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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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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 and use of selected nanoparticles in cosmetics
Hoová, Julie ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The Bachelor thesis is focused on preparation and use of selected nanoparticles in cosmetics. The theoretical part deals with general characterization and use of caffeine, phenolics and vitamin C in cosmetics. Further, characterization of liposomes and possibilities of encapsulation of active substances gained from natural sources were introduced. In experimental part liposomes with encapsulated active substances were prepared by three different techniques. Encapsulation efficiency was determined by HPLC/PDA, phenolics spectrophotometrically and vitamin C by titration. Prepared particles were monitored for size and stability by dynamic light scattering. Furthermore, long-term stability of liposomes in model conditions was evaluated as the amount of the active substances released during incubation. In this work was found out that from all tested samples co-encapsulated liposomes are probably the best application form which can be used in face lotion or gel. Co-encapsulated liposomes exhibited relatively high encapsulation efficiency, good stability and thanks to quality of active substances they meet customer’s requirements of cosmetic industry.
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Preparation of encapsulated enzymes for cosmetics application
Bokrová, Jitka ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
Presented diploma thesis is focused on testing of an appropriate form of encapsulated enzymes intended for application in cosmetic and pharmaceutical industry. For encapsulation, proteolytic enzymes bromelain, papain and collagenase were used. These enzymes were encapsulated into alginate and chitosan microparticles prepared by an encapsulator and packed into liposomes. Encapsulation effectiveness was evaluated by analysis of total proteins. Particles stability was evaluated in model and real conditions by photometrical analysis of released proteins. Proteolytic activity of released enzymes in model and real conditions were observed too. Alginate and chitosan microparticles prepared by the encapsulator were found as an appropriate form of encapsulated enzymes designed to wound healing. Encapsulation effectiveness of these particles and stability in model conditions were good in comparison with liposomes. Hydrogel and water-oil emulsion were used for analysis of particles stability at real conditions. Hydrogel was found as a good option for preservation of particles as well as proteolytic enzyme activity. Emulsion made particles less stable and proteolytic activity of enzymes decreased rapidly. Encapsulation enables long-term stabilization of biologically active compounds as well as possibility of targeted transport and controlled releasing. Presented diploma thesis suggests possibilities of application encapsulated enzymes in designing more effective formulations for wound healing.
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Application of nanoparticles and nanofibers with active compound in cosmetics
Pavelková, Renata ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
Presented bachelor thesis is focused on application of nanoparticles and nanofibers with active compound in cosmetics. The theoretical part is aimed at effect of UV radiation on the skin and compounds that are used in photo protection of the skin. The materials and methods used in nanoparticle and nanofiber preparing were characterized. The experimental part deals with preparing of liposomes and marinosomes with active compound. Particles size, stability measured using zeta potential and stability in model environment were observed. Finally, pilot experiments of optimization of nanofibers preparation using electrospinning were carried out.
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Preparation of food supplements for children containing probiotic bacteria and fruit components
Vetchá, Vendula ; Bendová, Agáta (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis is focused on the preparation of supplementary food with probiotic culture and fruit components. The aim of this work was to determine which of the selected extracts will affect the growth of probiotics and also will contain a certain proportion of phenolic compounds, flavonoids, vitamin C and show antioxidant effects. The theoretical part of the work is focused on the intestinal microbiota, the issue of probiotics and the characterization of encapsulation methods of probiotics. We used extracts of teas and fruit syrups in the experimental part. The antimicrobial activity against model microorganisms Escherichia coli, Micrococcus luteus, Staphylococcus epidermidis and Serratia marcescens was analyzed. Interaction of probiotic bacteria Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium breve in extracts were tested. After model digestion, cell viability of probiotic bacteria in combination with extracts was examined during and after digestion. In the last part, encapsulated particles containing probiotics and a mixture of tea and syrup were prepared.
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Encapsulation of vitamins and provitamins into nanoparticles
Martinusíková, Katarína ; Wikarská, Monika (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis is focused on the encapsulation of vitamins in liposomes and the subsequent observation of the properties of this form. The theoretical part is focused on the history of vitamins, their classification into groups, but mainly the general characterization of all vitamins. It describes their function in the human body, the consequences of their deficiencies and also the sources of their income. It also describes the technique of encapsulation in liposomes and their characterization and use in the food industry. The experimental part is focused on the preparation of specific liposomes of vitamins and their mixtures. These prepared liposomes are subsequently characterized by properties such as size, stability and encapsulation efficiency. Long-term stability of prepared liposome particles over 2 and 5 weeks were also investigated. In the conclusion of this thesis are summarized all the results of observations and the subsequent suggestion of the possible use of this technique in food products.
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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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Encapsulation of probiotics for use in nutritional products for children
Šmídová, Veronika ; Hudečková, Helena (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis is focused on optimization and development of probiotic food supplement with attractive look and active ingredient, like prebiotic or “superfood”, which are there for afford useful substances for organism. In the theoretical part is focused on probiotics and its encapsulation, also on prebiotics, which are used for work and screening probiotics food supplements in our market. The practical part is focused on optimization of composition of new probiotic food supplement, polysaccharide particles in the shape of a teddy bear were prepared. At first, the basic composition was optimized, as the best alginate-agar particles were determined. Addition of nutritionally valuable ingredients was also optimized. Particles with inulin, acerola, chia fiber, yacon syrup, chlorella and spirulina were prepared. Another part of this work was focused on the determination of the viability of probiotic bacteria Lactobacillus acidophilus and Bifidobacterium breve in various forms and after exposed to model digestion. The highest viability of the cells was measured after encapsulation of lyophilized cells into a polysaccharide particle. Prepared particles were finally subjected to a sensory analysis.
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Study of natural antimicrobial mixtures and their stabilization
Vejrostová, Petra ; Veselá, Mária (referee) ; Márová, Ivana (advisor)
Present diploma thesis is focused on natural antimicrobial substances. The aim of the experimental part of thesis was testing of antimicrobial activity of selected natural substances in free and encapsulated forms, preparation of particles and monitoring of their long-term stability. Various teas extracts (aqueous, ethanoic and DMSO) and aqueous herbs extracts were used as plant antimicrobial substances. Liposomes and chitosan particles with encapsulated aqueous teas extracts were prepared by ultrasonication. Encapsulation efficiency, size, stability and antioxidant activity for all particles were specified. Consequently, within a two months period, long-term stability for these particles was monitored. Spectrophotometric method for determining total polyphenols was used for evaluating encapsulation efficiency as well as for monitoring of long-term stability. The DLS method was used for determination of size and stability of particles. Antioxidation activity was monitored by using spectrophotometric method using ABTS. For testing antimicrobial activity of various types of teas, herbs extracts and their mixtures and combianitons with lysozyme and antibiotics, broth dilution methods were used while using both Gram positive and Gram negative bacterial test strains. Antimicrobial activity of prepared particles was also monitored, the antimicrobial activity was especially significant with the chitosan particles. Suitable combinations of natural substances whatever with antimicrobial or antioxidation effect either in free or encapsulated form could be used for applications for example in cosmetics industry, food processing or in medicine.
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