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Characterization of some natural substances with antimycotic effect
Plachá, Monika ; Hlaváček, Viliam (referee) ; Márová, Ivana (advisor)
The introduced bachelor thesis is focused on investigation of the effects of natural substances with potential antimycotic effects and characterization of their constituents. As a part of this work, an overview of mycosis, antimycotics and constituents of natural substances were introduced. Moreover, antifungal susceptibility and genus Candida were described. In the end of the theoretical part the liposomes and their characterization were described. In the experimental part general characteristics of some natural substances and antimycotic test were analyzed. Aqueous, ethanol, methanol and DMSO extracts were tested on yeast strain Candida glabrata. Aqueous extract of the cloves, cloves oil and their combination were encapsulated into liposomes. The encapsulation effectivity, long-term stability and their antifungal activity were determined too. Characterization of liposomes was identified by DLS. Finally, application of liposomes to a preparation of pharmaceutical and cosmetic preparations were presented.
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Characterization of edible films with the potential usage in food packaging
Jančíková, Simona ; Vítová, Eva (referee) ; Veselá, Mária (advisor)
In the last years, the edible packaging has been gaining popularity due to the potential usage as the packaging for food instead of synthetic materials. The edible packaging can positively affect the packaged food by the active properties or due to its intelligent properties can monitor the changes in food. In theory, the legislation about the packaging of food and edible packaging was described. The substances for edible films preparation and additives, which can improve the properties of the edible films, were described too. In this part, the undesirable microorganisms occur in food and the chapters about active and intelligent properties of the edible films were summarized. The main aim of the thesis was the practical preparation of edible packaging/films made from furcellaran, gelatin hydrolysate with the addition of water dried or fresh rosemary extracts in concentrations 5 %, 10 %, and 20 %. In the experimental part, the physical analysis was done – textural parameters such as tensile strength and elongation at break, water content, and thickness. In the chemical analysis the total polyphenols content, determination of polyphenols by HPLC, antioxidant activity, optical properties and antimicrobial activity of the prepared edible films were done. There were found out, that the total polyphenols content and antioxidant activity were the highest in the 20%DR (TPC: 6,79 ± 0,06 mg gallic acid/g; DPPH: 87,84 ± 0,07 %). Also, the 20%DR and 20%FR changed color in different pH (3 and 12). The antimicrobial activity was negative. The thesis showed that the addition of natural extracts to edible films can increase the polyphenols content and they can also work as the UV protector.
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The ecological grape and wine production
Kalábová, Jana ; Pořízka, Jaromír (referee) ; Omelková, Jiřina (advisor)
Bachelor´s thesis is focused on technological processes of production of wine and now very mature producing organic wines. It describes the principles of organic farming and organic way of growing grapes. It provides basic information about grape wine, which is an important raw material for wine production. It refers also to the modern protection of ecologically grown plants from fungal diseases and pests. The aim of experimental part was to examine the effects of aqueous extract of dried sage to the growth of microorganisms. Sage contains protective substances effective in preventing of pests. The results showed, that the extract from the stems showed inhibitory effect on some selected microorganisms, but the extract from the leaves did not show inhibition.
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Smart food polymer layers
Valíková, Michaela ; Kovalčík, Adriána (referee) ; Veselá, Mária (advisor)
Smart packaging represents a group of packaging with great potential when used in the food industry. Active packaging can have a positive effect on the condition of stored food and smart packaging can inform consumers about the condition of stored food. In the theoretical part, a search was made on the topic of packaging in the food industry, with emphasis on active and intelligent packaging, including the legislative framework. The substances from which smart packaging is made have been described. In the experimental part, partially water¬insoluble polymer layers were prepared from gelatin, glycerol, crosslinking agent and anthocyanin extract. Glutaraldehyde or tannic acid was used as a crosslinking agent. Anthocyanins were obtained by extraction from red cabbage. The total concentration of anthocyanins in the extract was determined by the difference method. For prepared layers, their water solubility was measured and the colour response to the pH environment was evaluated spectrophotometrically. The stability of the layers over time was also monitored. It was found that the prepared layers are able respond to changes in pH.
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Dependence of quality parameters of malt on the temperature of mashing at sweet wort preparation
Zlámalová, Petra ; Sachambula, Lenka (referee) ; Mikulíková, Renata (advisor)
The Masters thesis deals with dependence of quality parameters of malt on the temperature of mashing at sweet wort preparation. The theoretical part focuses on the technology of malt production including description of ingredients, production parts, some kinds of malt and the quality parameters. There is also described the technology of sweet wort preparation and the methods of determination of the malt quality parameters in the sweet wort there. The experimental part focuses on determination of malt extract, viscosity, haze, colour, time of starch cleavage, pH, degree of fermentation and beta-glucans content. Based on temperature dependence of parameters, the individual samples were compared and the effects of temperature were discussed. The biggest extract of light and caramel malts was explored at 70 °C, of coloured malt at 50 °C. The lowest viscosity of light and coloured malts was explored at 65 °C, of caramel malt at 50 °C. The lowest haze of wort was at 65 °C. Ideal colour of all malts was at all mashing temperatures. Ideal pH of all malts was explored at 70 °C. Ideal time of starch cleavage was explored at 70-85 °C. The biggest achievable degree of fermentation and the hugest increase of beta-glucans content were explored at 65 °C.
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Analysis of sensorially active substances contained herbal extracts
Koloničná, Markéta ; Vítová, Eva (referee) ; Mikulíková, Renata (advisor)
The peppermint (Mentha piperita), the salvia (Salvia officinalis), the lemon balm (Melissa oficinalis), the camomile (Matricaria chamomilla) and the valerian (Valeriana officinalis) are herbs with healing effects. Their ethanol extracts are used for food fortification or in a cosmetic industry. Substances contained in herbal extracts were analyzed in this thesis. The extracts were prepared by maceration. Next, they were analyzed by using a gas chromatography and a mass spectrometry. The aim of this thesis was an optimalization of the method used for the analysis of sensorially active substances. Then, herbal extracts were analyzed and concentration of sensorially active substances was determined.
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Extraction of antioxidants from the elderberry blossom and preservation of the extract for further possible use
Krůzová, Sabina ; Němcová, Andrea (referee) ; Vespalcová, Milena (advisor)
The thesis deals with the extraction of antioxidants from elder flowers and the way of storage obtained extract. The elder flowers which are obtained by cutting trees as a waste product and after their processing it could be used as an ingredient to cosmetics products for body and face skin or in a spa like additive to baths. In theoretical part are information about black elder, its botanical characteristics, utilization and about substances contained in it. There is also a chapter about lyophilization as a method which was used for concentration of extract. The last chapter describes theoretical information about liquid chromatography because this method was used for analysis of contents of extract. Experimental part describes optimalization steps in preparation of extract. It was found that the biggest content of polyphenolic compounds was when the proportion between flower and water was 1:10, optimal temperature of water for extraction is 100 °C and it was also found that the time of extraction don´t have any influence on content of polyphenols. Thanks to the lyophilization it was obtained dry light brown powder which is stable for long time. The lyophilizate was tested for some physical properties like pH, refractive index, solubility etc. There was also determined antioxidant activity by DPPH method and there was found quenching activity is 64,9 %. In determining of heavy metals in sample was found trace amounts of lead and chrome. By liquid chromatography was determined content of polyphenols, caffeic acid was in an amount 59,6 mgl1, chlorogenic acid 398 mgl1 and ferulic acid wasn´t detected. All of analysis was for 1% solution of extract because to cosmetic it could be just this amount to addition. In the last step was prepared a skin lotion with elder flower extract and it was tested for stability also was prepared an ointment from pork lard.
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Determination of volatile substances of natural extracts intended for cosmetic application
Paskevych, Olha ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Tato bakalářská práce je soustředěná na zkoumaní přírodních komerčně dostupných extraktů, které se používají do přírodní kosmetiky. Literární rešerše byla zaměřena na téma obsahu těkavých látek v přírodních extraktech používaných v kosmetice, jejich charakterizace a možnosti stanovení, problematika výskytu alergenů v přírodní kosmetice. Na základě tohoto přehledu byla navržena optimální metoda pro analýzu vzorků přírodních extraktů s přihlédnutím k dostupné analytické instrumentaci. Následující výtažky byly studovány se zaměřením na kvalitativní stanovení: mandle, aloe vera, hřebíček, Etiopská káva, zázvor, cibule.
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Monitoring of the selected parameters of grape wine before expedition
Trávníčková, Jiřina ; Pořízka, Jaromír (referee) ; Omelková, Jiřina (advisor)
Presented bachelor thesis is focused on laboratory monitoring and determination of the selected parameters of grape wine which includes specific gravity, alcoholic content, reducing sugar content, total titratable acidity, volatile acidity and total solids, sulfur dioxide content and protein and crystalline wine stability. The theoretical part deals with the wine production technology from the entry commodities to the bottling of mature wine. The aim of experimental part is a description of analytical determinations and complete wine sample analysis according to Regulation EEC No 2676/90 determining Community methods for the analysis of wines.
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Basic features of wine fermented from freerun and pressed must
Becková, Eliška ; Šalplachta, Jan (referee) ; Vespalcová, Milena (advisor)
My work is engaging in winemaking of white and red wines. Theoretic processes and goings during winemaking is describe in the first part of this work. It deals harvest of kapes, fermetation, clearing wine, chemical content of grapes and wine, deseases and abnormality of wines. There are this described choosen variettes, their grapes were processed practically. The third part of this work is dealed in practice winemaking and chemical analyse sof wines. Musts from the start of pressing, from the first dressing and from the end dressing fermented to the end dressing . They were fermented and than analysed by chemical and tasting tests. The discussion about the dependence of the quality of wines on the kind of the must during pressing is presented in the end of this work. The results are motivated by chemical analyses and senzoric tasting of the experts.
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