996 resultados para Isolated carbonate platforms


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The new dibromotyrosine derivative 3,5-dibromo-4-[3'dimethylamonium]propoxyphenyl]-N,N,N-trimethylethanamonium, here referred to as aplysfistularine (1), was isolated from the marine sponge Aplysina fistularis along with 2-(3,5-dibromo-4methoxyphenyl)-N,N,N-trimethylethanamonium (2), aplysterol (3) and 24,28-didehydroaplysterol (4). Their identification was performed by mass spectrometry, infrared, ¹H and 13C NMR, and by comparison with literature data. Compound 2 and the mixture of 3 and 4 were tested in vitro (inhibitory activity) with supercoiled DNA relaxation techniques, and showed inhibitory activity on human DNA topoisomerase II-α. Compound 1 was not tested due to paucity of the material.

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A new triterpene, 1-epi-castanopsol, besides eleven known compounds: sitosterol, stigmasterol, campesterol, lupeol, lupenone, simirane B, syringaresinol, scopoletin, isofraxidin, 6,7,8-trimethoxycoumarin and harman, were isolated from the wood of Simira glaziovii. The structures of the known compounds were defined by 1D, 2D ¹H, 13C NMR spectra data analyses and comparison with literature data. The detailed spectral data analyses allowed the definition of the structure of the new 1-epi isomer of castanopsol and performance of ¹H and 13C NMR chemical shift assignments.

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MeOH extract from the leaves of Plectranthus barbatus Andrews (Lamiaceae), showed in vitro anti-trypanosomal activity. The bioassay-guided fractionation resulted in the isolation of a gallic acid derivative, identified as 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), after thorough NMR and MS spectral analysis. Finally, this compound was tested against trypomastigote forms of T. cruzi and displayed an EC50 value of 67 µM, at least 6.6-fold more effective than the standard drug benznidazole. This is the first occurrence of PGG in the Plectranthus genus and the first anti-parasitic activity described for PGG in the literature.

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Interaction and physicochemical characterization of dispersions of naproxen in calcium carbonate after freeze-drying the wet-state equilibrated mixture have been investigated by analytical methods. The FT-IR study revealed the acid-base reaction between naproxen and calcium carbonate. The DSC study indicated physical interaction and significantly diminished crystallinity of naproxen in the formulation containing higher quantities of calcium carbonate. Furthermore, the SEM study showed the reduced particle size and loss of crystalline morphology in the same sample. Drug release increased with the increase of calcium carbonate in the formulations. Formulation of naproxen with calcium carbonate in 1:2 ratio allowed its dissolution to the greatest extent (94.96%) while other compositions, 1:0.5 and 1:1, showed 80.86% and 78.30% release, respectively.

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Turnera subulata Sm., known as "Chanana" or "flor-do-Guarujá" in Brazilian folklore, is a plant species belonging to the subfamily Turneroideae of family Passifloraceae, which is used for various medicinal purposes in Brazil. The phytochemical study conducted here led to the isolation and identification of ten compounds present in T. subulata: two mixtures of steroids, sitosterol and stigmasterol (nonglycosylated and glycosylated); a mixture of flavonoids, 5,7,4′-trihidroxiflavona-8-C-α-glucopyranoside and 5,7,3′,4′-tetrahidroxiflavona-8-C-α-glucopyranosidel; and four phaeophytins, phaeophytin purpurin-18-phytyl ester, a rare natural product, phaeophytin a , 13²-hydroxy-(13²-S)-phaeophytin a , and phaeophytin b Phaeophytin b exhibited electrochemical activity similar to that of phthalocyanines.

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The present study aimed to investigate the in vitro effects of isoschaftoside isolated from Syngonium podophyllum on pig kidney Na+,K+-ATPase. The Na+, K+-ATPase activity was determined by colorimetric measurement of inorganic phosphate (Pi), resulting from ATP hydrolysis. Isoschaftoside significantly decreased the renal Na+, K+-ATPase activity at the highest concentration as well as at a lower concentration. Our work suggests that isoschaftoside is a promising compound for the treatment of hypertension.

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In this paper, the chemical study of Hortia superba and antimycobacterial potential of Hortia species were investigated. Crude extracts and limonoids, alkaloids, dihydrocinnamic acid derivatives and coumarins isolated from Hortia superba, Hortia oreadica and Hortia brasiliana were evaluated against Mycobacterium tuberculosis H37Rv, Mycobacterium kansasii and Mycobacterium avium. The results obtained demonstrated an inhibitory effect of the dichloromethane extract of leaves of H. oreadica (MIC 31.25 µg mL-1), indolequinazoline (15.62 µg mL-1) and furoquinoline (31.25 µg mL-1) alkaloids, and dihydrocinnamic acid derivatives (62.50 µg mL-1), on the growth of M. tuberculosis. These results are promising in relation to the search for biologically active natural products and could be useful in the development of effective new drugs against mycobacteria.

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Electrosynthesis of dimethyl carbonate (DMC) from methanol and carbon monoxide using an Cu(phen)Cl2 catalyst was achieved at room temperature and atmospheric pressure. The catalytic activity of the ligand 1,10-phenanthroline (phen) and the catalytic system were analyzed. The IR characterization results for the complex catalyst showed that copper ions were coordinated by nitrogen atoms of phen. In addition, the effects of the influencing factors, such as reaction time (t), reaction temperature (T) and the surface area of the working electrode (SWE) were studied.

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Cytospora eucalypticola has been frequently associated with twig and stem cankers and as endophyte of Eucalyptus globulus and E. grandis in Uruguay. Mycelium discs of two C. eucalypticola isolates obtained from actively growing colonies were inoculated, both superficially and on experimentally wounded stems of E. globulus and E. grandis. No inoculated and control plants have shown any discoloration, gumosis or necrosis nor did they display lesions ten months after inoculation. Callus tissue was formed, partially or wholly occluding the wounds. The ability to penetrate healthy tissues and the inability to produce lesions evidenced that the presence of C. eucalypticola in twig and stem cankers could result from saprotrophic expansion of the endophytic mycelium in dying tissues, cankers probably being produced by different environmental stress conditions.

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Solid Ln-OHCO3-DMCP compounds, where Ln represents lanthanides (III) and yttrium (III) ions and DMCP is the anion 4-dimethylaminocinnamylidenepyruvate, have been prepared. Thermogravimetry, derivative thermogravimetry (TG, DTG), differential scanning calorimetry (DSC), x-Ray diffraction powder patterns and elemental analysis have been used to characterize the compounds. The thermal stability as well as the thermal decomposition of these compounds were studied using an alumina crucible in an air atmosphere.

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One filler often utilized in flexible polyurethane foams is calcium carbonate (CaCO3) because it is non-abrasiveness, non-toxicity and facilitated pigmentation. However, it is observed that the excess of commercial CaCO3 utilized in industry possibly causing permanent deformations and damaging the quality of the final product. The effect of different concentrations of commercial CaCO3, in flexible foams, was studied. Different concentrations of CaCO3 were used for the synthesis of flexible polyurethane foams, which were submitted to morphological and thermal analyses to verify the alterations provoked by the progressive introduction of this filler.

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The disparity found in the molecular structures of compounds isolated from nine plants of the Swartzia genus indicates that the Swartzia species that furnished cassane diterpenoids and triterpenoidal saponins are more recent, since these metabolites have adopted the mevalonic acid route of formation, abandoning the shikimic acid/acetate route that produces the isoflavonoids found in the remaining species. Chemical indexes calculated from the molecular structure diversities of sixteen 8,11,13-trien-abietane diterpenoids isolated from Swartzia langsdorffii and S. arborescens indicate that S. arborescens is more recent than S. langsdorffii. The results suggest a more evolved position in Swartzia species of the section Possira.

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Microorganisms for biological control are capable of producing active compounds that inhibit the development of phytopathogens, constituting a promising tool toob tain active principles that could replace synthetic pesticides. This study evaluatedtheability of severalpotentialbiocontrol microorganismsto produce active extracellular metabolites. In vitro antagonistic capability of 50 bacterial isolates from rhizospheric soils of "criolla" potato (Solanum phureja) was tested through dual culture in this plant with different plant pathogenic fungi and bacteria. Isolates that showed significantly higher antagonistic activity were fermented in liquid media and crude extracts from the supernatants had their biological activities assessed by optical density techniques. Inhibitory effecton tested pathogens was observed for concentrations between 0.5% and 1% of crude extracts. There was a correlation between the antimicrobial activity of extracts and the use of nutrient-rich media in bacteria fermentation. Using a bioguided method, a peptidic compound, active against Fusarium oxysporum, was obtained from the 7ANT04 strain (Pyrobaculum sp.). Analysis by nuclear magnetic resonance and liquid chromatography coupled to mass detector evidenced an 11-amino acid compound. Bioinformatic software using raw mass data confirmed the presence of a cyclic peptide conformed by 11 mostly non-standard amino acids.

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Soybean target leaf spot, caused by the fungus Corynespora cassiicola, is controlled especially by leaf application of fungicides. In the last seasons, in the central-west region of Brazil, the disease chemical control efficiency has been low. This led to the hypothesis that the control failure could be due to the reduction or loss of the fungus sensitivity to fungicides. To clarify this fact, in vitro experiments were conducted to determine mycelial sensitivity of five C. cassiicola isolates to fungicides. Mycelial growth was assessed based on the growth of the mycelium on the culture medium, in Petri dishes. The medium potato-dextrose-agar was supplemented with the concentrations 0; 0.01; 0.1; 1; 10; 20 and 40 mg/L of the active ingredients carbendazim, cyproconazole, epoxiconazole, flutriafol and tebuconazole. The experiment was conducted and repeated twice in a controlled environment, temperature of 25±2ºC and photoperiod of 12 hours. Data on the percentage of mycelial inhibition were subjected to logarithmic regression analysis and the concentration that inhibits 50% of the mycelial growth (IC50) was calculated. Loss of sensitivity to carbendazim was observed for three fungal isolates, IC50 > 40 mg/L. Considering all five isolates, the IC50 for tebuconazole ranged from 1.89 to 2.80 mg/L, for epoxiconazol from 2.25 to 2.91, for cyproconazole from 9.21 to 20.32 mg/L, and for flutriafol from 0.77 to 2.18 mg/L. In the absence of information on the reference IC50 determined for wild isolates, the lowest values generated in our study can be used as standard to monitor the fungus sensitivity.

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In this report, we summarize results of our part of the ÄLYKOP-project on customer value creation in the intersection of the health care, ICT, forest and energy industries. The research directs to describe how industry transformation and convergence create new possibilities, business opportunities and even new industries.The report consists of findings which are presented former in academic publications. The publication discusses on customer value, service provision and resource basis of the novel concepts through multiple theorethical frameworks. The report is divided into three maim sections which are theoretical background, discussion on health care industry and evaluations regarding novel smart home concepts. Transaction cost economics and Resource- Based view on the firm provides the theoretical basis to analyze the prescribed phenomena. The health care industry analysis describes the most important changes in the demand conditions of health care services, and explores the features that are likely to open new business opportunities for a solution provider. The third part of the report on the smart home business provides illustrations few potential concepts that can be considered to provide solutions to economical problems which arise from aging of population. The results provide several recommendations for the smart home platform developers in public and private sectors. By the analysis, public organizations dominate service provision and private markets are emergent state at present. We argue that public-private partnerships are nececssary for creating key suppliers. Indeed, paying attion on appropriate regulation, service specifications and technology standards would foster diffusion of new services. The dynamics of the service provision networks is driven by need for new capabiltities which are required for adapting business concepts to new competitive situation. Finally, the smart home framework revealed links between conventionally distant business areas such as health care and energy distribution. The platform integrates functionalities different for purposes which however apply same resource basis.