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https://www.readbyqxmd.com/read/28535423/chromatographic-separation-and-detection-methods-of-aloe-arborescens-miller-constituents-a-systematic-review
#1
REVIEW
Jilan A Nazeam, Haidy A Gad, Hala M El-Hefnawy, Abdel-Naser B Singab
Aloe arborescens Miller (Family Asphodelaceae) is a member of genus Aloe, which is used in traditional medicine to cure various diseases. The extracts of the plant have been reported to possess anticancer, immunomodulator, antidiabetic, anti-inflammatory and antioxidant activities. The phytochemical investigations have revealed diverse chemical constituents, including phenolics [anthraquinones, anthrones, pyrones, chromones and coumarins], polysaccharides [arborans [(1-4) linked glucomannans, polysaccharide (A, B and C): (A: a linear (1-6)-O-α-glucan, B: a branching (1-2)-O-l-arabinose with (1-2)-O-d-galactose linkages and C: (1-4)-O-β-mannan with 18% acetyl group)]], glycoproteins and carboxypeptidase enzyme...
April 29, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28533028/optimizing-targeted-untargeted-metabolomics-by-automating-gas-chromatography-mass-spectrometry-gc-gc-ms-and-gc-ms-workflows
#2
Albert Robbat, Nicole Kfoury, Eugene Baydakov, Yuriy Gankin
New database building and MS subtraction algorithms have been developed for automated, sequential two-dimensional gas chromatography/mass spectrometry (GC-GC/MS). This paper reports the first use of a database building tool, with full mass spectrum subtraction, that does not rely on high resolution MS data. The software was used to automatically inspect GC-GC/MS data of high elevation tea from Yunnan, China, to build a database of 350 target compounds. The database was then used with spectral deconvolution to identify 285 compounds by GC/MS of the same tea...
May 8, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28531831/workflow-methodology-for-rat-brain-metabolome-exploration-using-nmr-lc-ms-and-gc-ms-analytical-platforms
#3
Binta Diémé, Antoine Lefèvre, Lydie Nadal-Desbarats, Laurent Galineau, Blandine Madji Hounoum, Frédéric Montigny, Hélène Blasco, Christian R Andres, Patrick Emond, Sylvie Mavel
We developed a multi-platform approach for the metabolome exploration of rat brain tissue, using liquid chromatography coupled with mass spectrometry (LC-MS), nuclear magnetic resonance spectroscopy (NMR) and gas-chromatography coupled with mass spectrometry (GC-MS). The critical steps for metabolite exploration of cerebral tissues are tissue lysis and metabolites extraction. We first evaluated the impact of freeze-drying compared to wet tissue metabolites extraction using NMR and LC-MS with a reversed phase liquid chromatography...
May 13, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28531658/co-plantation-of-aquatic-macrophytes-typha-angustifolia-and-paspalum-scrobiculatum-for-effective-treatment-of-textile-industry-effluent
#4
Vishal V Chandanshive, Niraj R Rane, Asif S Tamboli, Avinash R Gholave, Rahul V Khandare, Sanjay P Govindwar
Field treatment of textile industry effluent was carried out in constructed drenches (91.4m×1.2m×0.6m; 65.8m(3)) planted independently with Typha angustifolia, Paspalum scrobiculatum and their co-plantation (consortium-TP). The in situ treatment of effluent by T. angustifolia, P. scrobiculatum and consortium-TP was found to decrease ADMI color value by 62, 59 and 76%, COD by 65, 63 and 70%, BOD by 68, 63 and 75%, TDS by 45, 39 and 57%, and TSS by 35, 31 and 47%, respectively within 96h. Heavy metals such as arsenic, cadmium, chromium and lead were also removed up to 28-77% after phytoremediation...
May 12, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28527388/abiotic-transformation-of-hexabromocyclododecane-by-sulfidated-nanoscale-zerovalent-iron-kinetics-mechanism-and-influencing-factors
#5
Dan Li, Xifen Zhu, Yin Zhong, Weilin Huang, Ping'an Peng
Recent studies showed that sulfidated nanoscale zerovalent iron (S-nZVI) is a better reducing agent than nanoscale zerovalen iron (nZVI) alone for reductive dechlorination of several organic solvents such as trichloroethylene (TCE) due to the catalytic role of iron sulfide (FeS). We measured the rates of transformation of hexabromocyclododecane (HBCD) by S-nZVI and compared them to those by FeS, nZVI, and reduced sulfur species. The results showed that: i) HBCD (20 mg L(-1)) was almost completely transformed by S-nZVI (0...
May 9, 2017: Water Research
https://www.readbyqxmd.com/read/28527332/determination-of-parabens-in-human-urine-by-optimal-ultrasound-assisted-emulsification-microextraction-and-on-line-acetylation-gas-chromatography-mass-spectrometry
#6
Zhou Hui-Ting, Erica M C Ding, Wang-Hsien Ding
An effective and solvent-less method for the rapid determination of four commonly detected parabens (methyl-, ethyl-, propyl- and butyl-) in human urine samples is described. This method employed ultrasound-assisted emulsification microextraction (USAEME) before identification and quantitation of the parabens via on-line acetylation gas chromatography-mass spectrometry (GC-MS). Urine samples were enzymatically de-conjugated with β-glucuronidase and then extracted by an optimal USAEME procedure for the measurement of total concentrations of target analytes...
May 10, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28525815/an-integrated-approach-to-study-the-risk-from-landfill-soil-of-delhi-chemical-analyses-in-vitro-assays-and-human-risk-assessment
#7
Swati, Pooja Ghosh, Indu Shekhar Thakur
In the present study, landfill soil of three municipal solid waste landfill sites of Delhi, India were toxico-chemically analyzed for human risk assessment as inadequate information is available on the possible health effects of the contaminants present in landfill soil. The landfill soil samples were prepared for analyzing heavy metal concentration, organic contaminants and toxicity analysis separately. Composite soil sample collected from three landfill sites were analyzed for heavy metal by ICP-AES. Metal concentration so obtained was below the permissible limit of soil but higher than the set limits for effluent...
May 16, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28521980/sulphated-polysaccharide-isolated-from-sargassum-vulgare-characterization-and-hypolipidemic-effects
#8
Rihab Ben Abdallah Kolsi, Hichem Ben Salah, Neila Jardak, Rim Chaaben, Imed Jribi, Abdelfattah El Feki, Tarak Rebai, Kamel Jamoussi, Noureddine Allouche, Cristophe Blecker, Hafedh Belghith, Karima Belghith
A sulphated polysaccharide from brown algae Sargassum vulgare (SVSP) was extracted and examined with respect to chemical, structural characterization and hypolipidemic effects. SVSP consisted mainly of sulphate and total sugars with low levels of lipids and proteins. Its structure was studied by nuclear magnetic resonance (RMN), gas chromatography-mass spectrometry (GC-MS), infra-red spectroscopic, differential scanning calorimetry and X-ray diffraction analysis. Allowing us therefore to revealed that SVSP was composed of glucose, rhamnose, xylose, galactose, mannose and arabinose with XRD pattern that was typical for a semi-crystalline polymer and complexities of the spectra reflected its homogeneous structure...
August 15, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28521954/gas-chromatography-mass-spectrometry-strategies-for-the-accurate-and-sensitive-speciation-of-sulfur-dioxide-in-wine
#9
Vanesa Carrascon, Ignacio Ontañón, Mónica Bueno, Vicente Ferreira
Understanding the chemistry of wine oxidation requires the accurate and sensitive quantitative determination of the most important molecular species which SO2 can form. An analytical strategy based in three independent static headspace GC-MS determinations is proposed in order to obtain information about the total, nominally free and truly free levels of SO2. Nominally free forms are directly determined after sample acidulation, total forms require the previous incubation at 100°C, and truly free forms are determined after preconcentration of the headspace of the undisturbed sample in an alkaline solution...
May 8, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28521827/antioxidant-activity-acetylcholinesterase-inhibitory-potential-and-phytochemical-analysis-of-sarcocephalus-latifolius-sm-bark-used-in-traditional-medicine-in-sudan
#10
Alsiddig Osama, Sufyan Awadelkarim, Amna Ali
BACKGROUND: Sarcocephalus latifolius is used as a traditional medicine for curing many diseases in Sudan. The main objective of the current study was to determine the antioxidant activity and acetylcholinesterase inhibition (AChEI) of S. latifolius, and to estimate its total phenolic and flavonoid contents. METHODS: Antioxidant activity of the tested plant extracts was carried out by determining their ability to scavenge the 2,2-diphenyl-1-picryl hydrazyl (DPPH) free radical...
May 18, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28521275/development-and-validation-of-a-hs-gc-ms-method-for-the-simultaneous-analysis-of-diacetyl-and-acetylpropionyl-in-electronic-cigarette-refills
#11
Sophia Barhdadi, Michaël Canfyn, Patricia Courselle, Vera Rogiers, Tamara Vanhaecke, Eric Deconinck
The use of e-cigarettes as alternative for tobacco cigarettes has become increasingly popular, even though their safety has not yet been scientifically established. One of the frequently raised concerns is the potential toxicity of certain flavours present in the e-liquids, such as diacetyl and acetylpropionyl. It is therefore important to be able to identify and quantify both compounds. Numerous analytical methods have been published for determining e-liquid compositions, but concerns exist with respect to the lack of analytical evaluation...
May 4, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28520403/integrated-strategy-for-unknown-ei-ms-identification-using-quality-control-calibration-curve-multivariate-analysis-ei-ms-spectral-database-and-retention-index-prediction
#12
Teruko Matsuo, Hiroshi Tsugawa, Hiromi Miyagawa, Eiichiro Fukusaki
Compound identification using unknown electron ionization (EI) mass spectra in gas chromatography coupled with mass spectrometry (GC-MS) is challenging in untargeted metabolomics, natural product chemistry, or exposome research. While the total count of EI-MS records included in publicly or commercially available databases is over 900,000, efficient use of this huge database has not been achieved in metabolomics. Therefore, we proposed a 'four-step' strategy for the identification of biologically significant metabolites using an integrated cheminformatics approach: (i) Quality control calibration curve to reduce background noise, (ii) variable selection by hypothesis testing in principal component analysis for the efficient selection of target peaks, (iii) searching the EI-MS spectral database, and (iv) retention index (RI) filtering in combination with RI predictions...
May 18, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28516444/toxicological-analysis-of-opiates-from-alternative-matrices-collected-from-an-exhumed-body
#13
Marta Cippitelli, Dora Mirtella, Giovanni Ottaviani, Giovanna Tassoni, Rino Froldi, Mariano Cingolani
In this case study, the body of a 45-year-old man was exhumed after 1 year at the request of the public prosecutor to assess whether the death was caused by drug consumption. Toxicological analyses were performed on several matrices, including liver, kidney, and the alternative matrices hair and teeth. The systematic toxicological analysis (STA), which consisted of basic and acid liquid/liquid extraction and gas chromatography-mass spectrometry (GC-MS) analysis, showed the presence of opiates in each of the matrices analyzed...
May 18, 2017: Journal of Forensic Sciences
https://www.readbyqxmd.com/read/28516280/optimization-of-an-ultrasound-assisted-derivatization-for-gc-ms-analysis-of-oxygenated-organic-species-in-atmospheric-aerosol
#14
Maria Chiara Pietrogrande, Francesco Manarini, José Benito Quintana, Rosario Rodil, Eugenia Villaverde-de-Sáa, Marco Visentin
A novel ultrasound-assisted derivatization followed by GC/MS analysis was developed for the quantification of oxygenated organic species in ambient aerosol. Derivatization parameters mostly influencing the analytical response were investigated, i.e., solvent type, reagent concentration, and reaction duration. Response surface methodology was used to design experiments and a quadratic model was utilized to predict the variables and establish the optimal conditions. The study was performed on standard solutions of 30 compounds representing the major classes of oxygenated compounds typically found in ambient aerosol, i...
May 18, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28512469/metabolic-perturbation-and-potential-markers-in-patients-with-esophageal-cancer
#15
Xianlan Zhu, Kun Wang, Gaoshuang Liu, Yuqing Wang, Jin Xu, Linsheng Liu, Mengjie Li, Jian Shi, Jiye Aa, Lianzhen Yu
Clinical diagnosis of esophageal cancer (EC) at early stage is rather difficult. This study aimed to profile the molecules in serum and tissue and identify potential biomarkers in patients with EC. A total of 64 volunteers were recruited, and 83 samples (24 EC serum samples, 21 serum controls, 19 paired EC tissues, and corresponding tumor-adjacent tissues) were analyzed. The gas chromatography time-of-flight mass spectrometry (GC/TOF-MS) was employed, and principal component analysis was used to reveal the discriminatory metabolites and identify the candidate markers of EC...
2017: Gastroenterology Research and Practice
https://www.readbyqxmd.com/read/28512344/ecological-relevance-of-skeletal-fatty-acid-concentration-and-composition-in-mediterranean-scleractinian-corals
#16
Chiara Samorì, Erik Caroselli, Fiorella Prada, Michela Reggi, Simona Fermani, Zvy Dubinsky, Stefano Goffredo, Giuseppe Falini
The intra-skeletal fatty acid concentration and composition of four Mediterranean coral species, namely Cladocora caespitosa, Balanophyllia europaea, Astroides calycularis and Leptopsammia pruvoti, were examined in young and old individuals living in three different locations of the Mediterranean Sea. These species are characterized by diverse levels of organization (solitary or colonial) and trophic strategies (symbiotic or non-symbiotic). Fatty acids have manifold fundamental roles comprehensive of membrane structure fluidity, cell signaling and energy storage...
May 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28510485/metabolomic-response-to-huanglongbing-role-of-carboxylic-compounds-in-citrus-sinensis-response-to-candidatus-liberibacter-asiaticus-and-its-vector-diaphorina-citri
#17
Nabil Killiny, Yasser Nehela
Huanglongbing, a destructive disease of citrus, is caused by the fastidious bacterium, Candidatus Liberibacter asiaticus (CLas), and transmitted by Asian citrus psyllid, Diaphorina citri. The impact of CLas-infection and/or D. citri-infestation on Valencia sweet orange (Citrus sinensis) leaf metabolites was investigated using GC-MS, followed by gene expression analysis for 37 genes involved in jasmonic acid (JA), salicylic acid (SA), and proline-glutamine pathways. The total amino acid abundance increased after CLas-infection, while the total fatty acids increased dramatically after infestation with D...
May 16, 2017: Molecular Plant-microbe Interactions: MPMI
https://www.readbyqxmd.com/read/28510321/novel-zns-carbon-nanofibers-photocatalyst-for-degradation-of-rhodamine-6g-kinetics-tracking-of-operational-parameters-and-development-of-a-kinetics-model
#18
Ali Mehrizad, Parvin Gharbani
A novel nanocomposite in the role of photocatalyst was prepared by composition of zinc sulfide (ZnS) nanoparticles with carbon nanofibers (CNFs) and was characterized. The XRD, EDX, and FE-SEM analysis revealed that ZnS is successfully embedded in CNFs matrix. The DRS results indicated that supporting of ZnS by CNFs led to a decrease of the band gap energy. The photocatalytic degradation of a hazardous xanthine dye, Rhodamine 6 G (Rh-6G), by the prepared ZnS/CNFs composite was examined from the kinetics point of view...
May 16, 2017: Photochemistry and Photobiology
https://www.readbyqxmd.com/read/28508428/characterization-and-quantitation-of-pvp-content-in-a-silicone-hydrogel-contact-lens-produced-by-dual-phase-polymerization-processing
#19
Andrew J Hoteling, William F Nichols, Patricia S Harmon, Shawn M Conlon, Ivan M Nuñez, Joseph Hoff, Orlando M Cabarcos, Robert B Steffen, Daniel J Hook
Polyvinylpyrrolidone (PVP) has been incorporated over the years into numerous hydrogel contact lenses as both a primary matrix component and an internal wetting agent to increase lens wettability. In this study, complementary analytical techniques were used to characterize the PVP wetting agent component of senofilcon A and samfilcon A contact lenses, both in terms of chemical composition and amount present. Photo-differential scanning calorimetry (photo-DSC), gas chromatography with a flame ionization detector (GC-FID), and high-resolution/accurate mass (HR/AM) liquid chromatography-mass spectrometry (LC-MS) techniques confirmed dual phase reaction and curing of the samfilcon A silicone hydrogel material...
May 15, 2017: Journal of Biomedical Materials Research. Part B, Applied Biomaterials
https://www.readbyqxmd.com/read/28507944/a-survey-on-phytochemical-composition-and-biological-activity-of-zygophyllum-fabago-from-iran
#20
Saeid Yaripour, Mohammad-Reza Delnavazi, Parina Asgharian, Samira Valiyari, Saeed Tavakoli, Hossein Nazemiyeh
Purpose: Zygophyllum fabago L. (Z. fabago) is a widespread perennial herb which is used as a medicinal plant in traditional medicine of Iran, Turkey and China. The present study was a survey on phytochemical constituents and biological activities of this plant. Methods: Methanolic extract of the roots was fractionated over a C-18 pre-packed cartridge (Sep-pak) and chromatographic separation was performed on a reversed-phase preparative HPLC. Structural elucidation of the isolated compounds was carried out using UV, (1)H-NMR and 13C-NMR spectral analyses...
April 2017: Advanced Pharmaceutical Bulletin
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