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Biogenic amines in beer
Čiháková, Dagmar ; Orsák, Matyáš (advisor) ; Braný, Pavel (referee)
This thesis deals with the technological process of brewing beer, describes the raw materials needed for its production, and points out the useful and harmful substances contained in beer as biogenic amines (BA). Furthermore, there are described the issues of biogenic amines in food and primarily in beer, which is a histamine, putrescine, cadaverine, tyramine and tryptamine. In the practical section BA was determined in lager bottom-fermented beers from local microbreweries and large industrial breweries.
Beer is according to legislation considered as a safe food containing a variety of healthful nutrients such as B vitamins, proteins, carbohydrates, minerals, soluble fiber and polyphenolic merged, which have anticarcinogenic, antioxidant and antimicrobial effects. On the other hand, in beer we can find harmful substances such as alcohol, heavy metals, N-nitrosamines, aromatic hydrocarbons, polychlorinated biphenyls, nitrates and biogenic amines.
In the second part of the research are summarized the issues of BA in certain foods and beverages, their chemical structure, the way how they are created and their negative effects on the human body. BA are natural, biologically active substances that are essential for the human organism. Their excessive amount in beer is toxic for the human organism. Ethanol contained in the beer decreases the activity of the enzyme monoamine oxidase, and this leads to reduced degradation of BA. Intoxication of BA can cause headaches, vomiting, hypertension, allergic reactions, rashes and even loss of consciousness, therefore, should be the content of these substances monitored.
In the practical part of this theses the samples of bottom-fermented beers were analyzed. The first group of samples included unfiltred and unpsaterized beers from microbreweries. In the second group there were filtered and pasteurized beers from large breweries. HPLC determined BA in beer (histamine, putrescine, cadaverine, tyramine and tryptamine). The resulting values indicate that the domestic beers contain biogenic amines in very small concentrations, thus satisfy the legislative standarts. The results were also compared between the two groups of samples. These samples showed that the beer from microbreweries is not contaminated as originally was expected. It shows good technological processes in the manufacture of beer in such small devices.
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Antioxidant Activity of Wheat with Colored Grain
Míková, Marie ; Orsák, Matyáš (advisor) ; Varvažovská, Pavla (referee)
The Bachelor's Thesis covers the literary review about wheat in the context of antioxidation activity of its coloured varieties. The theoretical part deals with wheat and its properties, its origin, taxonomy, morphological structure and chemical composition.Furthermore, it studies the methods of getting antioxidation activity data - ABTS, DPPH and ORAC. The aim of the practical part is to compare the antioxidation activity of the chosen wheat samples either with the purple-coloured or blue-coloured grain, with the ordinary redcoloured wheat grain. The outcomes contributed to verification of the antioxidant-active substances in case of the wheat types with the typically red-coloured grain.
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Influence of cadmium on the content of selected elements in spring barley (Hordeum sativum L.)
Trsková, Nikol ; Orsák, Matyáš (advisor) ; Hnilička, František (referee)
The theoretical part of the thesis consists of research on the spring barley and chemical composition of its grains. Attention is paid to the stress factors which has inpact on plants such as heavy metals and in particular cadmium and its influence on the plants. The last part deals with the importance of selected trace elements such as copper, iron, manganese and zinc.
The experimental part of the work is devoted to the influence of cadmium contamination on content of selected elements which are copper, iron, manganese and zinc in plants of spring barley. Two experiments were performed. In both experiments, plants were hydroponically cultivated in Knop nutrient solution. Plants were divided into two parts in each experiment, the first part was cultivated without contamination and served as a control samples, the second part was contaminated. The third day of cultivation was added CdCl2.2,5 H2O at a concentration of 10-5 mol/l to the nutrient solution of the second part. In the first experiment the plants were harvested on the 10th day of cultivation and divided into roots, hypocotyls and shoots. In the second experiment were plants harvested on the 13th day of cultivation and separated into roots, hypocotyls, stem base, 1st (oldest), 2nd and 3th (youngest) leaf. From each part of the plant were prepared samples, which were mineralized and consequentely was measured using the ICP-OES method the content of the above mentioned metals in the contaminated and control-sample plants and the content of cadmium in the contaminated plants. The content of cadmium in the control-sample plants was measured by the ETA-AAS. The measured datae were analyzed and described in to the taps and graphs. Highest concentration of cadmiu was discovered in roots of the control sample plants, in case of the first experiment the roots contained 91 %, in the second 95,5 % from the entire amount of cadmium contained in the plant. As a result of the contamination changes in contents of the selected elements ocured. In both of the experimentes the amount of Cu in roots increased, in the upper part of the plants (shoots) the amount was lower comparing
non-contaminated plants. The iron content in the first experiment increased in roots and hypocotyl, in the upper part of the plants (shoots) the content decreased in comparison with control variant. In the second experiment, was the iron content lower in all plant parts. The manganese content was lower in the contaminated plants in almost all parts, only in the first experiment was found minimal increase of manganese content in roots. In both experimentes was found minimal change in content of zinc in roots, in the first experimente increased zinc content in hypocotyls and decreased in the upper part of the plants (shoots), while in the second experiment there was little change of content in hypocotyls but zinc increased in the upper part of the plants (shoots).
The deferences in results of both experimentes may be dependent on varions lenght of the cultivation.
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Toxic metals in foods
Klímová, Martina ; Orsák, Matyáš (advisor) ; Hniličková, Helena (referee)
Summary
Bachelor thesis Toxic metals in food is focused on toxic metals, their description, toxicity and monitoring their content in foods. Toxic metals significantly contaminate the environment nowadays. The metals pollute the environment through burning fossil fuels, agriculture and producing and processing of metals. They occur in various forms and appear in compounds, rocks and minerals. Their toxicity for human and animals is substantial. Their toxicity is related to the form of occurrence, solubility in water and in organic solvents and their mobility in body and water. Toxic metals bind on SH group of proteins and work as an enzyme poisons. The most toxic effect was found in cadmium, but also other metals have significant toxic effect. Lead, Cadmium and Arsenic have carcinogenic effects and cause malignant tumour. Mercury and above mentioned have mutagenic and teratogenic effects. Significant contamination of the environment and food can lead to poisoning, which is expressed by various symptoms.
Toxic metals are absorbed especially by inhalation and consumption of contaminated food. Agriculture crops are polluted from contaminated soil, water and using of fertilizers and pesticides. To meat and animal products, toxic metals come mainly from contaminated plants, which animals eat. Meat products can be polluted by incorrect technological procedure. In general are toxic metals cumulated by organisms in tissues, especially in kidneys and liver. Animals living in polluted area have a lot of these metals in their tissues. With its increasing age, cattle more accumulate toxic metals in its tissues, therefore maximum recommended age of slaughter is 3 years. Serious problem is high amount of mercury in fish, especially in the sea fish. The larger and more carnivorous the fish is, the more they cumulate mercury and the other metals. Especially in the contaminated sea, mainly polluted sea from oil, fish have more metals in tissues. Across the European Union, there were currently set strict limits on the contents of metals in food. Some limits were updated and added by the last findings last year. Keeping these limits is regularly checked.
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Natural compounds in foods with anti-cancer effects
Soukup, Josef ; Orsák, Matyáš (advisor) ; Hnilička, František (referee)
In this thesis, I focus on natural substances which are present in commonly available foods and their effects can not only considerably prevent, but also help treat cancer. As this is a very extensive topic, included are only substances which have been studied for this purpose for a long time and which have a large potential in this area. These are phenolic compounds, carotenoids, sulfur compounds, substances found in cruciferous vegetables or green tea, beta-glucans and their sources, and other health beneficial foods such as turmeric, ginger or garlic. I also mention several vitamins (C, E, A, D) which directly show anti-cancer effects or are used in combination with other means to increase the efficiency of the treatment. The deficiency of some other essential vitamins and minerals increase the risk of certain types of cancer as well and a large amount of anti-cancer acting compounds can be also found in herbs, exotic mushrooms, marine organisms and microorganisms, but that area exceeds the content of this thesis. Although nowdays there are substances targeted at only one symptom and can have a certain effect, these medicaments are associated with many side effects and are also expensive. The contemporary paradigm for cancer treatment is either combine several single-targeted medicaments or come up with medicaments that modulate multiple targets. Various types of cancer have similar character, but due to a different etiology of each type and different effect of individual anti-cancer substances (even belonging in the same chemical group), the efficiancy of these compounds against various types of cancer, mostly depending on metabolism, distribution in organism and the target use, differs significantly. Therefore, some substances can show a very strong anti-cancer effect at certain cancer types, while almost none at different types. Other factors such as biological availability or stability make utilization of many compounds more difficult. Basic types of anti-cancer effects are: antioxidant effects (the ability to scavenge free radicals), antiproliferative effects (the inhibition of uncontrolled growth), the ability to induce apoptosis (induction of programmed cell death), the ability to inhibit metastasis and anti-angiogenic effects (prevention of the formation of new blood vessels of the tumor).
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Analysis of Organic Acids in Wine
Cindrová, Kristina ; Orsák, Matyáš (advisor) ; Weitosch, Štěpán (referee)
Wine contains organic acids, which determine its final quality. Tartaric and malic acids are found in dominant concentrations. Also present are citric, lactic and succinic acids, and some volatile acids such as formic and acetic acid. The process of winemaking is associated with changes in the concentration of wine acids. The composition of acids in wine is also affected by the type, quality and ripeness of grapes, grape manufacture and wine production.
The aim of this study was to analyse the concentrations of tartaric, malic, citric, lactic, succinic, formic and acetic acid during the winemaking process in different press fractions of 8 varieties of white wines from the Vineyard centre Mělník - Chloumek and in 5 commercially purchased red wines, using HPLC with DAD detection, and to analyse the trend of changes in different phases of the winemaking process. The white wine press fractions were supplied following the wine press (A), settling of juice (B), in the phase of partially fermented juice (C) and during the maturation of young wine (D-G.). The samples were taken within 2-3 days. There were no red wine press fractions available from the vineyard. 5 bottles of different varieties of red wine were thus purchased from the shop and analysed. The GraphPad Prism programme was used to perform statistical analyses (ANOVA).
The hypothesis suggesting that tartaric acid would be the dominant acid was confirmed in 5 varieties of white wine and in all red wines.
The hypothesis suggesting a difference between red and white wines was also confirmed. There were significant differences in the concentration and composition of acids between young white wines and red wines.
The hypothesis that the concentration of all acids would increase was not confirmed. Tartaric acid showed the most linear trends of decrease, followed by malic acid. The trend of change in the concentrations of succinic, lactic, citric and formic acid increased in some varieties and it decreased in others.
The grape variety, weather during summer and autumn and the manufacturing processes all influence the acid composition in wine. These factors can explain the differences seen between different varieties of wine.
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Nootropics
Malík, Matěj ; Orsák, Matyáš (advisor) ; Hnilička, František (referee)
This bachelor thesis deals with the group of substances called nootropics, otherwise known as smart drugs. Nootropics are composed of a diverse group of medicinal substances, which, with their effect, enhance the abilities of human thinking, learning and memorising, especially in cases where these functions are in disorder. In essence and a certain sence, nootropics affect the metabolism of neuronal cells of the CNS. These smart drugs intensify the supply of glucose and oxygen into the brain, increase the synthesis of proteins and nucleic acids in neurons, and enhance the metabolism of phospholipids in neurohormonal membranes. Generally, the desired effect, however, arrives after a longer period of use.
In addition, this work describes the indication of these substances, possible treatments, and their use. Nootropics are divided into four groups: classic nootropic substances, substances increasing brain metabolism, cholinergics and plants with nootropic effect. For each of these groups, the best known members are described more in detail. For the last mentioned group, namely the group of plants with nootropic effect, their collection and processing of herbal drugs is described. Furthermore, the thesis focuses on suitable methods of assessment, mainly the so-called high-performance liquid chromatography technique, known under the abbreviation HPLC. Also mentioned are the legislative measures regarding these substances, such as Act No. 378/2007 Coll. on pharmaceuticals and amendments to some related laws, Decree No. 63/2007 Coll. on payments of pharmaceuticals and foods for special medical purposes, Decree No. 385/2007 Coll. on the establishment of the list of medical substances intended for supporting or additional treatment, and Decree No. 225/2008 Coll. which establishes the requirements for food supplements and food enrichment.
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