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https://www.readbyqxmd.com/read/28231176/volatile-composition-of-smoked-and-non-smoked-iranian-rice
#1
Leontina Lipan, Mohammad Hojjati, Hussein El-Zaeddi, Lucía Sánchez-Rodríguez, Ángel Antonio Carbonell-Barrachina
In this work, the volatile profiles of smoked and non-smoked Iranian rice were identified, and their relative abundance was calculated and compared. Headspace solid-phase microextraction together with gas chromatography-mass spectrometry (SPME-GC-MS) were used to extract and identify the volatile compounds. The main groups of volatiles in Iranian rice were aldehydes, ketones, phenol derivatives, furans, linear hydrocarbons, esters and terpenes. The chemical family aldehydes was the most abundant one in the profile of non-smoked rice, while phenol derivatives and furans predominated in smoked samples...
November 30, 2016: Foods (Basel, Switzerland)
https://www.readbyqxmd.com/read/28231164/essential-oil-characterization-of-thymus-vulgaris-from-various-geographical-locations
#2
Prabodh Satyal, Brittney L Murray, Robert L McFeeters, William N Setzer
Thyme (Thymus vulgaris L.) is a commonly used flavoring agent and medicinal herb. Several chemotypes of thyme, based on essential oil compositions, have been established, including (1) linalool; (2) borneol; (3) geraniol; (4) sabinene hydrate; (5) thymol; (6) carvacrol, as well as a number of multiple-component chemotypes. In this work, two different T. vulgaris essential oils were obtained from France and two were obtained from Serbia. The chemical compositions were determined using gas chromatography-mass spectrometry...
October 27, 2016: Foods (Basel, Switzerland)
https://www.readbyqxmd.com/read/28231151/increase-of-chamazulene-and-%C3%AE-bisabolol-contents-of-the-essential-oil-of-german-chamomile-matricaria-chamomilla-l-using-salicylic-acid-treatments-under-normal-and-heat-stress-conditions
#3
Mojtaba Ghasemi, Nadali Babaeian Jelodar, Mohammad Modarresi, Nadali Bagheri, Abbas Jamali
The chamazulene and α-(-)-bisabolol contents and quality of the chamomile oil are affected by genetic background and environmental conditions. Salicylic acid (SA), as a signaling molecule, plays a significant role in the plant physiological processes. The aim of this study was to evaluate the chemical profile, quantity, and improve the essential oil quality as a consequence of the increase of chamazulene and α-(-)-bisabol using salicylic acid under normal and heat stress conditions by the gas chromatography-mass spectrometry (GC-MS) technique...
August 27, 2016: Foods (Basel, Switzerland)
https://www.readbyqxmd.com/read/28231145/recent-advances-in-techniques-for-starch-esters-and-the-applications-a-review
#4
REVIEW
Jing Hong, Xin-An Zeng, Charles S Brennan, Margaret Brennan, Zhong Han
Esterification is one of the most important methods to alter the structure of starch granules and improve its applications. Conventionally, starch esters are prepared by conventional or dual modification techniques, which have the disadvantages of being expensive, have regent overdoses, and are time-consuming. In addition, the degree of substitution (DS) is often considered as the primary factor in view of its contribution to estimate substituted groups of starch esters. In order to improve the detection accuracy and production efficiency, different detection techniques, including titration, nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis/infrared spectroscopy (TGA/IR) and headspace gas chromatography (HS-GC), have been developed for DS...
July 9, 2016: Foods (Basel, Switzerland)
https://www.readbyqxmd.com/read/28231136/volatile-composition-of-essential-oils-from-different-aromatic-herbs-grown-in-mediterranean-regions-of-spain
#5
Hussein El-Zaeddi, Juan Martínez-Tomé, Ángel Calín-Sánchez, Francisco Burló, Ángel A Carbonell-Barrachina
Volatile composition of essential oils from dill, parsley, coriander, and mint were investigated at different harvest dates to determine the most suitable harvest time for each these herbs. Hydrodistillation (HD), using a Deryng system, was used for isolating the essential oils. Isolation and identification of the volatile compounds were performed using gas chromatography-mass spectrometry (GC-MS) instrument. The results of gas chromatography-flame ionization detector (GC-FID) analysis (quantification) showed that the main components in the essential oil of dill shoots were α-phellandrene, dill ether, and β-phellandrene, and the optimal harvest date was D2 (second harvest, fourth week of February 2015)...
May 25, 2016: Foods (Basel, Switzerland)
https://www.readbyqxmd.com/read/28231089/identification-of-aroma-compounds-of-lamiaceae-species-in-turkey-using-the-purge-and-trap-technique
#6
Ahmet Salih Sonmezdag, Hasim Kelebek, Serkan Selli
The present research was planned to characterize the aroma composition of important members of the Lamiaceae family such as Salvia officinalis, Lavandula angustifolia and Mentha asiatica. Aroma components of the S. officinalis, L. angustifolia and M. asiatica were extracted with the purge and trap technique with dichloromethane and analyzed with the gas chromatography-mass spectrometry (GC-MS) technique. A total of 23, 33 and 33 aroma compounds were detected in Salvia officinalis, Lavandula angustifolia and Mentha asiatica, respectively including, acids, alcohols, aldehydes, esters, hydrocarbons and terpenes...
February 8, 2017: Foods (Basel, Switzerland)
https://www.readbyqxmd.com/read/28230979/simple-expendable-3d-printed-microfluidic-systems-for-sample-preparation-of-petroleum
#7
Erica Megumi Kataoka, Rui Cesar Murer, Jandyson Machado Santos, Rogerio Mesquita de Carvalho, Marcos Nogueira Eberlin, Fabio Augusto, Ronei Jesus Poppi, Angelo Luiz Gobbi, Leandro Wang Hantao
In this study, we introduce a simple protocol to manufacture disposable, 3D-printed microfluidic systems for sample preparation of petroleum. Such platform is produced with a consumer-grade 3D-printer, using fused deposition modeling. Successful incorporation of solid-phase extraction (SPE) to microchip was ensured by facile 3D element integration using proposed approach. This 3D-printed μSPE device was applied to challenging matrices in oil & gas industry, such as crude oil and oil-brine emulsions. Case studies investigated important limitations of non-silicon and non-glass microchips, namely, resistance to nonpolar solvents and conservation of sample integrity...
February 23, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28230323/simultaneous-determination-of-seven-nitrogen-containing-phenyl-ethers-in-cosmetics-by-gas-chromatography-with-mass-spectrometry-and-dispersive-solid-phase-extraction
#8
Jiale Huang, Langjun Zhou, Zhiqing Xun, Qiang Wang, Senyu Lin, Xindong Guo, Yongtong Cai
An analytical method was established for the simultaneous determination of seven nitrogen-containing phenyl ethers (2-anisidine, 3-anisidine, 4-anisidine, 2-nitroanisole, 3-nitroanisole, 4-nitroanisole and 3,3'-dimethoxybenzidine) in cosmetics by gas chromatography with mass spectrometry in this work. The samples were extracted with ethyl acetate and purified with primary secondary amine during the dispersed solid phase extraction. The analytes were separated by a DB-17MS column and detected in the electron ionization mode of mass spectrometry in the selected ions monitoring mode...
February 23, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28228752/intestinal-microbiota-and-weight-gain-in-preterm-neonates
#9
Silvia Arboleya, Pablo Martinez-Camblor, Gonzalo Solís, Marta Suárez, Nuria Fernández, Clara G de Los Reyes-Gavilán, Miguel Gueimonde
The involvement of the gut microbiota on weight-gain and its relationship with childhood undernutrition and growth has been reported. Thus, the gut microbiota constitutes a potential therapeutic target for preventing growth impairment. However, our knowledge in this area is limited. In this study we aimed at evaluating the relationship among early microbiota, growth, and development in preterm infants. To this end we assessed the levels of specific microorganisms by qPCR, and those of short chain fatty acids by mean of gas-chromatography, in feces from 63 preterm newborns and determined their weight-gain during the first months...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28228233/analyzing-complex-mixtures-of-drug-like-molecules-ion-mobility-as-an-adjunct-to-existing-liquid-chromatography-tandem-mass-spectrometry-methods
#10
Jasper Boschmans, Filip Lemière, Frank Sobott
The use of traveling wave ion mobility mass spectrometry (TWIMS) is evaluated in conjunction with, and as a possible alternative to, conventional LC-MS(/MS) methods for the separation and characterization of drug-like compounds and metabolites. As a model system we use an in vitro incubation mixture of the chemotherapeutic agent melphalan, which results in more than ten closely related hydrolysis products and chain-like oligomers. Ion mobility as a filtering tool results in the separation of ions of interest from interfering ions, based on charge state and shape/size...
February 14, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28225098/urinary-metabolic-signatures-and-early-triage-of-acute-radiation-exposure-in-rat-model
#11
Mingxiao Zhao, Kim Kt Lau, Xian Zhou, Jianfang Wu, Jun Yang, Chang Wang
After a large-scale radiological accident, early-response biomarkers to assess radiation exposure over a broad dose range are not only the basis of rapid radiation triage, but are also the key to the rational use of limited medical resources and to the improvement of treatment efficiency. Because of its high throughput, rapid assays and minimally invasive sample collection, metabolomics has been applied to research into radiation exposure biomarkers in recent years. Due to the complexity of radiobiological effects, most of the potential biomarkers are both dose-dependent and time-dependent...
February 22, 2017: Molecular BioSystems
https://www.readbyqxmd.com/read/28224911/determination-of-total-cyanide-in-soil-by-isotope-dilution-gc-ms-following-pentafluorobenzyl-derivatization
#12
Beatrice Campanella, Lorenzo Biancalana, Lucia D'Ulivo, Massimo Onor, Emilia Bramanti, Zoltan Mester, Enea Pagliano
The high toxicity of cyanide, along with its widespread industrial use, has fuelled interest in the development of analytical methods for its determination in complex matrices. In this study, we propose a novel approach for the measurement of total cyanide in soil samples based on single-step derivatization with pentafluorobenzyl bromide (F5Bn-Br) followed by quantitation with gas chromatography mass spectrometry in negative chemical ionization mode. The reaction between CN(-) and F5Bn-Br resulted in the identification of several derivatives such as F5Bn-CN, (F5Bn)(F5Ph)CH-CN, and (F5Bn)2(F5Ph)C-CN...
April 8, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28224907/multi-block-data-analysis-using-comdim-for-the-evaluation-of-complex-samples-characterization-of-edible-oils
#13
Larissa Naida Rosa, Luana Caroline de Figueiredo, Elton Guntendorfer Bonafé, Aline Coqueiro, Jesuí Vergílio Visentainer, Paulo Henrique Março, Douglas N Rutledge, Patrícia Valderrama
The ComDim chemometrics method for multi-block analysis was employed to evaluate thirty-two vegetable oil samples analyzed by near infrared (NIR) and ultraviolet-visible (UV-Vis) spectroscopy, and by Gas Chromatography with flame ionization detection (GC-FID) for their fatty acids composition. This unsupervised pattern recognition method was able to extract information from the tables of results that could be presented in informative graphs showing the relationship between the samples through the scores, the predominance of information in particular tables through the saliences and the contribution of the variables in each table which were responsible for the similarities observed in the samples, through the loadings plots...
April 8, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28224154/unexpectedly-high-concentrations-of-monoterpenes-in-a-study-of-uk-homes
#14
Chunting Michelle Wang, Benjamin Barratt, Nicola Carslaw, Artemis Doutsi, Rachel E Dunmore, Martyn W Ward, Alastair C Lewis
The abundance of volatile organic compounds (VOCs) found in homes depends on many factors such as emissions, ventilation and the oxidative environment and these are evolving over time, reflecting changes in chemical use, behaviour and building design/materials. The concentrations of VOCs in 25 UK homes of varying ages, design and occupancy were quantified using continuous indoor air sampling over five days. Air was collected through low flow (1 mL min(-1)) constant flow restrictors into evacuated 6 L internally silica-treated canisters until the canisters reached atmospheric pressure...
February 22, 2017: Environmental Science. Processes & Impacts
https://www.readbyqxmd.com/read/28223976/plant-growth-promotion-by-volatile-organic-compounds-produced-by-bacillus-subtilis-syst2
#15
Hafiz A S Tahir, Qin Gu, Huijun Wu, Waseem Raza, Alwina Hanif, Liming Wu, Massawe V Colman, Xuewen Gao
Bacterial volatiles play a significant role in promoting plant growth by regulating the synthesis or metabolism of phytohormones. In vitro and growth chamber experiments were conducted to investigate the effect of volatile organic compounds (VOCs) produced by the plant growth promoting rhizobacterium Bacillus subtilis strain SYST2 on hormone regulation and growth promotion in tomato plants. We observed a significant increase in plant biomass under both experimental conditions; we observed an increase in photosynthesis and in the endogenous contents of gibberellin, auxin, and cytokinin, while a decrease in ethylene levels was noted...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28223975/characterization-of-a-novel-polymeric-bioflocculant-produced-from-bacterial-utilization-of-n-hexadecane-and-its-application-in-removal-of-heavy-metals
#16
Mihirjyoti Pathak, Hridip K Sarma, Krishna G Bhattacharyya, Sanjukta Subudhi, Varsha Bisht, Banwari Lal, Arundhuti Devi
A novel polymeric bioflocculant was produced by a bacterium utilizing degradation of n-hexadecane as the energy source. The bioflocculant was produced with a bioflocculating activity of 87.8%. The hydrocarbon degradation was confirmed by gas chromatography-mass spectrometry analysis and was further supported with contact angle measurements for the changes in hydrophobic nature of the culture medium. A specific aerobic degradation pathway followed by the bacterium during the bioflocculant production and hydrocarbon utilization process has been proposed...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28222414/urinary-steroid-metabolites-in-a-case-of-florid-ectopic-cushing-s-syndrome-and-clinical-correlations
#17
Angelos Kyriacou, Karolina G Stepien, Basil Issa
A 51-year old woman was admitted with multiple cerebral, pulmonary and intra-abdominal abscesses. The combination of apparent immunosuppression, obesity, diabetes mellitus, hypertension, hypokalaemia, osteoporotic fractures and bilateral shoulder avascular necrosis led to a clinical diagnosis of Cushing's syndrome (CS). This was biochemically confirmed as follows: midnight serum cortisol 4275 nmol/L (60-250), non-suppressed overnight dexamethasone suppression test, raised salivary cortisol 716 nmol/L (5-46) and ACTH 639 ng/L (0-46)...
October 2016: Hormones: International Journal of Endocrinology and Metabolism
https://www.readbyqxmd.com/read/28222171/metabolite-profiling-of-the-carnivorous-pitcher-plants-darlingtonia-and-sarracenia
#18
Hannu Hotti, Peddinti Gopalacharyulu, Tuulikki Seppänen-Laakso, Heiko Rischer
Sarraceniaceae is a New World carnivorous plant family comprising three genera: Darlingtonia, Heliamphora, and Sarracenia. The plants occur in nutrient-poor environments and have developed insectivorous capability in order to supplement their nutrient uptake. Sarracenia flava contains the alkaloid coniine, otherwise only found in Conium maculatum, in which its biosynthesis has been studied, and several Aloe species. Its ecological role and biosynthetic origin in S. flava is speculative. The aim of the current research was to investigate the occurrence of coniine in Sarracenia and Darlingtonia and to identify common constituents of both genera, unique compounds for individual variants and floral scent chemicals...
2017: PloS One
https://www.readbyqxmd.com/read/28221876/effect-of-magnesium-acetate-on-the-antimold-activity-of-lactobacillus
#19
Katarzyna Kycia, Anna Bzducha-Wróbel, Karolina Kraśniewska, Anna Chlebowska-Śmigiel, Małgorzata Gniewosz
The antimold activity of lactic acid bacteria (LAB) is used in food biopreservation. The aim of this study was to evaluate the effect of magnesium acetate added to de Man Rogosa Sharpe (MRS) medium on the antimold activity of three LAB strains ( Lactobacillus plantarum , Lactobacillus brevis , and Lactobacillus fermentum ) against molds contaminating food ( Aspergillus oryzae , Aspergillus niger , Penicillium chrysogenum , Fusarium avenaceum , and Rhizopus arrhizus ) and their ability to produce organic acids (acetic acid, lactic acid, and phenyllactic acid)...
January 2017: Journal of Food Protection
https://www.readbyqxmd.com/read/28221781/the-relationship-between-organic-loading-and-effects-on-fish-reproduction-for-pulp-mill-effluents-across-canada
#20
Pierre H Martel, Brian I O'Connor, Tibor G Kovacs, Michael R Van Den Heuvel, Joanne L Parrott, Mark E McMaster, Deborah L MacLatchy, Glen J Van Der Kraak, L Mark Hewitt
This study builds upon the work of a multiagency consortium tasked with determining cost effective solutions for the effects of pulp mill effluents on fish reproduction. A laboratory fathead minnow egg production test and chemical characterization tools were used to benchmark eighty-one effluents from twenty mills across Canada, representing the major pulping, bleaching and effluent treatment technologies. For Kraft and mechanical pulp mills, effluents containing less than 20 mg/L BOD5 were found to have the greatest probability of having no effects...
February 21, 2017: Environmental Science & Technology
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