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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
#1
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/28226292/hplc-dad-qtof-ms-profiling-of-phenolics-from-leaf-extracts-of-two-tunisian-fig-cultivars-potential-as-a-functional-food
#2
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/28224912/high-throughput-screening-and-quantitation-of-guanidino-and-ureido-compounds-using-liquid-chromatography-drift-tube-ion-mobility-spectrometry-mass-spectrometry
#3
Ruo-Jing Fan, Fang Zhang, Xiu-Ping Chen, Wan-Shu Qi, Qing Guan, Tuan-Qi Sun, Yin-Long Guo
The present work focused on the high-throughput screening and quantitation of guanidino compounds (GCs) and ureido compounds (UCs) in human thyroid tissues. The strategy employed benzylic rearrangement stable isotope labeling (BRSIL) for the sample preparation and then detection using liquid chromatography-drift tube ion mobility spectrometry-quadrupole time of flight mass spectrometry (LC-DTIMS-QTOF MS). A short reversed-phase LC realized an on-line desalting and a measurement cycle of 5.0 min. DTIMS separation enhanced the better specificity and selectivity for the benzil labeled GCs and UCs...
April 8, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28218842/medium-chain-chlorinated-paraffins-cps-dominate-in-australian-sewage-sludge
#4
Sicco Hendrik Brandsma, Louise van Mourik, Jake William O'Brien, Geoff Eaglesham, Pim E G Leonards, Jacob De Boer, Christie Gallen, Jochen F Mueller, Caroline Gaus, Christian Bogdal
To simultaneously quantify and profile the complex mixture of short-, median-, and long-chain CPs (SCCPs, MCCPs and LCCPs) in Australian sewage sludge, we applied and further validated a recently developed novel instrumental technique, using quadrupole time-of-flight high resolution mass spectrometry running in the negative atmospheric pressure chemical ionization mode (APCI-qTOF-HRMS). Without using an analytical column the cleaned extracts were directly injected into the qTOF-HRMS followed by quantification of the CPs by a mathematical algorithm...
February 20, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28215546/analysis-of-human-serum-metabolome-for-potential-biomarkers-identification-of-erosive-oral-lichen-planus
#5
Xu-Yan Yang, Shuai-Nan Zhang, Xu-Zhao Li, Yu Wang, Xiao-Dong Yin
BACKGROUND: Oral lichen planus (OLP) is a chronic auto-inflammatory mucositis and potentially oral premalignant lesion. Erosive OLP patients display the higher canceration rate as compared to the patients with non-erosive OLP. Identification of the potential biomarkers associated with erosive OLP may help to investigate the disease pathogenesis and to improve clinical treatment. METHODS: Ultra-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF-MS) combined with pattern recognition approaches were integrated to acquire differentially expressed metabolites for the pathways analysis and elucidate mechanisms of disease...
February 16, 2017: Clinica Chimica Acta; International Journal of Clinical Chemistry
https://www.readbyqxmd.com/read/28214647/fate-of-antimicrobials-in-duckweed-lemna-minor-wastewater-treatment-systems
#6
Evangelia I Iatrou, Georgia Gatidou, Dimitrios Damalas, Nikolaos S Thomaidis, Athanasios S Stasinakis
The fate of four antimicrobials (cefadroxil, CFD; metronidazole, METRO; trimethoprim, TRI; sulfamethoxazole, SMX) was studied in Lemna minor systems and the role of different mechanisms on their removal was evaluated. All micropollutants were significantly removed in batch experiments with active Lemna minor; the highest removal was observed for CFD (100% in 14 d), followed by METRO (96%), SMX (73%) and TRI (59%) during 24 d of the experiment. Calculation of kinetic constants for hydrolysis, photodegradation, sorption to biomass and plant uptake revealed significant differences depending on the compound and the studied mechanism...
February 13, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28210755/assessment-of-quinoxyfen-phototransformation-pathways-by-liquid-chromatography-coupled-to-accurate-mass-spectrometry
#7
Priscila Ferri, María Ramil, Isaac Rodríguez, Rosângela Bergamasco, Angélica Marquetotti Salcedo Vieira, Rafael Cela
Quinoxyfen has been recently identified as a priority hazardous substance in the field of the European water policy. In this work, its fate in aqueous samples and solid supports under UV and solar radiation is investigated. Diverse degradation experiments were carried out, at lab scale, using spiked aliquots of different aqueous matrices (ultrapure, treated wastewater and river water) irradiated at different wavelengths (λ = 254 nm, λ = 365 nm and solar light). Half-lives of quinoxyfen (2-26 min) depended on the wavelength and the intensity of radiation whilst the nature of the aqueous matrix did not play an important role in degradation kinetics...
February 16, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28208630/cocoa-and-grape-seed-byproducts-as-a-source-of-antioxidant-and-anti-inflammatory-proanthocyanidins
#8
María De La Luz Cádiz-Gurrea, Isabel Borrás-Linares, Jesús Lozano-Sánchez, Jorge Joven, Salvador Fernández-Arroyo, Antonio Segura-Carretero
Phenolic compounds, which are secondary plant metabolites, are considered an integral part of the human diet. Physiological properties of dietary polyphenols have come to the attention in recent years. Especially, proanthocyanidins (ranging from dimers to decamers) have demonstrated potential interactions with biological systems, such as antiviral, antibacterial, molluscicidal, enzyme-inhibiting, antioxidant, and radical-scavenging properties. Agroindustry produces a considerable amount of phenolic-rich sources, and the ability of polyphenolic structures to interacts with other molecules in living organisms confers their beneficial properties...
February 10, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28208272/ion-elevators-and-escalators-in-multilevel-structures-for-lossless-ion-manipulations
#9
Yehia M Ibrahim, Ahmed M Hamid, Jonathan T Cox, Sandilya V B Garimella, Richard D Smith
We describe two approaches based upon ion "elevator" and "escalator" components that allow moving ions to different levels in structures for lossless ion manipulations (SLIM). Guided by ion motion simulations, we designed elevator and escalator components based upon ion current measurements providing essentially lossless transmission in multilevel designs. The ion elevator design allowed ions to efficiently bridge a 4 mm gap between levels. The component was integrated in a SLIM and coupled to a QTOF mass spectrometer using an ion funnel interface to evaluate the m/z range transmitted as compared to transmission within a level (e...
February 7, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28207195/increasing-the-linear-dynamic-range-in-lc-ms-is-it-valid-to-use-a-less-abundant-isotopologue
#10
Stephen Trobbiani, Peter Stockham, Timothy Scott
Liquid chromatography/mass spectrometry (LC/MS) has quickly become the analytical method of choice in forensic toxicology laboratories due to its ability to detect a very wide range of compounds in a single analysis. One of the major limitations of LC/MS however, is a relatively limited linear dynamic range for quantitation. A new approach to combating this problem is to use the [(+1) M + H](+) isotope mass peak for quantitation, thereby reducing saturation at the detector and extending the linear range...
February 16, 2017: Drug Testing and Analysis
https://www.readbyqxmd.com/read/28204488/correction-to-simultaneous-screening-and-quantification-of-basic-neutral-and-acidic-drugs-in-blood-using-uplc-qtof-ms
#11
Sergei Bidny, Kim Gago, Phuong Chung, Desdemona Albertyn, Daniel Pasin
No abstract text is available yet for this article.
February 16, 2017: Journal of Analytical Toxicology
https://www.readbyqxmd.com/read/28199916/isolation-of-four-phenolic-compounds-from-mangifera-indica-l-flowers-by-using-normal-phase-combined-with-elution-extrusion-two-step-high-speed-countercurrent-chromatography
#12
Nusrat Shaheen, Yanzhen Lu, Ping Geng, Qian Shao, Yun Wei
Two-step high speed countercurrent chromatography method, following normal phase and elution-extrusion mode of operation by using selected solvent systems, was introduced for phenolic compounds separation. Phenolic compounds including gallic acid, ethyl gallate, ethyl digallate and ellagic acid were separated from the ethanol extract of mango (Mangifera indica L.) flowers for the first time. In the first step, gallic acid of 3.7mg and ethyl gallate of 3.9mg with the purities of 98.87% and 99.55%, respectively, were isolated by using hexane-ethylacetate-methanol-water (4:6:4:6, v/v) in normal phase high speed countercurrent chromatography from 200mg of crude extract, while ethyl digallate and ellagic acid were collected in the form of mixture fraction...
January 15, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28196344/identification-characterization-and-in-silico-admet-prediction-of-roflumilast-degradation-products
#13
Mariana S Pinheiro, Gil M Viana, Bárbara de A Abrahim Vieira, Alessandra Mendonça Teles de Souza, Carlos Rangel Rodrigues, Rita de Cássia E E Marins, Lúcio M Cabral, Valéria P de Sousa
The present study reports the degradation behavior of roflumilast (RFL), a new drug developed for the treatment of chronic obstructive pulmonary disease. The degradation of RFL was tested under various stress conditions as per the guidelines of the International Conference on Harmonization. The degradation products (DPs) of RFL were identified, characterized and in silico predictions were made of their pharmacokinetic properties, absorption, distribution, metabolism, excretion and toxicity (ADMET). RFL was subjected to various stress conditions including photodegradation, alkaline and acidic hydrolysis, oxidative and metallic degradation...
February 6, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28193433/antioxidant-profiling-of-vine-tea-ampelopsis-grossedentata-off-line-coupling-heart-cutting-hsccc-with-hplc-dad-qtof-ms-ms
#14
Qingping Gao, Ruyi Ma, Lin Chen, Shuyun Shi, Ping Cai, Shuihan Zhang, Haiyan Xiang
Vine tea with strong antioxidant activity is commonly consumed as healthy tea/beverage. However, detailed information about its antioxidants is incomplete. Here, off-line hyphenation of heart-cutting high-speed countercurrent chromatography (HSCCC) with high performance liquid chromatography-diode array detector-quadrupole time-of-flight tandem mass spectrometry (HPLC-DAD-QTOF-MS/MS) were described for systematic profiling antioxidants in vine tea. At first, antioxidants were rapidly screened by 1,1-diphenyl-2-picryl-hydrazyl radical-high performance liquid chromatography (DPPH-HPLC)...
June 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28193030/dynamic-cluster-analysis-an-unbiased-method-for-identifying-a-2-element-containing-compounds-in-liquid-chromatographic-high-resolution-time-of-flight-mass-spectrometric-data
#15
Aaron John Christian Andersen, Per Juel Hansen, Kevin Jørgensen, Kristian Fog Nielsen
Dynamic cluster analysis (DCA) is an automated, unbiased technique which can identify Cl, Br, S, and other A + 2 element containing metabolites in liquid chromatographic high-resolution mass spectrometric data. DCA is based on three features, primarily the previously unutilized A + 1 to A + 2 isotope cluster spacing which is a strong classifier in itself but improved with the addition of the monoisotopic mass, and the well-known A:A+2 intensity ratio. Utilizing only the A + 1 to A + 2 isotope cluster spacing and the monoisotopic mass it was possible to filter a chromatogram for metabolites which contain Cl, Br, and S...
December 20, 2016: Analytical Chemistry
https://www.readbyqxmd.com/read/28192997/photolysis-of-antibiotics-under-simulated-sunlight-irradiation-identification-of-photoproducts-by-high-resolution-mass-spectrometry
#16
Rosa María Baena-Nogueras, Eduardo Gonzalez-Mazo, Pablo Antonio Lara-Martín
There is a growing concern on the widespread use of antibiotics and their presence in the aqueous environment. Their removal in the water column is mediated by different types of degradation processes for which the mechanisms are still unclear. This research is focused on characterizing the photodegradation kinetics and pathways of two largely employed antibiotics families: sulfonamides (9 SDs) and fluoroquinolones (6 FQs). Degradation percentages and rates were measured in pure water exposed to simulated natural sunlight at a constant irradiance value (500 W m-2) during all the experiments, and the main photoproducts formed were characterized through accurate mass measurement using ultra-performance liquid chromatography - quadrupole-time-of-flight - mass spectrometry (UPLC-QToF-MS)...
February 14, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28191951/rearranged-terpenoids-from-the-marine-sponge-darwinella-cf-oxeata-and-its-predator-the-nudibranch-felimida-grahami
#17
Maria Camila A Ramirez, David E Williams, Juliana R Gubiani, Lizbeth L L Parra, Mario F C Santos, Daiane D Ferreira, Juliana T Mesquita, Andre G Tempone, Antonio G Ferreira, Vinícius Padula, Eduardo Hajdu, Raymond J Andersen, Roberto G S Berlinck
Marine sponges are a rich source of terpenoids with rearranged spongian carbon skeletons. Investigation of extracts from the sponge Darwinella cf. oxeata yielded four new rearranged diterpenoids, oxeatine (2) and oxeatamides H-J (3-5), as well as the known metabolites oxeatamide A (6), oxeatamide A methyl ester (7), and membranolide (1). Oxeatine (2) has a new heterocyclic skeleton, while oxeatamide J (5) has an N-methyl urea group included in a γ-lactam moiety. UPLC-QTOF analysis of the extract obtained from the mantle of the nudibranch Felimida grahami indicated the presence of 1 and 4...
February 13, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28184241/thermal-degradation-of-aqueous-2-aminoethylethanolamine-in-co2-capture-identification-of-degradation-products-reaction-mechanisms-and-computational-studies
#18
Idris Mohamed Saeed, Vannajan Sanghiran Lee, Shaukat Ali Mazari, B Si Ali, Wan Jeffrey Basirun, Anam Asghar, Lubna Ghalib, Badrul Mohamed Jan
Amine degradation is the main significant problems in amine-based post-combustion CO2 capture, causes foaming, increase in viscosity, corrosion, fouling as well as environmental issues. Therefore it is very important to develop the most efficient solvent with high thermal and chemical stability. This study investigated thermal degradation of aqueous 30% 2-aminoethylethanolamine (AEEA) using 316 stainless steel cylinders in the presence and absence of CO2 for 4 weeks. The degradation products were identified by gas chromatography mass spectrometry (GC/MS) and liquid chromatography-time-of-flight-mass spectrometry (LC-QTOF/MS)...
2017: Chemistry Central Journal
https://www.readbyqxmd.com/read/28182113/evaluation-of-an-aqueous-extract-from-horseradish-root-armoracia-rusticana-radix-against-lipopolysaccharide-induced-cellular-inflammation-reaction
#19
Corinna Herz, Hoai Thi Thu Tran, Melinda-Rita Márton, Ronald Maul, Susanne Baldermann, Monika Schreiner, Evelyn Lamy
Horseradish (Armoracia rusticana) is a perennial crop and its root is used in condiments. Traditionally, horseradish root is used to treat bacterial infections of the respiratory tract and urinary bladder. The antiphlogistic activity, determined in activated primary human peripheral blood mononuclear cells (PBMC), was evaluated for an aqueous extract and its subfractions, separated by HPLC. Compound analysis was done by UHPLC-QToF/MS and GC-MS. The aqueous extract concentration-dependently inhibited the anti-inflammatory response to lipopolysaccharide (LPS) in terms of TNF-α release at ≥37 μg/mL...
2017: Evidence-based Complementary and Alternative Medicine: ECAM
https://www.readbyqxmd.com/read/28178753/chemical-composition-differentiation-of-shen-shuai-ning-granule-between-combined-decoction-and-separated-decoction-using-hplc-dad-esi-qtof-ms
#20
Jianli Liu, Yu Zhang, Yimeng Hao, Ying Zhao, Yanjiao Li, Rulan Qin, Chongning Lv, Jincai Lu
Shen-Shuai-Ning (SSN) granule, a traditional Chinese medicine formula is widely used in clinical practice for treating chronic renal failure. However, detailed chemical profile about it was unknown. Here, HPLC-ESI-QTOF-MS was employed for the systematic chemical analysis of SSN. A total of 52 compounds were identified and the characteristic ions of compounds were described. Furthermore, chemical consistency between combined decoction and separated decoction of SSN was evaluated using HPLC-DAD. The chemical comparison between two preparations of SSN granule (combined decoction and separated decoction of Coptides Rhizoma) indicated a significant difference in content of many compounds including Salvianolic acid A, Salvianolic acid B, Berberine, Palmatine and Epiberberine...
February 8, 2017: Biomedical Chromatography: BMC
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