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https://www.readbyqxmd.com/read/28346994/gc-ms-analysis-and-potential-cytotoxic-activity-of-calyptranthes-grandifolia-o-berg-calyptranthes-tricona-d-legrand-and-myrciaria-plinioides-d-legrand-essential-oil-in-raw264-7-and-cho-k1-cells
#1
D Faleiro, S M Immich, F Majolo, L Mayer, E M Ethur, M I Goettert
The search for new bioactive substances derived from natural products is daily growing. Among biologically active products used in therapeutic approaches, essential oils are described with wide range of therapeutic and pharmacological potential. Plants from Myrtaceae family have the presence of essential oils in its composition. Calyptranthes grandifolia, Calyptranthes tricona and Myrciaria plinioides species belong to this family and are used by the local population. However, there are no reports in the literature describing relevant characteristics about the potential and possible activities of these species...
March 22, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28346061/understanding-the-contamination-of-food-with-mineral-oil-the-need-for-a-confirmatory-analytical-and-procedural-approach
#2
Lionel W Spack, Gabriela Leszczyk, Jesus Varela, Hervé Simian, Thomas Gude, Richard H Stadler
The contamination of food by mineral oil hydrocarbons (MOH) found in packaging is a long running concern. A main source of MOH in foods is the migration of mineral oil from recycled board into the packed food products. Consequently, the majority of food manufacturers have taken protective measures, for example by using virgin board instead of recycled fibers, and where feasible, introducing functional barriers to mitigate migration. Despite these protective measures, MOH may still be observed at low amounts in certain food products, albeit due to different entry points across the food supply chain...
March 27, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28345909/rapid-and-simultaneous-analysis-of-360-pesticides-in-brown-rice-spinach-orange-and-potato-using-microbore-gc-ms-ms
#3
Jonghwa Lee, Leesun Kim, Yongho Shin, Junghak Lee, Jiho Lee, Eunhye Kim, Joon-Kwan Moon, Jeong-Han Kim
A multi-residue method for simultaneous and rapid analysis of 360 pesticides in representative agricultural produce (brown rice, orange, spinach, and potato) was developed using a modified QuEChERS procedure combined with gas chromatography tandem mass spectrometry (GC-MS/MS). Selected reaction monitoring transition parameters (e.g., collision energy, precursor and product ions) in MS/MS were optimized to achieve the best selectivity and sensitivity for a wide range of GC amenable pesticides. A short (20 m) microbore (0...
March 27, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28345701/the-effect-of-natural-iron-oxide-and-oxalic-acid-on-the-photocatalytic-degradation-of-isoproturon-a-kinetics-and-analytical-study
#4
H Boucheloukh, W Remache, F Parrino, T Sehili, H Mechakra
The photocatalytic degradation of isoproturon, a persistent toxic herbicide, was investigated in the presence of natural iron oxide and oxalic acid and under UV irradiation. The influence of the relevant parameters such as the pH and the iron oxide and oxalic acid concentrations has been studied. The presence of natural iron oxide and oxalic acid in the system effectively allow the degradation of isoproturon, whereas the presence of t-butyl alcohol adversely affects the phototransformation of the target pollutant, thus indicating that an OH radical initiated the degradation mechanism...
March 27, 2017: Photochemical & Photobiological Sciences
https://www.readbyqxmd.com/read/28345447/urea-enhances-cell-lysis-of-schizosaccharomyces-pombe-ura4-mutants
#5
Kohei Nishino, Misaki Kushima, Tomohiro Kaino, Yasuhiro Matsuo, Makoto Kawamukai
Cell lysis is induced in Schizosaccharomyces pombe ∆ura4 cells grown in YPD medium, which contains yeast extract, polypeptone, and glucose. To identify the medium components that induce cell lysis, we first tested various kinds of yeast extracts from different suppliers. Cell lysis of ∆ura4 cells on YE medium was observed when yeast extracts from OXOID, BD, Oriental, and Difco were used, but not when using yeast extract from Kyokuto. To determine which compounds induced cell lysis, we subjected yeast extract and polypeptone to GC-MS analysis...
March 27, 2017: Bioscience, Biotechnology, and Biochemistry
https://www.readbyqxmd.com/read/28345380/comparative-study-of-ultraviolet-laser-based-time-resolved-photoacoustic-fingerprint-spectra-and-thermal-decomposition-mechanisms-of-energetic-1-2-3-1h-triazole-derivatives-under-controlled-pyrolysis
#6
Konda Srinivasa Rao, Anil Kumar Chaudhary
We report the comparative study of photoacoustic (PA) fingerprint spectra, thermal decomposition, and stability mechanism of some phenyl and bis series energetic compounds named 1-(2-methoxy,-3,5-dinitrophenyl)-1H-1,2,3-triazole ( S5), 1-(3-methoxy, 2, 6 dinitrophenyl) 1H-1, 2, 3 triazole ( S10), 1-(4-nitrophenyl)-1H-1,2,3-triazole ( S8), and 2,6-bis ((4-(nitromethyl)-1H-1,2,3-triazol-1-yl)methyl) pyridine ( S9). Fourth harmonic wavelength, i.e., 266 nm of pulse duration 7 ns and 10 Hz repetition rate obtained from Q-switched Nd: YAG laser, was used to record the thermal PA spectra of these compounds under controlled pyrolysis condition in the range of 30-350 ℃...
January 1, 2017: Applied Spectroscopy
https://www.readbyqxmd.com/read/28344493/volatile-constituents-and-biological-activities-of-the-leaf-and-root-of-echinacea-species-from-south-africa
#7
M Nyalambisa, I A Oyemitan, R Matewu, O O Oyedeji, O S Oluwafemi, S P Songca, B N Nkeh-Chungag, A O Oyedeji
Echinacea is used ethnomedicinally for the treatment of various diseases such as cough, respiratory infections, and bronchitis among other uses in Eastern Cape region of South Africa. This study evaluated the volatile components of the essential oil of the plant, its toxicity, anti-inflammatory and analgesic activities in rodents. Dried leaf and root of the plant were separately processed by hydrodistillation for 4 h and their essential oils (EOs) were collected. Extracted oils were subjected to GC/GC-MS analysis...
March 2017: Saudi Pharmaceutical Journal: SPJ: the Official Publication of the Saudi Pharmaceutical Society
https://www.readbyqxmd.com/read/28343387/hydroxyl-and-methoxyl-derivatives-of-benzylglucosinolate-in-lepidium-densiflorum-with-hydrolysis-to-isothiocyanates-and-non-isothiocyanate-products-substitution-governs-product-type-and-mass-spectral-fragmentation
#8
Eleonora Pagnotta, Niels Agerbirk, Carl Erik Olsen, Luisa Ugolini, Susanna Cinti, Luca Lazzeri
A system of benzylic glucosinolates was found and characterized in common pepperweed, Lepidium densiflorum Schrad. The major glucosinolate was the novel 4-hydroxy-3,5-dimethoxybenzylglucosinolate (3,5-dimethoxysinalbin), present at high levels in seeds, leaves and roots. Medium level glucosinolates were 3,4-dimethoxybenzylglucosinolate and 3,4,5-trimethoxybenzylglucosinolate. Minor glucosinolates included benzylglucosinolate, 3-hydroxy and 3-methoxybenzylglucosinolate, 4-hydroxybenzylglucosinolate (sinalbin), the novel 4-hydroxy-3-methoxybenzylglucosinolate (3-methoxysinalbin) and indole-type glucosinolates...
March 25, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28343386/characterization-of-the-potent-odorants-contributing-to-the-characteristic-aroma-of-matcha-by-gas-chromatography-olfactometry-techniques
#9
Ryoko Baba, Yohei Amano, Yoshiyuki Wada, Kenji Kumazawa
The odorants contributing to the characteristic aroma of Matcha were investigated by analysis of the headspace samples and the volatile fractions prepared by a combination of solvent extraction and the SAFE techniques using three Matcha powders of different grades (high, medium, and low). Gas chromatography-olfactometry of the headspace samples (GCO-H) and the aroma extract dilution analysis (AEDA) applied to the volatile fractions revealed 16 (FD factor ≥1) and 39 (FD factor ≥4(3)) odor-active peaks, respectively...
March 25, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28343038/physicochemical-characterization-of-ambient-pm2-5-in-tehran-air-and-its-potential-cytotoxicity-in-human-lung-epithelial-cells-a549
#10
Anoushiravan MohseniBandpi, Akbar Eslami, Abbas Shahsavani, Fariba Khodagholi, Abdolazim Alinejad
As air pollution is a major problem in Tehran, this study aimed to investigate the physicochemical characterization of the water-soluble and organic contents of ambient PM2.5 in Tehran and determine its in vitro toxicological impact on human lung epithelial cells (A549). A total of 11 sampling stations were selected, including three categories: traffic, urban, and suburban. All sampling was carried out in the spring and summer of 2015. Ion chromatography (IC), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and GC-MS were used to analyze ionic compounds, heavy metals, and polycyclic aromatic hydrocarbons (PAHs), respectively, and an ELISA reader was used for cytotoxicity analysis...
March 23, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28342584/dispersive-liquid-liquid-microextraction-and-injection-port-derivatization-for-the-determination-of-free-lipophilic-compounds-in-fruit-juices-by-gas-chromatography-mass-spectrometry
#11
Alexis Marsol-Vall, Mercè Balcells, Jordi Eras, Ramon Canela-Garayoa
A method consisting of dispersive liquid-liquid microextraction (DLLME) followed by injection-port derivatization and gas chromatography-mass spectrometry (GC-MS) for the analysis of free lipophilic compounds in fruit juices is described. The method allows the analysis of several classes of lipophilic compounds, such as fatty acids, fatty alcohols, phytosterols and triterpenes. The chromatographic separation of the compounds was achieved in a chromatographic run of 25.5min. The best conditions for the dispersive liquid-liquid microextraction were 100μL of CHCl3 in 1mL of acetone...
March 18, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28342345/use-of-exhaled-air-as-an-improved-biomonitoring-method-to-assess-perchloroethylene-short-term-exposure
#12
Cláudia M Dias, Helvécio C Menezes, Zenilda L Cardeal
This paper shows the use of exhaled air as a biomonitoring method to assess perchloroethylene (PERC) environmental and occupational exposure. A sensitive, fast, and solvent free analytical method was developed to determine PERC in ambient and exhaled air of individuals occupationally exposed. The developed method used cold fiber solid phase microextraction (CF-SPME) as the sampling technique, and a standard permeation method to simulation of air matrix. The analysis were conducted by gas chromatography coupled to mass spectrometry (GC/MS)...
March 22, 2017: Environmental Research
https://www.readbyqxmd.com/read/28342193/metabolism-of-the-tryptamine-derived-new-psychoactive-substances-5-meo-2-me-dalt-5-meo-2-me-alcht-and-5-meo-2-me-dipt-and-their-detectability-in-urine-studied-by-gc-ms-lc-ms-n-and-lc-hr-ms-ms
#13
Achim T Caspar, Jonas B Gaab, Julian A Michely, Simon D Brandt, Markus R Meyer, Hans H Maurer
Many N,N-dialkylated tryptamines show psychoactive properties and were encountered as new psychoactive substances. The aims of the presented work were to study the phase I and II metabolism and the detectability in standard urine screening approaches (SUSA) of 5-methoxy-2-methyl-N,N-diallyltryptamine (5-MeO-2-Me-DALT), 5-methoxy-2-methyl-N-allyl-N-cyclohexyltryptamine (5-MeO-2-Me-ALCHT), and 5-methoxy-2-methyl-N,N-diisopropyltryptamine (5-MeO-2-Me-DIPT) using GC-MS, LC-MS(n) , and LC-HR-MS/MS. For metabolism studies, urine was collected over a 24-h period after administration of the compounds to male Wistar rats at 20 mg/kg body weight (BW)...
March 24, 2017: Drug Testing and Analysis
https://www.readbyqxmd.com/read/28342178/return-of-the-lysergamides-part-iii-analytical-characterization-of-n-6-ethyl-6-norlysergic-acid-diethylamide-eth-lad-and-1-propionyl-eth-lad-1p-eth-lad
#14
Simon D Brandt, Pierce V Kavanagh, Folker Westphal, Simon P Elliott, Jason Wallach, Alexander Stratford, David E Nichols, Adam L Halberstadt
The psychoactive properties of lysergic acid diethylamide (LSD) have fascinated scientists across disciplines and the exploration of other analogs and derivatives has been motivated by deepening the understanding of ligand-receptor interactions at the molecular level as well as by the search for new therapeutics. Several LSD congeners have appeared on the new psychoactive substances (NPS) market in the form of blotters or powders. Examples include 1-propionyl-LSD (1P-LSD), AL-LAD and LSZ. The absence of analytical data for novel compounds is a frequent challenge encountered in clinical and toxicological investigations...
March 24, 2017: Drug Testing and Analysis
https://www.readbyqxmd.com/read/28341595/systems-characterization-of-differential-plasma-metabolome-perturbations-following-thrombotic-and-non-thrombotic-myocardial-infarction
#15
Patrick J Trainor, Bradford G Hill, Samantha M Carlisle, Eric C Rouchka, Shesh N Rai, Aruni Bhatnagar, Andrew P DeFilippis
Myocardial infarction (MI) is an acute event characterized by myocardial necrosis. Thrombotic MI is caused by spontaneous atherosclerotic plaque disruption that results in a coronary thrombus; non-thrombotic MI occurs secondary to oxygen supply-demand mismatch. We sought to characterize the differential metabolic perturbations associated with these subtypes utilizing a systems approach. Subjects presenting with thrombotic MI, non-thrombotic MI and stable coronary artery disease (CAD) were included. Whole blood was collected at two acute time-points and at a time-point representing the quiescent stable disease state...
March 21, 2017: Journal of Proteomics
https://www.readbyqxmd.com/read/28340770/a-novel-polyaniline-polypyrrole-graphene-oxide-fiber-for-the-determination-of-volatile-organic-compounds-in-headspace-gas-of-lung-cell-lines
#16
JingHong Li, Hui Xu
Exploration of volatile organic compounds (VOCs) generated by lung cell lines is a powerful and non-invasive tool for the detection of potential volatile biomarkers of lung cancer. In this study, a simple and sensitive solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) method was developed for the determination of VOCs in the headspace gas of lung cell lines. For the purpose of preconcentration, a novel polyaniline/polypyrrole/graphene oxide (PANI/PPy/GO) coating was prepared on the surface of stainless steel fiber via in-situ electrochemical deposition for the first time...
May 15, 2017: Talanta
https://www.readbyqxmd.com/read/28340758/versatile-magnetic-carbon-nanotubes-for-sampling-and-pre-concentration-of-pesticides-in-environmental-water
#17
Frederico Hayala Fernandes Barbosa, Helvécio Costa Menezes, Ana Paula de Carvalho Teixeira, Philippe Serp, Vitor Antipoff, Zenilda de Lourdes Cardeal
This article describes a simple, efficient, and versatile magnetic carbon nanotubes (MCNT) method for sampling and pre-concentration of pesticides in environmental water samples. The multi-walled magnetic carbon nanotubes were obtained by chemical deposition vapor (CVD) process. The MCNTs structures are formed of hydrophobic and hydrophilic fractions that provide great dispersion at any water matrix allowing simultaneously a high efficiency of pesticides sorption. Following the extraction, analytes were desorbed with minor amounts of solvent and analyzed by gas chromatography coupled mass spectrometry (GC/MS)...
May 15, 2017: Talanta
https://www.readbyqxmd.com/read/28340481/metabolic-profiling-of-tyrosine-tryptophan-and-glutamate-in-human-urine-using-gas-chromatography-tandem-mass-spectrometry-combined-with-single-spe-cleanup
#18
Hyun Ju Shin, Na Hyun Park, Wonwoong Lee, Man Ho Choi, Bong Chul Chung, Jongki Hong
The tyrosine, tryptophan, and glutamate metabolic pathways play key roles on pathological state of neuronal functions and the change of their levels in biological systems reflects the progress degree of neuronal diseases. Comprehensive profiling of these metabolites is important to find new biomarkers for diagnosis or prognosis of various neuronal diseases. However, the overall profiling analysis of various neurochemicals in biological sample is confronted with several limitations due to their low concentration and physicochemical properties and the coexistence of matrices...
March 16, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28340309/analytical-techniques-in-lipidomics-state-of-the-art
#19
Kamil Jurowski, Kamila Kochan, Justyna Walczak, Małgorzata Barańska, Wojciech Piekoszewski, Bogusław Buszewski
Current studies related to lipid identification and determination, or lipidomics in biological samples, are one of the most important issues in modern bioanalytical chemistry. There are many articles dedicated to specific analytical strategies used in lipidomics in various kinds of biological samples. However, in such literature, there is lack of articles dedicated to a comprehensive review of the actual analytical methodologies used in lipidomics. The aim of this article is to characterize the lipidomics methods used in modern bioanalysis according to the methodological point of view: 1) chromatography/separation methods, 2) spectroscopic methods and 3) mass spectrometry and also hyphenated methods...
March 24, 2017: Critical Reviews in Analytical Chemistry
https://www.readbyqxmd.com/read/28338346/chemical-variability-in-essential-oils-from-ruta-species-among-seasons-and-its-taxonomic-and-ecological-significance
#20
Zineb Bennaoum, Hachemi Benhassaini, Danilo Falconieri, Alessandra Piras, Silvia Porcedda
Leaf essential oils of 11 samples from Ruta montana, Ruta chalepensis subsp. latifolia and Ruta chalepensis subsp. angustifolia collected from two sites have been studied by GC/MS that allowed to identify 22, 25 and 12 components, respectively. The variability in the composition of essential oils among species and seasons was very high, and hence the existence of different chemotypes has been inferred. The major components were 2-undecanone, (E) caryophyllene, 2-nonanone and 2-methyloctyl acetate. Multivariate analysis of the 11 samples suggest that the main factors capable to influence the chemical composition of leaf essential oils was both the collection period and the geographical origin...
March 24, 2017: Natural Product Research
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