Polyhydroxybutyrate
Mostrando 25-36 de 51 artigos, teses e dissertações.
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25. Cloning and heterologous expression of genes responsible for synthesis of polyhydroxybutyrato em Bradyrhizobium elkanii / Clonagem e expressão heterologa dos genes responsaveis pela sintese de polihidroxibutirato em Bradyrhizobium elkanii
Polyhydroxyalkanoates (PHAs) are polymers of hydroxyalkanoate acids, produced and accumulated intracellularly as a source of carbon and energy storage material, in prokaryotic cells. Often, the PHAs accumulation occurs in conditions when the carbon source is in excess but one or several other nutrients are limited, and may represent up to 80% of the cell dry
Publicado em: 2009
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26. Effect of preparation conditions on morphology, drug content and release profiles of poly(hydroxybutyrate) microparticles containing piroxicam
No presente estudo foram preparadas micropartículas de poli(hidroxibutirato) contendo piroxicam pela técnica de emulsão-evaporação do solvente. A influência de alguns parâmetros do processo sobre a eficiência de encapsulação do fármaco foi avaliada por meio de um planejamento fatorial do tipo 2³. A eficiência de encapsulação do piroxicam vario
Journal of the Brazilian Chemical Society. Publicado em: 2008
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27. Compósitos de hidroxiapatita e polihidroxibutirato em defeitos ósseos experimentais na ulna de coelhos / Hydroxyapatite-polyhydroxybutyrate composites in experimentally made bone deffects in rabbits ulna
Biomaterials used today to treat bones defects and fractures still bear some deficiencies to be corrected. This study is a preliminary analysis of composites made of hydroxyapatite (HAP-91) and polyhydroxybutyrate (PHB) essentials characteristics to be used in orthopedics. The composites were studied in osseous defects concerning their biocompatibility, osse
Publicado em: 2007
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28. Characterization of poly-hydroxybutyrate-hydroxyvalerate (PHB-HV)/corn starch blend films / CaracterizaÃÃo de filmes de blenda de polihidroxibutirato-hidroxivalerato (PHB-HV)/amido de milho
Blendas de polihidroxibutirato-hidroxivalerato (PHB-HV) com amido de milho em diferentes concentraÃÃes foram preparadas pelo processo âcastingâ com clorofÃrmio. As propriedades mecÃnica, tÃrmica, morfolÃgica e fÃsico-quÃmica das blendas foram investigadas usando as anÃlises de textura, calorimetria diferencial de varredura, espectroscopia no infra
Publicado em: 2007
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29. In Vitro studies of bioactive glass/polyhydroxybutyrate composites
Bioactive materials can help bone reparation and regeneration by offering support to bone growth. In vitro studies of bioactive glass/polyhydroxybutyrate composites were carried out to evaluate the influence of the composition on the bioactivity through the presence of calcium phosphate (Ca-P) on the layer formed when the substrates were immerse in simulated
Materials Research. Publicado em: 2006-12
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30. Impregnation of pet films and PHB granules with curcumin in supercritical CO2
The process of dyeing poly(ethylene terephthalate) - PET films at 50, 60 and 65ºC and poly(hydroxybutyrate) - PHB granules at 60, 70 and 80ºC using supercritical carbon dioxide (scCO2) as solvent and ethanol as cosolvent was studied by DSC, TGA analysis and measurements of shrinkage to determine the morphological modifications caused by the scCO2 treatment
Brazilian Journal of Chemical Engineering. Publicado em: 2006-06
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31. Efeitos da radiaÃÃo Gama no polÃmero biodegradÃvel Poli(HIDROXIBUTIRATO) e no copolÃmero Poli(Hidroxibutirato-co-Hidroxivalerato)
Poly(hydroxybutyrate), PHB, is a biodegradable commercial polyester manufactured in Brazil and biosynthesized by Alcaligenes eutrophus bacteria from sugar cane biosynthesis. The great number of petrochemical plastics has brought about attention to biodegradable polymers. PHB is a thermoplastic with good properties and an excellent option as commodity. On the
Publicado em: 2006
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32. The effect of some processing conditions on the characteristics of biodegradable microspheres obtained by an emulsion solvent evaporation process
Unloaded microspheres were prepared from polyhydroxybutyrate (PHB) and polyhydroxybutyrate-co-valerate (PHB-HV) polymers using an oil-in-water emulsion solvent evaporation method. The study was conducted to evaluate how the polymer and some process parameters affect properties of the final microspheres such as particle size, superficial area, zeta potential,
Brazilian Journal of Chemical Engineering. Publicado em: 2004-01
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33. Putative structure and functions of a poly-beta-hydroxybutyrate/calcium polyphosphate channel in bacterial plasma membranes.
A poly-beta-hydroxybutyrate complex extracted from the plasma membranes of genetically competent Escherichia coli contained polyhydroxybutyrate:polyphosphate:calcium in molar ratios approximating 1:1:0.5. The chain length of the polyhydroxybutyrate was estimated as 120-200 subunits, and that of the polyphosphate was estimated as 130-170 subunits. The extract
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34. New Insight into the Role of the PhaP Phasin of Ralstonia eutropha in Promoting Synthesis of Polyhydroxybutyrate
Phasins are proteins that are proposed to play important roles in polyhydroxyalkanoate synthesis and granule formation. Here the phasin PhaP of Ralstonia eutropha has been analyzed with regard to its role in the synthesis of polyhydroxybutyrate (PHB). Purified recombinant PhaP, antibodies against PhaP, and an R. eutropha phaP deletion strain have been genera
American Society for Microbiology.
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35. Cloning and Characterization of the Polyhydroxybutyrate Depolymerase Gene of Pseudomonas stutzeri and Analysis of the Function of Substrate-Binding Domains
The extracellular polyhydroxybutyrate (PHB) depolymerase gene (phaZPst) of Pseudomonas stutzeri was cloned and sequenced. phaZPst was composed of 1,728 bp encoding a protein of 576 amino acids. Analyses of the N-terminal amino acid sequence and the matrix-assisted laser desorption/ionization–time-of-flight (MALDI-TOF) mass spectrum of the purified enzyme s
American Society for Microbiology.
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36. Constitutive Expression of the β-Ketothiolase Gene in Transgenic Plants. A Major Obstacle for Obtaining Polyhydroxybutyrate-Producing Plants1
Polyhydroxybutyrate (PHB) is a member of a class of thermoelastic polymers called polyhydroxyalkanoates that serve many bacteria as intracellular storage molecules for carbon and energy. Transgenic plants provide a potential means of producing this polymer cost-effectively. To date, however, few reports of the successful production of this polymer have been
American Society of Plant Physiologists.