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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Identifikace probiotických bakterií ve farmakách / Identification of probiotic Bifidobacterium strains in dairy products

Zovčáková, Monika January 2010 (has links)
Lactobacilli are dominant bacteria of the vaginal flora. Lactobacillus-containing probiotics products are used for the treatement and profylaxis of bacterial urogenital infections. This work is focused on DNA identification and species identification of probiotic bacteria in 5 different vaginal tablets using molecular-genetic methods. Total DNA isolated from complex matrix of vaginal tablets was used for amplification in polymerase chain reaction. DNA was isolated from crude cell lysates by magnetic particles P(HEMA-co-GMA) and by method of phenol extraction. Identification of species of probiotic bacteria was verified using genus-specific and species-specific PCRs. Results of bacterial identification obtained by PCR were compared with declared specification given by producers. Bacteria of genus Lactobacillus were proved in all tablets whereus species identification was in accordance with the stated composition in 1 tablet only.
2

Magnetic Targeted Drug Delivery

Leach, Jeffrey Harold 24 February 2003 (has links)
Methods of guiding magnetic particles in a controlled fashion through the arterial system in vivo using external magnetic fields are explored. Included are discussions of applications, magnetic field properties needed to allow guiding based on particle characteristics, hemodynamic forces, the uniformity of field and gradients, variable tissue characteristics, and imaging techniques employed to view these particles while in transport. These factors influence the type of magnetic guidance system that is needed for an effective drug delivery system. This thesis reviews past magnetic drug delivery work, variables, and concepts that needed to be understood for the development of an in vivo magnetic drug delivery system. The results of this thesis are the concise study and review of present methods for guided magnetic particles, aggregate theoretical work to allow proper hypotheses and extrapolations to be made, and experimental applications of these hypotheses to a working magnetic guidance system. The design and characterization of a magnetic guidance system was discussed and built. The restraint for this system that balanced multiple competing variables was primarily an active volume of 0.64 cm3, a workspace clearance of at least an inch on every side, a field of 0.3T, and a local axial gradient of 13 T/m. 3D electromagnetic finite element analysis modeling was performed and compared with experimental results. Drug delivery vehicles, a series of magnetic seeds, were successfully characterized using a vibrating sample magnetometer. Next, the magnetic seed was investigated under various flow conditions in vitro to analyze the effectiveness of the drug delivery system. Finally, the drug delivery system was successfully demonstrated under limiting assumptions of a specific magnetic field and gradient, seed material, a low fluid flow, and a small volume. / Master of Science
3

Molekulární identifikace vybraných druhů bakterií mléčného kvašení a bifidobakterií v doplňcích stravy / Molecular identification of selected species of lactic acid bacteria and bifidobacteria in food additives

Riegelová, Kristýna January 2011 (has links)
Probiotic lactic acid bacteria and bifidobacteria are natural part of microflora of gastrointestinal tract. In the present, day they are grossly exploited in food processing industry. The aim of the work was molecular identification of bacteria of genus Lactobacillus and Bifidobacterium in complex matrices of two food additives. Total DNA was isolated from crude cell lysates by magnetic particles P(HEMA-co-GMA). Isolated DNA was amplified in genus-specific and species-specific PCRs. Amplicons were detected by agarose gel electrophoresis. Results were compared with declared specification given by producers in three different batches.
4

Identifikace bakterií druhu Lactobacillus acidophilus v probiotických výrobcích / Identification of bacteria of Lactobacillus acidophilus species in probiotic products

Sznapková, Veronika January 2012 (has links)
Probiotic lactic acid bacteria (LAB) are an important part of fermented dairy products, pharmaceuticals and food supplements. At present, rapid and accurate identification of bacteria is carried out using molecular biological methods based on DNA amplification. The aim of the thesis was to identify by non-cultivation bacteria of genus Lactobacillus and bacteria of species Lactobacillus acidophilus in complex matrices at total of seven different food supplements. Total DNA was isolated from crude cell lysates using magnetic carrier P(HEMA-co-GMA). Amplificability of DNA was verified by PCR using primers specific for the domain Bacteria. In next step isolated DNA was amplified using primers specific for the genus Lactobacillus and species Lactobacillus acidophilus to demonstrate the presence of this bacterial genus and species declared by the producers. The results of bacteria identification obtained by PCR were compared with declared specification given by the producers.
5

Izolace DNA v kvalitě pro PCR z mléčných výrobků pro dětskou výživu / Isolation of PCR-ready DNA from dairy products for baby nutrition

Mantlová, Jana January 2013 (has links)
The work was focused on isolation of PCR-ready DNA and the identification of probiotic lactic acid bacteria that were isolated from five milk product for infant nutrition. DNA was isolated from crude cell-lysates of the products by magnetic P(HEMA-co-GMA) microspheres. DNAs isolated from crude cell lysates of control strains using phenol extraction method were used as positive controls. Using PCRs DNA of genera Bifidobacterium and species B. animalis, B. bifidum, B. breve, B. infantis, B. longum and Streptococcus thermophilus species were identified in products. The results obtained are consistent with the data declared by the manufacturers.
6

Selektivní izolace bakterií rodu Lactobacillus z potravin / Selective isolation of of the genus Lactobacillus bacteria from foods

Novotná, Eva January 2012 (has links)
Probiotic lactic acid bacteria of genus Lactobacillus play an important role in the digestive tract of human. They are used in food processing and they are the part of food supplements. Lactic acid bacteria of the genus Lactobacillus can be identificated by polymerase chain reaction (PCR). Bacterial DNA was isolated from cell lysates of 4 synbiotic food suplements by magnetic particles P(HEMA-co-GMA). Isolated DNA was amplified by genus-specific and species-specific primers. Magnetic particles with immobilized antibodies against Lactobacillus bacteria were used in the next part of thesis. These particles were used for isolation target cells from products with their identification by genus specific PCR.
7

Izolace DNA z rostlinných tkání pro použití v polymerázové řetězové reakci / DNA extraction from plant tissues for polymerase chain reaction analysis

Trojánek, Zdeněk January 2013 (has links)
Extraction of nucleic acids is an important step for all molecular biological studies. The process of isolation of plant DNA is complicated due to the presence of polyphenols, polysaccharides and other metabolites. They can be co-isolated with DNA and act as PCR inhibitors. The aim of this study was to compare CTAB extraction procedure, Qiagen DNA easy kit, direct homogenization, carboxyl-functionalised magnetic non-porous HEMA based microspheres and combination of the above mentioned methods for DNA isolation from different plants. The DNA was evaluated regarding concentration, purity and amplification in PCR. All methods provided DNA that could be used in downstream PCR applications. However, there were differences regarding yield, purity, labour intensiveness and cost. Combination of direct homogenization and magnetic microspheres coated by carboxyl groups was isolated DNA from various plants and plant foods in a quality suitable for convectional PCR, real time PCR and restriction analysis. This method is fast, simple and does not require work with harmful substances.
8

Study of the Preparation of Mesoporous Magnetic Microspheres and Their Applications

Ericson, Mårten January 2009 (has links)
Treatment of wastewater using magnetic technology is a rising field. In this thesis, the latest research on the subject is reviewed and several adsorbents with different coatings, which impart them unique properties, are discussed. Separation of particles from aqueous solution using magnetic technology is more convenient compared to conventional techniques, such as filtration and centrifugation. The adsorbents described in this thesis are effective for adsorption of several types of contaminants, such as heavy metals and different types of dyes.    Magnetic microspheres were synthesised using porous polystyrene microspheres as template. The microspheres were first sulfonated using chlorosulfonic acid followed by stirring in the presence of ferrous chloride which then was oxidised and magnetic nanoparticles were formed on the surface.    The sulfonated microspheres had a surface area of 420 m2/g and the magnetic 175 m2/g, indicative of Fe3O4 nanoparticles were successfully formed in the pores. The weight fraction of the Fe3O4 nanoparticles in the magnetic microspheres was 33 %.    Adsorption and desorption studies of the cationic dye, methylene blue, using mesoporous magnetic microspheres were performed. The results show that the mesoporous magnetic microspheres have good ability to adsorb methylene blue at low concentrations. In a cycle study the adsorption efficiency were nearly 100 % throughout the study. Using a 6/4 EtOH/H2O with saturated KCl solution the desorption efficiency in the cycle study were about 95 %.      The microspheres were used as carriers for TiO2 in order to overcome the problem with the separation of TiO2 from solution. The TGA results show that the microspheres contained about 12 % of TiO2. The TiO2 coated microspheres were used for the photocatalytic degradation of phenol. However, the TiO2 microspheres did not work. This was a result from that the phenol had too little contact with the TiO2. A possible way of solving this problem could be to decrease the size of the microspheres, thus increase the surface area.    Lysozyme was adsorbed and separated using the porous microspheres. The lysozyme adsorption worked best at pH 9.6, which is the pI for lysozyme. The lysozyme could be extracted from the microspheres by using a pH 13 buffer. Also, by using MeOH/H2O and EtOH/H2O solutions with saturated KCl the lysozyme could be desorbed. An adsorption and desorption mechanism was also presented. / Vattenrening med magnetisk teknologi är en ny och alltmer uppmärksammad teknik. Magnetisk separation är ett enkelt och snabbt sätt att separera något från en lösning. Magnetisk separation är mer lätthanterligt jämfört med traditionell separationsteknik såsom centrifugering och filtrering.  Med porösa polystyren mikrosfärer som mall, syntetiserades magnetiska mikrosfärer. Först så sulfonerades mikrosfärerna med klorosulfonisk syra, följt av att de rördes om i en järnkloridlösning. Magnetiska nanopartiklar bildades i porerna och på ytan av mikrosfärerna.    Sulfonerade mikrosfärerna hade en specifik ytarea på 420 m2/g och de magnetiska 175 m2/g, detta indikerar att Fe3O4-nanopartiklar bildades på ytan och i porerna. Massfraktionen av Fe3O4 var 33 %.    Adsorption- och desorptionsstudier på de magnetiska mikrosfärerna utfördes. Färgämnet metylblått användes i studien. Resultaten visade att magnetiska mikrosfärerna hade en bra adsorptionsförmåga vid låga koncentrationer av metylblått. Cykelstudier visade att adsorptionsverkningsgraden var nära 100 % under flera adsorptionscykler. Desorptionsförsök med olika lösningsmedel visade att en mättad KCl 6/4 EtOH/H2O lösning gav en desorptions-verkningsgrad på ca 95 %.   Mikrosfärerna användes som mall och kärna för att syntetisera en TiO2-fotokatalysator, detta för att överkomma problemet som finns med separation av rent TiO2 pulver från lösning. TGA resultaten visade att mikrosfärerna innehöll ca 12 % TiO2. De syntetiserade TiO2-mikrosfärerna användes till att bryta ner fenol fotokatalytiskt. Dock fungerade inte detta experiment. En anledning var att fenolen hade för lite kontakt med TiO2. En lösning på detta problem är att använda mikrosfärer med högre specifik ytarea.    Proteinet lysozym användes som modellprotein för försök att separera proteiner från lösning genom att använda porösa mikrosfärer. Resultatet visade att lysozym kunde adsorberas vid pH 9.6. Med en pH 13 buffer kunde lysozymet sedan extraheras från mikrosfärerna. En mekanism för adsorptionen och desorptionen på mikrosfärerna presenterades.
9

Identifikace bakterií mléčného kvašení v tvrdých sýrech s využitím amplifikačních metod / Identification of lactic acid bacteria in hard cheeses using amplification methods

Herzogová, Jitka January 2008 (has links)
Diploma thesis was focused on identification of lactic acid bacteria of species Lactococcus lactis and subspecies Lactococcus lactis ssp. lactis and Lactococcus lactis ssp. cremoris using species and subspecies specific polymerace chain reaction (PCR). PCR method was used for identification of bacteria of species Lactococcus lactis in 10 samples of hard cheeses. The method of sample preparation was evaluated for hard cheeses with the aim to receive sufficient amount of cells for the preparation of crude cell lysates. Whole DNA in quality suitable for PCR was separated using magnetic microspheres P(HEMA-co-GMA) in the presence of polyethylenglycol (PEG 6000) and sodium chloride. DNA isolated by phenol extraction was used as control of DNA isolation. PCR was used to the analysis of 7 strains of Lactococcus lactis from Collection of dairy microorganisms Laktofora (CCDM). Altogether 5 or 2 strains were identified into subspecies Lactococcus lactis ssp. lactis and Lactococcus lactis ssp. cremoris, respectively.

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