolic state in the representative species of the tested families by gas chromatography-mass spectrometry (GC-MS). The antimicrobial potential of the extracts was assessed by a disk diffusion assay against 20 target bacteria and further determinations of the minimum inhibitory (MIC) and minimum bactericidal concentrations (MBC) were performed by a microdilution assay for the active extracts. Ericaria selaginoides, Bifurcaria bifurcata and Dictyota dichotoma showed an antimicrobial effect against six Gram-positive strains: Bacillus cereus, Bacillus subtilis, Geobacillus stearothermophilus, Listeria monocytogenes, Staphylococcus aureus and Staphylococcus haemolyticus. The phenolic content was generally higher in the extracts that showed antimicrobial activity, followed by carbohydrates and low contents of proteins. The results obtained in this study reveal the potential of brown macroalgae as a promising alternative source of antimicrobial compounds as functional ingredients for the application in industrial fields. [ABSTRACT FROM AUTHOR]

Objectives Using a mobile laboratory equipped with Proton Transfer Reaction-Time of Flight/Mass Spectrometry (PTR-ToF-MS), we investigate the degree of air pollution level in the petrochemical industrial complex by investigating the distribution characteristics of air pollutants and tracking emission sources. Methods The research area within the petrochemical industrial complex was measured three times each at dawn, day, night, and the distribution of VOCs at each time was investigated and presented as a pollution map. In the emission source tracking, hot spot (high-concentration) wes found by mobile monitoring, and the emission source was closely tracked by stationary monitoring. Results and Discussion Acetaldehyde measured in the petrochemical industrial complex was confirmed to have the highest 3 to 5 degrees by direct olfactory method. In most instances the highest concentration was at dawn, potentially due to stagnant pollutants caused by temperature reversal. It was observed that the probability of finding an hot spot was higher during dawn and that it was significantly affected by the wind direction and speed at the time of measurement. When tracking the emission sources, appropriate areas of concern for contamination were selected on the basis of the stationary monitoring results, which were obtained from areas showing high concentrations after mobile monitoring. Conclusion As a result of the investigation of the distribution characteristics and emission sources of air pollutants in the petrochemical industrial complex, we found that acetaldehyde was the major pollutant and presented an efficient method to search for areas of concern for air pollution. Through these results, it is expected that emission sources can be managed more efficiently.

Abstract Background Plant growth-promoting rhizobacteria (PGPR) release volatile organic compounds (VOCs), which promote plant growth. Results A potential PGPR strain GX14001 was isolated from marine samples, and the VOCs produced by GX14001 significantly promoted tobacco (Nicotiana benthamiana) growth in a plate experiment. Based on 16S rRNA sequence alignment and physiological and biochemical characterization, GX14001 was identified as Microbacterium aurantiacum. Comparative transcriptome analysis was conducted between GX14001 VOCs-treated tobacco and the control; it was found that 1286 genes were upregulated and 1088 genes were downregulated. Gene ontology (GO) analysis showed that upregulated genes were involved in three biological processes: polysaccharide metabolic, polysaccharide catabolic and carbohydrate metabolic. The downregulated genes were involved in six biological processes, namely cell redox homeostasis, cellular homeostasis, carbohydrate metabolic process, homeostatic process, obsolete electron transport, and regulation of biological quality. Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis showed that 190 upregulated differentially expressed genes were mainly involved in plant hormone signal transduction, phenylpropyl biosynthesis, plant–pathogen interaction, and flavonoid biosynthesis. The 148 downregulated differentially expressed genes were mainly involved in plant hormone signal transduction and the metabolism of ascorbic, aldehyde, and pyruvate acids. Further analysis revealed that many genes were differentially expressed in the metabolic pathways of plant hormone signals, which were speculated to be the main reason why GX14001 VOCs promoted tobacco growth. To further study its regulatory mechanism, we found that GX14001 promoted plant growth through auxin, salicylic acid, and gibberellin in Arabidopsis mutant experiments. Conclusion The VOCs produced by Microbacterium aurantiacum GX14001 may promote the growth of tobacco through the auxin, salicylic acid and gibberellin pathways.

Volatile organic compounds (VOCs) are one of the main pollutants in industrial painting. Monitoring VOCs in painting workplaces is one of the keys to protect the health of operators, reduce environmental pollution, and ensure the safety production of painting industry. The effects of time, wind speed and space position on the concentration distribution of VOCs were studied by mathematical analysis. Results showed that the concentration of VOCs was positively proportional to the spraying time in the spraying process. The concentration of VOCs was significantly reduced by air circulation, and when the air circulation speed was 1.5 m/s, the VOCs concentration decreased by 80.7% compared to that under the windless environment. According to the distribution law of VOCs at different axial and radial distances of the nozzle, the measuring position of the PID gas sensor in the spraying workshop was determined. In the area where the axial distance was 1.6～2.0 m and the radial distance was 0.3～0.4 m, the concentration of VOCs reached a stable value under the windless environment. Therefore, installing the sensor in this area to avoid air circulation as far as possible could achieve better monitoring effect and avoid affecting the normal spraying operation.