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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.
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Preparation and characterization of nanodiamonds modified with biocompatible polymers
Kvaková, Klaudia ; Skoumalová, Petra (referee) ; Cígler, Petr (advisor)
Nanodiamanty (250 nm) boli podrobené oxidácií, a tiež separované podľa veľkosti. Následne bola na povrch nanodiamantov adsorbovaná rozvetvená vrstva polyglycerolu. Táto vrstva vzniká kyslo katalyzovanou ,,ring opening“ polymeráciou glycidolu s hydroxylovými a karboxylovými skupinami povrchu nanodiamantov. Vzniknutá polyglycerolová vrstva zvyšuje stabilitu a biokompatibilitu nanodiamantov. Po vytvorení polyglycerolovej vrstvy bol do reakcie pridaný glycidyl propargyl éter, čím došlo k terminácií polymerácie, v dôsledku zavedenia propargylu do reakcie. Prítomná trojná väzba umožňuje nové modifikácie povrchu, napr. prostredníctvom CuAAC reakcie. S využitím CuAAC reakcie je možné na povrch fluorescenčných nanodiamantov pripojiť manózu (so spojkou obsahujúcou azidoskupinu). Pripravené nanočastice boli charakterizované použitím fyzikálno chemických metód. Distribúcia veľkosti častíc bola meraná pomocou dynamického rozptylu svetla (DLS), a taktiež bola potvrdená obrazovou analýzou mikrografov z elektrónového transmisného mikroskopu (TEM). Vyhodnotené bolo aj správanie sa nanodiamantov v biologických podmienkach (stabilitné testy v 1xPBS, 10xPBS a 100 % FBS) a bol meraný aj zeta potenciál. Nakoniec boli pripravené fluorescenčné diamanty (250 nm) s naviazanou manózou. Vzhľadom k výsledkom termogravimetrie, meraniam DLS a pozorovania pomocou TEM môžeme povedať, pripravené nanodiamanty sú pokryté tenkou vrstvou polyglycerolu. Prítomnosť manózy bola zistená na základe FTIR spektier. Nami pripravené fluorescenčné nanodiamanty obalené vrstvou polyglycerolu sú vhodné pre ďalšie testovanie in vitro a in vivo vďaka ich stabilite v médiách s vysokým obsahom solí ako napr. fosfátový pufor (PBS) a nízkemu viazaniu proteínov vo fetalnom bovinnom sere (FBS).
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Study of natural compounds of elderberry flowers
Pončíková, Alžbeta ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
The aim of this bachelor thesis was to determine the concentration of bioactive substances such as polyphenols and flavonoids and also the total antioxidant capacity in extracts from flowers of elder. The second part was the subject of an experiment to determine the antimicrobial activity. The theoretical part deals with the description of individual bioactive substances, the description of the elder and the bacteria used. In the experimental part, aqueous extracts were prepared, in which total polyphenols, flavonoids and oxidizing activity were determined. The results of the determination of polyphenols and flavonoids show that in order to achieve a higher content of flavonoids and polyphenols, it is more appropriate to use the highest possible initial temperature for leaching the base flower. No significant differences were found when comparing the antioxidant activity of solutions from the average values. The extracts did not show significant antimicrobial activity.
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Isolation and characterization of natural antimycotics and their potential applications
Dvořáková, Eva ; Hoová, Julie (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis was focused on preparation and characterization of products containing natural antimycotic ingredients. The theoretical part summarizes the current issue of increased presence of mycoses and yeast diseases in connection with the extension of the problem of reduced immunity. Furthermore, the problem of synthetic drugs and antimycotics compared to alternatives of natural origin was described. In the experimental part, selected extracts (aqueous, ethanolic and lipidic) were prepared, characterized and subsequently encapsulated into liposomes. The content of polyphenols, flavonoids and the total antioxidant activity of extracts was measured. In liposomes, the encapsulation efficiency, size, stability and long-term stability were measured. In addition, the antimycotic activity of individual extracts and liposomes against Candida glabrata was studied. For comparison, the antifungal activity of the commercial drug clotrimazole was also tested. Lipidic extracts showed highest antimycotic activity from all of the prepared extracts, which is why these extracts were used to prepare antifungal gels and suppositories. More specifically, lipidic extracts of nasturcium, cinnamon, ginger and liposomes containing them were used. Their antimycotic activity was also tested and confirmed for these preparations. Finally, the cytotoxicity test on the HaCaT human cell line showed that used extracts and liposome particles are safe and that the prepared products could thus serve as an alternative to synthetically prepared antimycotics in the future.
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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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Probiotics for children's nutrition
Pokorná, Martina ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
This Diploma thesis deals with probiotic bacterias for children nutrition. It proposes a probiotic food supplement with a probiotic blend composed of a strain of the genus Lactobacillus and of the genus Bifidobacterium, which would be most suitable for infant consumers. The theoretical part is focused on probiotics, constitution of the children´s ganstrointestinal tract and screening of probiotic and gelatine supplements which are already sold on the market. In the experimental part, probiotic bacteria were subjected to model digestion, whereby mixtures of strains having the lowest reduction in viability after digestion were blend based on the results. The blend of Bifidobacterium breve CCM 7825T, Bifidobacterium longum CCM 4990 and Lactobacillus casei CCM 4798 was chosen as the most suitable blend of the lowest viability reduction. PCR in real time was demonstrated the presence of all strains added to the blend after model digestion. Finally, from the data was suggested a more comprehensive probiotic food supplement in the form of an alginate-agar gummy-bear for children over three years of age. The probiotic food supplement was subjected to sensory analysis too. The proposed probiotic food supplement also contained Chlorella and Spirulina active compounds and higher content of omega 3 and 6 fatty acids in hemp oil.
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Use and application of natural antimicrobial substances
Dzurická, Lucia ; Byrtusová, Dana (referee) ; Skoumalová, Petra (advisor)
The presented bachelor thesis is focused on the study of antimicrobial activity of plant substances in combination with bacteriocins and the possibility of creating new encapsulated form of supplement which could be used in food and cosmetic products. 5 plant materials were selected: acerola, cinnamon, cloves, orange peel and yacon syrup. Nisin was chosen as the most suitable bacteriocin. In the theoretical part the components with antimicrobial and antioxidant activity are described, such as the materials of plants and animal origin used in this work. Also the possibility of increasing the antimicrobial effect and possible use of natural antimicrobial substances were described. In experimental part, the aqueous extracts of selected plant materials were firstly spectrophotometrically characterized for the content of total polyphenols, flavonoids and antioxidants. Selected substances were encapsulated into liposomes and subsequently preparation of liposomes coated with chitosan was optimized. The particles were tested for size, short and long term stability, encapsulation efficiency and antioxidant activity. Furthermore, the antimicrobial activities of selected components in nonencapsulated and encapsulated form were observed against four strains of microorganisms (Escherichia coli, Micrococcus luteus, Serratia marcescens and Candida glabrata). Also the expected synergisms of the antimicrobial effects of extracts in combination with nisin and prepared particles were observed.
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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.
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Analysis of active substances contained in lavender and thyme extracts
Vašíčková, Milada ; Vysoká, Marie (referee) ; Skoumalová, Petra (advisor)
The presented bachelor thesis is focued on active substances contained in lavandula officinalis and common thyme extracts, mainly their possible antimicrobial and antioxidant effects. The theoretical part desrcibes chosen plants, compounds with antimicrobial and antioxidant effects, methods how to obtain and identify said compounds. In the experimental part, aquenous, ethanolic and oil extracts were prepared. Mentioned extracts were spectrophotometrically characterised for total content of polyphenols, total content of flavonoids and antioxidant activity. In conclusion possible applications of extracts in food industry instead of synthetic preservatives and their fotification were discussed.
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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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