National Repository of Grey Literature 43 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Biodegradable Nanogels from Biocompatible Polymer Precursors
Oleshchuk, Diana ; Proks, Vladimír (advisor) ; Uchman, Mariusz Marcin (referee) ; Trachtová, Štěpánka (referee)
This doctoral thesis focuses on the development and application of hydrophilic, biocompatible, and biodegradable poly(amino acids)-based nanogels as a new type of delivery system. Within this Ph.D. thesis, nanogelation via horseradish peroxidase (HRP)/H2O2-mediated crosslinking in an inverse miniemulsion was investigated and optimized. The effect of three different surfactants (SPAN 80, TWEEN 85, and AOT) with various concentrations (5 wt% - 25 wt% relative to the dispersed phase with step 5 wt%) on the nanogelation of polyglutamine-based polymer precursor modified with tyramine units (PHEG-Tyr) was investigated. The results indicated that the stabilization of nanogel was most effectively achieved using 20 wt% of the nonionic surfactant SPAN 80. The hydrodynamic diameter (Dh) determined by dynamic light scattering (DLS) was 230 nm, and this size range was further confirmed to be between 200 and 300 nm using (nanoparticle tracking analysis) NTA. Analysis using transmission (TEM) and cryogenic transmission electron microscopy (cryo-TEM) techniques revealed that the nanogel in its dry state exhibited almost spherical shape with a number-average diameter (Dn) of 26 nm and dispersity (Ɖ) of 1.91, and in the frozen hydrate state, the nanogel displayed a larger size with Dn = 182 nm and Ɖ = 1.52,...
Alternative beverages of probiotic character
Moravec, Štěpán ; Langová, Denisa (referee) ; Trachtová, Štěpánka (advisor)
Bachelor thesis deals with explanation of therm probiotics, properties of each probiotic bacteria genuses. preparation of coffee and tea, and also deals with probiotic coffee and tea and molekular diagostic methods which were used during bachelor thesis. There were used mikrobiological and molecular diagnostic methods for analysis of probiotic coffee and teas. Namely for confirmation of bacterial genus Bacillus and for confirmation of survavibility of Bacillus during high temperatures. Presence of bacterial DNA in samples of coffee and teas was confirmed by conventional PCR method and by real-time PCR method. Survibility of genus Bacillus during high temperaturewas confirmed by PMA-PCR method.
Paraprobiotics, postbiotics and other -biotics
Crha, Richard ; Šálek, Petr (referee) ; Trachtová, Štěpánka (advisor)
The theoretical part of the thesis deals with a wide range of microorganisms and substances derived from probiotics. Based on recent publications, probiotics, prebiotics, synbiotics, paraprobiotics, postbiotics, pharmabiotics, psychobiotics and oncobiotics are defined. Furthermore, the purpose and use of the mentioned -biotics is specified for the current understanding of their function. In the experimental part, DNA was isolated from a sample of probiotic capsules using a commercially available bacterial kit and magnetic particles. Its purity and concentration were then determined spectrophotometrically. Using the isolated DNA as a matrix for conventional PCR and detection on agarose gel, the composition of the probiotic product as declared by the manufacturer was demonstrated. Finally, the PMA-PCR method was optimized.
Microbial diversity of breast milk and its influence on the gut microbiome of infants
Novotná, Jana ; Vítová, Eva (referee) ; Trachtová, Štěpánka (advisor)
Breast milk is considered the most important source of nutrition for infants and newborns due to its content of all the necessary nutrients and bioactive components that positively affect the child's immune system. The theoretical part of my work deals with the microbial composition of breast milk and its transformation depending on the stages of breastfeeding and other factors. The experimental part is focused on the identification of selected bacterial strains in breast milk and stool of a breastfed child and a child fed an artificial milk diet. Collection strains of bacteria belonging to the genera Bifidobacterium, Lactobacillus, and Candida were used for the analysis. DNA was isolated by phenol extraction, using magnetic carriers and a commercial kit. The presence of bacterial DNA was proved by q-PCR analysis using genus-specific primers for selected bacteria.
Study of the chemical profile of wine of Riesling variety
Šumberová, Michaela ; Trachtová, Štěpánka (referee) ; Vítová, Eva (advisor)
This diploma thesis focuses on the chemical profile and authentication of the geographical origin of varietal wine Rhine Riesling obtained from 4 Moravian wine regions. In the experiment, 20 wine samples were analysed with 5 instrumental analytical methods – aromatic compounds were determined by HS-SPME-GC-MS, phenolic compounds by HPLC-MS, total phenolic content by MAS, and elemental analysis by ICP-OES and ICP-MS. In total 36 aromatic compounds were detected, from which 7 were varietal terpenes and 2 of them C13 norisoprenoids. The total phenolic content for the Rhine Riesling wine was measured in the concentration range of 174,22–380,96 mg·l-1. Gallic acid (0,41–34,99 mg·l-1), catechin (0,05–7,44 mg·l-1), epicatechin (0,03–4,14 mg·l-1), caffeic acid (0,14–2,05 mg·l-1), and coumaric acid (0,30–4,04 mg·l-1) were the specific measured phenolics. In total 18 elements were measured in Rhine Riesling wine, macroelements K > P > Mg > Ca > Na with concentrations above 10 mg·l-1, microelements Al > Fe > Zn > Mn > Sr > Cu in the concentration range 0,1–10 mg·l-1, and trace elements Ni > Cr > V > Pb > Mo > Co > Cd in the concentration 0,0001–1 mg·l-1. Potassium was the most abundant element (386,37 mg·l-1). The results were used for the parametric and nonparametric univariate analysis of variance (ANOVA) and multivariate principal component analysis (PCA). Ni60 (p = 0,0029), ethyl benzoate (p = 0,0060), and diethyl succinate (p = 0,0247) were statistically the most significant parameters influenced by the wine region for the significance level = 0,05. Out of the 57 measured variables 7 parameters were identified as statistically significant and used for PCA graphic representation of the samples. PCA results show, that the varietal wine’s origin can be authenticated by chosen chemical compounds and chemometric methods.
New trends in the use of probiotics in cosmetic products and their characterization
Dvořáková, Monika ; Němcová, Andrea (referee) ; Trachtová, Štěpánka (advisor)
Probiotic products have always been, in the form of various dairy products, a part of our diet. In recent years, they also became prominent in the pharmaceutical sector, where they can often be found as food supplements, and in the cosmetic sector, where they are being added to intimate hygiene and skin care products. The first part of the thesis consists of conducting a theoretical research in the field of probiotics, microbiome and other possibilities of where we can find probiotic organisms in cosmetic products. Further, a part of the thesis is devoted to methods of cultivating and isolating bacterial DNA from the following products: Benton, Mechnikov, La Rosche-Posay creams and Benton and Neogen masks, in sufficient quality for subsequent PCR amplification. DNA was isolated using magnetic carriers, a commercial kit, and phenol extraction. The presence of bacterial DNA was proved by a q-PCR analysis using genus-specified primers of selected bacteria. Genus identification corresponded with the information declared by the manufacturer. To conclude, a PCR and propidium monoazide dye were used in combination for quantification of viable and dead cells, and a HRM analysis was performed.
Use of advanced molecular biology techniques for detailed characterization of probiotic bacteria from a dietary supplement
Folwarczná, Tereza ; Trachtová, Štěpánka (referee) ; Smetana, Jan (advisor)
The aim of the diploma thesis was the identification of probiotic bacteria from a probiotic food supplement in the form of syrup. DNA was isolated from the complex matrix of the product in sufficient purity and quality suitable for the real-time PCR method followed by PCR-HRM. Specific primers for the genera Lactobacillus, Bifidobacterium and Streptococcus and at the species level for the species Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus plantarum, Lactobacillus reuteri, Bifidobacterium animalis, Bifidobacterium breve, Bifidobacterium bifidum, Bifidobacterium lactis, Bifidobacterium longum, Bifidobacterium infantis and Streptococcus thermophilus were used for amplification by real-time PCR and PCR-HRM. After optimizing the conditions for specific primers, all declared bacteria were detected in the product.
Production of magnetic particles by microorganisms
Chvalkovská, Eva ; Mgr. Martina Mikešová, Ph.D. (roz. Pravečková) (referee) ; Trachtová, Štěpánka (advisor)
This thesis focuses on the magnetic nanoparticles produced by bacteria. These are two types of bacteria. First of them we can find in an industrial environment that produce magnetic nanoparticles using magnetosomes. Magnetosomes are units containing nanocrystals and are surrounded by a lipid layer. They are made up of chains and work as a compass. In this thesis I deal with possibilities of cultivation od these bacteria, acquisition of magnetosomes and subsequent processing. The second type is bacteria living in the human body, they start to produce magnetic nanoparticles after the addition of trigger, such as silver nitrate. Bakteria which can produce silver or ferrous nanoparticles are Bacillus sp, Escherichia coli, Lactobacillus casei ssp. casei and Lactobacillus fermentum. Experimental part of bachelor thesis focused on the production of silver nitrate in concetration of 0,1; 1; 2; 4 mM. The bacteria that have been shown to produce silver nanoparticles are Lactobacillus casei ssp. casei CCM 7088T a Lactobacillus casei ssp. casei CCM 7089 a Lactobacillus rhamnosus CCM 1825T.
Methods for detection of antimicrobial properties of lactic acid bacteria
Vránová, Petra ; Němcová, Andrea (referee) ; Trachtová, Štěpánka (advisor)
Lactic acid bacteria are classified as probiotics producing substances that act against microorganisms. These antimicrobial substances include organic acids, carbon dioxide, hydrogen peroxide and bacteriocins. Currently, the focus is on bacteriocins, which are used in the food and pharmaceutical industries. The aim of this thesis is creating an overview of antimicrobial properties of lactic acid bacteria, methods of their determination and their applications in the food industry. The experimental part deals with identification of lactic acid bacteria present in selected samples of bacterial DNA. In addition, we tested for bacteriocin Gassericin K7A-producing gene. Molecular diagnostic methods such as real-time polymerase chain reaction (qPCR) and conventional polymerase chain reaction were used to distinguish bacterial DNA as well as the bacteriocin.
Magteic particles and their applications in biotechnology
Knápková, Monika ; Konečná, Jana (referee) ; Trachtová, Štěpánka (advisor)
The thesis is focused on the magnetic particles which are used in several biotechnological applications. The theoretical part deals with the specific properties of these nanoparticles and materials of which the nanoparticles can be made. There are also mentioned some of the biotechnological applications of magnetic particles. During the experimental part, selected types of magnetic particles were used to isolate nucleic acid. The quality of the isolated DNA with respect to purity was evaluated using the polymerase chain reaction and its modifications. High resolution analysis (HRM analysis) was also used to verify the quality of the isolated DNA and to resolution Lactobacillus casei and Lactobacillus rhamnosus. DNA isolation using magnetic carriers was successful. Commercially available MPG microcarriers and magnetic microparticles Fkol 77ox were the most suitable. In terms of purity magnetic nanoparticles F79/L3-PLL were the most suitable for the DNA isolation. The resolution of bacterial strains of Lactobacillus casei and Lactobacillus rhamnosus was not successful.

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