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https://www.readbyqxmd.com/read/29345972/trypsin-inhibitors-from-cajanus-cajan-and-phaseolus-limensis-possess-antioxidant-anti-inflammatory-and-antibacterial-activity
#1
Tooba Naz Shamsi, Romana Parveen, Sumbul Afreen, Mudasser Azam, Priyankar Sen, Yamini Sharma, Qazi Mohd Rizwanul Haque, Tasneem Fatma, Nikhat Manzoor, Sadaf Fatima
Protease inhibitors are one of the most promising and investigated subjects for their role in pharmacognostic and pharmacological studies. This study aimed to investigate antioxidant, anti-inflammatory, and antimicrobial activities of trypsin inhibitors (TIs) from two plant sources (Cajanus cajan and Phaseolus limensis). TI was purified from C. cajan (PUSA-992) by ammonium sulfate precipitation followed by ion exchange chromatography. TI from Phaseolus limensis (lima bean trypsin inhibitor; LBTI) was procured from Sigma-Aldrich, St...
January 18, 2018: Journal of Dietary Supplements
https://www.readbyqxmd.com/read/29342075/enrichment-and-identification-of-the-most-abundant-zinc-binding-proteins-in-developing-barley-grains-by-zinc-imac-capture-and-nano-lc-ms-ms
#2
Giuseppe Dionisio, Mohammad Nasir Uddin, Eva Vincze
Background: Zinc accumulates in the embryo, aleurone, and subaleurone layers at different amounts in cereal grains. Our hypothesis is that zinc could be stored bound, not only to low MW metabolites/proteins, but also to high MW proteins as well. Methods: In order to identify the most abundant zinc binding proteins in different grain tissues, we microdissected barley grains into (1) seed coats; (2) aleurone/subaleurone; (3) embryo; and (4) endosperm. Initial screening for putative zinc binding proteins from the different tissue types was performed by fractionating proteins according to solubility (Osborne fractionation), and resolving those via Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) followed by polyvinylidene fluoride (PVDF) membrane blotting and dithizone staining...
January 17, 2018: Proteomes
https://www.readbyqxmd.com/read/29341842/purification-characterization-of-fibrinolytic-protease-from-bacillus-amyloliquefaciens-mcc2606-and-analysis-of-fibrin-degradation-product-by-ms-ms
#3
Yogesh Devaraj, Savita Kumari Rajender, Prakash Motiram Halami
A serine protease with preference for fibrin protein was purified and characterized from B.amyloliquefaciens MCC2606, isolated from dosa batter. The protease was purified using ammonium sulphate precipitation, ion-exchange and gel filtration chromatography. The degradation activity of the protease towards the fibrin was significantly higher compared with other protein substrates in the study. The molecular weight of the CFR15-protease was estimated to be 32 kDa based on SDS-PAGE. The purified enzyme exhibited both fibrinolytic and fibrinogenolytic activity...
January 17, 2018: Preparative Biochemistry & Biotechnology
https://www.readbyqxmd.com/read/29341601/determining-double-bond-position-in-lipids-using-online-ozonolysis-coupled-to-liquid-chromatography-and-ion-mobility-mass-spectrometry
#4
Rachel A Harris, Jody C May, Craig A Stinson, Yu Xia, John A McLean
The increasing focus on lipid metabolism has revealed a need for analytical techniques capable of structurally characterizing lipids with a high degree of specificity. Lipids can exist as any one of a large number of double bond positional isomers, which are indistinguishable by single-stage mass spectrometry alone. Ozonolysis reactions coupled to mass spectrometry have previously been demonstrated as a means for localizing double bonds in unsaturated lipids. Here we describe an online, solution-phase reactor using ozone produced via a low-pressure mercury lamp, which generates aldehyde products diagnostic of cleavage at a particular double bond position...
January 17, 2018: Analytical Chemistry
https://www.readbyqxmd.com/read/29334125/determination-of-isoorientin-levels-in-rat-plasma-after-oral-administration-of-vaccinum-bracteatum-thunb-methanol-extract-by-high-performance-liquid-chromatography-tandem-mass-spectrometry
#5
Min-Ji Kim, Seung-Hwan Kwon, Choon-Gon Jang, Han-Joo Maeng
A simple, sensitive and rapid liquid chromatography tandem mass spectrometry method (LC-MS/MS) was developed and validated for the determination of plasma isoorientin levels in rats. After simple protein precipitation using methanol, chromatographic analysis was performed using a Synergi 4μ polar-RP 80A column (150 mm × 2.0 mm, 4 μm) under isocratic conditions and a mobile phase consisting of 0.1% formic acid in water and methanol (80:20, v/v) at a flow rate of 0.2 mL/min. In positive electrospray ionization mode, the protonated precursor and product ion transitions of isoorientin (m/z 449...
January 15, 2018: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/29332825/development-of-gd3-immobilized-glutathione-coated-magnetic-nanoparticles-for-highly-selective-enrichment-of-phosphopeptides
#6
Dandan Jiang, Xiqian Li, Jiutong Ma, Qiong Jia
In this study, we designed a gadolinium-based immobilized metal ion affinity chromatography material for the selective enrichment of phosphopeptides. Gadolinium ion was immobilized on the surface of glutathione-coated magnetic nanoparticles through a facile and effective synthetic route. The adsorbent integrated the advantages of superparamagnetism of Fe3O4 core, good biological compatibility of glutathione, and strong interaction between gadolinium ion and phosphopeptides. It was employed to enrich phosphopeptides from standard protein digests coupled with MALDI-TOF MS...
April 1, 2018: Talanta
https://www.readbyqxmd.com/read/29332797/electrodialytic-in-line-preconcentration-for-ionic-solute-analysis
#7
Shin-Ichi Ohira, Takayuki Yamasaki, Takumi Koda, Yuko Kodama, Kei Toda
Preconcentration is an effective way to improve analytical sensitivity. Many types of methods are used for enrichment of ionic solute analytes. However, current methods are batchwise and include procedures such as trapping and elution. In this manuscript, we propose in-line electrodialytic enrichment of ionic solutes. The method can enrich ionic solutes within seconds by quantitative transfer of analytes from the sample solution to the acceptor solution under an electric field. Because of quantitative ion transfer, the enrichment factor (the ratio of the concentration in the sample and to that in the obtained acceptor solution) only depends on the flow rate ratio of the sample solution to the acceptor solution...
April 1, 2018: Talanta
https://www.readbyqxmd.com/read/29331148/isolation-of-anti-extra-cellular-vesicle-single-domain-antibodies-by-direct-panning-on-vesicle-enriched-fractions
#8
Milica Popovic, Elisa Mazzega, Barbara Toffoletto, Ario de Marco
BACKGROUND: The thorough understanding of the physiological and pathological processes mediated by extracellular vesicles (EVs) is challenged by purification methods which are cumbersome, not reproducible, or insufficient to yield homogeneous material. Chromatography based on both ion-exchange and immune-capture can represent an effective method to improve EV purification and successive analysis. METHODS: Cell culture supernatant was used as a model sample for assessing the capacity of anion-exchange chromatography to separate distinct EV fractions and to isolate nanobodies by direct panning on whole EVs to recover binders specific for the native conformation of EV-surface epitopes and suitable to develop EV immune-capture reagents...
January 13, 2018: Microbial Cell Factories
https://www.readbyqxmd.com/read/29331063/simultaneous-pharmacokinetics-and-stability-studies-of-physalins-in-rat-plasma-and-intestinal-bacteria-culture-media-using-liquid-chromatography-with-mass-spectrometry
#9
Yunliang Zheng, Meihua Lin, Xingjiang Hu, You Zhai, Qiao Zhang, Yan Lou, Jianzhong ShenTu, Lihua Wu
Physalins are the major steroidal constituent of Physalis plants and display a range of biological activity. For this study, a rapid and sensitive high-performance liquid chromatography with triple quadrupole mass spectrometry method was developed for the simultaneous quantification of six physalins. Specifically, it was for the quantification of physalin A, physalin B, physalin D, physalin G, 4,7-didehydroneophysalin B and isophysalin B in rat plasma and rat intestinal bacteria. After a solid-phase extraction, analytes and internal standards (prednisolone) were separated on a Shield reverse-phase C18 column (measuring 3 mm × 150 mm with an internal diameter of 3...
January 13, 2018: Journal of Separation Science
https://www.readbyqxmd.com/read/29329709/characterization-of-singly-and-multiply-pegylated-insulin-isomers-by-reversed-phase-ultra-performance-liquid-chromatography-interfaced-with-ion-mobility-mass-spectrometry
#10
Selim Gerislioglu, Scott R Adams, Chrys Wesdemiotis
Conjugation of poly(ethylene glycol) (PEG) to protein drugs (PEGylation) is increasingly utilized in the biotherapeutics field because it improves significantly the drugs' circulatory half-life, solubility, and shelf-life. The activity of a PEGylated drug depends on the number, size, and location of the attached PEG chain(s). This study introduces a 2D separation approach, including reversed-phase ultra-performance liquid chromatography (RP-UPLC) and ion mobility mass spectrometry (IM-MS), in order to determine the structural properties of the conjugates, as demonstrated for a PEGylated insulin sample that was prepared by random amine PEGylation...
April 3, 2018: Analytica Chimica Acta
https://www.readbyqxmd.com/read/29329091/determination-of-imm-h004-and-its-active-glucuronide-metabolite-in-rat-plasma-and-ringer-s-solution-by-ultra-performance-liquid-chromatography-tandem-mass-spectrometry
#11
Jianwei Jiang, Ziqian Zhang, Xiaowen Zou, Rui Wang, Jie Bai, Shengyu Zhao, Xiaoqing Fan, Li Sheng, Yan Li
IMM-H004 is a novel neuroprotective agent and its glucuronide metabolite IMM-H004G has similar protective effects against cerebral ischemic injury in vivo and in vitro. A specific and sensitive ultra-performance liquid chromatography-tandem mass spectrometry method was established and validated for determination of IMM-H004 and IMM-H004G simultaneously in rat plasma and Ringer's solution. Plasma samples containing IMM-H004, IMM-H004G and internal standard propranolol were prepared by direct protein precipitation in a sample-to-solvent ratio of 1:2:6 (plasma: water: acetonitrile), whereas no protein precipitation was required for Ringer's solution samples...
December 29, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29328967/mycotoxin-production-of-alternaria-strains-isolated-from-korean-barley-grains-determined-by-lc-ms-ms
#12
Thuong T T Nguyen, Jueun Kim, Sun Jeong Jeon, Chul Won Lee, Naresh Magan, Hyang Burm Lee
Twenty-four Alternaria strains were isolated from barley grain samples. These strains were screened for the production of mycotoxins on rice medium using thin layer chromatography. All 24 strains produced at least one of the five mycotoxins (ALT, AOH, ATX-I, AME, and TeA). Three representative strains, namely EML-BLDF1-4, EML-BLDF1-14, and EML-BLDF1-18, were further analyzed using a new LC-MS/MS-based mycotoxin quantification method. This method was used to detect and quantify Alternaria mycotoxins. We used positive ion electrospray mass spectrometry with multiple reaction mode (MRM) for the simultaneous quantification of various Alternaria mycotoxins produced by these strains...
January 3, 2018: International Journal of Food Microbiology
https://www.readbyqxmd.com/read/29325877/dmcatd-a-cathepsin-d-like-peptidase-of-the-hematophagous-insect-dipetalogaster-maxima-hemiptera-reduviidae-purification-bioinformatic-analyses-and-the-significance-of-its-interaction-with-lipophorin-in-the-internalization-by-developing-oocytes
#13
Jimena Leyria, Leonardo L Fruttero, Rodrigo Ligabue-Braun, Marina S Defferrari, Estela L Arrese, José L Soulages, Beatriz P Settembrini, Celia R Carlini, Lilián E Canavoso
DmCatD, a cathepsin D-like peptidase of the hematophagous insect Dipetalogaster maxima, is synthesized by the fat body and the ovary and functions as yolk protein precursor. Functionally, DmCatD is involved in vitellin proteolysis. In this work, we purified and sequenced DmCatD, performed bioinformatic analyses and investigated the events involved in its targeting and storage in developing oocytes. By ion exchange and gel filtration chromatography, DmCatD was purified from egg homogenates and its identity was confirmed by mass spectrometry...
January 8, 2018: Journal of Insect Physiology
https://www.readbyqxmd.com/read/29324281/chemical-profiling-of-euphorbia-fischeriana-steud-by-uhplc-q-tof-ms
#14
Canjian Wang, Xiaoqi Zhang, Xiaohong Yan, Wencai Ye, Shuangcheng Ma, Yingqiao Jiang
Ultra-high-performance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry (UHPLC-Q/TOF-MS) in positive ion mode was used to profile and identify the major constituents in Euphorbia fischeriana Steud. (E. fischeriana). An Agilent ZORBAX SB-C18 column was used to separate the crude extract of E. fischeriana, and the mobile phases were acetonitrile and 0.1% aqueous formic acid (v/v). A total of 40 peaks were detected, and 37 components, including phloroglucinol derivatives, diterpenoids and nitrogenous compounds, were identified based on their accurate masses and fragmentation characteristics...
December 26, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29324081/determination-of-endogenous-concentrations-of-nitrites-and-nitrates-in-different-types-of-cheese-in-the-united-states-method-development-and-validation-using-ion-chromatography
#15
Susan Genualdi, Nahyun Jeong, Lowri DeJager
Nitrites and nitrates can be present in dairy products from both endogenous and exogenous sources. In the European Union (EU), 150 mg kg-1 of nitrates are allowed to be added to the cheese milk during the manufacturing process. The CODEX General Standard for Food Additives (GSFA) has a maximum permitted level of 50 mg kg-1 residue in cheese, while in the United States (US) nitrates are un-approved for use as food additives in cheese. In order to be able to investigate imported cheeses for nitrates intentionally added as preservatives and the endogenous concentrations of nitrates and nitrites present in cheeses in the US marketplace, a method was developed and validated using ion chromatography with conductivity detection...
January 11, 2018: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/29323783/chiral-ligand-exchange-countercurrent-chromatography-enantioseparation-of-amino-acids
#16
Qing Xiong, Jing Jin, Liqiong Lv, Zhisi Bu, Shengqiang Tong
This work deals with the enantioseparation of α-amino acids by chiral ligand exchange high-speed countercurrent chromatography using N-n-dodecyl-l-hydroxyproline as a chiral ligand and copper(II) as a transition metal ion. A biphasic solvent system composed of n-hexane/n-butanol/aqueous phase with different volume ratios was selected for each α-amino acid. The enantioseparation conditions were optimized by enantioselective liquid-liquid extractions, in which the main influence factors, including type of chiral ligand, concentration of chiral ligand and transition metal ion, separation temperature and pH of aqueous phase, were investigated for racemic phenylalanine...
January 11, 2018: Journal of Separation Science
https://www.readbyqxmd.com/read/29323367/quantitative-mass-spectrometry-imaging-of-glutathione-in-healthy-and-cancerous-hen-ovarian-tissue-sections-by-infrared-matrix-assisted-laser-desorption-electrospray-ionization-ir-maldesi
#17
Milad Nazari, Mark T Bokhart, Philip L Loziuk, David C Muddiman
A quantitative mass spectrometry imaging (QMSI) method for absolute quantification of glutathione (GSH) in healthy and cancerous hen ovarian tissues using infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) is presented. Using this technique, the ion abundance of GSH was normalized to that of a structural analogue, which was sprayed on the slide prior to mounting the tissue sections. This normalization strategy significantly improved the voxel-to-voxel variability; the variability is attributed to the overall ionization process...
January 11, 2018: Analyst
https://www.readbyqxmd.com/read/29321022/serum-metabolic-profiling-identified-a-distinct-metabolic-signature-in-patients-with-idiopathic-pulmonary-fibrosis-a-potential-biomarker-role-for-lysopc
#18
Barbara Rindlisbacher, Cornelia Schmid, Thomas Geiser, Cédric Bovet, Manuela Funke-Chambour
BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a lethal lung disease of unknown etiology. Patients present loss of lung function, dyspnea and dry cough. Diagnosis requires compatible radiologic imaging and, in undetermined cases, invasive procedures such as bronchoscopy and surgical lung biopsy. The pathophysiological mechanisms of IPF are not completely understood. Lung injury with abnormal alveolar epithelial repair is thought to be a major cause for activation of profibrotic pathways in IPF...
January 10, 2018: Respiratory Research
https://www.readbyqxmd.com/read/29320724/purification-and-characterization-of-a-novel-high-molecular-weight-alkaline-protease-produced-by-an-endophytic-bacillus-halotolerans-strain-ct2
#19
Gharbi Dorra, Karkouch Ines, Ben Slimene Imen, Coquet Laurent, Azaiez Sana, Olfa Tabbene, Cosette Pascal, Jouenne Thierry, Limam Ferid
A protease-producing strain CT2 isolated from Tunisian potatoes, exhibiting a potent protease activity (prot CT2), was identified as Bacillus halotolerans according to 16S ribosomal DNA sequence analysis. Maximum prot CT2 production was obtained in medium supplemented with bean seed proteins. Proteolytic activity was purified by ammonium sulphate precipitation, Sephacryl S-200 gel filtration and SP-sepharose cation-exchange chromatography. Optimal enzyme activity was reached at pH 9 and temperature of 50 °C...
January 7, 2018: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/29320174/comprehensive-analysis-of-changes-in-crude-oil-chemical-composition-during-biosouring-and-treatments
#20
Jeremy A Nowak, Pravin Malla Shrestha, Robert Jay Weber, Amy M McKenna, Huan Chen, John D Coates, Allen H Goldstein
Biosouring in crude oil reservoirs by sulfate-reducing microbial communities (SRCs) results in hydrogen sulfide production, precipitation of metal sulfide complexes, increased industrial costs of petroleum production, and exposure issues for personnel. Potential treatment strategies include nitrate or perchlorate injections into reservoirs. Gas chromatography with vacuum ultraviolet ionization and high-resolution time-of-flight mass spectrometry (GC-VUV-HTOF) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) combined with electrospray ionization were applied in this study to identify hydrocarbon degradation patterns and product formations in crude oil samples from biosoured, nitrate treated, and perchlorate treated bioreactor column experiments...
January 10, 2018: Environmental Science & Technology
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