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https://www.readbyqxmd.com/read/29351264/identification-of-cyclic-dipeptides-from-escherichia-coli-as-new-antimicrobial-agents-against-ralstonia-solanacearum
#1
Shihao Song, Shuna Fu, Xiuyun Sun, Peng Li, Ji'en Wu, Tingyan Dong, Fei He, Yinyue Deng
Ralstonia solanacearum is a causative agent of bacterial wilt in many important crops throughout the world. How to control bacterial wilt caused by R. solanacearum is a major problem in agriculture. In this study, we aim to isolate the biocontrol agents that have high efficacy in the control of bacterial wilt. Three new bacterial strains with high antimicrobial activity against R. solanacearum GMI1000 were isolated and identified. Our results demonstrated that these bacteria could remarkably inhibit the disease index of host plant infected by R...
January 19, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29350439/tandem-mass-spectroscopy-as-a-tool-for-investigation-of-complexes-of-pnp-lariat-ether-derivative-with-metals-ions
#2
Natalia Gutowska, Piotr Seliger, Grzegorz Andrijewski, Grażyna Adamus, Iwona Kwiecień
The novel PNP-lariat ether L with cyclotriphosphazene ring incorporated in the macrocyclic structure was synthesized and checked by the ESI-MS method for the ability to bind different types of ions Ag+ , Ca2+ , Cd2+ , Cu2+ and Pb2+ . Furthermore, the stability constants of the abovementioned ions complexes with the investigated ligand have been determined by direct and competitive potentiometric methods. In order to evaluate the stability of various complexes types and to confirm the way of metal cation binding, the tandem mass spectra (MS/MS) of the investigated ligand and its complexes were taken...
January 19, 2018: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/29350358/streptomyces-ach-505-triggers-production-of-a-salicylic-acid-analogue-in-the-fungal-pathogen-heterobasidion-abietinum-that-enhances-infection-of-norway-spruce-seedlings
#3
Nadine Keilhofer, Jonny Nachtigall, Andreas Kulik, Margret Ecke, Rüdiger Hampp, Roderich D Süssmuth, Hans-Peter Fiedler, Silvia D Schrey
The necrotrophic fungus Heterobasidion spp. is the causal agent of 'annosum root rot' of Norway spruce. In the presence of the rhizosphere bacterium Streptomyces AcH 505, enhanced colonization of Norway spruce roots with Heterobasidion abietinum 331 has previously been observed. By analyzing dual cultures of H. abietinum 331 and Streptomyces AcH 505 with HPLC, a fungal metabolite was identified that was increased in the presence of Streptomyces AcH 505. Likewise, challenge of H. abietum 331 with common antifungals produced by soil streptomycetes rendered the same effect...
January 19, 2018: Antonie Van Leeuwenhoek
https://www.readbyqxmd.com/read/29350256/analysis-of-phenolic-compounds-in-different-parts-of-pomegranate-punica-granatum-fruit-by-hplc-pda-esi-ms-and-evaluation-of-their-antioxidant-activity-application-to-different-italian-varieties
#4
Marina Russo, Chiara Fanali, Giusy Tripodo, Paola Dugo, Rosario Muleo, Laura Dugo, Laura De Gara, Luigi Mondello
The analysis of pomegranate phenolic compounds belonging to different classes in different fruit parts was performed by high-performance liquid chromatography coupled with photodiode array and mass spectrometry detection. Two different separation methods were optimized for the analysis of anthocyanins and hydrolyzable tannins along with phenolic acids and flavonoids. Two C18 columns, core-shell and fully porous particle stationary phases, were used. The parameters for separation of phenolic compounds were optimized considering chromatographic resolution and analysis time...
January 19, 2018: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/29350053/8-isopentenyl-isoflavone-derivatives-from-the-whole-herb-of-sphaerophysa-salsula
#5
Li-Jin Jiao, Wei-Dong Wang, Yan-Duo Tao, Yun Shao, Li-Juan Mei, Zeng-Gen Liu, Qi-Lan Wang, Jun Dang
Phytochemical studies on the whole herb of Sphaerophysa salsula has resulted in the discovery of one new 8-isopentenyl isoflavone derivative, named sphaerosin s2 (3-(8-(2-hydroxypropan-2-yl)-3,4-dihydro-2H-furo[2,3-h]chromen-3-yl)-2,6-dimethoxyphenol) (1), along with four know 8-isopentenyl isoflavone derivatives (2-5). Compounds (2, 4 and 5) were isolated for the first time from this species. Their structures were elucidated on the basis of ESI-MS, UV, IR, 1D NMR and 2D NMR data.
January 19, 2018: Natural Product Research
https://www.readbyqxmd.com/read/29348529/two-new-lankacidin-related-metabolites-from-streptomyces-sp-hs-nf-1178
#6
Chang Lu, Jin-Meng Li, Huan Qi, Hui Zhang, Ji Zhang, Wen-Sheng Xiang, Ji-Dong Wang, Xiang-Jing Wang
Two new lankacidin-related metabolites, 2,18-seco-lankacidinol A (1), 2,18-seco-lankacidinol B (2) and a known compound, lankacidinol (3), were isolated from the fermentation broth of Streptomyces sp. HS-NF-1178. Their structures were determined on the basis of spectroscopic analysis, including 1D and 2D NMR techniques as well as ESI-MS and comparison with data from the literature. These two new compounds, especially compound 1, exhibited potent antitumor activity.
January 18, 2018: Journal of Antibiotics
https://www.readbyqxmd.com/read/29348048/identification-of-number-and-type-of-cations-in-water-soluble-cs-and-na-calix-4-arene-bis-crown-6-complexes-by-using-esi-tof-ms
#7
Shogo Kumagai, Kotaro Hayashi, Tomohito Kameda, Naoya Morohashi, Tetsutaro Hattori, Toshiaki Yoshioka
The treatment of cesium-contaminated wastewater has become one of the biggest issues. The selective Cs+ removal from wastewater containing competitive alkali metal ions such as Na+ is desired to reduce the volume of sludge. Therefore, the present work focused on water-soluble calix[4]arene-bis-crown-6 (W-BisC6) to selectively capture Cs+. For characterization of the complex, UV-vis spectroscopy is commonly used, however, due to the limited availability of information it can be hard to quickly identify the specific structures of some complexes...
January 11, 2018: Chemosphere
https://www.readbyqxmd.com/read/29347842/in-vitro-antioxidant-potential-and-in-vivo-effects-of-schinus-terebinthifolia-raddi-leaf-extract-in-diabetic-rats-and-determination-of-chemical-composition-by-hplc-esi-ms-ms
#8
Camila Cristina Iwanaga, Lilian Dos Anjos Oliveira Ferreira, Karine Zanoli Bernuci, Carla Maria Mariano Fernandez, Fabiana Brusco Lorenzetti, Camila Caviquioli Sehaber, Flávia Cristina Vieira Frez, Sara Santos Bernardes, Gean Pier Panizzon, Giani Andrea Linde, Maria do Carmo Vieira, Jacqueline Nelisis Zanoni, Diógenes Aparício Garcia Cortez
The present study investigated the in vitro and in vivo antioxidant potential and phytochemical composition of Schinus terebinthifolia, which is widely used in folk medicine for various therapeutic purposes. The in vitro analyses indicated that the hydroethanolic extract (HE) had 312.50 ± 0.50 mg GAE/g of total phenols. It also presented anti-DPPH• and anti-ABTS•+ activity, reduced phosphomolybden and metal ions and blocked the bleaching of β-carotene. The HE at concentrations of 3.0 and 2.0 μg/mL had TRAP values of 2...
January 18, 2018: Natural Product Research
https://www.readbyqxmd.com/read/29346327/enhanced-isotopic-ratio-outlier-analysis-iroa-peak-detection-and-identification-with-ultra-high-resolution-gc-orbitrap-ms-potential-application-for-investigation-of-model-organism-metabolomes
#9
Yunping Qiu, Robyn D Moir, Ian M Willis, Suresh Seethapathy, Robert C Biniakewitz, Irwin J Kurland
Identifying non-annotated peaks may have a significant impact on the understanding of biological systems. In silico methodologies have focused on ESI LC/MS/MS for identifying non-annotated MS peaks. In this study, we employed in silico methodology to develop an Isotopic Ratio Outlier Analysis (IROA) workflow using enhanced mass spectrometric data acquired with the ultra-high resolution GC-Orbitrap/MS to determine the identity of non-annotated metabolites. The higher resolution of the GC-Orbitrap/MS, together with its wide dynamic range, resulted in more IROA peak pairs detected, and increased reliability of chemical formulae generation (CFG)...
January 18, 2018: Metabolites
https://www.readbyqxmd.com/read/29343620/comparative-extractables-study-of-autoclavable-polyethersulfone-filter-cartridges-for-sterile-filtration
#10
Roberto Menzel, Ina Pahl, Thomas Loewe, Armin Hauk
Sterile filters are ubiquitous in biopharmaceutical manufacturing processes. Since such filters are in direct contact with the process fluid, profiling of the extractables is of utmost importance. The work presented here reveals the extractables profile from filter cartridges for sterilizing grade filtration, which were obtained from six different vendors. All filters contain a 0.2 μm polyethersulfone (PES) membrane for sterile filtration combined with a PES pre-filter with retention rates spanning from 0...
January 17, 2018: PDA Journal of Pharmaceutical Science and Technology
https://www.readbyqxmd.com/read/29342936/structure-characterization-of-honey-processed-astragalus-polysaccharides-and-its-anti-inflammatory-activity-in-vitro
#11
Jingzhu Liao, Chanyi Li, Jing Huang, Wuping Liu, Hongce Chen, Shuangye Liao, Hongyuan Chen, Wen Rui
Honey-processed Astragalus is a dosage form of Radix Astragalus mixed with honey by a traditional Chinese medicine processing method which strengthens the tonic effect. Astragalus polysaccharide (APS), perform its immunomodulatory effects by relying on the tonic effect of Radix Astragalus, therefore, the improved pharmacological activity of honey-processed Astragalus polysaccharide (HAPS) might be due to structural changes during processing. The molecular weights of HAPS and APS were 1,695,788 Da, 2,047,756 Da, respectively, as determined by high performance gel filtration chromatography combined with evaporative light scattering detection (HPGFC-ELSD)...
January 15, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29340956/semi-targeted-analysis-of-complex-matrices-by-esi-ft-icr-ms-or-how-an-experimental-bias-may-be-used-as-an-analytical-tool
#12
Jasmine Hertzog, Vincent Carré, Anthony Dufour, Frédéric Aubriet
Ammonia is well suited to favor deprotonation process in electrospray ionization mass spectrometry (ESI-MS) to increase the formation of [M - H]-. Nevertheless, NH3 may react with carbonyl compounds (aldehyde, ketone) and bias the composition description of the investigated sample. This is of significant importance in the study of complex mixture such as oil or bio-oil. To assess the ability of primary amines to form imines with carbonyl compounds during the ESI-MS process, two aldehydes (vanillin and cinnamaldehyde) and two ketones (butyrophenone and trihydroxyacetophenone) have been infused in an ESI source with ammonia and two different amines (aniline and 3-chloronaniline)...
January 16, 2018: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/29339413/proteotranscriptomic-analysis-and-discovery-of-the-profile-and-diversity-of-toxin-like-proteins-in-centipede
#13
Feng Zhao, Xinqiang Lan, Tao Li, Yang Xiang, Fang Zhao, Yun Zhang, Wenhui Lee
Centipedes are one of the oldest venomous animals and use their venoms as weapons to attack prey or protect themselves. Their venoms contain various components with different biomedical and pharmacological properties. However, little attention has been paid to the profiles and diversity of their toxin-like proteins/peptides. In this study, we used a proteotranscriptomic approach to uncover the diversity of centipede toxin-like proteins in Scolopendra subspinipes mutilans Nine hundred twenty-three and 6,736 peptides, which were separately isolated from venom and torso tissues, respectively, were identified by ESI-MS/MS and deduced from their transcriptomes...
January 16, 2018: Molecular & Cellular Proteomics: MCP
https://www.readbyqxmd.com/read/29338668/simultaneous-determination-of-afidopyropen-and-its-metabolite-in-vegetables-fruit-and-soil-using-uhplc-ms-ms
#14
Kaiying Chen, Xingang Liu, Xiaohu Wu, Fengshou Dong, Jun Xu, Yongquan Zheng
A new analytical method using the quick, easy, cheap, effective, rugged and safe (QuEChERS) procedure for simultaneous determination of afidopyropen and its metabolite M440I007 residues in tomato, watermelon, pepper, cucumber, pear, grape, cabbage and soil samples was developed using ultra-high performance liquid chromatography coupled with tandem mass spectrometry. The target compound was determined in less than 5.0 min using an electrospray ionisation source in positive mode (ESI+). The limit of quantification was 1 μg kg-1 in different matrices...
January 17, 2018: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/29337381/a-combined-photochemical-and-multi-component-reaction-approach-to-precision-oligomers
#15
Waldemar Konrad, Fabian Raphael Blößer, Katharina Wetzel, Andreas Boukis, Michael Meier, Christopher Barner-Kowollik
We introduce an avenue for the convergent synthesis of linear monodisperse sequence-defined oligomers via a unique approach, combining the Passerini three-component reaction (P 3CR) and a Diels-Alder reaction based on photo-caged dienes. Based on a Passerini linker unit carrying an isocyano group for chain extension via P 3CR and a maleimide moiety for photo-enol conjugation enabling a modular approach for chain extension. Monodisperse oligomers are accessible in a stepwise fashion by switching between both reaction types...
January 16, 2018: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29336549/top-down-hydrogen-deuterium-exchange-analysis-of-protein-structures-using-ultraviolet-photodissociation-uvpd
#16
Nicholas I Brodie, Romain Huguet, Terry Zhang, Rosa Viner, Vlad Zabrouskov, Jingxi Pan, Evgeniy V Petrotchenko, Christoph H Borchers
Top-down hydrogen-deuterium exchange (HDX) analysis using electron capture or transfer dissociation Fourier transform mass spectrometry is a powerful method for the analysis of secondary structure of proteins in solution. The resolution of the method is a function of the extensive fragmentation of backbone bonds in the proteins. While fragmentation is usually extensive near the N- and C-termini, electron capture (ECD) or electron transfer dissociation (ETD) fragmentation methods sometimes lack good coverage of certain regions of the protein - most often in the middle of the sequence...
January 16, 2018: Analytical Chemistry
https://www.readbyqxmd.com/read/29336509/the-investigation-of-substituent-effects-on-the-fragmentation-pathways-of-pentacoordinated-phenoxyspirophosphoranes-by-esi-msn
#17
Xiaoyan Cui, Can Sun, Pei Zhao, Yanyan Wang, Yanchun Guo, Yufen Zhao, Shuxia Cao
The fragmentation pathways of pentacoordinated phenoxyspirophosphoranes were investigated in the positive mode by electrospray ionization multistage mass spectrometry (ESI-MSn ). The results demonstrate that the sodium adducts of the title compounds undergo two competitive fragmentation pathways, and the fragmentation patterns are heavily dependent on the various substituent patterns at the phenolic group. An electron-withdrawing substituent at the ortho-position always results in the removal of a corresponding phenol analogue, while cleavage by spiroring opening becomes the predominant fragmentation pathway if an electron-donating substituent is at the phenolic group...
January 16, 2018: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/29336171/phenolic-composition-antioxidant-and-antinociceptive-activities-of-syringa-vulgaris-l-bark-and-leaf-extracts
#18
Erzsébet Varga, Csenge Barabás, Anita Tóth, Imre Boldizsár, Béla Noszál, Gergő Tóth
Metabolite profile, antioxidant and antinociceptive activities of Syringa vulgaris bark and leaf methanolic extracts were investigated. By means of HPLC-DAD-ESI-TOF and HPLC-DAD-ESI-MS/MS, a total of 33 phenolics were identified, including 15 secoiridoids, 6 phenylpropanoids, 3 flavonoids, 3 lignans and 6 low molecular weight phenols. Validated quantitative analysis show that syringin (2.52%) and rutin (1.13%) are the main phenolic compounds in bark and leaf, respectively. Notable radical scavenging and antinociceptive activities of the bark and leaf extracts were confirmed by in vitro DPPH● and ABTS●+ assays and by in vivo hot-plate method in mice, respectively...
January 16, 2018: Natural Product Research
https://www.readbyqxmd.com/read/29335793/accuracy-of-emergency-department-triage-using-the-emergency-severity-index-and-independent-predictors-of-under-triage-and-over-triage-in-brazil-a-retrospective-cohort-analysis
#19
Jeremiah S Hinson, Diego A Martinez, Paulo S K Schmitz, Matthew Toerper, Danieli Radu, James Scheulen, Sarah A Stewart de Ramirez, Scott Levin
BACKGROUND: Emergency department (ED) triage is performed to prioritize care for patients with critical and time-sensitive illness. Triage errors create opportunity for increased morbidity and mortality. Here, we sought to measure the frequency of under- and over-triage of patients by nurses using the Emergency Severity Index (ESI) in Brazil and to identify factors independently associated with each. METHODS: This was a single-center retrospective cohort study. The accuracy of initial ESI score assignment was determined by comparison with a score entered at the close of each ED encounter by treating physicians with full knowledge of actual resource utilization, disposition, and acute outcomes...
January 15, 2018: International Journal of Emergency Medicine
https://www.readbyqxmd.com/read/29335217/synthesis-and-characterisation-of-calix-4-arene-based-bis-triazole-bis-hexahydroquinoline-probing-highly-selective-fluorescence-quenching-towards-mercury-hg2-analyte
#20
Burhan Khan, Abdul Hameed, Aaliya Minhaz, Muhammad Raza Shah
In the present study, we are reporting the synthesis of a triazoles incorporated fluorescent hexahydroquinoline appended calix[4]arene 7 and its highly selective optical recognition ability towards Hg2+. The optical sensor 7 was synthesized via two different synthetic pathways and unambiguously characterized by mass spectrometry and NMR spectroscopy. The stoichiometric ratio between 7 and Hg2+ was determined as 1:1 based on Job's plot and ESI-MS analysis. The chemosensor 7 selectively recognized Hg2+ in the presence of competitive cations such as Cu2+, Cu1+, Co3+, Ni2+, Ag1+, Fe2+, Fe3+, Cr3+, Pb2+, Cd2+, Zn2+, Sn2+, Ti4+, Sb3+, In3+, Ba2+, Ca2+, and K1+...
January 10, 2018: Journal of Hazardous Materials
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