National Repository of Grey Literature 177 records found  beginprevious100 - 109nextend  jump to record: Search took 0.00 seconds. 
Addition of probiotics to baby food products
Dudrová, Markéta ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
This Diploma thesis deals with preparation of probiotic cultures Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium breve enriched with prebiotics meant for application in baby food products. Natural extracts from matcha, moringa, young beat, young barley, chlorella and spirulina were selected as prebiotics. The theoretical part is focused on probiotic bacteria, their biological effects and their effects on the child´s body. The experimental part deals with the cultivation of probiotic bacteria with plant extracts, monitoring their viability and stabilization in an encapsulated form. Mixtures of probiotic cells with prebiotics were encapsulated into alginate particles to increase stability. Some of the alginate particles were processed by freeze drying. Mixtures of probiotic cultures with plant extracts were subjected to model human digestion by the action of model digestive juices in unencapsulated, encapsulated and lyophilized form. Selected extracts of plant materials were characterized in terms of amount of total and reducing sugars, total phenolic substances, individual phenolic substances and antioxidant activity. Further, two baby commercial dietary supplements containing probiotics were selected, which were characterized in terms of cell number and viability. Probiotic products were also subjected to model digestion.
Preparation and characterization of modern wound covers
Balášová, Patricie ; Pernicová, Iva (referee) ; Skoumalová, Petra (advisor)
This diploma thesis is focused on the study of bioactive wound dressings. During the thesis, hydrogel, lyophilized and nanofiber wound dressings were prepared. Hydrogel and lyophilized wound dressings were prepared on basis of two polysaccharides – alginate and chitosan. Nanofiber wound dressings were prepared by spinning polyhydroxybutyrate. All prepared wound dressings were enriched with bioactive substances, which represented analgesics (ibuprofen), antibiotics (ampicillin) and enzymes (collagenase). Into hydrogel and lyophilized wound dressings were all the mentioned active substances incorporated, whereas nanofiber wound dressings were only with ibuprofen and ampicillin prepared. The theoretical part deals with the anatomy and function of human skin. There was explained the process of wound healing and also there were introduced available modern wound dressings. The next chapter of the theoretical part deals with materials for preparing wound dressings (alginate, chitosan, polyhydroxybutyrate) and with active substances, which were used during the experimental part of this thesis. In the theoretical part, the methods of preparation of nanofiber wound dressings and also the methods of cytotoxicity testing used in this work were presented. The first part of the experimental part of this thesis was focused on preparing already mentioned wound dressings. Then, their morphological changes over time and also the gradual release of incorporated active substances into the model environment were monitored. The gradual release of ampicillin was monitored not only spectrophotometrically, but also by ultra-high-performance chromatography. In wound dressings, in which collagenase was incorporated, was also the final proteolytic activity of this enzyme monitored. The effect of the active substances was observed on three selected microorganisms: Escherichia coli, Staphylococcus epidermidis and Candida glabrata. The cytotoxic effect of the active substances on the human keratinocyte cell line was monitored by MTT test and LDH test. A test for monitoring the rate of wound healing – a scratch test – was also performed.
Development and preparation of antimcrobial nanostructure biomaterials
Drabíková, Nela ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
The presented diploma thesis deals with the optimalisation of preparation and the preparation of combined nanostructured antimicrobial biomaterials itself. In the theoretical part, a review focused on used materials and consequently preparation of nanoparticles and nanofibers was elaborated. Furthermore, the used antimicrobial substances – curcumin and ampicillin, and the principle of cytotoxicity assay were described.In practical part the optimalisation process is described. Furthermore the safety of prepared materials and used antimicrobial substances on HaCaT cell line was tested, in order to confirm their possible further use in cosmetic and pharmaceutical industry. Great part of the thesis deals with evaluation of the antimicrobial activity of used substances and prepared combined nanomaterials on multiple microorganisms from grampositive bacteria, gramnegative bacteria and yeasts. Also the release speed of antimicrobial substances from prepared nanomaterials was determined by spectrophotometer. The amount of released ampicillin from prepared nanomaterials was determined by liquid chromatography.
New possibilities in wound healing
Nováková, Laura ; Szotkowski, Martin (referee) ; Skoumalová, Petra (advisor)
The diploma thesis is focused on the study of fibrous wound dressings prepared by electrospinning method from natural biopolymers. Three active ingredients were added to the dressings: ampicillin, ibuprofen and collagenase, which are responsible for relieving pain, reducing the risk of infection and selectively removing necrotic tissue in the wound. The theoretical part describes the therapeutic dressings currently available on the market and the most common methods of nanofiber production. The experimental part evaluates the optimization of the preparation of gelatin, alginate and chitosan fibrous wound dressings, which were subsequently enriched with active substances and their gradual release into the model environment was determined spectrophotometrically. Antimicrobial effects against E.coli and S. epidermidis strains andantifungal activity against C. glabrata yeast were monitored. Finally, two cytotoxicity tests on the human keratinocyte cell line HaCaT confirmed the safety of the prepared products, which can serve as bioactive skin dressings in the future.
Preparation of organic fibers with the addition of algae extracts
Tuhrinská, Terézia ; Skoumalová, Petra (referee) ; Němcová, Andrea (advisor)
The presented bachelor thesis is focused on the preparation and characterization of organic fibers with an admixture of pre-prepared extracts of microalgae and cyanobacteria containing valuable active compounds. The theoretical part describes selected metabolites of microalgae and cyanobacteria, methods of their analysis, the issue of encapsulation and incorporation of active substances into nanofibers and presents some methods of their preparation. In the experimental part of this thesis, selected strains from the CCALA collection were first cultured. Subsequently, aqueous, ethanol and hexane extracts of biomass from cultured and commercial microalgae and cyanobacteria were prepared. The prepared extracts were spectrophotometrically evaluated in terms of the concentration of chlorophylls, carotenoids, antioxidants, polyphenols, and total proteins present. In addition, 96 % ethanol extracts were subjected to more accurate analysis of chlorophylls and carotenoids by HPLC. The highest antioxidant activity was observed for aqueous extracts. Gelatin nanofibers containing selected extracts were formed by electrospinning method. The formed fibers were examined afterwards to identify a mass fraction of incorporated microalgal and cyanobacterial substances. The fibers were further tested for antioxidant activity with the TEAC assay. The most pronounced antioxidant effect was detected for the fiber with incorporated aqueous extract of the cyanobacterium Arthrospira maxima. Finally, the fibers were tested for their safety in contact with human cells. The amount of fibers used did not show any cytotoxic effect on human keratinocytes and the tested materials can thus be considered safe for application in cosmetics.
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.
Preparation and characterization of food and cosmetic products containing selected vitamins
Kubošová, Jana ; Pavelková, Renata (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis deals with the preparation and characterization of encapsulated forms of lipophilic vitamins in model conditions, focusing on cosmetic and food applications. The theoretical part describes the individual vitamins, their physiological effects, physical and chemical properties, sources and sequels of hypo/hypervitaminoses. Furthermore, their contribution in medicine, food industry and cosmetics, methods of determination and in the last part of the encapsulation method are discussed. Special attention is dedicated to the technique of particles encapsulation using liposomes, which was used in the practical part. The experimental part is focused on the study of liposomes of selected substances of vitamin nature. Namely, the issue of cholecalciferol, tocopherol and -carotene was addressed, for which a suitable method of determination was introduced. Subsequently, encapsulation of these substances and characterization of the prepared liposomes took place. Their size, stability and encapsulation efficiency, which reached high percentages, were determined. Liposomes were further put to the stability tests in digestive juices and model medium simulating cosmetic products. During the measured time, the release of encapsulated substances into the surroundings and their gradual degradation was monitored. At the end of the work, analytes were extracted from real foods and cosmetic products and the measured concentrations were compared with the declared values.
Preparation and characterization of foods and food supplements containing selected vitamins
Krupičková, Lucie ; Hoová, Julie (referee) ; Skoumalová, Petra (advisor)
The thesis is focused on preparation of protected form of vitamins for aplication to food and diatery supplemets. The theoretical part characterizes vitamins and describes their role in human organism. Furthermore, this chapter summarizes different methods of determination vitamins soluble in water and encapsulation of substances into liposomes. The last sections are focused on functional foods and dietary supplements. In experimental part, an optimalization of determination method was made. Selected vitamins were encapsulated into liposomes. Size, stability, encapsulation efficiency, long-term stability and long-term encapsulation efficiency after two weeks was determined there. All prepared liposomes were found to be stable enough. Furthermore, the vitamin solutions, liposomes and lyophilized particles were analyzed during the process of model digestion. The active forms of vitamins were degraded during the model digestion of vitamin solutions. Vitamins were gradually released from the liposomes and lyophilized particles into the digestive juice. The analysis of content declared by producer was executed for functional foods and dietary supplements. Finally, applications of protected form of vitamins into the food and dietary supplemets were created.
Preparation of edible antimicrobial packaging
Kozubová, Petra ; Dzurická, Lucia (referee) ; Skoumalová, Petra (advisor)
This bachelor’s thesis is focused on preparation and characterization of eatable packaging. Eatable packaging consists of two components, antimicrobial component and base of packaging. The task of eatable packaging is to protect product against antimicrobial attack and to extend durability of the product. As antimicrobial components were used water and oil extracts of several herbs (mint, nettle, lavender, cinnamon, cloves, vanilla, ginger and rhinoceros). Oil extracts were also encapsulated into liposomes for better application. Firstly, concentrations of polyphenoles and antioxidants of extracts were determined. Oil extract of clove contained the highest concentration of both determined substances. Encapsulation efficiency, stability and size of liposomes were tested too. All prepared liposomes were stable and relatively of the same size. Also high encapsulation efficiency was observed. Next, antimicrobial activity of prepared extracts and liposome particles against yeast Candida glabrata and two bacteria strains Escherichia coli and Staphycococcus epidermidis was tested and the high antimicrobial activity reported mainly all tested liposomes. Then alginate, chitosan and carboxymethylcellulose and their combinations respectively were used as bases of packaging. Created film had to meet several parameters, especially suitable sensory properties such as pleasant taste and smell, as well as invisibility, gloss, affordability and suitable manipulability. Combination of 2% carboxymethylcellulose and 1% alginate in a ration of 2:1 with liposomes of mint as antimicrobial component achieved the best results.
Use of plasma jet for wound healing
Dvořáková, Eva ; Márová, Ivana (referee) ; Skoumalová, Petra (advisor)
This diploma thesis was focused on the possibility of using a plasma nozzle to accelerate the wound healing process. The benefits of using low-temperature plasma in medicine or biomedical applications are known from many studies, and low-temperature plasma is already used to sterilize medical devices, materials or surgical instruments. Some studies also report a high potential of usinh plasma nozzle in the treatment of skin wounds. In the experimental part of this work, an in vitro wound healing test was performed using two different low-temperature plasma sources. Source No. 1 was a surface wave microwave discharge and source No. 2 was a torch microwave discharge. An in vitro scratch healing test was performed on a monolayer of HaCaT keratinocytes and testing was performed using various parameters. The influence of the plasma treatment time was monitored, as well as the influence of the plasma discharge power and also the influence of the argon working gas flow. Especially when using a torch microwave discharge, faster wound healing was recorded at most of the parameters used compared to the control. Thus, it can be said that this source appears to be potentially suitable for faster wound healing. Furthermore, in the work using the MTT cytotoxicity test, the viability of skin cells after their plasmination was also monitored using the same conditions as in the in vitro wound healing test. When performed in the standard MTT assay, none of the settings or sources used showed any cytotoxic effects on keratinocytes. LDH cytotoxicity tests were also performed concurrently to verify the accuracy of the MTT assays. The results of both tests agreed and the use of low-temperature plasma in skin treatment can be considered as safe. Overall, the results show that the plasma nozzle can find use in medicine in the healing of skin wounds and chronic defects as a potentially fast, inexpensive and effective method.

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