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Preparation and application of nanoparticles and nanofibres with natural UV filters
Plachá, Monika ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
The presented diploma thesis is focused on preparation of nanoparticles and nanofibres with natural UV filters. Liposomes with encapsulated aqueous, ethanol and lipid extracts were prepared. Nanofibers from PHB containing lipid extract were prepared too. As a part of this work, an overview of natural sources with potential effects as UV filters were introduced. Moreover, nanoparticles and nanofibers and methods of their characterization were described. Size, polydisperse index and colloid stability of prepared nanoparticles were characterized via DLS. In experimental part aqueous, ethanol and lipid extracts were prepared from roasted coffee, green coffee and cascara. These extracts were spectrophotometrically characterized for the content of polyphenols, flavonoids, antioxidant activity, tannins and their SPF. Liposomes and liposomes containing PHB with these extracts were prepared and the encapsulation effectivity, short–term and long–term stability as well as SPF of nanoparticles were determined. Nanofibers from PHB containing lipid extracts were prepared via electrospinning and forcespinning methods. Prepared nanofibers were examined via FTIR–ATR. Antioxidant activity, short–term and long–term stability were determined spectrophotometrically. From selected nanoparticles, emulsions and gels were prepared and their SPF was also determined. Three types of emulsions with the best SPF were selected and tested on volunteers. Sedimentation stability of emulsions was tested by analytical centrifuge. Finally, cytotoxicity of selected nanoparticles and nanofibers was tested via MTT assay using human keratinocytes.
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Health effects of Czech beer
Bokrová, Jitka ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
The aim of this bachelor thesis was to study physiological effect of various kinds of lager beer and to compare these effects in Czech beer and several beers produced in foreign countries. In theoretical part Czech beer characteristics and biologically active compounds in beer are described. Quantification of total phenolics, total flavonoids, antioxidant activity and bitter substances was performed photometrically. The quantity of vitamin C was determined by high performance liquid chromatography with spectrophotometrical detection. Beer buffering capacity was analyzed by pH measurement in artificial stomach and intestinal liquid, respectively. Analysis of physiological effect was accomplished by analysis of proteolytic enzyme activity. The total of 22 samples (16 Czech and 6 foreign lager beers) was studied. In these samples levels of basic technological characteristics and buffering capacity were compared. Alcoholic and non-alcoholic beers were compared too. According to experimental data it was confirmed that consumption of Czech beer (mainly lager beer) positively influences digestion process and activity of digestive proteolytic enzymes.
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Food and cosmetic use of technical hemp
Puškárová, Radka ; Skoumalová, Petra (referee) ; Němcová, Andrea (advisor)
The thesis occupies with the use of hemp in cosmetics and in food processing. In the theoretical part hemp was characterized by the content of active substances. In the experimental part the thesis is concerned with characterization of two different hemp varieties Carmagnola and Ferimon in terms of presence of active substances. The next part focuses on preparation of cosmetic with hemp content. In cosmetic preparations and in the extracts the inhibitory effect against Propionibacterium acnes, Micrococcus luteus, Escherichia coli and Candida glabrata was tested. The content of fatty acids and vitamin E was determined in hemp seed. The results show that dried hemp flower extract contains the largest amount of active substances and has the greatest inhibitory effect against all tested bacteria except Candida there was no effect. Cosmetic preparations did not show almost any inhibitory effect because of low concentration of active substances. The hemp seed contained high amount of PUFA and essential fatty acids. Vitamin E was found out in all of three hemp oils.
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Isolation and characterization of natural active components and their application in food supplements
Šmídová, Veronika ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The diploma thesis is focused on the characterisation and isolation of naturally occurred active compounds, especially on lipophilic compounds. The next part of the thesis deals with enzymes and their encapsulation into alginate particles to suggest new enzymatic dietary supplement for children with optimal nutrient composition. The theoretical part is focused on the issue of child nutrition, accordingly the necessary nutrients that children need to grow without any health difficulties. It is also focused on the availability of enzymatic food supplements for children. Finally, the theoretical part deals with the lack of chosen natural substances and their effects in connection with cancer. In the experimental part, four types of oils obtained from seeds were characterized. The oils were obtained by two methods: cold pressing with a Yoda kitchen press and extraction in an organic solvent with Soxtherm. Seeds were linseed, sesame, pumpkin, and cumin. With these oils were characterized natural active substances, polyphenols, flavonoids, antioxidants, carotenoids, chlorophylls, and fatty acids. Liposomes were also prepared from selected extracts, in which an effect on intestinal tumour cells were observed. Furthermore, some enzymes were selected, and they were encapsulated into alginate particles with average size 450 µm. In these particles was specified encapsulation efficiency as well as the proteolytic activity after testing in digest juices. The last part of this thesis was focused on the optimization of a complete enzymatic food supplement with addition of alginate particles as enzyme carriers. Samples of these supplements were finally subjected to a sensory analysis.
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Use of hemp and its products in cosmetics and pharmacy
Žáčková, Kristýna ; Skoumalová, Petra (referee) ; Němcová, Andrea (advisor)
Hemp is a versatile usable plant which can be found in almost all branches of industry, but also in medicine. The subject of this thesis is the determination of selected active compounds of technical hemp and its products and their possible applications in cosmetics and pharmacy. In the theoretical part is worked out the summary of active compounds including their effects in cosmetics and within medical use. In the experimental part were determined certain metabolites of hemp products, while as samples were used hemp flower, leaf, seed, flour, protein and two different hemp oils. There were also prepared creams with the addition of hemp oil in which the effects on the skin were assessed. In the analyzed samples was according to the character of the material determined the content of antioxidants, saccharides, proteins, lipids including the profile of fatty acids, vitamins and chlorophylls. It was proved that hemp flower is a better antioxidant than the leaf and contains higher amounts of all of the determined active compounds with this effect. Flour and protein which are made from the seeds have different percentages of individual studied compounds, because there is a different process for their production. The highest amount of saccharides is in the flour, hemp protein preparative consists of a 50 % of protein and in the seed was the highest lipid content. In the prepared hemp creams the moisturizing effects and the ability to prevent transepidermal water loss were observed.
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Study of antimicrobial substances of ginger
Ciburová, Alena ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
For thousands of years ginger rhizomes are used in traditional Chinese medicine. Because of his significant pungent flavour is commonly used in foods and beverages all over the world. Nowadays many of the beneficial pharmacological positive effects of ginger rhizomes are identified. Their occurrence is due to the high concentration of bioactive compounds. This thesis is focused on analysing of occurrence of bioactive compounds such as polyphenols and flavonoids and their influence on antioxidation and antimicrobial properties of samples of fresh and dried ginger. The results show that for extraction of bioactive compounds in different ginger samples is more suitable to use different types of extraction solvents. The highest antioxidation activity was measured for macerate of 100% bio ginger tea from Sonnentor company in 96% ethanol. Antimicrobial properties were showed only for 100% bio ginger tea against gram-positive bacteria Microccocus luteus.
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Preparation of food supplement containing probiotic bacteria and components with anti-inflammatory effect
Horňáková, Nikola ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The presented thesis discusses the issues of chronic inflammatory diseases of the digestive system and suggests the possibility of the alternative natural remedies improving the health conditions or prolonging the remission phase of IBD. The main goal is to design a probiotic supplement enriched by natural anti-inflammatory agents. Phytochemicals, concretely phenolic compounds, flavonoids, and carotenoids suppress harmful inflammatory processes by direct targeting the function of the immune cells or by inhibiting damaging oxidative stress in general. Therefore, there were several plants potentially rich for these biologically active substances selected. Concretely, blueberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), turmeric (Curcuma longa), peppermint (Mentha piperita), chamomile (Matricaria recutita), cinnamon (Cinnamomum zeylanicum), ginger (Zingiber officinale) and flax (Linum usitatissimum). The suitable parts of these plants were extracted by using a total of three different solvents – water, ethanol, and hexane for obtaining lipidic extracts. The concentration of total polyphenols, total flavonoids, total carotenoids, and the ascertainment of specific polyphenols was determined in the prepared extracts. These characteristics were enhanced by the measurement of antioxidant activity of the aqueous and ethanolic extracts. The interaction of individual samples with probiotic cultures (Bifidobacterium breve, Lactobacillus acidophilus) and the ability of extracts to influence the viability of probiotics in the model digestion process has been examined. The most interesting samples (aqueous extracts of blueberries, mint, chamomile, and cinnamon) were selected for further experiments. The possible cytotoxicity towards human intestinal epithelial cells was tested in vitro by the MTT tests utilizing the CaCo-2 cell line. Extracts showing the highest levels of beneficial phytochemicals and antioxidant activity, supporting the growth of probiotic cultures, and showing minimal cytotoxic effects on human intestinal cells were then co-encapsulated with probiotics into alginate particles of a diameter of 1 mm. Water extracts of mint, chamomile, and cinnamon have been chosen. The encapsulation efficiency of successfully entrapped probiotics and phenolic compounds was determined in prepared particles. Furthermore, the particles were studied during the process of model digestion, when the release of the desired substances in the various parts of the digestive system was observed and assessed whether the components would reach the crucial point of action – the colon. For the use of the proposed probiotic mixture as a dietary supplement, a recommended dose of 1 g has been determined. Lastly, possible adjustments such as lyophilization or sheathing by an extra protective polymerous layer, e.g. chitosan, were suggested to prolong the shelf life of the particles and volatile substances stability.
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Cultivation of microalgae and carotenogenic yeasts under stress conditions
Sniegoňová, Pavlína ; Skoumalová, Petra (referee) ; Szotkowski, Martin (advisor)
In biotechnological industry we can register greater use of microorganisms like microalgae and carotenogenic yeast for production of selected substances or for valorisation of waste materials. Among metabolites produced by these microorganisms are carotenoids, which are natural pigments with antioxidant and other biological effects. Other significant produced substances are lipids, which represent large range of substances in living organisms. They form cellular membranes and serve as a reservoir of energy. These substances can be used in food, cosmetic and pharmaceutical industry and also in production of biofuels. Theoretical part is focused on description of selected genera of microorganisms, their cultivation and produced metabolites. Stress factors to which they were exposed are also mentioned, as are the analytical methods used for detection of produced metabolites. Next part is dedicated to the comparison of production properties of selected microorganisms depending on used stress factor. Increased production of lipids in yeast is observed in C. macerans and S. metroseus with higher concentrations of FeCl3. While using whey as a source of ccarbon, yeasts show decreased production of carotenoids. Highest production of lipids in algae and cyanobacteria was observed in S. acutus and D. quadricaudea. Production of carotenoids depended on applien stress factor and highest productions was observed in C. sorokiniana, C. reinhardtii, D quadricaudea and Coccomyxa sp.
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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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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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