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Isolation and characterization of compounds

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https://www.readbyqxmd.com/read/28431313/raman-spectroscopy-for-the-characterization-of-different-fractions-of-hemp-essential-oil-extracted-at-130%C3%A2-c-using-steam-distillation-method
#1
Muhammad Asif Hanif, Haq Nawaz, Saima Naz, Rubina Mukhtar, Nosheen Rashid, Ijaz Ahmad Bhatti, Muhammad Saleem
In this study, Raman spectroscopy along with Principal Component Analysis (PCA) is used for the characterization of pure essential oil (pure EO) isolated from the leaves of the Hemp (Cannabis sativa L.,) as well as its different fractions obtained by fractional distillation process. Raman spectra of pure Hemp essential oil and its different fractions show characteristic key bands of main volatile terpenes and terpenoids, which significantly differentiate them from each other. These bands provide information about the chemical composition of sample under investigation and hence can be used as Raman spectral markers for the qualitative monitoring of the pure EO and different fractions containing different active compounds...
April 1, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28427461/inhibitory-activities-of-selected-sudanese-medicinal-plants-on-porphyromonas-gingivalis-and-matrix-metalloproteinase-9-and-isolation-of-bioactive-compounds-from-combretum-hartmannianum-schweinf-bark
#2
Ebtihal Abdalla M Mohieldin, Ali Mahmoud Muddathir, Tohru Mitsunaga
BACKGROUND: Periodontal diseases are one of the major health problems and among the most important preventable global infectious diseases. Porphyromonas gingivalis is an anaerobic Gram-negative bacterium which has been strongly implicated in the etiology of periodontitis. Additionally, matrix metalloproteinases-9 (MMP-9) is an important factor contributing to periodontal tissue destruction by a variety of mechanisms. The purpose of this study was to evaluate the selected Sudanese medicinal plants against P...
April 20, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28426249/non-enzymatic-electrochemistry-in-characterization-and-analysis-of-steroid-compounds
#3
Jan Klouda, Jiří Barek, Karel Nesměrák, Karolina Schwarzová-Pecková
This review summarizes achievements in electrochemistry-related research of steroid-based compounds in clinical, pharmaceutical, and environmental analysis. Special attention is paid to compounds possessing none or only isolated double bonds at the steroid core. Their direct redox activity is limited to far positive/negative potentials under variety of conditions and electrode materials and relies on the functional groups attached to the steroid skeleton, or as the case may be its double bond, or moieties present at the side chain...
April 20, 2017: Critical Reviews in Analytical Chemistry
https://www.readbyqxmd.com/read/28426213/role-of-mediator-and-effects-of-temperature-on-ortho-c-n-bond-fusion-reactions-of-aniline-using-ruthenium-templates-isolation-and-characterization-of-new-ruthenium-complexes-of-the-in-situ-generated-ligands
#4
Suman K Roy, Debabrata Sengupta, Santi Prasad Rath, Tanushri Saha, Subhas Samanta, Sreebrata Goswami
In this work, ortho-C-N bond fusion reactions of aniline are followed by the use of two different ruthenium mediators. Reaction of aniline with [Ru(III)(terpy)Cl3] (terpy = 2,2':6',2″-terpyridine) resulted in a trans bis-aniline ruthenium(II) complex [1](+) which upon oxidation with H2O2 produced compound [2](+) of a bidentate ligand, N-phenyl-1,2-benzoquinonediimine, due to an oxidative ortho-C-N bond fusion reaction. Complex [1](+) and aniline (neat) at 185 °C produced a bis-chelated ruthenium complex (3)...
April 20, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28424496/the-chemical-characterization-of-nigerian-propolis-samples-and-their-activity-against-trypanosoma-brucei
#5
Ruwida Omar, John O Igoli, Tong Zhang, Alexander I Gray, Godwin U Ebiloma, Carol J Clements, James Fearnley, RuAngeli Edrada Ebel, Tim Paget, Harry P de Koning, David G Watson
Profiling of extracts from twelve propolis samples collected from eight regions in Nigeria was carried out using high performance liquid chromatography (LC) coupled with evaporative light scattering (ELSD), ultraviolet detection (UV) and mass spectrometry (MS), gas chromatography mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). Principal component analysis (PCA) of the processed LC-MS data demonstrated the varying chemical composition of the samples. Most of the samples were active against Trypanosoma b...
April 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28422495/cochliotoxin-a-dihydropyranopyran-4-5-dione-and-its-analogues-produced-by-cochliobolus-australiensis-display-phytotoxic-activity-against-buffelgrass-cenchrus-ciliaris
#6
Marco Masi, Susan Meyer, Suzette Clement, Alessio Cimmino, Massimo Cristofaro, Antonio Evidente
Buffelgrass (Pennisetum ciliare or Cenchrus ciliaris) is a perennial grass that has become highly invasive in the Sonoran Desert of southern Arizona. In the search for novel control strategies against this weed, strains of the foliar fungal pathogen Cochliobolus australiensis from buffelgrass have been screened for their ability to produce phytotoxic metabolites that could potentially be used as natural herbicides in an integrated pest management strategy. A new phytotoxin, named cochliotoxin, was isolated from liquid culture of this fungus together with radicinin, radicinol, and their 3-epimers...
April 19, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28419281/expression-of-the-plasmodium-falciparum-clonally-variant-clag3-genes-in-human-infections
#7
Sofía Mira-Martínez, Evi van Schuppen, Alfred Amambua-Ngwa, Emmanuel Bottieau, Muna Affara, Marjan Van Esbroeck, Erika Vlieghe, Pieter Guetens, Núria Rovira-Graells, Gloria P Gómez-Pérez, Pedro L Alonso, Umberto D'Alessandro, Anna Rosanas-Urgell, Alfred Cortés
Background.: Many genes of the malaria parasite Plasmodium falciparum show clonally variant expression regulated at the epigenetic level. These genes participate in fundamental host-parasite interactions and contribute to adaptive processes. However, little is known about their expression patterns during human infections. A peculiar case of clonally variant genes are the 2 nearly identical clag3 genes, clag3.1 and clag3.2, which mediate nutrient uptake and are linked to resistance to some toxic compounds...
February 7, 2017: Journal of Infectious Diseases
https://www.readbyqxmd.com/read/28418441/an-integrated-anti-arrhythmic-target-network-of-a-chinese-medicine-compound-wenxin-keli-revealed-by-combined-machine-learning-and-molecular-pathway-analysis
#8
Taiyi Wang, Ming Lu, Qunqun Du, Xi Yao, Peng Zhang, Xiaonan Chen, Weiwei Xie, Zheng Li, Yuling Ma, Yan Zhu
Wenxin Keli (WK), a Chinese patent medicine, is known to be effective against cardiac arrhythmias and heart failure. Although a number of electrophysiological findings regarding its therapeutic effect have been reported, the active components and system-level characterizations of the component-target interactions of WK have yet to be elucidated. In the current study, we present the first report of a new protective effect of WK on suppressing anti-arrhythmic-agent-induced arrhythmias. In a model of isolated guinea pig hearts, rapid perfusion of quinidine altered the heart rate and prolonged the Q-T interval...
April 18, 2017: Molecular BioSystems
https://www.readbyqxmd.com/read/28416546/anti-influenza-activity-of-bacillus-subtilis-probiotic-strain
#9
Darya Starosila, Svetlana Rybalko, Ludmila Varbanetz, Naila Ivanskaya, Iryna Sorokulova
Among Bacillus bacteria, B. subtilis is the most productive species of antimicrobial compounds. In this study, we analyzed the activity of probiotic strain B. subtilis 3 against influenza virus. The antiviral effect of this strain has been demonstrated in vitro and in vivo New peptide P18 produced by probiotic strain was isolated, purified, chemically synthesized, and characterized. Cytotoxicity studies demonstrated no toxic effect of P18 on Madin-Darby canine kidney (MDCK) cells, even in the highest tested concentration (100 μg/mL)...
April 17, 2017: Antimicrobial Agents and Chemotherapy
https://www.readbyqxmd.com/read/28411469/primary-hepatocytes-from-arctic-char-salvelinus-alpinus-as-a-relevant-arctic-in-vitro-model-for-screening-contaminants-and-environmental-extracts
#10
Karina Petersen, Maria T Hultman, Knut Erik Tollefsen
Contaminants find their way to the Arctic through long-range atmospheric transport, transport via ocean currents, and through increased anthropogenic activity. Some of the typical pollutants reaching the Arctic (PAHs, PCBs) are known to induce cytochrome P450 1a (CYP1A) protein expression and ethoxyresorufin-O-deethylase (EROD) activity through the aryl hydrocarbon receptor (AhR). In addition, some endocrine disrupting chemicals (EDCs) such as estrogen mimics (xenoestrogens) have been documented in Arctic areas and they may interfere with natural sexual development and reproduction...
April 2, 2017: Aquatic Toxicology
https://www.readbyqxmd.com/read/28411365/analysis-of-glycosylated-flavonoids-extracted-from-sweet-cherry-stems-as-antibacterial-agents-against-pathogenic-escherichia-coli-isolates
#11
Alfredo Aires, Carla Dias, Rosa Carvalho, Maria José Saavedra
The aim of this study was to evaluate the bioactivity of flavonoids extracted from sweet-cherry stems which are often used by a traditional system of medicine to treat gastro-intestinal and urinary tract infections but lacking any consistent scientific evidence; moreover the information about the class of phenolics, their content and the potential bioactivity of such material is very scarce. Thus, in this context, we have set a research study in which we evaluated the profile and content of phenolics extracted from sweet-cherry stems through a conventional (70ºC and 20 min) and ultrasound assisted extraction (40 kHz, room temperature and 20 min)...
April 14, 2017: Acta Biochimica Polonica
https://www.readbyqxmd.com/read/28407977/structural-characterization-of-reaction-products-of-caftaric-acid-and-bisulfite-present-in-a-commercial-wine-using-high-resolution-mass-spectrometric-and-nuclear-magnetic-resonance-techniques
#12
Yoji Hayasaka, Cory A Black, Jeremy Hack, Paul Smith
Reaction products of bisulfite and caftaric acid were found in wines containing sulfites as a preservative. Acidic compounds were separated from wine and analyzed by HPLC combined with DAD and QTOF mass spectrometer. HPLC chromatograms of the expected [M-H](-) ion and UV absorption revealed the presence of five possible reaction products (a-e). These compounds were isolated then characterized by NMR and confirmed to be the reaction products as follows; 5-sulfo-(E)-caftaric acid (a), 2-sulfo-(Z)-caftaric acid (b), 2-sulfo-(E)-caftaric acid (c), (E)-caftaric acid-4-O-sulfate (d) and (E)-caftaric acid-3-O-sulfate (e)...
September 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28407417/the-elusive-palladium-diazo-adduct-captured-synthesis-isolation-and-structural-characterization-of-arnhc-pph2-pd-%C3%AF-2-n2c-ph-co2et
#13
Pedro J Pérez, Silvia G Rull, Eleuterio Álvarez, Manuel R Fructos, Tomás R Belderrain
The first example of a diazo compound adduct of palladium is reported. The complexes [(ArNHC-PPh2)M(η2-N2C(Ph)CO2Et)] (M = Ni, 3; M = Pd, 4; ArNHC-PPh2 = 3-(2,6-diisopropylphenyl)-1-[(diphenylphosphino)ethyl]imidazol-2-ylidene) have been prepared by ligand exchange with the styrene precursors [(ArNHC-PPh2)M(styrene)] (M = Ni, 1; M = Pd, 2). Complex 4 has been fully characterized, including X-ray analyses, in what constitutes the first example of a diazo compound adduct with this metal, closing the gap within groups 8 to 10 regarding this type of compounds...
April 13, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28406644/influence-of-the-steric-bulk-and-solvent-on-the-photoreactivity-of-ruthenium-polypyridyl-complexes-coordinated-to-l-proline
#14
Jordi-Amat Cuello-Garibo, Elena Pérez-Gallent, Lennard van der Boon, Maxime A Siegler, Sylvestre Bonnet
Ruthenium polypyridyl complexes are good candidates for photoactivated chemotherapy (PACT) provided that they are stable in the dark but efficiently photosubstitute one of their ligands. Here the use of the natural amino acid l-proline as a protecting ligand for ruthenium-based PACT compounds is investigated in the series of complexes Λ-[Ru(bpy)2(l-prol)]PF6 ([1a]PF6; bpy = 2,2'-bipyridine and l-prol = l-proline), Λ-[Ru(bpy)(dmbpy)(l-prol)]PF6 ([2a]PF6 and [2b]PF6; dmbpy = 6,6'-dimethyl-2,2'-bipyridine), and Λ-[Ru(dmbpy)2(l-prol)]PF6 ([3a]PF6)...
April 13, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28406288/tin-iv-compounds-with-2-c6f4pph2-substituents-and-their-reactivity-toward-palladium-0-formation-of-tin-palladium-complexes-via-oxidative-addition
#15
Erik Wächtler, Sven Wahlicht, Steven H Privér, Martin A Bennett, Birgit Gerke, Rainer Pöttgen, Erica Brendler, Robert Gericke, Jörg Wagler, Suresh K Bhargava
The tin(IV) compounds MexSn(2-C6F4PPh2)4-x (1, x = 1; 2, x = 2) and ClSn(2-C6F4PPh2)3 (3) were obtained from the reactions of 2-LiC6F4PPh2 with MeSnCl3 (3:1), Me2SnCl2 (2:1), or SnCl4 (3:1), respectively. The reactions of 2-LiC6F4PPh2 with SnCl4 in different stoichiometric ratios (4:1-1:1) gave 3 as the main product. Compound Cl2Sn(2-C6F4PPh2)2 (4) was formed in the transmetalation reaction of 3 and [AuCl(tht)] but could not be isolated. 1 and 2 react with palladium(0) sources {[Pd(PPh3)4] and [Pd(allyl)Cp]} by the oxidative addition of one of their Sn-CAryl bonds to palladium(0) with formation of the heterobimetallic complexes [MeSn(μ-2-C6F4PPh2)2Pd(κC-2-C6F4PPh2)] (5) and [Me2Sn(μ-2-C6F4PPh2)Pd(κ(2)-2-C6F4PPh2)] (6) featuring Sn-Pd bonds...
April 13, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28405774/bacillus-methylotrophicus-m4-96-isolated-from-maize-zea-mays-rhizoplane-increases-growth-and-auxin-content-in-arabidopsis-thaliana-via-emission-of-volatiles
#16
Paola Pérez-Flores, Eduardo Valencia-Cantero, Josué Altamirano-Hernández, Ramón Pelagio-Flores, José López-Bucio, Perla García-Juárez, Lourdes Macías-Rodríguez
Plant growth-promoting rhizobacteria stimulate plant growth and development via different mechanisms. In this study, we characterized the effect of volatiles from Bacillus methylotrophicus M4-96 isolated from the maize rhizosphere on root and shoot development, and auxin homeostasis in Arabidopsis thaliana. Phytostimulation occurred after 4 days of interaction between M4-96 and Arabidopsis grown on opposite sides of divided Petri plates, as revealed by enhanced primary root growth, root branching, leaf formation, and shoot biomass accumulation...
April 12, 2017: Protoplasma
https://www.readbyqxmd.com/read/28405241/design-and-synthesis-of-a-new-steroid-macrocyclic-derivative-with-biological-activity
#17
Maria López-Ramos, Lauro Figueroa-Valverde, Socorro Herrera-Meza, Marcela Rosas-Nexticapa, Francisco Díaz-Cedillo, Elodia García-Cervera, Eduardo Pool-Gómez, Regina Cahuich-Carrillo
The aims of this study were to evaluate the positive inotropic effect of a new macrocyclic derivative (compound 11) and characterize the molecular mechanism involved in its biological activity. The first step was achieved by synthesis of a macrocyclic derivative involving a series of reactions for the preparation of several steroid derivatives such as (a) steroid-pyrimidinone (3 and 4), (b) steroid-amino (5), (c) steroid-imino (6), (d) ester-steroid (7 and 8), and (e) amido-steroid (9 and 10). Finally, 11 was prepared by removing the tert-butyldimethylsilane fragment of 10...
April 2017: Journal of Chemical Biology
https://www.readbyqxmd.com/read/28403641/two-new-cytochalasan-derivatives-from-chaetomium-globosum-snshi-5-a-fungus-derived-from-extreme-environment
#18
Xiao-Yan Wang, Xia Yan, Mei-Juan Fang, Zhen Wu, Dong Wang, Ying-Kun Qiu
Two new cytochalasan derivatives, isochaetoglobosin Db (1) and cytoglobosin Ab (2), were isolated from an ethyl acetate extract of Chaetomium globosum SNSHI-5, a fungus derived from extreme environment. The structures of the new compounds were comprehensively characterized by HR-ESI-MS, (1)H NMR, (13)C NMR and 2D-NMR. Cytotoxic activity against H292 human lung cancer cell of the new compounds was tested. Isochaetoglobosin Db (1) showed potent cytotoxicity with IC50 of 3.5 μM, while cytoglobosin Ab was inactive (IC50 > 10 μM)...
April 12, 2017: Natural Product Research
https://www.readbyqxmd.com/read/28401469/bioactive-amento-flavone-isolated-from-cassia-fistula-l-leaves-exhibits-therapeutic-efficacy
#19
M Srividhya, H Hridya, V Shanthi, K Ramanathan
Novel natural compounds endowed with sound bioactivities are currently the utmost need as leads toward drug discovery. For the first time, here, we report the presence of Amentoflavone (biflavonoid) in the leaves of Cassia fistula L. Structural characterization was carried out using ultraviolet-visible spectrophotometer, Fourier transform infrared, nuclear magnetic resonance, and thin-layer chromatography. The isolated compound was further evaluated for its bioactivity. The compound demonstrated moderate cytotoxicity in liver carcinoma (HepG2) cells, and the comparative analysis for the standard and normal compound has also been validated...
May 2017: 3 Biotech
https://www.readbyqxmd.com/read/28401289/characterization-of-odorants-in-inflatable-aquatic-toys-and-swimming-learning-devices-which-substances-are-causative-for-the-characteristic-odor-and-potentially-harmful
#20
Christoph Wiedmer, Cristina Velasco-Schön, Andrea Buettner
Based on the observation of intense and offensive smells in the product group of aquatic toys, four representative products were exemplarily chosen and sensorially characterized by an expert panel. Panellists reported mostly almond- and rubber-like notes for three of the four samples, whereas the smell of the fourth sample was dominated by organic solvent-associated notes such as "nail polish-like." To elucidate the molecular reasons of these smells, we isolated the volatile fraction of the product by solvent extraction and high vacuum distillation, and identified the main odorants by aroma extract dilution analysis (AEDA), followed by one- and two-dimensional gas chromatography, with parallel mass spectrometric and olfactometric detection...
April 12, 2017: Analytical and Bioanalytical Chemistry
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