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https://www.readbyqxmd.com/read/28231530/identification-of-a-novel-low-level-impurity-in-fungicide-pyraclostrobin-by-high-performance-liquid-chromatography-tandem-mass-spectrometry
#1
Kaimin Xia, ShanShan Shen, Qun Gao, Wei Shang, Yuanjiang Pan, Jun Wu
Pyraclostrobin is one kind of new type methoxy acrylate fungicides that has been widely used in agriculture at present, with a lot of advantages including broad spectrum, high efficiency and high selectivity. In this work, a novel low-level impurity in the pyraclostrobin at about 0.2% was separated and characterized by high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS). Firstly, the impurity was speculated to possess the same skeleton structure as the main product pyraclostrobin while the methyl group on the methyl ester was substituted to be CH2CH2Cl on the basis of the on-line multi-stage mass spectrometric behaviors compared with that of pyraclostrobin...
February 17, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28231529/new-enantioselective-lc-method-development-and-validation-for-the-assay-of-modafinil
#2
Marianna Harvanová, Taťána Gondová
For the first time, a new, fast and sensitive chromatographic method for the separation and determination of modafinil enantiomers was developed on chiral stationary phase with macrocyclic glycopeptide teicoplanin in the polar organic mode. The effect of the mobile phase composition and column temperature on the retention and enantioseparation were studied. The separation was performed using a Chirobiotic T column (250×4.6mm, 5μm) with methanol and triethylamine (100/0.05, v/v) as the mobile phase at a flow rate of 1...
February 16, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28231528/identification-of-uv-absorbing-extractables-from-rubber-closures-used-in-containers-of-injectable-powder-and-safety-assessment-of-leachables-in-the-drug
#3
Yulei Wei, Ying Wu, Tingli Zhu, Zhiyan Li, Yilan Zhang
Rubber closures have been of great concern to regulatory authorities on account of their potential safety risks to patients. The aim of our work is to provide part of data about the compatibility of the injectable powder and its packaging materials for the drug registration. In this report, methodologies were established to study the system of the preparation. Firstly, three major extractables were isolated by semi-preparative HPLC method combined with silica gel-based chromatographic methods. NMR spectra including 1D NMR ((1)H, (13)C, DEPT135) and 2D NMR (COSY, HSQC, HMBC) were introduced to identify the extractables, besides HPLC, GC-MS, ESI-MS/MS and HRMS...
February 16, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28231253/community-analysis-of-pigment-patterns-from-37-microalgae-strains-reveals-new-carotenoids-and-porphyrins-characteristic-of-distinct-strains-and-taxonomic-groups
#4
Benoît Serive, Elodie Nicolau, Jean-Baptiste Bérard, Raymond Kaas, Virginie Pasquet, Laurent Picot, Jean-Paul Cadoret
Phytoplankton, with an estimated 30 000 to 1 000 000 species clustered in 12 phyla, presents a high taxonomic and ecophysiological diversity, reflected by the complex distribution of pigments among the different algal classes. High performance liquid chromatography is the gold standard method for qualitative and quantitative analysis of phytoplankton pigments in seawater and culture samples, but only a few pigments can be used as robust chemotaxonomic markers. A major challenge is thus to identify new ones, characteristic of a strain, species, class or taxon that cannot be currently identified on the basis of its pigment signature...
2017: PloS One
https://www.readbyqxmd.com/read/28231162/phenolic-pro%C3%AF-le-and-antioxidant-activity-of-melon-cucumis-melo-l-seeds-from-pakistan
#5
Alam Zeb
Phenolic composition of different extracts of honeydew melon seeds and their antioxidant activity was determined for the first time. Phenolic compounds were identified using a reversed phase high performance liquid chromatography with diode array detection (HPLC-DAD) method. Results showed the identification of five phenolic compounds in water extract namely gallic acid and its derivative, hydroxybenzoic acid and catechin derivatives and caffeic acid.There were nine phenolic compounds identified in methanol-water extract, which are caffeic acid, two vanillic acid derivatives, ellagitanins, quercetin-3-rutinoside, derivatives of syringic acid and ellagic acid...
October 17, 2016: Foods (Basel, Switzerland)
https://www.readbyqxmd.com/read/28231080/oxalate-content-of-taro-leaves-grown-in-central-vietnam
#6
Hang Du Thanh, Hai Phan Vu, Hai Vu Van, Ngoan Le Duc, Tuan Le Minh, Geoffrey Savage
Leaves were harvested from four different cultivars of Colocasia esculenta and three cultivars of Alocasia odora that were growing on nine different farms in central Vietnam. The total, soluble and insoluble oxalate contents of the leaves were extracted and measured using HPLC chromatography. Total calcium determinations were also carried out on the same samples. The total oxalate content of the leaves ranged from 433.8 to 856.1 mg/100 g wet matter (WM) while the soluble oxalate ranged from 147.8 to 339.7 mg/100 g WM...
January 1, 2017: Foods (Basel, Switzerland)
https://www.readbyqxmd.com/read/28231051/short-communication-challenges-relating-to-comparison-of-flavonoid-glycosides-dissolution-profiles-from-sutherlandia-frutescens-products
#7
Oluchi N Mbamalu, James Syce, Halima Samsodien
Unlike the case of conventional drug formulations, dissolution tests have hitherto not been required for herbal medicinal products commercially available in South Africa. This study investigated dissolution of the South African Sutherlandia frutescens using selected flavonoid glycosides as marker compounds. Dissolution of markers was assessed in three dissolution media at pH 1.2, 4.5 and 6.8, and samples were analysed using a validated HPLC method. The dissolution profile of each marker varied for the different materials investigated...
March 1, 2017: Acta Pharmaceutica
https://www.readbyqxmd.com/read/28230805/preparation-of-photoirradiation-molecular-imprinting-polymer-for-selective-separation-of-branched-cyclodextrins
#8
Haoran Fan, Jinpeng Wang, Qingran Meng, Xueming Xu, Tianming Fan, Zhengyu Jin
In the present study, photoirradiation molecularly imprinted polymer (MIP) with azobenzene was used as a functional monomer for the selective separation of the branched cyclodextrins. The functional monomer 4-methacryloyloxy azobenzene (MAA) and the molecular template 6-O-α-d-maltosyl-β-cyclodextrin (G2-β-CD) were implemented for the molecular imprinting. The core-shell structure of photoirradiation MIP was visualized by the transmission electron microscopy (TEM). With Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA), we identified that G2-β-CD was imprinted into the polymer and removed from the MIP...
February 21, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28230759/analysis-of-the-total-biflavonoids-extract-from-selaginella-doederleinii-by-hplc-qtof-ms-and-its-in-vitro-and-in-vivo-anticancer-effects
#9
Hong Yao, Bing Chen, Yanyan Zhang, Huigen Ou, Yuxiang Li, Shaoguang Li, Peiying Shi, Xinhua Lin
Selaginella doederleinii Hieron has been traditionally used as a folk antitumor herbal medicine in China. In this paper, the phytochemical components of the total biflavonoids extract from S. doederleinii were studied by using high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF MS/MS) in negative ion mode, and their in vitro and in vivo anticancer effects were evaluated. Four types of biflavonoids from S. doederleinii, including IC3'-IIC8'', IC3'-IIC6'', IC3'-IIC3''', and C-O linked biflavonoids were examined originally using QTOF MS/MS...
February 20, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28229951/chemical-and-toxicological-characterizations-of-hydraulic-fracturing-flowback-and-produced-water
#10
Yuhe He, Shannon L Flynn, Erik J Folkerts, Yifeng Zhang, Dongliang Ruan, Daniel S Alessi, Jonathan W Martin, Greg G Goss
Hydraulic fracturing (HF) has emerged as a major method of unconventional oil and gas recovery. The toxicity of hydraulic fracturing flowback and produced water (HF-FPW) has not been previously reported and is complicated by the combined complexity of organic and inorganic constituents in HF fluids and deep formation water. In this study, we characterized the solids, salts, and organic signatures in an HF-FPW sample from the Duvernay Formation, Alberta, Canada. Untargeted HPLC-Orbitrap revealed numerous unknown dissolved polar organics...
February 14, 2017: Water Research
https://www.readbyqxmd.com/read/28229941/dual-high-resolution-inhibition-profiling-and-hplc-hrms-spe-nmr-analysis-for-identification-of-%C3%AE-glucosidase-and-radical-scavenging-inhibitors-in-solanum-americanum-mill
#11
Eder L Silva, Rita C Almeida-Lafetá, Ricardo M Borges, Dan Staerk
Solanum americanum is one of the most prominent species used to treat type 2 diabetes in Guatemala. In our ongoing efforts to find antidiabetic and antioxidative compounds from natural sources, an ethyl acetate extract of this medicinal herb was investigated using dual high-resolution α-glucosidase/radical scavenging inhibition profiling. The high-resolution biochromatograms obtained by this technique were used to target subsequent structural elucidation by HPLC-HRMS-SPE-NMR analysis towards the bioactive constituents...
February 13, 2017: Fitoterapia
https://www.readbyqxmd.com/read/28229922/mandevilla-longiflora-desf-pichon-improves-airway-inflammation-in-a-murine-model-of-allergic-asthma
#12
Danielle Ayr Tavares de Almeida, Suellen Iara Guirra Rosa, Thais Campos Dias da Cruz, Eduarda Pavan, Amílcar Sabino Damazo, Ilsamar Mendes Soares, Sérgio Donizeti Ascêncio, Antonio Macho, Domingos Tabajara de Oliveira Martins
ETHNOPHARMACOLOGICAL RELEVANCE: Mandevilla longiflora, popularly known as "velame" in central Brazil, is a subshrub and widely distributed in South America. Its xylopodium is used in the form of a decoction or infusion to treat inflammation and other ailments. AIM OF THE STUDY: This study aimed to evaluate the anti-inflammatory potential of M. longiflora in an in vivo model of ovalbumin-induced immediate hypersensitivity, identifying its effects on leukocyte infiltration, IgE and LTB4 levels, and Th2 cytokine production...
February 13, 2017: Journal of Ethnopharmacology
https://www.readbyqxmd.com/read/28226292/hplc-dad-qtof-ms-profiling-of-phenolics-from-leaf-extracts-of-two-tunisian-fig-cultivars-potential-as-a-functional-food
#13
Olfa Belguith-Hadriche, Sonda Ammar, María Del Mar Contreras, Hamadi Fetoui, Antonio Segura-Carretero, Abdelfattah El Feki, Mohamed Bouaziz
The phenolic constituents of the aqueous-ethanolic extract of two Tunisian Ficus carica leaves cultivars and their hypoglycaemic, hypolipidaemic and antioxidative activities in alloxan-induced diabetic rats were investigated. Our results demonstrated that the treatment with the leaves extracts of F. carica improved lipid profile and reduced blood glucose level as well as thiobarbituric acid-reactive substances content. The antioxidant enzymes activity in the liver and heart tissues of diabetic rats was increased after the treatment...
February 19, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28226282/systematic-identification-of-flavonols-flavonol-glycosides-triterpene-and-siraitic-acid-glycosides-from-siraitia-grosvenorii-using-high-performance-liquid-chromatography-quadrupole-time-of-flight-mass-spectrometry-combined-with-a-screening-strategy
#14
Zhi-Xing Qing, Huan Zhao, Qi Tang, Chang-Ming Mo, Peng Huang, Pi Cheng, Peng Yang, Xue-Yi Yang, Xiu-Bin Liu, Ya-Jie Zheng, Jian-Guo Zeng
The fruits of Siraitia grosvenorii are considered to be health-promoting because of the diversity of their bioactive ingredients. In the present study, a screening method, using high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (HPLC-Q-TOF-MS) combined with a screening strategy, has been established. The technology was used to systematically screening the targeted metabolites, primarily from the complex matrix of S. grosvenorii. The compounds were then identified by their exact masses and characteristic fragment ions, in comparison with the fragmentation behaviors of 19 references...
February 16, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28226278/quantitative-methylene-blue-decolourisation-assays-as-rapid-screening-tools-for-assessing-the-efficiency-of-catalytic-reactions
#15
Jan Kruid, Ronen Fogel, Janice Leigh Limson
Identifying the most efficient oxidation process to achieve maximum removal of a target pollutant compound forms the subject of much research. There exists a need to develop rapid screening tools to support research in this area. In this work we report on the development of a quantitative assay as a means for identifying catalysts capable of decolourising methylene blue through the generation of oxidising species from hydrogen peroxide. Here, a previously described methylene blue test strip method was repurposed as a quantitative, aqueous-based spectrophotometric assay...
February 12, 2017: Chemosphere
https://www.readbyqxmd.com/read/28226182/effect-of-different-solvents-on-the-measurement-of-phenolics-and-the-antioxidant-activity-of-mulberry-morus-atropurpurea-roxb-with-accelerated-solvent-extraction
#16
Jiufang Yang, XiaoQun Ou, Xiaoxu Zhang, ZiYing Zhou, LiYan Ma
The effects of 9 different solvents on the measurement of the total phenolics and antioxidant activities of mulberry fruits were studied using accelerated solvent extraction (ASE). Sixteen to 22 types of phenolics (flavonols, flavan-3-ols, flavanol, hydroxycinnamic acids, hydroxybenzoic acids, and stilbenes) from different mulberry extracts were characterized and quantified using HPLC-MS/MS. The principal component analysis (PCA) was used to determine the suitable solvents to distinguish between different classes of phenolics...
February 22, 2017: Journal of Food Science
https://www.readbyqxmd.com/read/28225164/effects-of-focal-brain-cooling-on-extracellular-concentrations-of-neurotransmitters-in-patients-with-epilepsy
#17
Sadahiro Nomura, Takao Inoue, Hirochika Imoto, Eiichi Suehiro, Yuichi Maruta, Yuya Hirayama, Michiyasu Suzuki
OBJECTIVE: Brain hypothermia controls epileptic discharge and reduces extracellular concentrations of glutamate (Glu), an excitatory neurotransmitter. We aimed to determine the effects of focal brain cooling (FBC) on levels of γ-aminobutyric acid (GABA), which is a major inhibitory neurotransmitter. The relationship between Glu or GABA concentrations and the severity of epileptic symptoms was also analyzed. METHODS: Patients with intractable epilepsy underwent FBC at lesionectomized (n = 11) or hippocampectomized (n = 8) regions at 15°C for 30 min using custom-made cooling devices...
February 22, 2017: Epilepsia
https://www.readbyqxmd.com/read/28224643/endophytic-phomopsis-sp-colonization-in-oryza-sativa-was-found-to-result-in-plant-growth-promotion-and-piperine-production
#18
Chithra S, Jasim B, Jyothis Mathew, Radhakrishnan E K
Endophytic fungi have been reported to have the acquired ability to synthesize host plant specific medicinal natural products. Many fungi with such properties have been characterized and optimized for the conditions which favor maximal production of desired products. However, the inherent plant colonization property of promising endophytic fungi is least studied. Exploiting the transgenome functioning of these fungi have immense applications to add beneficial features to non-host plants. In the present study, endophytic fungus Phomopsis sp...
February 22, 2017: Physiologia Plantarum
https://www.readbyqxmd.com/read/28224249/signal-enhancement-in-the-hplc-esi-ms-ms-analysis-of-spironolactone-and-its-metabolites-using-hfip-and-nh4f-as-eluent-additives
#19
Kalev Takkis, Rudolf Aro, Lenne-Triin Kõrgvee, Heili Varendi, Jana Lass, Koit Herodes, Karin Kipper
This paper describes an LC-MS/MS method to determine the concentration of spironolactone and its metabolites 7-alpha-methylthiospironolactone and canrenone in blood plasma samples. The resulting assay is simple (using protein precipitation for sample preparation) and sensitive (the lower limit of quantification is close to 0.5 ng/ml) while requiring only 50 μl of plasma, making it especially suitable for analyzing samples obtained from pediatric and neonatal patients where sample sizes are limited. The sensitivity is achieved by using ammonium fluoride as an eluent additive, which in our case amplifies the signal from our analytes in the plasma solution on average about 70 times...
February 21, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28224246/comparison-of-veterinary-drug-residue-results-in-animal-tissues-by-ultrahigh-performance-liquid-chromatography-coupled-to-triple-quadrupole-or-quadrupole-time-of-flight-tandem-mass-spectrometry-after-different-sample-preparation-methods-including-use-of-a-commercial
#20
Tarun Anumol, Steven J Lehotay, Joan Stevens, Jerry Zweigenbaum
Veterinary drug residues in animal-derived foods must be monitored to ensure food safety, verify proper veterinary practices, enforce legal limits in domestic and imported foods, and for other purposes. A common goal in drug residue analysis in foods is to achieve acceptable monitoring results for as many analytes as possible, with higher priority given to the drugs of most concern, in an efficient and robust manner. The U.S. Department of Agriculture has implemented a multiclass, multi-residue method based on sample preparation using dispersive solid phase extraction (d-SPE) for cleanup and ultrahigh-performance liquid chromatography-tandem quadrupole mass spectrometry (UHPLC-QQQ) for analysis of >120 drugs at regulatory levels of concern in animal tissues...
February 21, 2017: Analytical and Bioanalytical Chemistry
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