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Preparation and characterization of nanoparticles with encapsulated antimicrobial component
Dohnalová, Marie ; Strečanská, Paulína (referee) ; Márová, Ivana (advisor)
This bachelor thesis is focused on the preparation and characterization of particles with encapsulated natural substances with antioxidant and antimicrobial properties. Selected antioxidants were anthocyanins, eugenol and vitamin E, as one of the most powerful antioxidants. At the same time, antimicrobial agents were chosen, in this case eugenol. In the theoretical part, individual active substances, materials for the preparation of particles, methods of their preparation were characterized and the principle of determining the safety of used materials. In the experimental part, selected active substances were characterized and the preparation of particles was optimized. Two types of liposomes were prepared, for which the encapsulation efficiency, size and stability were determined. Also prepared aqueous extracts of blueberries and blackberries were prepared, for which total anthocyanin content has been determined. The extracted substances from the plant material were encapsulated into alginate particles. Furthermore, the gradual release of active substances from particles into model environments using a spectrophotometer was determined. During the gradual release of active substances from the particles, the antioxidant effect was also monitored, in which it was possible to observe a decrease with the passage of time. The antimicrobial effect of active substances and liposomes against model microorganisms Escherichia coli and Micrococcus luteus was also tested. Cytotoxicity tests on human keratinocytes were performed on selected active substances, extracts and prepared nanoparticles, where it was proven that the selected materials are non-cytotoxic. Finally, a proposal for a possible application form in the form of an alginate hydrogel was created.
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Characterization of some natural substances with antimycotic effect
Plachá, Monika ; Hlaváček, Viliam (referee) ; Márová, Ivana (advisor)
The introduced bachelor thesis is focused on investigation of the effects of natural substances with potential antimycotic effects and characterization of their constituents. As a part of this work, an overview of mycosis, antimycotics and constituents of natural substances were introduced. Moreover, antifungal susceptibility and genus Candida were described. In the end of the theoretical part the liposomes and their characterization were described. In the experimental part general characteristics of some natural substances and antimycotic test were analyzed. Aqueous, ethanol, methanol and DMSO extracts were tested on yeast strain Candida glabrata. Aqueous extract of the cloves, cloves oil and their combination were encapsulated into liposomes. The encapsulation effectivity, long-term stability and their antifungal activity were determined too. Characterization of liposomes was identified by DLS. Finally, application of liposomes to a preparation of pharmaceutical and cosmetic preparations were presented.
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Encapsulation of active components and their applications in food industry
Malčíková, Hana ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The Diploma thesis is focused on encapsulation of bioactive compounds which are contained in selected superfoods for the purpose of application to childrens nutrition supplements. In view of the nature of selected samples, which are seaweed, walnuts, hemp seed and flax seed, the emphasis is put on the content of omega-3 and omega-6 acids. The theoretical part introduces topic of children food, further it describes the nature of selected superfoods and last but not least it contains screening of available childrens food supplements containing omega-3 fatty acids on the market. In the experimental part, an optimization of the appropriate type of extract was made. A 24 hour aqueous macerate and 20% ethanol macerate were selected for next analyzes. Samples were characterized by content of polyphenols, flavonoids and the antioxidant activity and they were used to forming of extracts were encapsulated into liposomes for which their encapsulation efficiency, stability and long-term stability have been tested. Hexan extracts were also prepared for the same reasons. It was found that liposomes of selected superfoods should not be stored for 12 weeks. The samples were used analyzed for the carbohydrate content by the duboise method, a protein content by the Kjeldahl method and the determination of the fatty acid profile by gas chromatography. Furthermore, the content of carotenoids and chlorophylls in algae samples was determined by spectrophotometry and this analysis was verified by high-performance liquid chromatography. The technique of high-performance liquid chromatography was also used to verified a content of polyphenols in the algae samples. Finally, a sensory analysis of prepared alginate supplements containing algae and cold-pressed oils was performer in combinations to achieve a higher omega-3 and omega-6 fatty acid content. The F01-labeled sample containing wakame algae was evaluated as the best one.
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Interaction of PHA-based particles and fibres with human cells
Tarageľ, Matej ; Bokrová, Jitka (referee) ; Márová, Ivana (advisor)
This bachelor thesis deals with the preparation and characterization of PHA based nanoparticles and nanofibers and their subsequent influence on the living human skin cell. Theoretical part is aimed at polyhydroxyalkanoates, preparation of PHA based nanoparticles and nanofibers and methods of their physical, biological and chemical characterization. Further, the theory of liposomes, their clasification, preparation and physical and chemical properties are discussed too. Next, the theoretical part focuses on the cultivation of human cells and general information on selected cell lines. The experimental part is focused on the optimalization of the preparation of liposomes and fibers enriched by PHA. Further, characterization of stability and interactions of these nanomaterials with human HaCaT cells was proved. Cytotoxic and genotoxic tests were performed and determination of concentration of phospholipids in prepared particles was realized too.
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Influence of some super-foods and their active components on human cells
Maslonková, Ivana ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
The presented diploma thesis is focused on the study of composition and biological effects of some super-foods. Theoretical part deals with basic information about chosen superfoods and their bioactive substances. Further, theoretical part describes the overview of vesicular systems used for encapsulation and the most common methods of particle characterization. A brief review of cell cultures and cultivation of human cells is presented as well as methods for cytotoxicity a genotoxicity testing. In the experimental section, aqueous and ethanol extracts of super-foods were prepared. These extracts were then encapsulated into liposomal and combined PHB particles. Super-food extracts were characterized by spectrophotometrical methods in order to determine the content of polyphenols, flavonoids, anthocyanins, carotenes, chlorophyll, tannins, and antioxidant activity. The physico-chemical characteristics of prepared liposomal and combined particles were determined too. The particles with encapsulated extracts were further tested using the MTT assay and SOS chromotest to describe their potential cytotoxic and genotoxic effects.
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Advanced microscopy in the research of colloidal systems
Valovič, Stela ; Venerová, Tereza (referee) ; Mravec, Filip (advisor)
This bachelor thesis is focused on dual-colour fluorescence cross-correlation spectroscopy. As a suitable combinations of fluorescenct dyes were designated this combinations: perylene + nile red, perylene + DiD and DiO + DiD. The funtionality of this method was veried by tetraspeck. The experiment of FCCS was performed on micellar surfactants solitions which proved to be unsuitable for this method. Consequently, liposomes with DiD and DiO incorporated in phospholipid bilayer were measured. The cross-correlation in liposomes was succesfuly measured.
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Phase-separated systems biopolymer-lipid
Kubalová, Barbora ; Pekař, Miloslav (referee) ; Mravec, Filip (advisor)
This diploma thesis deals with experimental study of interaction based on polymer-lipid system. The main goal was to investigate interaction leading to phase separation. Three anionic polyelectrolytes were selected for this purpose: sodium hyaluronate, sodium chondroitin-6-sulfate and sodium poly(4-styrenesulfonate). The liposomes were formulated by sonication of lipid – cationic 1,2-dipalmitoyl-3-trimethylamonium-propane (chloride salt) and zwitterionic 1,2-dipalmitoyl-sn-glycero-phosphocholine. It was found that the phase separation occured at specific ratio of DPTAP and selected polymer. It was also explored that the strong electrostatic interaction which leads to the phase separation can be weaken by increasing the ionic strength in the sample. As we aspected the systems contain the hydrophobic domain and therefore these are able to incorporate hydrophobic substances in their structure.
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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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Preparation of nanoparticles and nanofibers with antimicrobial components
Sosková, Simona ; Veselá, Mária (referee) ; Skoumalová, Petra (advisor)
The presented diploma thesis is focused on the preparation of new materials with antimicrobial effect. Liposomes and nanofibers from polyhydroxybutyrate containing clotrimazole and natural extracts with good antifungal and antioxidant effects were prepared. The theoretical part contains examples and short description of using nanoparticles and nanofibers in cosmetics and medicine and the description of plants which have positive and potential antimycotic effects. Moreover, methods for particles and fibers characterisation were shortly described. In the experimental part, natural water and lipid extracts were prepared and spectrophotometrically characterised for the content of polyphenols, flavonoids and the antioxidant activity. Liposomes and liposomes containtng PHB were prepared from selected extracts and the encapsulation effectivity, shortterm and longterm stability via determination of polyphenols were determined. Prepared particles were characterized with DLS method (size) and zeta- potential (stability). PHB nanofibers functionalised with selected lipid extracts and clotrimazole were prepared via electrospinning and forcespinning, and examined via FLIM and FTIR-ATR methods and spectrophotometry was used for antioxidant activity and release of active substances determination. Antifungal properties of prepared particles, extracts and fibers using the test system Candida glabrata were studied. Finally, cytotoxicity of selected samples was tested with MTT assay using human keratinocytes.
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