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https://www.readbyqxmd.com/read/28538661/mass-spectrometry-based-profiling-and-imaging-of-various-ginsenosides-from-panax-ginseng-roots-at-different-ages
#1
Jae Won Lee, Seung-Heon Ji, Young-Seob Lee, Doo Jin Choi, Bo-Ram Choi, Geum-Soog Kim, Nam-In Baek, Dae Young Lee
(1) Background: Panax ginseng root is one of the most important herbal products, and the profiling of ginsenosides is critical for the quality control of ginseng roots at different ages in the herbal markets. Furthermore, interest in assessing the contents as well as the localization of biological compounds has been growing. The objective of this study is to carry out the mass spectrometry (MS)-based profiling and imaging of ginsenosides to assess ginseng roots at different ages; (2) Methods: Optimal ultra performance liquid chromatography coupled to quadrupole time of flight/MS (UPLC-QTOF/MS) was used to profile various ginsenosides from P...
May 24, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28538205/a-rapid-microextraction-by-packed-sorbent-liquid-chromatography-tandem-mass-spectrometry-method-for-the-determination-of-dexamethasone-disodium-phosphate-and-dexamethasone-in-aqueous-humor-of-patients-with-uveitis
#2
Federica Bianchi, Monica Mattarozzi, Nicolò Riboni, Paolo Mora, Stefano A Gandolfi, Maria Careri
A new method based on microextraction by packed sorbent (MEPS) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and validated for the determination of dexamethasone and dexamethasone disodium phosphate in human aqueous humor. A central composite design was applied to investigate the effects of both loading and eluting cycles in the MEPS procedure; subsequently the multicriteria method of the desirability functions allowed to find the best conditions for the simultaneous extraction of both the analytes...
May 15, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28535591/effect-of-water-stage-and-tree-stand-composition-on-spatiotemporal-differentiation-of-spring-water-chemistry-draining-carpathian-flysch-slopes-gorce-mts
#3
Michał Jasik, Stanisław Małek, Mirosław Żelazny
The purpose of this study was to identify the factors affecting spring water chemistry in different tree stands and to measure the influence of water stage on the physicochemical parameters of spring waters in a small Carpathian catchment. Water samples were collected three times per year at various stages of the water: after the spring thaw, after a period of heavy rain and after a dry period in 2011 and 2012. Water samples were left in the laboratory to reach room temperature (19-20°C) and analyzed for EC (reference T=25°C) and pH...
May 19, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28533032/design-and-synthesis-of-an-immobilized-metal-affinity-chromatography-and-metal-oxide-affinity-chromatography-hybrid-material-for-improved-phosphopeptide-enrichment
#4
Da-Song Yang, Xi-Ying Ding, Hong-Ping Min, Bo Li, Meng-Xiang Su, Miao-Miao Niu, Bin Di, Fang Yan
Reversible phosphorylation of proteins is one of the most important post-translational modifications, while the detection of phosphopeptides is difficult due to their low abundance and the signal suppression of nonphosphorylated peptides. Therefore, selective enrichment of phosphopeptides from highly complicated mixtures is vital for MS-based phosphoproteome analysis. Despite various strategies have been developed, there is no single method that is capable of providing full coverage of the whole phosphoproteome...
May 10, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28532227/peptides-extracted-from-edible-mushroom-lentinus-squarrosulus-induces-apoptosis-in-human-lung-cancer-cells
#5
Arisara Prateep, Somruethai Sumkhemthong, Maneewan Suksomtip, Pithi Chanvorachote, Chatchai Chaotham
CONTEXT: Lentinus squarrosulus Mont. (Polyporaceae) is an interesting source of diverse bioactive compounds. OBJECTIVE: This is the first study of the anticancer activity and underlying mechanism of peptides extracted from Lentinus squarrosuls. MATERIALS AND METHODS: Peptides were isolated from the aqueous extract of L. squarrosulus by employing solid ammonium sulphate precipitation. They were further purified by ion-exchange chromatography on diethylaminoethanol (DEAE)-cellulose and gel filtration chromatography on Sephadex G25...
December 2017: Pharmaceutical Biology
https://www.readbyqxmd.com/read/28531844/development-of-an-uplc-ms-ms-method-for-simultaneous-quantitation-of-11-d-amino-acids-in-different-regions-of-rat-brain-application-to-a-study-on-the-associations-of-d-amino-acid-concentration-changes-and-alzheimer-s-disease
#6
Zhe Li, Yuping Xing, Xingjie Guo, Yan Cui
There are significant differences in d-amino acid concentrations between healthy people and Alzheimer's disease patients. In order to investigate the potential correlation between d-amino acids and Alzheimer's disease, a simple and sensitive ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method has been developed. The method was applied to simultaneous determination of 11 d-amino acids in different regions of rat brain. Rat brain homogenates were firstly pretreated with protein precipitation procedure and then derivatized with (S)-N-(4-nitrophenoxycarbonyl) phenylalanine methoxyethyl ester [(S)-NIFE]...
May 11, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28531843/rapid-ic-ms-ms-determination-of-methylphosphonic-acid-in-urine-of-rats-exposed-to-organophosphorus-nerve-agents
#7
Timur Baygildiev, Alexandra Zatirakha, Igor Rodin, Arkady Braun, Andrey Stavrianidi, Nadezhda Koryagina, Igor Rybalchenko, Oleg Shpigun
A direct approach for the determination of a specific hydrolysis product of organophosphorus nerve agents such as methylphosphonic acid (MPA) in urine by ion chromatography and tandem mass spectrometry (IC-MS/MS) has been developed. The first advantage of the proposed approach is a rapid and simple sample preparation, which does not require a large sample volume, complicated and laborious preconcentration and derivatization steps, and takes less than 7min per sample. The second advantage is the fast and selective IC determination of MPA carried out on a noncommercial anion exchanger based on a poly(styrene-co-divinylbenzene) (PS-DVB) substrate with a high degree of crosslinking and a covalently-bonded branched functional layer, which enables complete resolution of MPA from major urine matrix components and allows one to overcome matrix effects...
May 8, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28531457/new-structural-insights-into-the-oligosaccharide-phosphate-fraction-of-pichia-hansenula-holstii-nrrl-y2448-phosphomannan
#8
Paul N Handley, Anthony Carroll, Vito Ferro
The oligosaccharide phosphate fraction (OPF) obtained from mild acid hydrolysis of P. holstii NRRL Y-2448 phosphomannan is the starting material for the preparation of the Phase III anticancer drug candidate PI-88. The OPF was for the first time successfully separated by preparative ion exchange chromatography and the major oligosaccharides isolated and characterized by NMR spectroscopy. The components were also acetylated and subjected to LC-MS analysis. These studies revealed that the OPF also contained all-α(1 → 3)-linked oligosaccharides in addition to the known α(1 → 3)/(1 → 2)-linked species, most likely formed by hydrolysis of the latter...
May 13, 2017: Carbohydrate Research
https://www.readbyqxmd.com/read/28529698/seven-perspectives-on-gpcr-h-d-exchange-proteomics-methods
#9
Xi Zhang
Recent research shows surging interest to visualize human G protein-coupled receptor (GPCR) dynamic structures using the bottom-up H/D-exchange (HDX) proteomics technology. This opinion article clarifies critical technical nuances and logical thinking behind the GPCR HDX proteomics method, to help scientists overcome cross-discipline pitfalls, and understand and reproduce the protocol at high quality. The 2010 89% HDX structural coverage of GPCR was achieved with both structural and analytical rigor. This article emphasizes systematically considering membrane protein structure stability and compatibility with chromatography and mass spectrometry (MS) throughout the pipeline, including the effects of metal ions, zero-detergent shock, and freeze-thaws on HDX result rigor...
2017: F1000Research
https://www.readbyqxmd.com/read/28528542/performance-of-a-high-pressure-liquid-chromatography-ion-mobility-mass-spectrometry-system-for-metabolic-profiling
#10
Xing Zhang, Kimberly Kew, Richard Reisdorph, Mark Sartain, Roger Powell, Michael L Armstrong, Kevin Quinn, Charmion Cruickshank-Quinn, Scott Walmsley, Samantha S Bokatzian, Ed Darland, Matthew Rain, Kenneth Imatani, Nichole Reisdorph
A commercial liquid chromatography/drift tube ion mobility-mass spectrometer (LC/IM-MS) was evaluated for its utility in global metabolomics analysis. Performance was assessed using twelve targeted metabolite standards where the limit of detection (LOD), linear dynamic range, resolving power, and collision cross section (Ω), is reported for each standard. Data was collected in three different instrument operation modes: flow injection analysis with IM-MS (FIA/IM-MS), LC/MS and LC/IM-MS. Metabolomics analyses of human plasma and HaCaT cells were used to compare the above three operation modes...
May 22, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28528228/determination-of-soluble-sugar-profile-in-rice
#11
Xianqiao Hu, Changyun Fang, Lin Lu, Zhanqiang Hu, Yafang Shao, Zhiwei Zhu
Soluble sugars in rice are the main components affecting sweetness taste of rice. In this paper, an accurate, precise and rapid method for simultaneous determination of multi soluble sugars in rice by using ion chromatography equipped with pulsed amperometric detector was presented. Pretreatment and parameters of ion chromatography and pulsed amperometric detector were optimized. Regression coefficients (R) of 0.9998, 1.0000, 0.9979, 0.9998 and 0.9998 were obtained for glucose, fructose, sucrose, raffinose and maltose, respectively...
May 5, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28527994/purification-and-characterization-of-a-protease-resistant-phytase-of-aspergillus-oryzae-sbs50-whose-properties-make-it-exceptionally-useful-as-a-feed-supplement
#12
Sapna, Bijender Singh
An extracellular phytase of Aspergillus oryzae SBS50 was purified to homogeneity using ammonium sulphate precipitation, ion-exchange and gel filtration chromatography. Purified phytase has a monomeric molecular mass of ∼80kDa exhibiting its optimal activity at pH 5.0 and 50°C with a T 1/2 of 300min at 50°C. Phytase of A. oryzae displayed broad substrate specificity with Vmax and Km values of 58.82μmol/ml/min and 1.14mM, respectively, for calcium phytate. Purity and homogeneity of the phytase was confirmed by high performance liquid chromatography and MALDI-TOF analysis revealed the identification of a peptide showing homology with acid phosphatase of Aspergillus oryzae RIB40...
May 17, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28527288/-partial-purification-of-peptides-present-in-the-tityus-macrochirus-buthidae-scorpion-venom-and-preliminary-assessment-of-their-cytotoxicity
#13
Clara Andrea Rincón-Cortés, Edgar Antonio Reyes-Montaño, Nohora Angélica Vega-Castro
INTRODUCTION: Scorpion venom contains peptides with neurotoxic action primarily active on ion channels in the nervous system of insects and mammals. They are also characterized as cytolytic and anticancer, biological characteristics that have not yet been reported for the Tityus macrochirus venom. OBJECTIVE: To assess if the total T. macrochirus venom and the fraction of partially purified peptides decrease the viability of various tumor-derived cell lines. MATERIALS AND METHODS: The scorpion venom was collected by electrical stimulation and, subsequently, subjected to chromatography, electrophoresis, and ultrafiltration with Amicon Ultra 0...
June 1, 2017: Biomédica: Revista del Instituto Nacional de Salud
https://www.readbyqxmd.com/read/28527001/the-relative-abundance-of-dimethylsulfoniopropionate-dmsp-among-other-zwitterions-in-branching-coral-at-heron-island-southern-great-barrier-reef
#14
Hilton B Swan, Elisabeth S M Deschaseaux, Graham B Jones, Bradley D Eyre
Dimethylsulfoniopropionate (DMSP) and eleven other target zwitterions were quantified in the branch tips of six Acropora species and Stylophora pistillata hard coral growing on the reef flat surrounding Heron Island in the southern Great Barrier Reef (GBR), Australia. Hydrophilic interaction liquid chromatography mass spectrometry (HILIC-MS) was used for sample analysis with isotope dilution MS applied to quantify DMSP. The concentration of DMSP was ten times greater in A. aspera than A. valida, with this difference being maintained throughout the spring, summer and winter seasons...
May 20, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28524783/quantitative-analysis-of-veterinary-drugs-in-bovine-muscle-and-milk-by-liquid-chromatography-quadrupole-time-of-flight-mass-spectrometry
#15
Shizuka Saito-Shida, Takatoshi Sakai, Satoru Nemoto, Hiroshi Akiyama
A simple and reliable multiresidue method for quantitative determination of veterinary drugs in bovine muscle and milk using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) was developed. Critical MS parameters such as capillary voltage, cone voltage, collision energy, desolvation gas temperature, and extraction mass window were carefully optimised to obtain the best possible sensitivity. Analytical samples were prepared using extraction with acetonitrile and hexane in the presence of anhydrous sodium sulphate and acetic acid, followed by ODS cartridge clean-up...
May 19, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28524200/isolation-of-a-novel-bioactive-protein-from-an-edible-mushroom-pleurotus-eryngii-and-its-anti-inflammatory-potential
#16
Biao Yuan, Liyan Zhao, Kanyasiri Rakariyatham, Yanhui Han, Zili Gao, Benard Muinde Kimatu, Qiuhui Hu, Hang Xiao
Edible mushrooms are rich sources of bioactive components. In this study, a bioactive protein, PEP, was isolated from an edible mushroom, Pleurotus eryngii, through (NH4)2SO4 precipitation and ion-exchange chromatography. Proteomic analysis by matrix assisted laser desorption ionization-time of flight mass spectrometry showed that PEP was a novel protein with a molecular weight of 40 kDa. PEP exhibited anti-inflammatory effects in LPS-stimulated RAW 264.7 macrophages by inhibiting the overproduction of pro-inflammatory mediators including nitric oxide (NO), cytokine IL-1β and IL-6...
May 19, 2017: Food & Function
https://www.readbyqxmd.com/read/28522166/development-and-validation-of-a-simplified-titration-method-for-monitoring-volatile-fatty-acids-in-anaerobic-digestion
#17
Hao Sun, Jianbin Guo, Shubiao Wu, Fang Liu, Renjie Dong
The volatile fatty acids (VFAs) concentration has been considered as one of the most sensitive process performance indicators in anaerobic digestion (AD) process. However, the accurate determination of VFAs concentration in AD processes normally requires advanced equipment and complex pretreatment procedures. A simplified method with fewer sample pretreatment procedures and improved accuracy is greatly needed, particularly for on-site application. This report outlines improvements to the Nordmann method, one of the most popular titrations used for VFA monitoring...
May 15, 2017: Waste Management
https://www.readbyqxmd.com/read/28521953/optimized-selection-of-liquid-chromatography-conditions-for-wide-range-analysis-of-natural-compounds
#18
Aurélie Periat, Davy Guillarme, Jean-Luc Veuthey, Julien Boccard, Sofia Moco, Denis Barron, Alexandre Grand-Guillaume Perrenoud
Plant secondary metabolites are an almost unlimited reservoir of potential bioactive compounds. In view of the wide chemical space covered by natural compounds, their comprehensive analysis requires multiple and complementary approaches. In this study, numerous chromatographic conditions were tested for the analysis of a set of 120 representative natural compounds covering a wide polarity range (18 log P units). The experiments were performed on 59 different conditions involving 29 RPLC and HILIC dedicated stationary phases, as well as more exotic mixed mode columns...
May 10, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28521276/an-atmospheric-pressure-ionization-source-using-a-high-voltage-target-compared-to-electrospray-ionization-for-the-lc-ms-analysis-of-pharmaceutical-compounds
#19
Arnaud Lubin, Ronald De Vries, Deirdre Cabooter, Patrick Augustijns, Filip Cuyckens
The type and design of an ionization source can have a significant influence on the performances of a bioanalytical method. It is, therefore, of high interest to evaluate the performances of newly introduced sources to highlight their benefits and limitations in comparison to other well established sources. In this paper, liquid chromatography - mass spectrometry (LC/MS) performances of a new atmospheric pressure ionization (API) source, commercialized as UniSpray, is evaluated. The dynamic range of 24 pharmaceutical and biological compounds is compared between the new API source and electrospray ionization (ESI) for 3 different mobile phase conditions...
May 4, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28521273/rapid-discovery-of-cyclopamine-analogs-from-fritillaria-and-veratrum-plants-using-lc-q-tof-ms-and-lc-qqq-ms
#20
Yuan Du, Zu-Guo Zheng, Yue Yu, Zi-Tian Wu, Dan Liang, Ping Li, Yan Jiang, Hui-Jun Li
Cyclopamine, an inhibitor of the Hedgehog (Hh) signaling pathway, has been paid much attention in treating a wide variety of tumors. However, isolation and purification of cyclopamine analogs from medicinal plants remain challengeable. We herein proposed an efficient strategy using liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-Q-TOF-MS) and liquid chromatography triple-quadrupole mass spectrometry (LC-QqQ-MS) for rapid screening and targeted isolation of cyclopamine analogs in Fritillaria and Veratrum plants...
May 1, 2017: Journal of Pharmaceutical and Biomedical Analysis
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