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Ana Caroline Lustosa de Melo Carvalho Thiago de Sousa Fonseca Marcos Carlos de Mattos Maria da Concei??o Ferreira de Oliveira Telma Leda Gomes de Lemos Francesco Molinari Diego Romano Immacolata Serra 《International journal of molecular sciences》2015,16(12):29682-29716
Biocatalysis offers an alternative approach to conventional chemical processes for the production of single-isomer chiral drugs. Lipases are one of the most used enzymes in the synthesis of enantiomerically pure intermediates. The use of this type of enzyme is mainly due to the characteristics of their regio-, chemo- and enantioselectivity in the resolution process of racemates, without the use of cofactors. Moreover, this class of enzymes has generally excellent stability in the presence of organic solvents, facilitating the solubility of the organic substrate to be modified. Further improvements and new applications have been achieved in the syntheses of biologically active compounds catalyzed by lipases. This review critically reports and discusses examples from recent literature (2007 to mid-2015), concerning the synthesis of enantiomerically pure active pharmaceutical ingredients (APIs) and their intermediates in which the key step involves the action of a lipase. 相似文献
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Daniela F. S. Fonseca ?ngelo C. Salvador Sónia A. O. Santos Carla Vilela Carmen S. R. Freire Armando J. D. Silvestre Sílvia M. Rocha 《International journal of molecular sciences》2015,16(6):14194-14209
The lipophilic composition of wild Arbutus unedo L. berries, collected from six locations in Penacova (center of Portugal), as well as some general chemical parameters, namely total soluble solids, pH, titratable acidity, total phenolic content and antioxidant activity was studied in detail to better understand its potential as a source of bioactive compounds. The chemical composition of the lipophilic extracts, focused on the fatty acids, triterpenoids, sterols, long chain aliphatic alcohols and tocopherols, was investigated by gas chromatography–mass spectrometry (GC–MS) analysis of the dichloromethane extracts. The lipophilic extractives of the ripe A. unedo berries ranged from 0.72% to 1.66% (w/w of dry weight), and consisted mainly of triterpenoids, fatty acids and sterols. Minor amounts of long chain aliphatic alcohols and tocopherols were also identified. Forty-one compounds were identified and among these, ursolic acid, lupeol, α-amyrin, linoleic and α-linolenic acids, and β-sitosterol were highlighted as the major components. To the best of our knowledge the current research study provides the most detailed phytochemical repository for the lipophilic composition of A. unedo, and offers valuable information for future valuation and exploitation of these berries. 相似文献
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Adriano do Nascimento Simões Samara Lopes de Almeida Cristine Vanz Borges Kelem Silva Fonseca Aurélio Paes Barros Júnior José Ricardo Tavares de Albuquerque Camila Renata Corrêa Igor Otavio Minatel Maria Aparecida dos Santos Morais Marla Silvia Diamante Giuseppina Pace Pereira Lima 《Journal of Food Biochemistry》2020,44(8):e13322
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This work presents the development of two different finite piping elbow elements with two nodal tubular sections for mechanical analysis. The formulation is based on thin shell displacement theory, where the displacement is based on high-order polynomial or trigonometric functions for rigid-beam displacement, and uses Fourier series to model warping and ovalization phenomena of cross-tubular section. To model the internal pressure effect an additional formulation is used in the elementary stiffness matrix definition. Elbows attached to nozzle or straight pipes produce a stiffening effect due to the restraint of ovalization provided by the adjacent components. When submitted to any efforts, the excessive oval shape may reduce the structural resistance and can lead to structural collapse. For design tubular systems it is also important to consider the internal-pressure effect, given its effect on the reduction of the pipe flexibility. Some conclusions and examples are compared with results produced by other authors. 相似文献
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Total lead and its stable isotopes were analysed in sediment cores, leaves, stem and roots of Sacorconia fruticosa and Spartina maritima sampled from Tagus (contaminated site) and Guadiana (low anthropogenic pressure) salt marshes. Lead concentration in vegetated sediments from the Tagus marsh largely exceeded the levels in non-vegetated sediments. Depth profiles of (206)Pb/(207)Pb and (206)Pb/(208)Pb showed a decrease towards the surface ((206)Pb/(207)Pb=1.160-1.167) as a result of a higher proportion of pollutant Pb components. In contrast, sediments from Guadiana marsh exhibited low Pb concentrations and an uniform isotopic signature ((206)Pb/(207)Pb=1.172+/-0.003) with depth. This suggests a homogeneous mixing of mine-derived particles and pre-industrial sediments with minor inputs of anthropogenic Pb. Lead concentrations in roots of plants from the two marshes were higher than in leaves and stems, indicating limited transfer of Pb to aerial parts. A similar Pb isotopic signature was found in roots and in vegetated sediments, indicating that Pb uptake by plants reflects the input in sediments as determined by a significant anthropogenic contribution of Pb at Tagus and by mineralogical Pb phases at Guadiana. The accumulation in roots from Tagus marsh (max. 2870 microg g(-1) in S. fruticosa and max. 1755 microg g(-1) in S. maritima) clearly points to the dominant role of belowground biomass in the cycling of anthropogenic Pb. The fraction of anthropogenic Pb in belowground biomass was estimated based on the signature of anthropogenic Pb components in sediments ((206)Pb/(207)Pb=1.154). Since no differences exist between Pb signature in roots and upper sediments, the background and anthropogenic levels of Pb in roots were estimated. Interestingly, both background and anthropogenic Pb in roots exhibited a maximum at the same depth, although the proportion of anthropogenic Pb was relatively constant with depth (83+/-4% for S. fruticosa and 74+/-8% for S. maritima). 相似文献
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Tânia F.C.V. Silva M. Elisabete F. Silva A. Cristina Cunha-Queda Amélia Fonseca Isabel Saraiva M.A. Sousa C. Gonçalves M.F. Alpendurada Rui A.R. Boaventura Vítor J.P. Vilar 《Water research》2013
A multistage treatment system, at a scale close to the industrial, was designed for the treatment of a mature raw landfill leachate, including: a) an activated sludge biological oxidation (ASBO), under aerobic and anoxic conditions; b) a solar photo-Fenton process, enhancing the bio-treated leachate biodegradability, with and without sludge removal after acidification; and c) a final polishing step, with further ASBO. 相似文献