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Preparation and application of PHA based nanofibres and nanoparticles
Linha, Vojtěch ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
The goal of this thesis was to summarize basic options of fiber spinning and manufacturing and their usability in industry. Methods of nanofiber spinning are described in the teoretical part, alongside the materials used in experimental part. The experimental part was focused on creating of workflow of defined nanofibers in laboratory enviroment, the possible modification of nanofibers with aditives. The release of aditives from different nanofibers into different enviroments was measured.
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Characterization and application of some plant antimicrobial substances
Bendová, Agáta ; Bokrová, Jitka (referee) ; Skoumalová, Petra (advisor)
The main goal of this bachelor thesis was the study of antioxidant and antibacterial effects of natural plant extracts and liposomes. The theoretical part was focused on description of natural antimicrobial and antioxidant substances from selected herbs and spices. Also bacterial resistance and methods used in work were described. In the experimental part basic characteristics of extracts from 12 kinds of herbs and spices (oil, alcohol and aqueous) were analyzed. Mainly content of polyphenols, flavonoids and the total antioxidant activity were determined. All extracts were also encapsulated into liposomes and the encapsulation effectivity, long-term stability and size and stability of liposomes were determined. The size of prepared liposomes was in range of 100 nm to 200 nm. Stability of the liposome particles was measured using a zeta potential and all prepared particles exhibited very good stability, but in term of long term stability were liposomes relatively unstable. Antibacterial activity was tested against Gram-positive Micrococcus luteus and Gram-negative Serratia marcescens. Encapsulation of extracts into liposome particles has greatly increased their antimicrobial effect and liposomes containing oil extracts from the goat, nutmeg and pepper and liposomes containing alcoholic extracts from star anise and cloves were the most effective against both strains. The prepared liposomes could be used as alternative to antibiotics and could be found application in the form of various antimicrobial gels for the cosmetic or pharmaceutical industry.
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Potential microbial hazards in actual cosmetology trends - bio, vegan, raw
Jančíková, Simona ; Skoumalová, Petra (referee) ; Němcová, Andrea (advisor)
Bio-, vegan- and raw-cosmetics are continually more popular type of cosmetic products caused by an absence of synthetic and preservative substances but at the same time there is an increased probability of microbial contamination. The main aim of this thesis is a practical findings of potential microbiological contamination using a challenge test and a determination of any active ingredients in the cosmetic preparations. The legislation of cosmetic preparations as well as the information about certificates, which are awarded for bio-, vegan- and raw-cosmetics has been processed in the theory. This section also discusses a composition of vegetable and essential oils, which are used as raw materials in cosmetics production to a great extent and have a positive effect on skin. This thesis also deals with a possible microbiological contamination, listing the most frequently occurred pathogenic microorganisms, which can have a negative influence on consumer health. Operating life of selected samples using the Schülke Koko test by inoculating selected representatives of bacteria, yeasts and molds (Candida glabrata, Escherichia coli, Pseudomonas aeruginosa and Aspergillus niger) are being tested in the practical part. In addition a possible antimicrobial activity which may partially replace an effect of synthetic preservatives in the presence of essential oils is also being tested. Finally any biological active substances were analysed by the gas chromatography, in particular fatty acids contained in the creams.
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Influence of disinfectants on the content of lactic acid in the production of refined sugar
Novotná, Hedvika ; Skoumalová, Petra (referee) ; Horák, Radek (advisor)
The diploma thesis compares the effectiveness of disinfectants on the content of the lactic acid. The disinfectants used for the experimental part are formalin and BetaStab®. The content of glucose and lactic acid was observed and compared after processing conventional beet and bio-beet. Based on the analysis of the measured data, it was found that the highest disinfecting effect on the lactic acid content had formalin, the avearge lactic acid value was 275 mg/l. In experiment with BetaStab® disinfection the average value of the lactic acid was 350 mg/l. When the beet was processed without the use of disinfection, this average lactic acid was 371 mg/l and in the untreated treatment of the bio-beet, the lactic acid content was 467 mg/l. The glucose content of formalin disinfection diffusion juice reached an average of 573 mg/l. When BetaStab® disinfection was applied, the average glucose content was 348 mg/l and a similar value was measured for the bio-beet treatment (328 mg/l). The highest glucose content had untreated conventional beet, where an average value of 690 mg/l was reached.
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Study of rose hip bioactive compounds
Konderla, Patrik ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
Purpose of this thesis was research the content of biologically active substances in herbal rosehip extracts and also determination of antimicrobial and antioxidant activity of these extracts. Teoretical part describes informations about Rosa canina L., detailed specification of biologically active substances, specification of antioxidation and overview of methods determine antioxidant compound and antimicrobial activity. In the practical part was by combination of different solvents, procedures and herbal materials, made 21 extracts of Rosa canina L.. From measuring of these extracts, was made extraction curves and also was determined antimicrobial efficiency against bacterial strains Serratia marcescesns, Bacillus subtilis, Bacillus cereus and Micrococcus luteus. Results shows, that also all extracts has some antimicrobial activity, but only against microorganisms Micrococcus luteus and Bacillus cereus. Also was found that bud extracts contains more bioactive compounds soluble in ethanol, meanwhile rose hip extracts contains more bioactive compounds soluble in water.
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Biological effects of various hemp fractions
Vacková, Hana ; Skoumalová, Petra (referee) ; Němcová, Andrea (advisor)
Cannabis is the only plant which contains cannabinoids and thanks to these compounds it has enormous potential. This thesis deals with the analysis of technical hemp. Effects of cannabinoids and methods used for cannabis analysis are discussed in the theoretical part. The experimental part includes spectrophotometric characterization of cannabis, it´s antimicrobial effects and thin layer chromatography analysis. Three sorts of Cannabis sativa L. were analyzed, namely Finola, Fedora and Kompolti. Firstly, the content of polyphenols, flavonoids and antioxidant activity in prepared tinctures were determined. Moreover, antimicrobial test were performed using disk test and turbidity determination. Gram-positive and Gram-negative bacteria and yeast organism were tested. It was found that cannabis tinctures possess good antimicrobial effects. Some of them are comparable with synthetic antibiotics. Finally, thin layer chromatography enabled visualization of cannabinoids in prepared tinctures.
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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 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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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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Diagnostics and Therapy of the Hallux Valgus - Experimental Study
Skoumalová, Petra ; Veverková, Michaela (advisor) ; Helcl, František (referee)
Název práce: Problematika diagnostiky a terapie hallux valgus- experimentální práce Title ofwork: Diagnostics and Therapy ofthe Hallux Valgus - Experimental Study Cíl práce: Cílem práce je posoudit, do jaké míry je možné ovlivnit hallux valgus osmitýdenním cvičením a zjištěné poznatky porovnat s výsledky kontrolní skupiny. Metoda: Vliv osmitýdenní terapie je hodnocen na základě klinického vyšetření, vyšetření nohou na podoskopu a Plantografu V05. Sledovanými veličinami jsou škály subjektivních obtíží, valgozita palce a distribuce plantámích tlaků. Zjištěné výsledky jsou porovnány s výsledky kontrolní skupiny. Výsledky: Práce shrnuje současné literární poznatky problematiky hallux valgus, možnosti diagnostiky i terapie. Představuje a hodnotí novou metodickou řadu cvičení vycházející z aktivace tříbodové opory nohy. Výsledky prokazují pokles valgozity palce vlivem použitého cvičení. Klíčová slova: hallux valgus, valgozita palce, plantámí tlaky, cvičení aktivace tříbodové opory nohy
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