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https://www.readbyqxmd.com/read/29783172/headspace-sorptive-extraction-gas-chromatography-mass-spectrometry-method-to-measure-volatile-emissions-from-human-airway-cell-cultures
#1
Mei S Yamaguchi, Mitchell M McCartney, Angela L Linderholm, Susan E Ebeler, Michael Schivo, Cristina E Davis
The human respiratory tract releases volatile metabolites into exhaled breath that can be utilized for noninvasive health diagnostics. To understand the origin of this metabolic process, our group has previously analyzed the headspace above human epithelial cell cultures using solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). In the present work, we improve our model by employing sorbent-covered magnetic stir bars for headspace sorptive extraction (HSSE). Sorbent-coated stir bar analyte recovery increased by 52 times and captured 97 more compounds than SPME...
May 12, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29783146/gas-chromatographic-mass-spectrometric-characterization-of-thebaol-an-opium-constituent-and-its-structural-analogs
#2
Levan Megutnishvili, Nino Todua, Stephen Stein, Anzor Mikaia
A GC-MS method is described for the characterization of thebaol, a component of opium poppy. The method includes preliminary sample derivatization to TMS, TBDMS, TFA, PFP and HFB substituted products. Fragmentation of resulting derivatives is unique under electron ionization, and proceeds via consecutive loss of two radicals that violate the "even-electron rule". Peaks of [M-2CH3 ]+. and [M-C4 H9 -CH3 ]+. ions show maximum intensities in the spectra of trimethyl- and tert-butyldimethylsilyl-thebaols...
May 18, 2018: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29783096/all-roads-lead-to-rome-towards-understanding-different-avenues-of-tolerance-to-huanglongbing-in-citrus-cultivars
#3
Nabil Killiny, Shelley E Jones, Yasser Nehela, Faraj Hijaz, Manjul Dutt, Frederick G Gmitter, Jude W Grosser
Citrus tolerance to huanglongbing could result from tolerance to the pathogen Candidatus Liberibacter asiaticus (CLas) and/or to its vector Diaphorina citri. Field observations and greenhouse-controlled studies showed that some citrus cultivars were more tolerant than others. However, the mechanism(s) behind the tolerance has not been determined yet. Using GC-MS, we investigated the volatile organic compounds (VOCs) and the non-volatile metabolite profiles of two tolerant citrus cultivars- Australian finger lime, 'LB8-9' Sugar Belle® mandarin hybrid, and a recently released mandarin hybrid 'Bingo'...
May 18, 2018: Plant Physiology and Biochemistry: PPB
https://www.readbyqxmd.com/read/29783056/treatment-of-winery-wastewater-by-anodic-oxidation-using-bdd-electrode
#4
Christian Candia-Onfray, Nicole Espinoza, Evanimek B Sabino da Silva, Carla Toledo-Neira, L Carolina Espinoza, Rocío Santander, Verónica García, Ricardo Salazar
The effective removal of organics from winery wastewater was obtained in real residual effluents from the wine industry using anodic oxidation (AO). The effluent had an initial organic load of [COD]0 of 3490 mg L-1 equal to [TOC]0 of 1320 mg L-1 . In addition, more than 40 organic compounds were identified by means of GC-MS. Different density currents as well as the addition of electrolytes were tested during electrolysis. The results show the decay of [COD]t by 63.6% when no support electrolyte was added, whereas almost total mineralization and disinfection was reached after adding of 50 mM of sodium sulfate and sodium chloride and applying higher density currents...
May 4, 2018: Chemosphere
https://www.readbyqxmd.com/read/29782863/analysis-of-mulberry-leaf-components-in-the-treatment-of-diabetes-using-network-pharmacology
#5
Qi Ge, Liang Chen, Min Tang, Shu Zhang, Lu Gao, Shangshang Ma, Lanlan Liu, Ming Kong, Qin Yao, Keping Chen, Fan Feng
Mulberry leaves are one of the most commonly used medicinal and herbaceous traditional Chinese medicines that are currently considered for the treatment of diabetes mellitus and its complications. The alkaloids, flavonoids, and polysaccharides in mulberry leaves impart regulatory effects on blood sugar levels. To identify the hypoglycemia-related active components in mulberry leaves and their targets, the present study conducted gas chromatography-mass spectrometer (GC/MS), which identified 202 components of mulberry leaf, of which 22 components may have significant curative effects on diabetes mellitus and its complications and chronic inflammation...
May 18, 2018: European Journal of Pharmacology
https://www.readbyqxmd.com/read/29781307/anti-pseudomonas-aeruginosa-activity-of-hemlock-conium-maculatum-apiaceae-essential-oil
#6
Michela Di Napoli, Mario Varcamonti, Adriana Basile, Maurizio Bruno, Filippo Maggi, Anna Zanfardino
Conium maculatum is a nitrophilous weed belonging to the Apiaceae family and occurring in hedgerows, pastures, waste ground, along rivers and roadsides. Little is known on the chemistry and bioactivity of other secondary metabolites occurring in the plant. In the present work, we have analysed the chemical composition and antimicrobial activity of the essential oils hydrodistilled from leaves and inflorescenes of C. maculatum growing in Sicily, Italy. The composition of essential oils was achieved by gas chromatography-mass spectrometry (GC-MS) analysis, whereas the inhibitory effects on the growth of two Gram negative strains, namely Escherichia coli and Pseudomonas aeruginosa were assessed by two different analysis...
May 21, 2018: Natural Product Research
https://www.readbyqxmd.com/read/29781303/lavandula-x-intermedia-and-lavandula-angustifolia-essential-oils-phytochemical-composition-and-antimicrobial-activity-against-foodborne-pathogens
#7
Roberta Tardugno, Annalisa Serio, Federica Pellati, Serena D'Amato, Clemencia Chaves López, Maria Grazia Bellardi, Maura Di Vito, Vincenzo Savini, Antonello Paparella, Stefania Benvenuti
Four cultivars (cv) of Lavandula x intermedia ('Abrialis', 'Alba', 'Rinaldi Ceroni' (R.C.) and 'Sumiens') were cultivated in Italy and their essential oils (EOs) were distilled from Alfalfa Mosaic Virus-free plants. These EOs and one from L. angustifolia Miller were chemically characterised by GC-MS and GC-FID. Antimicrobial activity was evaluated against Listeria monocytogenes (24 strains) and Salmonella enterica (10 food strains). Minimal inhibitory concentrations (MIC) ≥ 10.0 μL/mL inhibited Salmonella (cv 'R...
May 21, 2018: Natural Product Research
https://www.readbyqxmd.com/read/29781296/variation-in-essential-oil-composition-of-teucrium-hircanicum-l-from-iran-a-rich-source-of-e-%C3%AE-bergamotene
#8
Mohammad Ali Rahimi, Vahideh Nazeri, Seyed Ali Andi, Fatemeh Sefidkon
In present work, the chemical composition of the essential oils obtained from dried flowering aerial parts of Teucrium hircanicum L. (Labiatae) originated from ten wild populations in Iran was analyzed by a GC-FID and GC/MS system. The oil yields varied from 0.04% to 0.1%. A total of thirty-two compounds representing 67.6-97.7% of the oil were identified. The essential oil was found to be rich in sesquiterpene hydrocarpons (E)-α-bergamotene (17.5-86.9%) and (E)-β-farnesene (0.5-21.4%). Of the total identified compounds, sesquiterpene hydrocarpons (36...
May 21, 2018: Natural Product Research
https://www.readbyqxmd.com/read/29779663/identification-of-enzymes-involved-in-sesterterpene-biosynthesis-in-marine-fungi
#9
Jingjing Yan, Jingjing Guo, Wei Yuan, Wanying Mai, Kui Hong
Diverse and bioactive terpene compounds are produced by marine fungi. The biosynthesis of sesterterpene molecules containing a C25 skeleton is catalyzed by chimeric enzymes that carry out both chain elongation and terpene cyclization reactions. These bifunctional characteristics facilitate using different chain length polyisoprenoid diphosphates as precursors to yield the geranylfarnesyl diphosphate intermediate, which is then converted to a sesterterpene in one step. In this chapter, we describe the identification of sesterterpene synthase enzymes, together with other related enzymes such as diterpene and farnesyl diphosphate synthases, in a single fungal strain...
2018: Methods in Enzymology
https://www.readbyqxmd.com/read/29779131/production-and-characterization-of-exopolysaccharides-by-geobacillus-thermodenitrificans-arza-6-and-geobacillus-toebii-arza-8-strains-isolated-from-an-armenian-geothermal-spring
#10
Hovik Panosyan, Paola Di Donato, Annarita Poli, Barbara Nicolaus
The thermal ecosystems, including geothermal springs, are proving to be source of thermophiles able to produce extracellular polysaccharides (EPSs). Among the sixteen thermophilic bacilli isolated from sediment sampled from Arzakan geothermal spring, Armenia, two best EPSs producer strains were identified based on 16S rRNA gene sequence analysis and phenotypic characteristics, and designated as Geobacillus thermodenitrificans ArzA-6 and Geobacillus toebii ArzA-8 strains. EPSs production was investigated under different time, temperature and culture media's composition...
May 19, 2018: Extremophiles: Life Under Extreme Conditions
https://www.readbyqxmd.com/read/29778878/structural-elucidation-of-lignin-carbohydrate-complexes-lccs-from-chinese-quince-chaenomeles-sinensis-fruit
#11
Zhao Qin, Yu-Xiang Ma, Hua-Min Liu, Guang-Yong Qin, Xue-De Wang
The lignin-carbohydrate complexes (LCC) of the mesocarp (MS) and near the endocarp (NE) of Chinese quince (Chaenomeles sinensis) fruits were analyzed using three different methods of fractioning: milled wood lignin (MWL), LCC extracted from crude MWL with acetic acid (LCC-AcOH), and Bjorkman LCC. The MWL and LCC fractions were characterized by carbohydrate composition analysis, SEC, FT-IR, Py-GC/MS, thermal analysis and 2D HSQC NMR. Notably, large amounts of arabinose and galactose remained in the Björkman LCC fractions suggesting a chemical bond between the lignin and pectin...
May 17, 2018: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/29778820/synthesis-of-bioactive-compounds-from-vermicast-isolated-actinomycetes-species-and-its-antimicrobial-activity-against-human-pathogenic-bacteria
#12
R Balachandar, N Karmegam, M Saravanan, R Subbaiya, P Gurumoorthy
The present study aimed to evaluate the antimicrobial activities of bioactive compounds synthesized from vermicast isolated actinomycetes species. Specifically, the synthesized bioactive compounds were evaluated for their antimicrobial activity against selected Gram + ve and Gram-ve human pathogenic bacteria including Staphylococcus aureus, Bacillus circulans, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli. Interestingly, a total of five different actinomycetesspecies were recovered from vermicasts...
May 17, 2018: Microbial Pathogenesis
https://www.readbyqxmd.com/read/29778814/environmental-and-lifestyle-factors-affecting-exposure-to-polycyclic-aromatic-hydrocarbons-in-the-general-population-in-a-middle-eastern-area
#13
Mohammad Hoseini, Ramin Nabizadeh, Juana Maria Delgado-Saborit, Ata Rafiee, Kamyar Yaghmaeian, Saeid Parmy, Sasan Faridi, Mohammad Sadegh Hassanvand, Masud Yunesian, Kazem Naddafi
The aim of this study was to investigate environmental and lifestyle factors affecting exposure to PAHs in the general population in a large city of the Middle East (Tehran) by measuring urinary monohydroxy polycyclic aromatic hydrocarbons (OH-PAHs) and establishing relationships between PAHs exposure and related factors. Urine samples were collected from 222 randomly chosen subjects who were living in the urban area of Tehran, Iran. Subjects were required to complete a detailed questionnaire aimed to document their personal and sociodemographic information, activities, cooking-related appliances, smoking history/exposure, and consumed foodstuff...
May 17, 2018: Environmental Pollution
https://www.readbyqxmd.com/read/29778796/effect-of-operating-conditions-on-hydrothermal-liquefaction-of-spirulina-over-ni-tio-2-catalyst
#14
Wenying Tian, Renlong Liu, Wenjia Wang, Zhaosen Yin, Xuewen Yi
In this study, the effects of reaction temperature, holding time, algae/water ratio and catalyst dosage on the yield and quality of bio-oil produced via the HTL of Spirulina were investigated. The maximum bio-oil yield (43.05 wt%) and energy recovery (ER) value (64.62%) were obtained at 260 °C for 30 min, with an algae/water ratio of 1/4 and a catalyst dosage of 5 wt%. The bio-oil samples were characterized by elemental analysis, Gas Chromatography-Mass Spectrometry (GC-MS), Fourier Transform Infrared (FI-IR), and Thermo-gravimetric analysis (TGA)...
May 4, 2018: Bioresource Technology
https://www.readbyqxmd.com/read/29778466/in-vitro-susceptibility-of-trypanosoma-brucei-brucei-to-selected-essential-oils-and-their-major-components
#15
Sonya Costa, Cláudia Cavadas, Carlos Cavaleiro, Lígia Salgueiro, Maria do Céu Sousa
Aiming for discovering effective and harmless antitrypanosomal agents, 17 essential oils and nine major components were screened for their effects on T. b. brucei. The essential oils were obtained by hydrodistillation from fresh plant material and analyzed by GC and GC-MS. The trypanocidal activity was assessed using blood stream trypomastigotes cultures of T. b. brucei and the colorimetric resazurin method. The MTT test was used to assess the cytotoxicity of essential oils on macrophage cells and Selectivity Indexes were calculated...
May 17, 2018: Experimental Parasitology
https://www.readbyqxmd.com/read/29778164/monitoring-of-943-organic-micropollutants-in-wastewater-from-municipal-wastewater-treatment-plants-with-secondary-and-advanced-treatment-processes
#16
Juan Wang, Zhe Tian, Yingbin Huo, Min Yang, Xingcan Zheng, Yu Zhang
To perform a systematic survey on the occurrence and removal of micropollutants during municipal wastewater treatment, 943 semi-volatile organic chemicals in 32 wastewater samples including influents of secondary treatments, secondary effluents and final effluents (effluents of advanced treatments), which were collected from seven full-scale municipal wastewater treatment plants (MWTPs) in China, were examined by gas chromatography-mass spectrometry (GC-MS) coupled with an automated identification and quantification system with a database (AIQS-DB)...
May 2018: Journal of Environmental Sciences (China)
https://www.readbyqxmd.com/read/29778008/plasma-metabolic-changes-in-chinese-hiv-infected-patients-receiving-lopinavir-ritonavir-based-treatment-implications-for-hiv-precision-therapy
#17
Xiaolin Li, Tong Wu, Yongjun Jiang, Zining Zhang, Xiaoxu Han, Wenqing Geng, Haibo Ding, Jing Kang, Qi Wang, Hong Shang
OBJECTIVES: The goal of this study is to profile the metabolic changes in the plasma of HIV patients receiving lopinavir/ritonavir (LPV/r)-based highly active antiretroviral therapy (HAART) relative to their treatment-naïve phase, aimed to identify precision therapy for HIV for improving prognosis and predicting dyslipidemia caused by LPV/r. METHODS: 38 longitudinal plasma samples were collected from 19 HIV-infected patients both before and after antiretroviral therapy, and 18 samples from healthy individuals were used as controls...
May 16, 2018: Cytokine
https://www.readbyqxmd.com/read/29777680/assay-for-abscisic-acid-8-hydroxylase-activity-of-cloned-plant-cytochrome-p450-oxidases-in-saccharomyces-cerevisiae
#18
Stella Eggels, Viktoriya Avramova, Chris-Carolin Schön, Brigitte Poppenberger, Wilfried Rozhon
The plant hormone abscisic acid (ABA) regulates many processes, including response to drought, seed dormancy and abscission of leaves and fruits. For maintenance of ABA homeostasis, catabolism of ABA by 8'-hydroxylation and subsequent cyclisation to phaseic acid (PA) is crucial. However, detection of ABA 8'-hydroxylation activity is tedious. We present a simple and rapid method for detection of ABA 8'-hydroxylase activity by cloning cDNAs of interest and expressing the respective protein in yeast. Upon addition of ABA, PA is formed and subsequently quantified in the yeast cell culture supernatant by heart cutting 2D-HPLC or GC-MS...
May 16, 2018: Analytical Biochemistry
https://www.readbyqxmd.com/read/29777442/study-on-immobilization-of-marine-oil-degrading-bacteria-by-carrier-of-algae-materials
#19
Yiran Zhang, Wei Gao, Faxiang Lin, Bin Han, Changfei He, Qian Li, Xiangxing Gao, Zhisong Cui, Chengjun Sun, Li Zheng
This study investigated the immobilizations with of bacteria two kinds of algal materials, Enteromorpha residue and kelp residue. The lipophilicity of them were compared by diesel absorption rates. The immobilization efficiency of Bacillus sp. E3 was measured to evaluate whether these carriers would satisfy the requirement for biodegradation of oil spills. The bacteria were immobilized through adsorption with the sterilized and non-sterilized carriers to compare the differences between the two treatments. Oil degradation rates were determined using gravimetric and GC-MS methods...
May 18, 2018: World Journal of Microbiology & Biotechnology
https://www.readbyqxmd.com/read/29777312/evaluating-organochlorine-pesticide-residues-in-the-aquatic-environment-of-the-lake-naivasha-river-basin-using-passive-sampling-techniques
#20
Yasser Abbasi, Chris M Mannaerts
Passive sampling techniques can improve the discovery of low concentrations by continuous collecting the contaminants, which usually go undetected with classic and once-off time-point grab sampling. The aim of this study was to evaluate organochlorine pesticide (OCP) residues in the aquatic environment of the Lake Naivasha river basin (Kenya) using passive sampling techniques. Silicone rubber sheet and Speedisk samplers were used to detect residues of α-HCH, β-HCH, γ-HCH, δ-HCH, heptachlor, aldrin, heptachlor epoxide, pp-DDE, endrin, dieldrin, α-endosulfan, β-endosulfan, pp-DDD, endrin aldehyde, pp-DDT, endosulfan sulfate, and methoxychlor in the Malewa River and Lake Naivasha...
May 18, 2018: Environmental Monitoring and Assessment
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