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Production of mcl-PHA by selected bacteria
Eremka, Libor ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The aim of this work is to study the possibility of microbial production of polyhydroxyalkanoates with medium chain length (mcl-PHA). For production two bacterial strains were used: Pseudomonas putida and Pseudomonas aeruginosa. Theoretical part of bachelor thesis deals with the biosynthesis of polyhydroxyalkanoates, their material properties and microbial producers. In experimental part selected bacteria were cultivated on different substrates to evaluate their ability to utilize various carbon sources and accumulate mcl-PHA. Content and composition of mcl-PHA accumulated in biomass were analyzed by gas chromatography with FID. Pseudomonas putida produced more mcl-PHA in medium containing canola oil as sole carbon source when compared with Pseudomonas aeruginosa. P. putida produced 2,11% mcl-PHA in medium containing glycerol as carbon source.
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Breathing Rate Estimation from the ECG and PPG Signals
Blaude, Ondřej ; Němcová, Andrea (referee) ; Kozumplík, Jiří (advisor)
This bachelor’s thesis is focused on breath rate estimation. In this thesis, methods of breath rate estimation from the ECG and PPG signal are described and implemented. In the first two chapters the basics of ECG measurements are described, as well as the measurements of the respiratory system activity and the PPG signal. The third chapter then describes the ECG/PPG-derived respiratory signal estimation methods, later on the breath rate determination. In the fourth chapter, chosen methods are implemented and the created algorithms are applied on real data from the BIDMC database.
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Probiotics and prebiotics - a study of interactions, effects and co-encapsulation
Vrtná, Monika ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
This diploma thesis is focused on encapsulation probiotics and co-encapsulation with some types of prebiotics. In theoretical part is aimed to probiotics, their general characteristics and application of probiotics in food industry. There are described prebiotics and their classification, there is described principles of encapsulation and encapsulation techniques. Methods, which are used for analysis of particles and encapsulation components were introduced too. The experimental part describes methods of prebiotics characterization by high performance liquid chromatography, thin layer chromatography and spectrophotometric methods. Cultivation of probiotics with prebiotics - hydrolyzed and non-hydrolyzed wad tested. Using flow cytometry cell viability was measured too. Finally probiotics and prebiotics were encapsulated, mainly by encapsulator machine. Long-term stability of particles during 6 week storage was observed. The particles were exposed to effect of artificial intestinal, gastric and bile juices.
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Production of pigments and lipid substances by microorganisms on waste substrates of the food industry
Hladká, Dagmar ; Němcová, Andrea (referee) ; Szotkowski, Martin (advisor)
The presented study is focused on production of carotenoids, lipids and other substances by carotenogenic yeasts and autotrophic algae. Studied strains were cultivated in media with different composition, including waste substrates from food industry. Studied strains were cultivated under stress conditions to enhance the production of desired metabolites. The theoretical part deals with the information about yeasts and algae, with the information about monitored metabolites such as lipids, carotenoids, ergosterol, ubichinon or chlorophyll. Furthermore, the theoretical part deals with possible methods of metabolite analysis. The experimental part deals with the description of cultivation of yeats and algae. Also experimental part is focused on the description of individual methods. The result part deals with comparition of production of biomass, metabolits and lipids. The selected strains of yeast were Sporidiobolus pararoseus, Sporidiobolus metaroseus, Sporobolomyces roceus, Phaffia rhodozyma and Dioszegia hungarica. The selected strains of algae were Desmodesmus acutus, Desmodesmus quadricauda, Scenedesmus dimorphus and Chlamydomonas reinhardtii. We were optimized conditions for metabolites and lipids production. Optimal medium, which contained coffee hydrolyzate was with carbon to nitrogen ratio C/N 25. Nitrogen in higher concentration had negative effect on production of lipids. The most suitable strain for effective use of nitrogen in different concentrations was Chlamydomonas reinhardtii. The most suitable strain of yeast for effective use of coffee hydrolyzate was Sporidiobolus metaroseus.
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Identification of DNA from plant foods using molecular techniques
Papala, František ; Langová, Denisa (referee) ; Němcová, Andrea (advisor)
The aim of this bachelor thesis is the identification of plant DNA in a complex matrix using molecular techniques. The work first focuses on a search of literature sources concerned with molecular techniques of DNA identification. Next, it deals theoretically with methods of isolation and characterization of plant DNA. Specifically, we shall work with blueberry DNA. In the experimental part, DNA from four commercial products was isolated and subsequently subjected to PCR and HRM analysis.
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Preparation of natural food supplements for children's nutrition
Kubisová, Petra ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The presented diploma thesis is focused on complex characterization of chosen superfoods and subsequent composition of supplement suitable for children´s nutrition. Different kinds of superfoods were chosen for analyses, such as: barley grass (Hordeum vulgare), wheat grass (Triticum aestivum), moringa (Moringa oleifera), matcha tea (Camellia sinensis), microalgae chlorella (Chlorella pyrenoidosa), spirulina (Arthrospira platensis), flax seeds (Linum usitatissimum) and sesame seeds (Sesamum indicum). The theoretical part is focused on children´s nutrition issue and the most common food allergies and intolerances. Also, children food products legislation and characterization of chosen samples are included in theoretical part. Main macronutrients, such as saccharides, lipids and proteins, were analysed in the very beginning of experimental part. Fibre, fructan and -glucan, which have a high impact on intestinal microbiome and whole process of digestion, were analysed as well. However, barley grass was the best evaluated sample by containing 205,5 mg/g of insoluble fibre; 152,57 mg/g of fructans and 18,76 mg/g of -glucans. Finally, for complex nutritional profile, also samples pigments were analysed. Spectrophotometry, HPLC chromatography, gas chromatography and other analytical techniques were performed for experiments.
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Testing of biological effect of glucans on cell lines in vitro
Šimková, Eva ; Holub, Jiří (referee) ; Němcová, Andrea (advisor)
The aim of this bachelor thesis is isolation and testing of -glucans from selected strains of yeast. In the theoretical part, characterisation of -glucans, microbial production of -glucans by yeast, determination of polysaccharides, exopolysaccharides and in vitro testing are described. Yeast have a cell wall made up of -glucans and -glucans are known for their healing properties. In the experimental part of this work deals with characterization of selected biomass yeasts in different forms and comparison of their effects and the amount of -glucans in each form. Stains of Metschnikowia pulcherrima, Cystofilobasidium infirmominiatum and Rhodotorula kratochvilovae have been selected for this thesis. Subsequently, the thesis deals with the isolation and testing of isolated -glucans from a selected lyophilised strain of yeast Rhodotorula kratochvilovae. The selected strain was isolated in 2 ways. The first method of isolation that was more friendly to conformation of -glucans due to the effect of ultrasonic homogenization of cells. The second method of isolation was less friendly to -glucans, using acid and base to homogenise them. Analyses of both extraction methods confirmed the presence of isolated -glucans, however it was found that the recovery of both methods was relatively low and requires further optimisation of the procedure. Overall, the better extraction procedure was the second method. A sample of this extract was further tested on the HaCaT cell line. The results of the pilot tests confirmed the cytotoxicity of the extract obtained by us.
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Preparation of some application formula of antimicrobial substances
Krempaský, Kamil ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The main aim of this study is to determine antimicrobial activity of herbal extracts and also encapsulate these extracts and lysozyme to liposomes. The extracts were prepared from above ground part of wormwood (Artemisia absinthium), aerial part of breckland thyme (Thymus serpyllum), the root of purple coneflower (Echinacea purpurea), liquorice (Glycyrrhiza glabra), corolla of pot marigold (Calendula officinalis) and berries of sea buckthorn (Hippophae rhamnoides). In all extracts antioxidant activity and the amount of total polyphenols and flavonoids was determined. All of these extracts and also lysozyme were used for encapsulation to liposomes. Prepared liposomes were then tested for their stability. Further, encapsulated as well as free extracts were tested for their antimicrobial activity on Escherichia coli, Serratia marcescens, Micrococcus luteus and Bacillus subtilis. Extract from Echinacea purpurea showed the highest antimicrobial activity.
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Antimicrobial substances from plants and their application in acne preparations
Alexová, Adéla ; Byrtusová, Dana (referee) ; Němcová, Andrea (advisor)
The aim of the bachelor thesis is a determination of selected active substances of various plants and their possible application in cosmetic products for acne. In the theoretical part, an inventory of active substances including their effects in cosmetic products has been developed. Furthermore, the work is focused on characteristics of certain types of plants, mechanisms of antimicrobial effects and the emergence and treatment of acne. In the experimental part of this work the contents of biologically active substances, antioxidant and antimicrobial activity in extracts from selected plant species are characterized, namely from flowers of Levandula angustifolia, Matricaria chamomilla, Calendula officinalis, Syzygium aromaticum, leaves of Salvia officinalis and leaves of Rosmarinus officinalis. The plant extracts are also tested in different mixtures. Plant extracts and mixtures are incorporated into a recipe of acne cosmetic products. Their inhibitory effect against Propionibacterium acnes which causes acne and against representatives G+, G- and yeast Micrococcus luteus, Escherichia coli and Candida glabrata is observed. From the results it is clear that the best products against acne are micellar water and possibly skin lotion. The biggest amount of active substances is in cosmetic products which contain Matricaria, Syzygium and Rosmarinus. Overall effect of active substances is lower in cosmetic products than in 100% extracts.
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The negative effect of raw foods due to possible microbial contamination
Šťastná, Martina ; Hlaváček, Viliam (referee) ; Němcová, Andrea (advisor)
Raw diet is the current trend in nutrition, mainly because of the consumption of a balanced diet with a high proportion of health benefits. The basis is the consumption of fresh foods that have not undergone a heat treatment exceeding 42 - 45 ° C. The topic of the bachelor thesis is the general characterization of raw diet, safety of possible microbial contamination and determination of important nutrients and active substances contained in raw products. There are described the most widespread types of meals, approximation of raw diet in terms of its advantages and disadvantages. Also, there are described the most important bacteria, yeasts and molds occurring on fruits and vegetables. By selected methods described in the theoretical part, some nutrients and active ingredients in raw stick samples were determined. The experimental part describes the procedures and principles for the determination of these substances, and last but not least, the real-time PCR methods, agarose gel electrophoresis and the method of sample inoculation for selective solid media that have brought closer the possibility of occurrence of undesirable microorganisms in raw bars and cake. Despite the large number of benefits of raw food consumption and products made from it, it is necessary to take care of its health also in terms of possible contamination by microorganisms. The risk is that the food is not free from unwanted microorganisms during preparation. This is the reason why the raw products are consumed in the shortest possible time after opening, because they become easily a nutrition source for different types of microorganisms due to their composition.
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