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Encapsulation of probiotics and prebiotics for use in nutritional products for children
Šnajdarová, Karolína ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The Diploma thesis deals with designing of probiotic dietary supplement for children with strains Lactobacillus acidophilus and Bifidobacterium breve and with prebiotics. Used prebiotics were Inulin, Chia fiber, Bamboo fiber, Chlorella + Spirulina and Yakon syrup. The theoretical part is focused on probiotics, prebiotics and their biological influence. In experimental part the possibilities of encapsulation into alginate particle and lyophilisation of probiotic cells were observed to find their good form to final nutritional product for children. Several types of probiotic with addition of prebiotics were tested in model conditions of gastrointestinal tract. It was found that addition of prebiotic highly increases viability of probiotic cells and their resistance to model conditions of gastrointestinal tract. In this case, the best prebiotic was found in Yakon syrup. The prebiotics were also characterised in terms of nutritional composition, amount of total and reducing sugars, oligosaccharides, proteins, lipids, polyphenols and chlorophyll were obtained. Finally, Chia fiber, Chlorella + Spirulina and Yakon syrup were chosen as prebiotics with best characterisation/properties. In conclusion, a dietary supplement with lyophilized alginate particles containing probiotic cells and with the most appropriate prebiotics were designed. Forms of the product were powder and gummy-bear.
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The Use of Asbestos, Remediation of Contaminated Areas and the Risk of Impact on the Human Organism
Štípek, Radek ; Bendl, Jiří (advisor) ; Mihaljevič, Martin (referee)
The work deals with the uses of asbestos minerals, methods of safe disposal of asbestos and the disease burden caused by exposure to asbestos fibers, of which the most dangerous is crocidolite. Attention is paid to the physical-chemical and structural properties, classification and explanation of the processes of their formation, indicating areas of the Czech Republic and abroad. Describes the history of asbestos use since ancient times to the 20th century, including mass balance asbestos consumed in the technosphere that over the past hundred years, amounts to almost 194 million tons. It then focuses on building fire protection, insulation and other products with different content of asbestos in the world which total over 3000 and registered on the characteristics of asbestos substitute materials, such as ceramic, glass and carbon fibers, aramids, wollastonite, vermiculite and perlite. Describes methods for determination of asbestos fibers in the air, water and soil as a complete course of rehabilitation of contaminated objects. Asbestos fibers pose a risk to human health in the form of asbestosis, first diagnosed in 1900, pleural hyalinosis, lung cancer and mesothelioma of the pleura, where the first evidence of association with exposure to asbestos dates back to 1955 and on the basis of which...
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Lymnaeid snails: hemocyte activities and their changes caused by Trichobilharzia infections
Jindrová, Zuzana ; Horák, Petr (advisor) ; Bilej, Martin (referee)
Molluscs as well as all other invertebrates rely on innate immune response only. Their internal defense system is capable of destroying most pathogens. However, there are some exceptions, e.g. some snails serve as intermediate hosts for some trematodes. Trematodes are able to develop inside these snails due to intervention in the snail internal defense system. The submitted thesis describes hemocyte activities of two lymnaeid snails, Lymnaea stagnalis a Radix lagotis, and the influence of Trichobilharzia regenti infection on R. lagotis hemocytes. Hemocytes of both species exposed to various chemicals produced different amounts of H2O2 and NO. The response varied between both lymnaeid species. The amount of circulating hemocytes was elevated in R. lagotis snails due to T. regenti infection. However, the infenction attenuated hemocyte activities monitored by us. Hemocyte basal NO production was decreased as well as phagocytosis of bacteria, cell adherence and pseudopodia formation. Toxicity of L. stagnalis plasma against T. regenti miracidia was also described. Mechanisms used by trematodes to interact with the snail internal defense system will help us to understand why one species is suitable for the develepment of the trematode whereas another closely related species kills it. Powered by TCPDF (www.tcpdf.org)
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Use of cell cultures to testing of natural substances of plant origin
Ručková, Michaela ; Kostovová, Iveta (referee) ; Márová, Ivana (advisor)
The presented bachelor thesis is focused on preparing aqueous and oil extracts of plant origin, their characterization and testing of their cytotoxicity and genotoxicity. The theoretical part contains basic information about plants and kinds of spices or tea that were used. Description of used methods of liposome preparation and encapsulation of active substances, measurement of antioxidant activity, particle characterization, cultivation of cell cultures and the principle of cytotoxicity and genotoxicity tests used in this thesis is included. Phenolics and flavonoids content was determined using the spectrophotometry. Antioxidant activity was evaluated spectrophotometrically as well. By ultrasonic homogenization method, liposomes were prepared and active agents were encapsulated into these vesicles. Encapsulation efficiency and stability of active substances were measured by spectrophotometry. By DLS method, size of particles was determined. Particle stability was derived from the zeta potential value. Important part of the bachelor thesis was cultivation of human keratinocytes. The cytotoxicity of extracts and liposomes was assessed by MTT assay on human cell cultures. The genotoxicity of extracts and liposomes was defined using SOS Chromotest on model organism, genetically modified E. coli. In conclusion, the potential use of prepared liposomes in the cosmetic or pharmaceutical industry has been proposed.
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Use of antimicrobial products of animal origin in cosmetics
Puškárová, Radka ; Bokrová, Jitka (referee) ; Márová, Ivana (advisor)
The Bachelor thesis deals with characterization a whey in free and encapsulated form and its application to cosmetic industry. The theoretical part is focused on characterization of whey, especially on its antimicrobial properties, and use of this effect in selected cosmetics preparatives. Further, methods of encapsulation and particles characterization were described. In the experimental part, antimicrobial properties of whey were tested by two different methods. Whey was encapsulated into three different types of particles: liposomes, alginate and chitosan. Long-term colloid stability of particles during one and three weeks of storage in model conditions was tested. Further, particles were added into model skin creams. Long-term sedimentation stability of these emulsions was analyzed by analytical centrifuge.
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Application of microencapsulation techniques in development of novel controlled-release systems.
Karásková, Iva ; Mravec, Filip (referee) ; Sedláček, Petr (advisor)
This diploma thesis deals with application of microencapsulation techniques in development of hydrogel controlled-release systems in which the main role is played by humic acids, biopolymer chitosan, compound fertilizer NPK and 3-indoleacetic acid. This paper continues my bachelor thesis topic about utilization of polyelectrolyte complexes. The aim of this work was to develop a literature review focusing on the microencapsulation techniques and according to its results optimize the method. Microencapsulation was performed with a commercial encapsulator BUSCHI B-395 Pro and a release of individual components into a water was measured. An amout of released substances was measured by UV-VIS method and HPLC analysis. Practical part also included testing of repeated swelling and drying. It was found that suitable composition and combination of ingredients form hydrogels for further use in agriculture.
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Development of a new type of energy drinks containing natural active components
Vysoká, Marie ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The aim of this thesis is the development and preparation of a new energy drink. The theoretical part of the thesis focuses on the comparison of the drinks available in market, the presentation of the main active ingredients and the proposal of enriching the new energy drink. It also describes the possibility of using an encapsulation and the method used to determine specific compound in energy drink or encapsulated particles. In the experimental part of the work, at the beginning, the main content of energy drinks were characterized, for instance caffeine, sugar, polyphenol and vitamin C. Subsequently the energy drink based on selected types of loose teas that were enriched with the encapsulated extract of acai, acerola, maca, goji and ginseng was designed. All extracts contained large amounts of polyphenols and antioxidants. In addition, acerola extracts contained very high amounts of vitamin C. Two types of particles, alginate particles and liposomes were prepared for encapsulation. For all particles, encapsulation efficiency, size, stability, and antioxidant activity were determined. Long-term stability was then monitored within three months. The particles were also exposed to artificial gastric, pancreatic and bile juice. All tested particles showed very good encapsulation efficiency. In terms of long-term storage stability in an aqueous environment. Particularly liposome particles, which also showed high stability by zeta potential measurement, were suitable. On the contrary, in case of alginate particles, when stored in an aqueous medium, the release of active substances occurred. Finally, an energy drink was created and subjected to sensory analysis. The best energy drink was based on black or green tea with alginate particles acai, goji and ginseng.
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Preparation and characterization of biomaterials with natural UV filtres
Pavelková, Renata ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
This presented diploma thesis is focuses on preparation and characterization of biomaterials with natural UV filters. The theoretical part is aimed at effects of sunlight on the skin and how to avoid these effects by using cosmetic products. The materials and methods for extraction of lipid part of the selected vegetable and microorganism species and methods for preparation and characterization of nanoparticles and emulsions were characterized. The practical part deals with extraction of lipid part of selected vegetable and microorganism species. The liposome particles with encapsulated active compounds were prepared. The particle size, polydispersity index, colloidal stability, encapsulation efficiency, SPF, antioxidant capacity, phospholipid content and cytotoxic effect on human keratinocytes were observed. These particles were used for preparation of the resulting emulsions. Their protection level on UV light were set and stability were tested by using analytical centrifugation.
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Use of encapsulation techniques for production of food for infants
Hoová, Julie ; Čarnecká, Martina (referee) ; Skoumalová, Petra (advisor)
The Diploma thesis deals with use of selected probiotic strains Lactobacillus acidophilus and Bifidobacterium breve in different forms in food for infants. The theoretical part is focused on describing probiotics, encapsulation methods and intestinal gut microbiota of infants. Further, characterization of individual periods of infant feeding and food for infants were introduced. In experimental part the possibilities of encapsulation and lyophilisation of probiotic cells were observed. Probiotic cells were encapsulated into alginate particles. The encapsulator was used for preparation of particles and the most appropriate particles were prepared by encapsulation nozzle with size of 300 µm. Moreover, probiotics viability was monitored by Flow Cytometry, Fluorescence Microscopy and by cultivation (CFU method). Viability of probiotics was monitored during long-term storage in selected food for infants. The appropriate shelf life of non-lyophilized alginate particles in real food have been set at 1 to 2 months. Lyophilized alginate particles could be stored for more than 3 months. Finally, the stability of the particles and viability of encapsulated and non-encapsulated cells in the gastrointestinal tract conditions were also examined. The viabilities of lyophilized cells and cells encapsulated in lyophilized particles were also compared. From the results obtained, non-encapsulated probiotic bacteria cells are more susceptible to negative effects of digestive juices, the percentage of dead probiotic cells after digestion was approximately 80 %. On the other hand, alginate particles showed cell protection from digestive juices, after incomplete cell releasing from particles the percentage of dead probiotic cells did not exceed 20 %. After adequate rehydration, similar results were gained with lyophilized alginate particles. Lyophilized alginate particles have been determined to be the most suitable application form for infants’ food.
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