Gas Permeable Chromatography (GPC)
The molecular weight and the polydispersity index are important parameters that will determine the quality of the polymer. The PHB extracted using chloroform was analyzed using GPC and the weight average molecular weight (Mw) obtained was 1.04 x 106. This value hinted that PHB synthesize by C. necator H16 cultivated with CPKO as sole carbon source was of relatively high Mw. Since it has been acknowledged that chloroform extraction cause negligible degradation of PHB; therefore these values were assumed to be intact molecular weight. In order to evaluate the effect of biologically recovery method on Mw, the PHB granules was subjected to GPC analysis and the Mw achieved was 1.23 x 106. Interestingly, polymer granules with slightly higher Mw were obtained with biological recovery method. The polydispersity index (Mw/ Mn) which represents the molecular weight distribution was also examined. However, relatively higher Mw attained with biological recovery method, the (3.01) when compared to chloroform extraction (1.28).
Differential Scanning Calorimetry (DSC)
The thermal properties of powdered faeces were investigated by DSC analysis because this information is important in polymer processing. The melting (Tm) and glass transition temperature (Tg) of the PHB present in the faeces was measured to be 167 °C and 3.92 °C respectively. The melting temperature of the biologically recovered PHB was found to be slightly lower when compared to values (173 - 180 °C) that were reported in the literature (Doi et al., 1995; Hahn et al., 1995; Sudesh et al., 2000).Yet, the attained value was close to the range of 160-171 °C that has been reported by Vallapil et al (2009) using different recovery methods.
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...g, Y. and Lee, S. (1995) Recovery and characterization of poly(3-hydroxybutyric acid) synthesized in Alcaligenes eutrophus and recombinant Escherichia coli. Appl Environ Microbiol 61, 34-39.
Hahn, S.K. and Chang, Y.K. (1995) A themogravimetric analysis for poly(3-hydroxybutyrate)
quantification. Biotechnology Techniques 9, 873-878.
Hahn, S.K., Chang, Y.K., Kim, B.S. and Chang, H.N. (1994) Optimization of microbial poly(3-hydroxybutyrate) recover using dispersions of sodium hypochlorite solution and chloroform. Biotechnol Bioeng 44, 256-261.
Waslien, C.I. and Calloway, D.H. (1969) Nutritional Value of Lipids in Hydrogenomonas eutropha as Measured in the Rat. Appl Environ Microbiol 18, 152-155.
Yu, J. and Chen, L.X. (2006) Cost-effective recovery and purification of polyhydroxyalkanoates by selective dissolution of cell mass. Biotechnol Prog 22, 547-553.
Makadia HK. & Siegel SJ., 2011. Poly Lactic-co-Glycolic Acid (PLGA) as Biodegradable Controlled Drug Delivery Carrier. Polymers, 3, 1377-1397
coli cells were grown at 37 degrees Celsius with calcium ions. These cells were then incubated in ice and placed into 4 polypropylene tubes. Each tube consisted of 25 microliters of E.coli cells. Two of the four were labeled with (+) while the other two were labeled (-). Positive was with samples that contained 100 pg/ microliter of pGLO, while negative was for the samples that did not. The 4 tubes were incubated in ice for 30 minutes, then heat shocked for 30 seconds at 42 degrees Celsius. The 4 tubes were then returned to the ice bath for 5 minutes. After the removal, .975 microliters of LB media was added to each tube at room temperature. The tubes were then shook at 225 RPM at 37 degrees Celsius for one hour. 300 microliters of cells were then extracted from the tubes and then placed in agar plates. The cells were spread across the plate and the incubated overnight at 37 degrees
Separations are important techniques in chemistry that are used to separate various components of a mixture. They are carried out by mixing two immiscible liquids containing certain solutes together in a separatory funnel, allowing them to separate, then extracting the distinct layers that form. The ratio of the concentration of solute present in the upper layer to the concentration in the lower layer is called the partition coefficient. The efficiency of a separation is described by this partition coefficient. If the coefficients for the two layers are largely different, then the separation can be carried out in a single step. If they aren’t, a more complex process is necessary.1,2 Countercurrent chromatography is a technique used carry out separations in these kinds of cases. It uses a continuous liquid-liquid partitioning process to streamline the usual extraction procedure.
...id, acetic acid, formic acid, H₂ and CO₂ as fermentation products which increases ecological, industrial and basic bioenergetics interests in this particularly thermophilic bacterial specie.
Talaro , K., & Chess, B. (2012). Foundations in microbiology. (8th ed., pp. 563-564). New York, NY:
Webster's Dictionary defines polychlorinated biphenyls (PCBs) as any of several compounds that are produced by replacing hydrogen atoms in biphenyl with chlorine, having various industrial applications and are poisonous environmental pollutants that tend to accumulate in animal tissue. They have a high resistance to excessive temperatures and do not disingrate in water. Because of these qualities, they can be useful in paints, lubricants, and most commonly, as a dielectric in capacitors.
Piringer, O., & Baner, A. (2008). Plastic packaging: interactions with good and pharmaceuticals. New York: Wiley-VCH.
The purpose of this experiment was to learn and preform an acid-base extraction technique to separate organic compounds successfully and obtaining amounts of each component in the mixture. In this experiment, the separation will be done by separatory funnel preforming on two liquids that are immiscible from two layers when added together. The individual components of Phensuprin (Acetylsalicylic acid, Acetanilide, and Sucrose as a filler) was separated based upon their solubility and reactivity, and the amount of each component in the mixture was obtained. Also, the purity of each component will be determined by the melting point of the component.
For bacteria to be utilised to its full potential and to meet the demands of quantity need for the production of foods and medicines it is key that experts are able to firstly distinguish what type bacteria is need for a certain production and secondly, and very importantly, how to reproduce that bacteria to create enough of it needed for mass production of a certain product.
Stout, M.A, et al. "Microbiology Lab Notebook". Lab handbook. University of Texas. Arlington. 2014. Print.
Up to present date there are many polymer hosts [1] have been discovered and some examples are
Multiplication of attached organisms leads to confluent growth and biofilm formation. Adherent bacteria synthesise extracellular polymers.
By taking a Carbon Dioxide, rich substance and mixing it with a yeast, solution fermentation will occur, and then it could be determined if it is a good energy-producer. In this study glacatose, sucrose, glycine, glucose, and water were used to indicate how fast fermentation occurred. The overall result shows that monosaccharides in particular galactose and glucose were the best energy source for a cell.
...sing Procion Red H-8BN that was coupled Sepharose 6B (1.96 mol dye/g moist weight gel). According to their report only when Zn(II) ions were present there was quantitative binding between the enzyme and the dye-Sepharose. Binding in very low levels occurred when these ions did not exist. Chelating agents, like EDTA, in combination with a pH change were used for the enzyme elution from the column. Additionally, Cibacron Blue F3GA-attached poly(EGDMA-HEMA) microspheres were used for the partial purification of methylotropic hydroxypyruvate reductase from a bacterial extract that had not been processed. The main characteristics of these dye-affinity microspheres are that they present really good adsorption and also they can be utilized with good results for the process of big volumes of extracts or culture medium in a liquid phase, where the target protein is present.
...-KLGA three different kind of methods have been used by researchers, In first method which is known as Single-strain processes, strains which belong to genera Gluconobacter, Acetobacter, Ketogulonicigenium, Pseudomonas, Erwinia, and Corynebacterium have been used. (Urbance et al., 2001[11]; Sugisawa et al., 1990[12]; Sonoyamaet al., 1982[13]; Isono et al., 1968[14]). , In the second method mixture of cultures have been used by different researchers (Xu et al., 2004[15]; Nogami et al., 1987[16]), In this method they have used two stage fermentation process in which d-glucose is oxidized to 2,5-diketod-gluconate by Erwinia or Acetobacter strains in the first step while in second step 2,5-diketo-d-gluconate is converted in to 2-KLGA by a strain Corynebacterium. Sonoyama et al. (1982)[17] and in the third method genetically engineered strain have been used[10].