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Showing 1 to 19 of 19 for “"Polyhydroxyalkanoate"”.
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Production of polyhydroxyalkanoate copolymers from plant oil
Polyhydroxyalkanoates (PHAs) are carbon storage polymers produced by a variety of bacteria. The model organism for studying PHA synthesis and accumulation is Ralstonia eutropha. This species can be used to convert renewable resources into PHA bioplastics, which can serve as biodegradable …
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Novel Polyhydroxyalkanoate blends: their characterisation and possible applications
Polyhydroxyalkanoates (PHAs) are polyesters consisting of 3-hydroxyalkanoic acids synthesised by numerous bacteria as storage compounds, in the presence of excess carbon, under nutrient limiting conditions. PHAs are biodegradable and biocompatible polymers that exhibit a variety of properties …
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Ruminal Degradation of Polyhydroxyalkanoate and Poly(butylene succinate-co-adipate)
… plastic impaction in domestic ruminants. Using polyhydroxyalkanoate (PHA) and poly(butylene succinate-co-adipate) (PBSA) biodegradable materials for feed storage products such as bale netting could reduce the incidences and effects of polyethylene-based plastic impaction in ruminants. The …
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Improved Polyhydroxyalkanoate Production from Selected Volatile Fatty Acids using Cupriavidus necator
This study aimed to develop methods to improve PHA production from selected volatile fatty acids (VFAs) and to improve the understanding of the PHA production process by pure culture bacterial fermentation using Cupriavidus necator. Optimisation strategies involved the following investigations …
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Biosynthesis and characterisation of polyhydroxyalkanoate biopolymers and their oligomers for circular economy
Polyhydroxyalkanoates (PHAs) are biodegradable bioplastics that can potentially replace non-biodegradable petroleum-based plastics. However, the high production cost of PHAs which is associated with the high cost of starting substrate extraction solvents limits its integration into large scale …
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Investigation of polyhydroxyalkanoate production by an activated sludge microbial consortium treating artificial dairy wastewater
Petrochemical plastics/polymers are a common feature of day to day living as they occur in packaging, furniture, mobile phones, computers, construction equipment etc. However, these materials are produced from non-renewable materials and are resistant to microbial degradation in the environment. …
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Metagenomic characterization of Candidatatus Defluviicoccus tetraformis TFO71, a tetrad-forming organism, predominant in an anaerobic-aerobic membrane bioreactor with deteriorated biological phosphorus removal
… to the synthesis and degradation of glycogen and polyhydroxyalkanoate (PHA), which function as energy and carbon storage compounds. Both TFO71 and Candidatus Accumulibacter phosphatis (CAP) UW-1, a representative polyphosphate-accumulating organism (PAO), have PHA metabolism-related genes with …
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Extracting transcriptional regulatory information from DNA microarray expression data
… commercially interesting, biodegradable polymer polyhydroxyalkanoate (PHA). We have created DNA microarrays with [approximately]97% of the Synechocystis genome represented in duplicate to monitor the cellular transcriptional profile. These arrays are used in time-series experiments of differing …
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Mechanistic investigation of polyhydroxybutyrate (PHB) synthases and elucidation of PHB biosynthesis and degradation process in Wautersia eutropha H16
Polyhydroxyalkanoate (PHA) synthase from various bacterial organisms is able to catalyze the polymerization of (R)-hydroxyalkanoate-CoAs into high molecular weight PHAs under nutrient- limited conditions in the presence of a carbon source. PHA synthases are representative of enzymes involved in …
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Understanding and exploiting bacteriophage-host interactions for the control and detection of listeria monocytogenes
… biocontrol agents. The key findings showed that polyhydroxyalkanoate bionanoparticles displaying the full-length endolysin of phage vB_LmoS_293 or the amidase domain of this lysin, lysed and inhibited the growth of L. monocytogenes strain 473 at 37 ºC and 22 ºC. Phages were also exploited for the …
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Structural enzymology of bacterial carbon fixation and storage
… carbon monoxide dehydrogenase (CODH) and polyhydroxyalkanoate synthase (PhaC). CODH is a key component of the Wood-Ljungdahl pathway of carbon fixation, catalyzing the reversible reduction of CO₂ to CO, and has garnered interest as a possible tool in environmental remediation and biofuels …
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Microbial synthesis of 3,4-dihydroxybutyric acid, 3-hydroxybutyrolactone and other 3-hydroxyalkanoic acids
… platform employs the reactions of the natural polyhydroxyalkanoate synthesis pathway with new substrates, taking advantage of natural enzyme promiscuity for the stereospecific synthesis of a variety of 3HAs of desired carbon chain length and substituents. Using this platform, we have now …
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Biosynthesis of polyhydroxyalkanoates for cardiac tissue engineering applications
… biodegradable, biocompatible and elastomeric polyhydroxyalkanoate, was studied as a potential material for cardiac tissue engineering. Mcl-PHAs are an alternative source of polymers produced by Pseudomonas sp. As Gram-negative bacteria, Pseudomonas sp. contains lipopolysaccharides in the …
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Novel Biomaterials for Applications in Cartilage Tissue Engineering
… for evaluation were P(3HO-3HD-3HDD) (a type of polyhydroxyalkanoate), trans-1,4-polyisoprene (TPI), the blend of these (named PHA + TPI), as well as two chemically modified versions of hydroxypropyl methylcellulose, or HPMC (named HPMC 2,6 and HPMC triple). These materials were analysed at …
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Advancing wastewater valorization using anaerobic membrane bioreactors with bioaugmentation and ion-exchange, and bio-plastic production
… recovery via mixed microbial culture (MMC) polyhydroxyalkanoate (PHA) production. The first study presented in this dissertation investigated the application of bioaugmentation in the acid-phase of a two-phase AnMBR treating primary sludge to improve solids removal and overall process …
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Studies on Methylmalonyl-CoA Mutase from Escherichia coli
… to the development of a metabolically engineered polyhydroxyalkanoate producing strain of B. cereus. The intention was to provide the bacteria with a natural intracellular source of propionyl-CoA, leading to the production of the P(3HB-co-3HV) copolymer from structurally non related carbon sources …
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Effects of Fused Filament Fabrication Process Variables on Microstructural Alignment and Intra-layer Properties in PLLA
… a multi-material transition from dual PLLA and polyhydroxyalkanoate (PHA)/PLLA blend layers to a single PLLA layer, orientating the interface towards the printing direction. This transition was imaged using polarised light microscopy, and had a total thickness of ≈ 125 μm. The results confirmed …
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Produkce polyhydroxyalkanoátů z vybraných odpadních substrátů
Predložená bakalárska práca sa zameriava na štúdium produkcie polyhydroxyalkanoátov (PHA) baktériami Burkholderia sacchari a Burkholderia cepacia a taktiež faktorov, ktoré produkciu ovplyvňujú. Hlavnou skúmanou oblasťou bola produkcia PHA na substráte z kukuričnej siláže. V teoretickej časti bola …