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Volatile organic compound analysis

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https://www.readbyqxmd.com/read/29324768/identifying-human-diamine-sensors-for-death-related-putrescine-and-cadaverine-molecules
#1
Cristina Izquierdo, José C Gómez-Tamayo, Jean-Christophe Nebel, Leonardo Pardo, Angel Gonzalez
Pungent chemical compounds originating from decaying tissue are strong drivers of animal behavior. Two of the best-characterized death smell components are putrescine (PUT) and cadaverine (CAD), foul-smelling molecules produced by decarboxylation of amino acids during decomposition. These volatile polyamines act as 'necromones', triggering avoidance or attractive responses, which are fundamental for the survival of a wide range of species. The few studies that have attempted to identify the cognate receptors for these molecules have suggested the involvement of the seven-helix trace amine-associated receptors (TAARs), localized in the olfactory epithelium...
January 11, 2018: PLoS Computational Biology
https://www.readbyqxmd.com/read/29319815/chemical-analysis-and-simulated-pyrolysis-of-tobacco-heating-system-2-2-compared-to-conventional-cigarettes
#2
Xiangyu Li, Yanbo Luo, Xingyi Jiang, Hongfei Zhang, Fengpeng Zhu, Shaodong Hu, Hongwei Hou, Qingyuan Hu, Yongqiang Pang
Introduction: Tobacco Heating System 2.2 (THS 2.2, marketed as iQOS), is a heat-not-burn (HNB) tobacco product that has been successfully introduced to global markets. Despite its expanding market, few independent and systematic researches into THS 2.2 have been carried out to date. Methods: We tested a comprehensive list of total particulate matter (TPM), water, tar, nicotine, propylene glycol, glycerin, carbon monoxide, volatile organic compounds, aromatic amines, hydrogen cyanide, ammonia, N-nitrosamines, phenol, and polycyclic aromatic hydrocarbon under both ISO and HCI regimes...
January 8, 2018: Nicotine & Tobacco Research: Official Journal of the Society for Research on Nicotine and Tobacco
https://www.readbyqxmd.com/read/29297926/combining-color-chart-colorimetric-measurement-and-chemical-compounds-for-postharvest-quality-of-white-wine-grapes
#3
Marco Sollazzo, Simone Baccelloni, Claudio D'Onofrio, Andrea Bellincontro
BACKGROUND: This paper provides data for the potential use of a color chart to establish the best quality of white wine grape destined to postharvest processing. Grechetto, Vermentino and Muscat of Alexandria white wine varieties, were tested by sampling berries at different dates along quality attributes evolution. A color chart and reflectance spectrocolorimeter were used in combination with analyses of total carotenoids and chlorophylls in all three varieties and volatile organic compounds (VOCs) for Grechetto alone...
January 3, 2018: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/29297703/cancer-breath-testing-a-patent-review
#4
K M Mohibul Kabir, William A Donald
Human breath can contain thousands of volatile organic compounds (VOCs) and semi-volatile compounds that are related to metabolism and other biochemical processes. The presence of cancer cells can affect the identity and abundances of chemicals in breath when compared to those in healthy control subjects, which can be used to indicate the likelihood of a patient having cancer. Recently, the chemical analysis of exhaled breath from patients has been shown to be promising for diagnosing many different types of cancers, including lung, breast, colon, head and neck and prostate and pre-cancerous conditions (dysplasia)...
January 3, 2018: Expert Opinion on Therapeutic Patents
https://www.readbyqxmd.com/read/29295966/analysis-of-volatile-organic-compounds-in-the-breath-of-patients-with-stable-or-acute-exacerbation-of-chronic-obstructive-pulmonary-disease
#5
Alex Pizzini, Wojciech Filipiak, Johannes Wille, Clemens Ager, Helmut Wiesenhofer, Robert Kubinec, Jaroslav Blasko, Christoph Tschurtschenthaler, Christopher A Mayhew, Günter Weiss, Rosa Bellmann-Weiler
Chronic obstructive pulmonary disease (COPD) is a major cause of death worldwide. Acute exacerbations (AECOPD), caused by infectious and non-infectious agents, contribute to an increase in mortality. The diagnostic procedure of AECOPD is mainly based on clinical features. The aim of this pilot study was to identify whether volatile organic compounds (VOCs) in breath could be used to discriminate for acute exacerbated COPD. Three patient groups were included in this controlled study: AECOPD patients (n= 14, age mean ± SD: 71...
January 3, 2018: Journal of Breath Research
https://www.readbyqxmd.com/read/29294558/-rapid-determination-of-volatile-organic-compounds-in-workplace-air-by-protable-gas-chromatography-mass-spectrometer
#6
H B Zhu, C J Su, H F Tang, Z Ruan, D H Liu, H Wang, Y L Qian
Objective: To establish a method for rapid determination of 47 volatile organic compounds in the air of workplace using portable gas chromatography-mass spectrometer(GC-MS). Methods: The mixed standard gas with different concentration levels was made by using the static gas distribution method with the high purity nitrogen as dilution gas. The samples were injected into the GC-MS by a hand-held probe. Retention time and characteristic ion were used for qualitative analysis,and the internal standard method was usd for quantitation...
October 20, 2017: Chinese Journal of Industrial Hygiene and Occupational Diseases
https://www.readbyqxmd.com/read/29291449/health-risk-assessment-of-reclaimed-wastewater-a-case-study-of-a-conventional-water-reclamation-plant-in-nanjing-china
#7
Yongfeng Deng, Melvin Bonilla, Hongqiang Ren, Yan Zhang
Contaminated reclaimed wastewater has the potential to induce adverse effects on the health of wastewater workers and residents. However, few studies have focused on these health risks. In this study, we assessed the health risk of samples collected from different treatment processing units used in a typical water reclamation plant in Nanjing, China. Chemical analysis revealed that 40 semi-volatile organic compounds (SVOCs) and 6 N-nitrosamines (NAs) persisted after wastewater treatment. A health risk assessment revealed that the SVOCs in effluents pose negligible non-carcinogenic risk to wastewater workers and local residents as both the hazard quotient (HQ) and hazard index (HI) were all below 1...
December 29, 2017: Environment International
https://www.readbyqxmd.com/read/29291407/urine-volatile-organic-compounds-as-biomarkers-for-minimal-change-type-nephrotic-syndrome
#8
Desheng Liu, Nana Zhao, Mingao Wang, Xin Pi, Yue Feng, Yue Wang, Hongshuang Tong, Lin Zhu, Changsong Wang, Enyou Li
Urinary volatile organic compounds (VOCs) profiling has recently received considerable attention because it can be obtained noninvasively and conveniently while it can be successfully used in a variety of diseases and can provide unique biomarkers. The aim of current study was to investigate potential biomarkers between minimal change type nephrotic syndrome (MCNS) and normal. Urinary samples were collected from 38 minimal change type nephrotic syndrome patients and 15 healthy controls. Solid phase microextraction (SPME) and chromatography- mass spectrometry (GC-MS) were used to analysis the urinary metabolites...
December 29, 2017: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/29280625/water-resistant-polymeric-acid-membrane-catalyst-for-acetone-detection-in-the-exhaled-breath-of-diabetics
#9
Adam D Worrall, Zexin Qian, Jonathan Bernstein, Anastasios P Angelopoulos
Endogenous volatile organic compounds (VOC's) such as acetone in exhaled human breath are associated with metabolic conditions in the bloodstream. Development of compact, rapid detectors of exhaled breath chemical compo-sition in clinical settings is challenging due to the small sample size that can be collected during a single exhalation as well as spectroscopic interference by the abundance of water. In this paper, we show that the activity of a catalytic polymer membrane (Nafion® 117) toward the heterogeneous condensation reaction of immobilized resorcinol reagent with gas-phase acetone can be preserved even at 100% ambient relative humidity through the incorporation of organic acids such as vanillic or tiglic...
December 27, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/29280145/comparative-analysis-of-volatile-compound-profiles-of-propolis-from-different-provenances
#10
Lina G Mohtar, Sergio A Rodríguez, Mónica A Nazareno
BACKGROUND: Propolis is a complex mixture that honey bees produce from the exudates of various plants and presents many medicinal properties. Its chemical compositions varies according to the phytogeography characteristics of each region, among others. The aim of this study was to identify and characterize the volatile organic compounds (VOCs) present in Venezuelan propolis and compare with reference samples such as Brazilian and Argentinian ones. RESULTS: A total of 90 VOCs were identified in a series of propolis samples using both Solid-Phase Microextraction (SPME) and Dynamic Headspace (DHS), both coupled to C-EI-MS...
December 27, 2017: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/29279954/a-breath-of-information-the-volatilome
#11
M Mansurova, Birgitta E Ebert, Lars M Blank, Alfredo J Ibáñez
Volatile organic compounds (VOCs) are small molecular mass substances, which exhibit low boiling points and high-vapour pressures. They are ubiquitous in nature and produced by almost any organism of all kingdoms of life. VOCs are involved in many inter- and intraspecies interactions ranging from antimicrobial or fungal effects to plant growth promotion and human taste perception of fermentation products. VOC profiles further reflect the metabolic or phenotypic state of the living organism that produces them...
December 26, 2017: Current Genetics
https://www.readbyqxmd.com/read/29277946/discrimination-of-constructed-air-samples-using-multivariate-analysis-of-full-scan-membrane-introduction-mass-spectrometry-mims-data
#12
L C Richards, N G Davey, T M Fyles, C G Gill, E T Krogh
RATIONALE: Volatile and semi-volatile organic compounds (S/VOCs) are important atmospheric pollutants affecting both human and environmental health. They are directly measured as an unresolved mixture using membrane introduction mass spectrometry (MIMS). We apply chemometric techniques to discriminate, classify, and apportion air samples from a variety of sources. METHODS: Full scan mass spectra of lab constructed air samples were obtained using a polydimethylsiloxane membrane interface and an electron ionization ion trap mass spectrometer...
December 26, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/29277437/indoor-air-quality-iaq-evaluation-of-a-novel-tobacco-vapor-ntv-product
#13
Hirokazu Ichitsubo, Misato Kotaki
The impact of using a Novel Tobacco Vapor (NTV) product on indoor air quality (IAQ) was simulated using an environmentally-controlled chamber. Three environmental simulations were examined; two non-smoking areas (conference room and dining room) and one ventilated smoking area (smoking lounge). IAQ was evaluated by (i) measuring constituents in the mainstream NTV product emissions, (ii) and by determining classical environmental tobacco smoke (ETS) and representative air quality markers. Analysis of the mainstream emissions revealed that vapor from the NTV product is chemically simpler than cigarette smoke...
December 22, 2017: Regulatory Toxicology and Pharmacology: RTP
https://www.readbyqxmd.com/read/29274971/sensory-and-chemical-properties-of-gouda-cheese
#14
Y Jo, D M Benoist, A Ameerally, M A Drake
Gouda cheese is a washed-curd cheese that is traditionally produced from bovine milk and brined before ripening for 1 to 20 mo. In response to domestic and international demand, US production of Gouda cheese has more than doubled in recent years. An understanding of the chemical and sensory properties of Gouda cheese can help manufacturers create desirable products. The objective of this study was to determine the chemical and sensory properties of Gouda cheeses. Commercial Gouda cheeses (n = 36; 3 mo to 5 yr; domestic and international) were obtained in duplicate lots...
December 20, 2017: Journal of Dairy Science
https://www.readbyqxmd.com/read/29258171/synthesis-of-tio%C3%A2-with-hierarchical-porosity-for-the-photooxidation-of-propene
#15
Javier Fernández-Catalá, Laura Cano-Casanova, María Ángeles Lillo-Ródenas, Ángel Berenguer-Murcia, Diego Cazorla-Amorós
The elimination of volatile organic compounds (VOCs) at low concentration is a subject of great interest because these compounds are very harmful for the environment and human health. In this work, we have developed a synthesis methodology of TiO₂ that allows obtaining meso-macroporous materials with hierarchical porosity and with high thermal stability for their application as photocatalysts in the removal of VOCs, specifically propene. The materials synthesized in this work were characterized by Scanning electron microscope (SEM), Transmission electron microscopy (TEM), powder X-ray diffraction (XRD), Thermogravimetric Analysis (TG), and nitrogen adsorption...
December 16, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29238032/influence-of-fruit-ripening-on-color-organic-acid-contents-capsaicinoids-aroma-compounds-and-antioxidant-capacity-of-shimatogarashi-capsicum-frutescens
#16
Manikharda Manikharda, Makoto Takahashi, Mika Arakaki, Kaoru Yonamine, Fumio Hashimoto, Kensaku Takara, Koji Wada
Shimatogarashi (Capsicum frutescens) is a typical chili pepper domesticated in southern Japan. Important traits of Shimatogarashi peppers, such as color; proportion of organic acids, capsaicinoids, and aromatic compounds; and antioxidant activity in three stages of maturity (green (immature), orange (turning), and red (mature) stages) were characterized. The results indicated that the concentration of organic acids, including ascorbic, citric, and malic acid, increased during ripening. In addition, the amount of capsaicinoids, which are responsible for the pungent taste of chili peppers, increased as the fruit matured to the orange and red stages...
December 14, 2017: Journal of Oleo Science
https://www.readbyqxmd.com/read/29231889/exploring-the-caste-specific-multi-layer-defense-mechanism-of-formosan-subterranean-termites-coptotermes-formosanus-shiraki
#17
Abid Hussain, Ming-Yi Tian, Shuo-Yang Wen
The survival and foraging of Coptotermesformosanus Shiraki in a microbe-rich environment reflect the adaptation of an extraordinary, sophisticated defense mechanism by the nest-mates. We aimed to explore the host pathogen interaction by studying caste-specific volatile chemistry and genes encoding the antioxidant defense of winged imagoes, nymphs, soldiers and workers of Formosan subterranean termites. Qualitative analyses of C.formosanus Shiraki performed by HS-SPME/GC-MS showed considerable variations in the chemical composition of volatile organic compounds (VOCs) and their proportions among all the castes...
December 12, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/29231842/smell-of-cells-volatile-profiling-of-stem-and-non-stem-cell-proliferation
#18
Ann-Christin Bischoff, Peter Oertel, Pritam Sukul, Christian Rimmbach, Robert David, Jochen Schubert, Wolfram Miekisch
Bacterial and cell cultures are known to emit a large number of volatile organic compounds (VOCs). Conventional biochemical methods are often destructive, time-consuming and ex-pensive. In contrast, VOC analysis of headspace over cultures, may offer a non-destructive alternative to monitor cell proliferation and metabolism. VOC profiles from cultures of murine pluripotent stem cells and fibroblasts were assessed every 24 hours for 3 days. Pure cell media were measured as parallel controls. VOC analysis was highly standardized with respect to time of measurement and phases of cell growth...
December 12, 2017: Journal of Breath Research
https://www.readbyqxmd.com/read/29227091/a-vuv-excited-and-ch2cl2-h2o-amplified-ionization-coupled-mass-spectrometry-for-oxygenated-organics-analysis
#19
Bo Yang, Haixu Zhang, Jinian Shu, Pengkun Ma, Peng Zhang, Jingyun Huang, Zhen Li, Ce Xu
The mass spectrometry analysis of oxygenated volatile organic compounds (OVOCs) remains challenging due to their limited ionization efficiencies. In this study, we surprisingly found that, under VUV excitation, a gaseous mixture of CH2Cl2/H2O/analyte (OVOCs) in N2 buffer generated large amounts of H3O+ and protonated analyte even when the photon energy was lower than the ionization energy of the neutral species involved. In contrast to those obtained with VUV photoionization alone, the signal intensities of oxygenated organics can be amplified by more than three orders of magnitude...
December 11, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/29219314/isoprene-derived-organosulfates-vibrational-mode-analysis-by-raman-spectroscopy-acidity-dependent-spectral-modes-and-observation-in-individual-atmospheric-particles
#20
Amy Lynne Bondy, Rebecca Lynn Craig, Zhenfa Zhang, Avram Gold, Jason Douglas Surratt, Andrew P Ault
Isoprene, the most abundant biogenic volatile organic compound (BVOC) in the atmosphere, and its low-volatility oxidation products lead to secondary organic aerosol (SOA) formation. Isoprene-derived organosulfates formed from reactions of isoprene oxidation products with sulfate in the particle phase are a significant component of SOA and can hydrolyze forming polyols. Despite characterization by mass spectrometry, their basic structural and spectroscopic properties remain poorly understood. Herein, Raman microspectroscopy and density functional theory (DFT) calculations (CAM-B3LYP level of theory) were combined to analyze vibrational modes of key organosulfates, 3-methyltetrol sulfate esters and 2-methylglyceric acid sulfate esters (both racemic mixtures of two isomers), and hydrolysis products, 2-methyltetrols and 2-methylglyceric acid...
December 8, 2017: Journal of Physical Chemistry. A
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