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Volatile organic compound analysis

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https://www.readbyqxmd.com/read/27917180/role-of-the-gacs-sensor-kinase-in-the-regulation-of-volatile-production-by-plant-growth-promoting-pseudomonas-fluorescens-sbw25
#1
Xu Cheng, Viviane Cordovez, Desalegn W Etalo, Menno van der Voort, Jos M Raaijmakers
In plant-associated Pseudomonas species, the production of several secondary metabolites and exoenzymes is regulated by the GacS/GacA two-component regulatory system (the Gac-system). Here, we investigated if a mutation in the GacS sensor kinase affects the production of volatile organic compounds (VOCs) in P. fluorescens SBW25 (Pf.SBW25) and how this impacts on VOCs-mediated growth promotion and induced systemic resistance of Arabidopsis and tobacco. A total of 205 VOCs were detected by Gas Chromatography Mass Spectrometry for Pf...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/27905399/cellular-reactions-to-long-term-volatile-organic-compound-voc-exposures
#2
Johanna M Gostner, Johannes Zeisler, Mohammad Tauqeer Alam, Peter Gruber, Dietmar Fuchs, Kathrin Becker, Kerstin Neubert, Markus Kleinhappl, Stefan Martini, Florian Überall
Investigations of cellular processes initiated by volatile organic compounds (VOCs) are limited when modelling realistic long-term exposure scenarios at low concentrations. Exposure to indoor VOCs is associated with a range of adverse effects, but data on molecular changes at regulatory threshold limits are lacking. Activity analysis of VOC in vitro can be a valuable complement to inhalation toxicological evaluations. We developed an exposure platform that generates a stable VOC atmosphere and allows the exposure of cells for longer periods...
December 1, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27902490/detection-of-staphylococcus-aureus-in-cystic-fibrosis-patients-using-breath-voc-profiles
#3
A H Neerincx, B P Geurts, J van Loon, V Tiemes, J J Jansen, F J M Harren, L A J Kluijtmans, P J F M Merkus, S M Cristescu, L M C Buydens, R A Wevers
Staphylococcus aureus (S. aureus) is a common bacterium infecting children with cystic fibrosis (CF). Since current detection methods are difficult to perform in children, there is need for an alternative. This proof of concept study investigates whether breath profiles can discriminate between S. aureus infected and non-infected CF patients based on volatile organic compounds (VOCs). We collected exhaled breath of CF patients with and without S. aureus airways infections in which VOCs were identified using gas chromatography-mass spectrometry...
November 30, 2016: Journal of Breath Research
https://www.readbyqxmd.com/read/27900861/thermal-desorption-combined-with-atmospheric-pressure-photo-ionization-for-the-analysis-of-volatile-compounds-and-its-possible-applications
#4
Yury Kostyukevich, Ludmila Borisova, Alexey Kononikhin, Igor Popov, Eugene Kukaev, Eugene Nikolaev
We report an approach to study volatile organic compounds based on thermal desorption combined with atmospheric pressure photo ionization. The approach allows the sequential evaporation of different fractions of the sample, which simplifies the mass spectrum. We have applied the developed method for the detection of petroleum in vegetable oil. We have shown that in the negative mode, ions of fatty acids corresponding to vegetable oil dominates, while in the positive mode under relatively low temperature the light fraction of petroleum rapidly evaporates making it easy detectable...
2016: European Journal of Mass Spectrometry
https://www.readbyqxmd.com/read/27886068/effects-of-sampling-conditions-and-environmental-factors-on-fecal-volatile-organic-compound-analysis-by-an-electronic-nose-device
#5
Daniel J C Berkhout, Marc A Benninga, Ruby M van Stein, Paul Brinkman, Hendrik J Niemarkt, Nanne K H de Boer, Tim G J de Meij
Prior to implementation of volatile organic compound (VOC) analysis in clinical practice, substantial challenges, including methodological, biological and analytical difficulties are faced. The aim of this study was to evaluate the influence of several sampling conditions and environmental factors on fecal VOC profiles, analyzed by an electronic nose (eNose). Effects of fecal sample mass, water content, duration of storage at room temperature, fecal sample temperature, number of freeze-thaw cycles and effect of sampling method (rectal swabs vs...
November 23, 2016: Sensors
https://www.readbyqxmd.com/read/27881988/identification-of-a-solanum-pennellii-chromosome-4-fruit-flavor-and-nutritional-quality-associated-metabolite-qtl
#6
Zhongyuan Liu, Saleh Alseekh, Yariv Brotman, Yi Zheng, Zhangjun Fei, Denise M Tieman, James J Giovannoni, Alisdair R Fernie, Harry J Klee
A major resource for tomato quality improvement and gene discovery is the collection of introgression lines (ILs) of cultivated Solanum lycopersicum that contain different, defined chromosomal segments derived from the wild tomato relative, S. pennellii. Among these lines, IL4-4, in which the bottom of S. lycopersicum (cv. M82) chromosome 4 is replaced by the corresponding S. pennellii segment, is altered in many primary and secondary metabolites, including many related to fruit flavor and nutritional quality...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/27880857/conformational-flexibility-of-limonene-oxide-studied-by-microwave-spectroscopy
#7
Juan Jesus Lopez Gonzalez, María Mar Quesada-Moreno, Juan Ramón Avilés-Moreno, Thérèse R Huet, M Eugenia Sanz, Donatella Loru, Natasha Jarman
Monoterpenoids are biogenic volatile organic compounds (BVOCs) that play a major role in atmospheric chemistry, participating in the formation of aerosols. In this work, the monoterpenoid R-(+)-limonene oxide (C₁₀H₁₆O) has been characterized in the gas phase by Fourier transform microwave spectroscopy in a supersonic jet. Five conformers of limonene oxide, four equatorial and one axial considering the configuration of the isopropenyl group, have been unambiguously identified from the analysis of the rotational spectrum...
November 23, 2016: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/27875502/sniffing-out-paediatric-gastrointestinal-diseases-the-potential-of-volatile-organic-compounds-as-biomarkers-for-disease
#8
Martin Buijck, Daniel J C Berkhout, Evelien F J de Groot, Marc A Benninga, Marc P C van der Schee, Corneille Marie Frank Kneepkens, Nanne K H de Boer, Tim G J de Meij
The diagnostic work-up and follow-up of paediatric functional gastrointestinal disorders and organic conditions usually includes invasive tests, carrying a high burden on patients. There is a place, therefore, for novel, noninvasive disease-specific biomarkers. Volatile organic compounds (VOCs), originating from (patho)physiological metabolic processes in the human body, are excreted as waste products through all conceivable bodily excrements. The spectrum of VOCs harbours a magnificent source of information, with the potential to serve as noninvasive diagnostic biomarkers and to monitor disease activity...
December 2016: Journal of Pediatric Gastroenterology and Nutrition
https://www.readbyqxmd.com/read/27874211/characteristics-of-volatile-organic-compounds-produced-from-five-pathogenic-bacteria-by-headspace-solid-phase-micro-extraction-gas-chromatography-mass-spectrometry
#9
Juan Chen, Junni Tang, Hui Shi, Cheng Tang, Rong Zhang
The characteristics of volatile compounds from five different bacterial species, Escherichia coli O157:H7, Salmonella Enteritidis, Shigella flexneri, Staphylococcus aureus, and Listeria monocytogenes, growing, respectively, in trypticase soy broth were monitored by headspace solid-phase micro-extraction/gas chromatography-mass spectrometry. The results showed that most volatile organic compounds (VOCs) of five pathogens started to increase after the sixth to tenth hour. Methyl ketones and long chain alcohols were representative volatiles for three Gram-negative bacteria...
November 22, 2016: Journal of Basic Microbiology
https://www.readbyqxmd.com/read/27869110/volatile-organic-compound-markers-of-psychological-stress-in-skin-a-pilot-study
#10
H J Martin, M A Turner, S Bandelow, L Edwards, Svetlana Riazanskaia, C L P Thomas
The forehead was studied as a possible sampling site for capturing changes in volatile organic compound (VOC) profiles associated with psychological-stress. Skin-VOCs were sampled with a polydimethylsilicone (PDMS)-coupon and the resulting VOCs were recovered and analysed with two-stage thermal desorption gas chromatography-mass spectrometry. Fifteen young adult volunteers (19 years-26 years) participated in two interventions run in a randomised crossover design. One intervention, termed 'Neutral', required the participants to listen to peaceful music, the other, termed a 'paced audio serial addition task', required the participants to undertake a series of rapid mental arithmetic calculations in a challenging environment that induced a stress response...
November 21, 2016: Journal of Breath Research
https://www.readbyqxmd.com/read/27869104/comparative-analysis-of-the-volatile-metabolomes-of-pseudomonas-aeruginosa-clinical-isolates
#11
Heather D Bean, Christiaan A Rees, Jane E Hill
Pseudomonas aeruginosa is a nearly ubiquitous Gram-negative organism, well known to occupy a multitude of environmental niches and cause human infections at a variety of bodily sites, due to its metabolic flexibility, secondary to extensive genetic heterogeneity at the species level. Because of its dynamic metabolism and clinical importance, we sought to perform a comparative analysis on the volatile metabolome (the 'volatilome') produced by P. aeruginosa clinical isolates. In this study, we analyzed the headspace volatile molecules of 24 P...
November 21, 2016: Journal of Breath Research
https://www.readbyqxmd.com/read/27865659/using-long-term-air-monitoring-of-semi-volatile-organic-compounds-to-evaluate-the-uncertainty-in-polyurethane-disk-passive-sampler-derived-air-concentrations
#12
Eva Holt, Pernilla Bohlin-Nizzetto, Jana Borůvková, Tom Harner, Jiří Kalina, Lisa Melymuk, Jana Klánová
Much effort has been made to standardise sampling procedures, laboratory analysis, data analysis, etc. for semi volatile organic contaminants (SVOCs). Yet there are some unresolved issues in regards to comparing measurements from one of the most commonly used passive samplers (PAS), the polyurethane foam (PUF) disk PAS (PUF-PAS), between monitoring networks or different studies. One such issue is that there is no universal means to derive a sampling rate (Rs) or to calculate air concentrations (Cair) from PUF-PAS measurements for SVOCs...
January 2017: Environmental Pollution
https://www.readbyqxmd.com/read/27863835/metabolites-profiling-reveals-for-antimicrobial-compositional-differences-and-action-mechanism-in-the-toothbrushing-stick-miswak-salvadora-persica
#13
Mohamed A Farag, Sherifa Fahmy, Mouchira A Choucry, Mariam O Wahdan, Mahmoud Fahmi Elsebai
Among many plant species suitable for preparing toothbrushing sticks, miswak (Salvadora persica, family Salvadoraceae) is found the most effective tool for oral hygiene. S. persica possesses antibacterial, antiviral and antifungal effects against oral microbes, mostly due to its benzyl isothiocyanate content. To provide insight into S. persica chemical composition, volatile constituents from roots and stems of S. persica grown in Egypt and Saudi Arabia were profiled using solid-phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS)...
January 30, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/27862955/in-tube-extraction-for-the-determination-of-the-main-volatile-compounds-in-physalis-peruviana-l
#14
Magdalena Kupska, Henryk H Jeleń
An analytical procedure based on in-tube extraction followed by gas chromatography with mass spectrometry has been developed for the analysis of 24 main volatile components in cape gooseberry (Physalis peruviana L.) samples. According to their chemical structure, the compounds were organized into different groups: 1 hydrocarbon, 1 aldehyde, 4 alcohols, 4 esters and 14 monoterpenes. By single-factor experiments, incubation temperature, incubation time, extraction volume, extraction strokes, extraction speed, desorption temperature and desorption speed were determined as 60°C, 20 min, 1000 μL, 20, 50:50 μL/s, 280°C, 100 μL/s, respectively...
November 15, 2016: Journal of Separation Science
https://www.readbyqxmd.com/read/27862864/biological-relevance-of-volatile-organic-compounds-emitted-during-the-pathogenic-interactions-between-apple-plants-and-erwinia-amylovora
#15
Antonio Cellini, Giampaolo Buriani, Lorenzo Rocchi, Elena Rondelli, Stefano Savioli, Maria T Rodriguez Estrada, Simona M Cristescu, Guglielmo Costa, Francesco Spinelli
Volatile organic compounds emitted during the infection of apple (Malus pumila var. domestica) plants by Erwinia amylovora or Pseudomonas syringae pv. syringae were studied by gas chromatography-mass spectrometry and proton transfer reaction-mass spectrometry, and used to treat uninfected plants. Infected plants showed a disease specific emission of volatile organic compounds, including several bio-active compounds, such as hexenal isomers and 2,3-butanediol. Leaf growth promotion and a higher resistance to the pathogen, expressed as a lower bacterial growth and migration in plant tissues, were detected in plants exposed to volatile compounds from E...
November 15, 2016: Molecular Plant Pathology
https://www.readbyqxmd.com/read/27853412/significance-of-exhaled-breath-test-in-clinical-diagnosis-a-special-focus-on-the-detection-of-diabetes-mellitus
#16
REVIEW
Souvik Das, Saurabh Pal, Madhuchhanda Mitra
Analysis of volatile organic compounds (VOCs) emanating from human exhaled breath can provide deep insight into the status of various biochemical processes in the human body. VOCs can serve as potential biomarkers of physiological and pathophysiological conditions related to several diseases. Breath VOC analysis, a noninvasive and quick biomonitoring approach, also has potential for the early detection and progress monitoring of several diseases. This paper gives an overview of the major VOCs present in human exhaled breath, possible biochemical pathways of breath VOC generation, diagnostic importance of their analysis, and analytical techniques used in the breath test...
2016: Journal of Medical and Biological Engineering
https://www.readbyqxmd.com/read/27852216/from-cow-to-cheese-genetic-parameters-of-the-flavour-fingerprint-of-cheese-investigated-by-direct-injection-mass-spectrometry-ptr-tof-ms
#17
Matteo Bergamaschi, Alessio Cecchinato, Franco Biasioli, Flavia Gasperi, Bruno Martin, Giovanni Bittante
BACKGROUND: Volatile organic compounds determine important quality traits in cheese. The aim of this work was to infer genetic parameters of the profile of volatile compounds in cheese as revealed by direct-injection mass spectrometry of the headspace gas from model cheeses that were produced from milk samples from individual cows. METHODS: A total of 1075 model cheeses were produced using raw whole-milk samples that were collected from individual Brown Swiss cows...
November 16, 2016: Genetics, Selection, Evolution: GSE
https://www.readbyqxmd.com/read/27846067/detection-of-sepsis-in-preterm-infants-by-fecal-volatile-organic-compounds-analysis-a-proof-of-principle-study
#18
Daniel J C Berkhout, Hendrik J Niemarkt, Martin Buijck, Mirjam M van Weissenbruch, Paul Brinkman, Marc A Benninga, Anton H van Kaam, Boris W Kramer, Peter Andriessen, Nanne K H de Boer, Tim G J de Meij
OBJECTIVES: Several studies associated altered gut microbiota composition in preterm infants with late-onset sepsis (LOS), up to days prior to clinical onset of sepsis. However, microbiota analysis as early diagnostic biomarker is in clinical practice currently not feasible because of logistic aspects and high costs. Therefore, we hypothesized that analysis of fecal volatile organic compounds (VOC) may serve as non-invasive biomarker to predict LOS at a preclinical stage, since VOC reflect the composition and activity of intestinal microbial communities...
November 14, 2016: Journal of Pediatric Gastroenterology and Nutrition
https://www.readbyqxmd.com/read/27834896/development-of-an-exhaled-breath-monitoring-system-with-semiconductive-gas-sensors-a-gas-condenser-unit-and-gas-chromatograph-columns
#19
Toshio Itoh, Toshio Miwa, Akihiro Tsuruta, Takafumi Akamatsu, Noriya Izu, Woosuck Shin, Jangchul Park, Toyoaki Hida, Takeshi Eda, Yasuhiro Setoguchi
Various volatile organic compounds (VOCs) in breath exhaled by patients with lung cancer, healthy controls, and patients with lung cancer who underwent surgery for resection of cancer were analyzed by gas condenser-equipped gas chromatography-mass spectrometry (GC/MS) for development of an exhaled breath monitoring prototype system involving metal oxide gas sensors, a gas condenser, and gas chromatography columns. The gas condenser-GC/MS analysis identified concentrations of 56 VOCs in the breath exhaled by the test population of 136 volunteers (107 patients with lung cancer and 29 controls), and selected four target VOCs, nonanal, acetoin, acetic acid, and propanoic acid, for use with the condenser, GC, and sensor-type prototype system...
November 10, 2016: Sensors
https://www.readbyqxmd.com/read/27831543/a-distinct-colon-derived-breath-metabolome-is-associated-with-inflammatory-bowel-disease-but-not-its-complications
#20
Florian Rieder, Satya Kurada, David Grove, Frank Cikach, Rocio Lopez, Nishaben Patel, Amandeep Singh, Naim Alkhouri, Bo Shen, Aaron Brzezinski, Mark Baker, Claudio Fiocchi, Raed A Dweik
OBJECTIVES: The accuracy of available noninvasive biomarkers for diagnosis, stratification, and prediction of inflammatory bowel disease (IBD) courses is limited. We analyzed volatile organic compounds (VOCs) in the breath of IBD patients and controls for diagnosis and differentiation of IBD as well as their link with disease location, activity, and phenotype. METHODS: A prospective study of diagnostic testing was conducted, recruiting Crohn's disease (CD), ulcerative colitis (UC), other inflammatory gastrointestinal diseases (OGDs), and healthy controls (HCs), as well as subjects with ileal pouch anal anastomosis (IPAA)...
November 10, 2016: Clinical and Translational Gastroenterology
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