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volatile compound

Kyle D Custard, Kerri A Pratt, Siyuan Wang, Paul B Shepson
During springtime, unique halogen chemistry involving chlorine and bromine atoms controls the prevalence of volatile organic compounds, ozone, and mercury in the Arctic lower troposphere. In situ measurements of the chlorine monoxide radical (ClO) and its precursor Cl2, along with BrO and Br2, were conducted using chemical ionization mass spectrometry (CIMS) during the BRomine, Ozone, and Mercury EXperiment (BROMEX) near Barrow, Alaska in March 2012. To our knowledge, these data represent the first ClO measurements made using CIMS...
October 21, 2016: Environmental Science & Technology
Katayoun Mahdavi Ara, Farhad Raofie
Essential oils and volatile components of pomegranate (Punica granatum L.) peel of the Malas variety from Meybod, Iran, were extracted using supercritical fluid extraction (SFE) and hydro-distillation methods. The experimental parameters of SFE that is pressure, temperature, extraction time, and modifier (methanol) volume were optimized using a central composite design after a (2(4-1)) fractional factorial design. Detailed chemical composition of the essential oils and volatile components obtained by hydro-distillation and optimum condition of the supercritical CO2 extraction were analyzed by GC-MS, and seventy-three and forty-six compounds were identified according to their retention indices and mass spectra, respectively...
July 2016: Journal of Food Science and Technology
Ivana Generalić Mekinić, Ivica Blažević, Ivana Mudnić, Franko Burčul, Mia Grga, Danijela Skroza, Iva Jerčić, Ivica Ljubenkov, Mladen Boban, Mladen Miloš, Višnja Katalinić
Sea fennel, a rediscovered star of the coastal cuisine, has been investigated for its phytochemical profile and biological potential. Sea fennel flowers, stems and leaves were analyzed for essential oils (EOs) isolated by hydrodistillation, as well as non-volatiles obtained by ethanolic extraction. Limonene were found to be a dominant compound in EOs and ethanolic extracts; ranging from 57.5-74.2 % and 0.7-8.1 mg/g dry plant material, respectively. In addition total phenolic content was determined for ethanolic extracts...
July 2016: Journal of Food Science and Technology
Dong Bok Jeon, Young Shin Hong, Ga Hyun Lee, Yu Min Park, Cheong Mi Lee, Eun Yeong Nho, Ji Yeon Choi, Nargis Jamila, Naeem Khan, Kyong Su Kim
Tea contains characteristic volatile organic compounds, polyphenols, caffeine and catechins, and is therefore among the most widely consumed beverages all over the world. In this study, fresh Jukro tea leaves collected from Damyang-gun (Jeollanam-do) at 40, 60 and 90day growth stages, were semi-fermented. The volatile organic compounds (VOCs) were extracted by simultaneous distillation-solvent extraction (SDE) and analyzed by gas chromatography/mass spectrometry (GC/MS). Catechins, caffeine and theanine were analyzed by high performance liquid chromatography (HPLC)...
March 15, 2017: Food Chemistry
Delia Elena Urcan, Simone Giacosa, Fabrizio Torchio, Susana Río Segade, Stefano Raimondi, Marta Bertolino, Vincenzo Gerbi, Nastasia Pop, Luca Rolle
The impact of postharvest dehydration on the volatile composition of Malvasia moscata grapes and fortified wines produced from them was assessed. The ripeness effect of fresh grapes on volatile compounds of dehydrated grapes was evaluated for the first time in this study. Fresh grape berries were densimetrically sorted, and more represented density classes were selected. Dehydration of riper berries (20.5 °Brix) led to volatile profiles richer in terpenes, particularly linalool and geraniol. The effect of dehydration rate on the volatile composition of dehydrated grapes and fortified wines was also evaluated...
March 15, 2017: Food Chemistry
Ramona Bosse Née Danz, Melanie Wirth, Annette Konstanz, Thomas Becker, Jochen Weiss, Monika Gibis
A simple, reliable and automated method was developed and optimized for qualification and quantification of aroma-relevant volatile marker compounds of North European raw ham using a headspace (HS)-Trap gas chromatography-mass spectrometry (GC-MS) and GC-flame ionization detector (FID) analysis. A total of 38 volatile compounds were detected with this HS-Trap GC-MS method amongst which the largest groups were ketones (12), alcohols (8), hydrocarbons (7), aldehydes (6) and esters (3). The HS-Trap GC-FID method was optimized for the parameters: thermostatting time and temperature, vial and desorption pressure, number of extraction cycles and salt addition...
March 15, 2017: Food Chemistry
Thais M Uekane, Luca Nicolotti, Alessandra Griglione, Humberto R Bizzo, Patrizia Rubiolo, Carlo Bicchi, Maria Helena M Rocha-Leão, Claudia M Rezende
The volatile fraction of murici, bacuri and sapodilla are here studied because of their increasing interest for consumers, abundance of production in Brazil, and the general demand for new flavors and aromas. Their volatile profiles were studied by two High Concentration Capacity Headspace techniques (HCC-HS), Headspace Solid Phase Microextraction (HS-SPME) and Headspace Sorptive Extraction (HSSE), in combination with GC-MS. Murici volatile fraction mainly contains esters (38%), carboxylic acids (19%), aldehydes (11%), alcohols (14%), others (13%) and sulfur compounds; bacuri is characterized by terpenes (41%), non-terpenic alcohols (24%), esters (15%), aldehydes (6%), and others (12%); sapodilla consists of esters (33%), alcohols (27%), terpenes (18%) and others (21%)...
March 15, 2017: Food Chemistry
Jing Li, Tengfei Fan, Yong Xu, Xuemin Wu
Emulsifiers for pesticide microemulsions contain a part of volatile organic compounds (VOCs), and ionic liquids (ILs) are becoming potential substitutes. In order to apply ILs in pesticide microemulsions, the study of interaction between ILs and surfactants is necessary. Therefore, the surface properties and aggregation of anionic surfactant sodium dodecyl sulfate (SDS) in ILs, including N-hexyl-N-methylmorpholinyl bromide ([C6mm][Br]), N-hexyl-N-methylpiperidyl bromide ([C6mp][Br]), N-hexyl-N-methylpyrrolidyl bromide ([C6mpyr][Br]), N-octyl-N-methylpyrrolidyl bromide ([C8mpyr][Br]), N-dodecyl-N-methylpyrrolidyl bromide ([C12mpyr][Br]) and N-hexadecyl-N-methylpyrrolidyl bromide ([C16mpyr][Br]), were investigated in terms of surface tension, conductivity, dynamic light scattering (DLS), viscosity, fluorescence, pseudo-ternary phase diagram and (1)H NMR measurements...
October 19, 2016: Physical Chemistry Chemical Physics: PCCP
Nikolay Borodinov, Anna Paola Soliani, Yuriy Galabura, Bogdan Zdyrko, Carley Tysinger, Spencer Novak, Qingyang Du, Yizhong Huang, Vivek Singh, Zhaohong Han, Juejun Hu, Lionel Kimerling, Anuradha Murthy Agarwal, Kathleen Richardson, Igor Luzinov
We have fabricated gradient grafted nanofoam films that are able to record the presence of volatile chemical compounds in an off-line regime. In essence, the nanofoam film (100-300 nm thick) is anchored to a surface cross-linked polymer network in a metastable extended configuration that can relax back to a certain degree upon exposure to a chemical vapor. The level of the chain relaxation is associated with thermodynamic affinity between the polymer chains and the volatile compounds. In our design, the chemical composition of the nanofoam film is not uniform; therefore, the film possesses a gradually changing local affinity to a vapor along the surface...
October 18, 2016: ACS Nano
Laura Capelli, Gianluigi Taverna, Alessia Bellini, Lidia Eusebio, Niccolò Buffi, Massimo Lazzeri, Giorgio Guazzoni, Giorgio Bozzini, Mauro Seveso, Alberto Mandressi, Lorenzo Tidu, Fabio Grizzi, Paolo Sardella, Giuseppe Latorre, Rodolfo Hurle, Giovanni Lughezzani, Paolo Casale, Sara Meregali, Selena Sironi
The electronic nose is able to provide useful information through the analysis of the volatile organic compounds in body fluids, such as exhaled breath, urine and blood. This paper focuses on the review of electronic nose studies and applications in the specific field of medical diagnostics based on the analysis of the gaseous headspace of human urine, in order to provide a broad overview of the state of the art and thus enhance future developments in this field. The research in this field is rather recent and still in progress, and there are several aspects that need to be investigated more into depth, not only to develop and improve specific electronic noses for different diseases, but also with the aim to discover and analyse the connections between specific diseases and the body fluids odour...
October 14, 2016: Sensors
Yan-Lun Ju, Min Liu, Hui Zhao, Jiang-Fei Meng, Yu-Lin Fang
The anthocyanin composition, fatty acids, and volatile aromas are important for Cabernet Sauvignon grape quality. This study evaluated the effect of exogenous abscisic acid (ABA) and methyl jasmonate (MeJA) on the anthocyanin composition, fatty acids, lipoxygenase activity, and the volatile compounds of Cabernet Sauvignon grape berries. Exogenous ABA and MeJA improved the content of total anthocyanins (TAC) and individual anthocyanins. Lipoxygenase (LOX) activity also increased after treatment. Furthermore, 16 fatty acids were detected...
October 12, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Marika Rai, David Spratt, Paola R Gomez-Pereira, Jay Patel, Sean P Nair
Oral malodour is a common condition which affects a large proportion of the population, resulting in social, emotional and psychological stress. Certain oral bacteria form a coating called a biofilm on the tongue dorsum and degrade organic compounds releasing volatile sulfur compounds that are malodourous. Current chemical treatments for oral malodour such as mouthwashes containing chlorhexidine or essential oils, are not sufficiently effective at reducing the bacterial load on the tongue. One potential alternative to current chemical treatments for oral malodour is the use of light activated antimicrobial agents (LAAAs), which display no toxicity or antimicrobial activity in the dark, but when exposed to light of a specific wavelength produce reactive oxygen species which induce damage to target cells in a process known as photodynamic inactivation...
October 18, 2016: Journal of Breath Research
Sang Pil Hong, Eun Joo Lee, Young Ho Kim, Dong Uk Ahn
This study was conducted to evaluate the effect of fermentation temperature on the volatile composition in Kimchi. Kimchi was fermented at 2 temperature conditions (4 and 20 °C). Volatile compounds of Kimchi samples were analyzed during the fermentation periods using the dynamic headspace gas chromatography-mass spectrometry method. The optimum ripening time for the Kimchi fermented at 4 °C was 35 d, and that of 20 °C was 2 d. The pH at the optimum ripening time was 4.97 and 4.41, and the titratable acidity was 0...
October 17, 2016: Journal of Food Science
Anandram Venkatasubramanian, Vincent T K Sauer, Swapan K Roy, Mike Xia, David S Wishart, Wayne K Hiebert
Micro-Gas Chromatography (GC) is promising for portable chemical analysis. We demonstrate a nano-optomechanical system (NOMS) as an ultrasensitive mass detector in gas chromatography. Bare, native oxide, silicon surfaces are sensitive enough to monitor volatile organic compounds at ppm levels, while simultaneously demonstrating chemical selectivity. The NOMS is able to sense GC peaks from derivatized metabolites at physiological concentrations. This is an important milestone for small-molecule quantitation assays in next generation metabolite analyses for applications such as disease diagnosis and personalized medicine...
October 17, 2016: Nano Letters
Guozhu Zhao, Guohua Yin, Arati A Inamdar, Jing Luo, Ning Zhang, Ill Yang, Brian Buckley, Joan W Bennett
Super Storm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to 8 genera: Penicillium (12 species), Fusarium (4 species), Aspergillus (3 species), Trichoderma (2 species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis...
October 17, 2016: Indoor Air
Carien Coetzee, Elizma Van Wyngaard, Katja Šuklje, Antonio C Silva Ferreira, Wessel J du Toit
The effect of repetitive controlled oxidation on the chemical and sensory composition of a fresh and fruity style Sauvignon blanc wine was investigated. Chemical analyses were conducted together with extensive sensory profiling. A decrease in volatile thiols responsible for the fruity nuances and an increase in oxidation-related compounds, such as acetaldehyde, during the course of the oxidation was observed. The wine evolved from a fresh and fruity one to one with slight oxidation and then developed extreme oxidative characteristics...
October 17, 2016: Journal of Agricultural and Food Chemistry
Kenion H Blakeman, Craig A Cavanaugh, William M Gilliland, J Michael Ramsey
RATIONALE: There are many chemical measurement scenarios that would benefit from hand portable mass spectrometry tools including forensics, environmental monitoring, and safety and security. High pressure mass spectrometry (HPMS) facilitates miniaturization by significantly reducing vacuum system requirements. Previous work demonstrated HPMS using helium buffer gas, but HPMS conducted using ambient air would further reduce the size and weight of a portable instrument while also reducing logistical demands by eliminating the need for a helium supply...
October 17, 2016: Rapid Communications in Mass Spectrometry: RCM
Charlie E Kivi, Datong Song
A new metal-organic framework (1) constructed from 4-(4-(3,5-dimethyl-1H-pyrazol-4-yl)phenyl)pyridine (HL) and CuBr shows potential as a luminescent sensor for volatile organic compounds.
October 17, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Tina Ilc, Danièle Werck-Reichhart, Nicolas Navrot
Wine aroma strongly influences wine quality, yet its composition and its evolution during the winemaking process are poorly understood. Volatile compounds that constitute wine aroma are traditionally divided into three classes according to their origin: grape, fermentation, and maturation aroma. We challenge this view with meta-analysis and review of grape and wine volatiles and their precursors from 82 profiling experiments. We compiled a list of 141 common grape and wine volatiles and quantitatively compared 43 of them...
2016: Frontiers in Plant Science
Jin-Lian Chen, Shi-Zhong Sun, Cui-Ping Miao, Kai Wu, You-Wei Chen, Li-Hua Xu, Hui-Lin Guan, Li-Xing Zhao
BACKGROUND: Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. METHODS: In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T...
October 2016: Journal of Ginseng Research
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