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Microfauna of the activated silt from the biological sewage disposal plant in Kroměříž region.
Hrudíková, Radka ; Illková, Kateřina (referee) ; Omelková, Jiřina (advisor)
Bachelor thesis deals with the description and evaluation of micro fauna of activated sludge biological sewage waste water in Kromeriz region. Furthermore, morphological description and evaluation of sludge flocs. The thesis describes the types of biota (biocenosis), which may occur in the activation tanks. There are also mentioned other incidental methods of sewage treatment such as mechanical, chemical and physicochemical methods. The experimental section describes the experiment procedure, apparatus and methods use for assessment of activated sludge. In the results the data are processed into the synoptic charts and the accompanying tables. At the end the results are evaluated.
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Monitoring of Phytoestrogens Expression to the Milk and Milk Products
Watzková, Jarmila ; Rittich, Bohuslav (referee) ; Doležal, Petr (referee) ; Omelková, Jiřina (advisor)
Phytoestrogens are very intensively studied in recent years because they show different pharmacological effects on human health. For example, it was demonstrated that phytoestrogens reduce the risk of certain cancers (breast, prostate or colon), act as antioxidants in the body and affect the activity of certain enzymes. In addition, also it was demonstrated number of positive effects of soybean phytoestrogens on the health status of women in the menopause, such as reducing the risk of atherosclerotic cardiovascular disease or osteoporosis. Various technologically processed soy beans are important part of the feed rations mainly for high-lactating dairy cows, because they are a valuable source of the energy and high-quality protein, despite their negative effect on reproductive performance. Phytoestrogens consumed from the feed rations are hydrolyzed in the rumen of dairy cow and together with their metabolites are absorbed in the small intestine into the blood. They can be excreted from the body in urine or milk. From this perspective, cow's milk may become a source of phytoestrogens substances, especially equol in the human nutrition. On the other hand, some research results suggest possible potential risks associated with phytoestrogens intake in the diet on human health. At the some age (infants and young children) and group (vegetarians) categories may be dietary intake of phytoestrogens undiserable. According to most experts, a beneficial effect on human health prevail the potential risks. However, the risks associated with phytoestrogens intake in food can not be ignored and therefore phytoestrogens are still actual problem in the field of scientific research.
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Impact of elevated carbon dioxide concentration on protein content of gliadin fraction in winter wheat
Hamříková, Dominika ; Omelková, Jiřina (referee) ; Hrstka, Miroslav (advisor)
In this diploma thesis protein content of gliadin fractions in winter wheat (Triticum aestivum) var. Bohemia was studied. The crop was cultivated in conditions with ambient (AC) and elevated (EC; 700 mol•mol-1) carbon dioxide concentration. Moreover, half of the samples was fertilized with nitrogen in an amount of 200 kg•ha-1. Other observed environmental factors were drought and UV radiation. The gliadin proteins were separated by A PAGE method and quantified by computer densitometry. Generally the protein content within , and gliadin fractions varied, while the protein content of gliadins remained unchanged or almost unchanged. Clearly the nitrogen fertilization had the most pronounced impact on the gliadin protein content and it significantly increased the protein content in wheat grain. Most subfractions reacted in conditions of AC, drought and without UV radiation and in conditions of EC with natural rainfall and UV radiation. The interaction of nitrogen fertilization with UV radiation (AC, drought) was significant and so was the interaction of nitrogen fertilization excluding UV radiation (EC, drought). The interaction of nitrogen fertilization and natural rainfall significantly increased the protein content in conditions of AC without UV radiation and in conditions of EC with UV radiation. EC alone and the interaction of EC with other factors had only a small impact. The impact was the most pronounced in interaction with nitrogen fertilization. EC with nitrogen fertilization (drought without UV radiation) increased the gliadin protein content and EC excluding nitrogen fertilization (drought and natural rainfall with UV radiation) decreased the protein content.
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Utilization of plant origin waste
Habáníková, Kamila ; Flodrová, Dana (referee) ; Omelková, Jiřina (advisor)
Production of cellulase and polygalacturonase by Aspergillus niger and Aureobasidium pullulans was studied in submerged (SmF) and solid state fermentation (SSF) systems. Substrates used in fermentation systems were mandarin peels and grape pomace. With Aspergillus niger used on grape pomace as a sole carbon source, cellulase production was detected after 72 hours in SSF and after 24 hours in SmF systems. The activity of cellulase per gram of substrate was higher in a submerged than in a solid state fermentation system. The longer time for higher polygalacturonase production was necessary in submerged fermentation systems and polygalacturonase activity was higher in SmF. The SSF fermentation with mandarin peels as a sole carbon source was similar, the highest detected activity of cellulase was determined after 72 hours. Different production of polygalacturonase was observed on mandarin peels in SmF systems. A comparison of enzyme productivities on grape pomace and mandarin peels showed that polygalacturonase activity per gram of substrate is highest in SmF system with mandarin peels as a sole carbon source. With Aureobasidium pullulans used on grape pomace as a sole carbon source, cellulase production was detected after 48 hours in SmF and SSF fermentation systems. The activity of cellulase per gram of substrate was higher in solid state system than in a submerged fermentation system. Longer time for higher polygalacturonase production was necessary in both fermentation systems. Polygalacturonase activity was higher in SmF. The SSF fermentation with mandarin peels as a sole carbon source was similar, the highest detected activity of cellulase was determined after 48 hours. Different production of polygalacturonase was observed on mandarin peels in SmF systems. A comparison of enzyme productivities on grape pomace and mandarin peels showed that polygalacturonase activity per gram of substrate is highest in SmF system with mandarin peels as a sole carbon source. For both systems and both substrates manganese-dependent peroxidase was detected for the first time. Differences in the enzyme synthesis by Aspergillus niger and Aureobasidium pullulans depend on both the substrates used as well as on the fermentation system.
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Properties and production of microbial lipases
Martinková, Patrícia ; Reichstädter, Marek (referee) ; Omelková, Jiřina (advisor)
Bachelor´s thesis is focused on testing the culture media for growing various strains of yeasts, producing lipolytic enzymes and to study the influence of culture media composition on the production of lipolytic enzymes. Theoretical part of this thesis states the characteristics of lipolytic enzymes, their properties, sources, conditions for their production and the possibilities of their application. Together 8 strains of yeasts were used in the experimental part of the thesis, namely 2 strains of Yarrowia lipolytica, 2 strains of Kluyveromyces lactis, Cryptococcus saitoi, Candida intermedia, Candida oleophila and Debaryomyces hansenii, which were cultivated on 4 media with different compounds. During the cultivation the growth of biomass was monitored and growth curves were formed based on these results. Selected strains of yeasts were tested during the process of cultivation for lipolytic activity of two types of enzymes – enzymes bonded to the cellular structure and extracellular enzymes, which were measured by spectrophotometer. Production of lipolytic enzymes varied depending on applied culture medium.
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Fragrance Allergens in Foods and Everyday Use Products
Divišová, Radka ; Buňka, František (referee) ; Hojerova,, Jarmila (referee) ; Omelková, Jiřina (advisor)
Fragrances are added to food, cosmetics and other products primarily for enhancement of their sensory quality (taste and/or aroma). However, the usage of these compounds is associated with the wide range of various adverse biological effects. Some fragrances widely used in cosmetics are proved to cause e.g. skin sensitization, rashes, dermatitis, headache, cough etc. To protect the health of consumers, European union approved the cosmetic directive (ES/1223/2009) that requires the labeling of 26 allergen fragrances on the final product label, if concentration exceeds the given level (0,01 % for rinse-off and 0,001 % for leave-on product). However, some producers hide the presence of allergens in the final product under the general term „aroma“. For this reason it is very important to monitor the content of these substances in cosmetic products. Fragrances are found not only in cosmetics, but the various types of food are also aromatized by them. Unlike cosmetics, the food producers are not obliged to label the presence of fragrance allergens on the packaging. Therefore, the monitoring of these fragrances is highly desirable because of the potential health risks they pose. The aim of this study was to develop a method for simultaneous determination of regulated fragrance allergens in food and everyday use products. The method based on extraction of analytes by solid phase microextraction coupled to gas chromatography with FID detection (HS-SPME-GC-FID) was chosen on the basis of the literature review. The fiber CAR/PDMS provided the highest extraction efficiency among the SPME fibers tested. Univariate and multivariate data analysis were used to optimize the main parameters affecting microextraction process. The final method validation was performed in terms of linearity, repeatability, reproducibility, recovery, limits of detection and quantification. The optimized and validated method was applied to a wide range of products including cosmetics, aromatized food and fragranced toys. These products were also subjected to sensory evaluation especially in terms of taste and/or aroma (i.e. flavour), which may be associated with the content of the monitored fragrances. The profile test (EN ISO 13299) and seven-point category ordinal scale (ISO 4121) were used for sensory evaluation.
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Factors influencing the quality of red wine
Zechmeisterová, Lucie ; Vránová, Dana (referee) ; Omelková, Jiřina (advisor)
In my thesis, I focused on monitoring of microorganisms in the sample of red grape juice and on the interactions between yeasts, bacteria and filamentous fungi. Three different media were applied for the cultivation of microorganisms; firstly for monitoring of total volume of microorganisms, secondly for yeasts and third time for lactic acid bacteria. The indirect method was used for the determination of the amount of viable cells. This method consists in enumerating of visible macroscopic colonies grown up on agar plates. When the cells grew up, the forms of colonies were analyzed visually and the morphology of microorganisms was detected microscopically. The operating time of enzymes in grape juice in the production of red wine was monitored after application of commercial enzymatic preparation. The enzym action in grape juice was observed on the basis of the process of degradation of high – molecular substrate by enzymes through the use of Ubbelohd´s viscometer. The research findings provided a lot of knowledge about the occurance of microflora in the process of production of red wine. The commercial preparations added to grape juice played a significant role.
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Study of lipase production using selected microorganisms
Rošková, Hana ; Babák, Libor (referee) ; Omelková, Jiřina (advisor)
Diploma thesis was aimed at studying of lipolytic activity of seven microorganisms, at which this activity was previously assumed or already confirmed. Theoretical part deals with the general characteristics of lipoyltic enzymes, specifics of microbial lipases and their industrial application, with an emphasis on food industry. Experimental part deals with the study of seven microorganisms and their lipolytic activity at the presence of a carbohydrate (glucose) or a lipid (canola oil) or both, as a source of carbon. For further testing were singled out Rhodotorula minuta nad Yarrowia lipolytica. This yeasts were subsequently tested for lipolytic aktivity at the presence of different vegetable oils (olive, sunflower, canola oil and waste cooking oil), nitrogen sources of organic and inorganic origin (urea, yeast extract, amonnium chloride, amonnium sulfate) and also a addition of detergent, which is commonly used in food industry or other food facilities.
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