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The most important dietary sources of lipophilic vitamins
Šafránková, Simona ; Hejtmánková, Alena (advisor) ; Táborský, Jan (referee)
Basic piece of knowledge about nutrition and its need should be integral to every mans general knowledge. One of the vital nutritions ensuring a full-functioning organism are vitamins. Vitamins are essential ingredients, which play an important role in the human body and also in the processes of absorption and the exchange of substances between the external environment and living organism. They were discovered recently during the 20th century. The researches on their effects on the human body are still ongoing.
The vitamins are divided into two basic groups, water soluble vitamins, the so called hydrophilic (vitamins B and C), and fat soluble vitamins, the so called lipophilic (vitamins A, D, E and K).
The vitamin A is important to ensure good vision and recognizing colors. It support the quality and growth of bones, affects the egg and sperm and is needed for proper fetal development.
Vitamin A is found in foods of animal origin, such as dairy products, milk, meat and liver. In the food of plant origin, the vitamin A is replaced with many provitamins, of which most important is the beta carotene. A very rich source of these provitamins are leafy greens such as spinach or cabbage.
The recommended daily intake of vitamin A is 800 microgram, according to the standards of Czech republic. This need depends on the gender and age of each individual. The lack of vitamins A causes photophobia and impaired vision. The excess of vitamin A may be toxic for the organism. The interesting fact is that the beta carotene is not considered to be toxic.
Vitamin A is one of the labile vitamins. It is sensitive to heat, light and oxygen. At a gentle meal preparation and usual diet, the losses are around 20 %.
The vitamin D is consisted of group of several biologically active substances, of which the most important are vitamin D2, ergokalciferol, to be found in foods of plant origin, and vitamin D3, cholekalciferol, to be found in foods of animal origin.
In the human body, vitamin D acts as a hormone, it is formed at one point of the organism, but affects a different part of the body. The vitamin D ensures the intake and absorption of calcium and phosphorus and maintain their balance. It supports the immune system and may help in the psoriasis treatment.
The recommended daily intake of vitamin D is about 2,5 to 10 microgram. Pregnant and lactating women have a greater need for it, as well as infants and children. The lack of vitamin D disturbs the homeostasis of calcium and phosphate metabolism. The excess of vitamin D causes hypercalcaemia.
The most important foods source of vitamin D are liver, oil from fish liver, oil sea fish, fortified margarine and milk.
Vitamin D is sensitive to oxygen and light, its activity is not significantly affected by food storage or preparation.
Vitamin E is a major antioxidant. It is important to maintain the healthy cell wall and skin, muscles, nerves, erythrocytes, heart, and it is also responsible for the proper function of blood circulation.
The recommended daily intake of vitamin E is 8 to 20 mg. Its need is increased during exposure to sunlight and harmful influences, during increased physical exertion and when receiving large amounts of unsaturated fatty acids. The lack of vitamin E almost does not occur in healthy people, since it is present in nearly all basic kind of foods. The hypervitaminosis of vitamin E occurs only rarely, because there is no risk of overdose when receiving a normal diet.
The most important foods source of vitamin E are vegetal oils (such as sunflower and rapeseed), nuts, corn, pea, corn products, dark green leaf vegetables, eggs, liver and viscera.
Vitamin E is considered the most stable lipophilic vitamin. There is only a minimal loss of tocopherol during food processing, these losses are approximately 10 %.
The vitamin K supports blood clotting in the human body and, along with the vitamin D, is involved in the constant bone development and remodeling.
Both foods of plant and animal origin are sources of vitamin K, such as meat, liver, milk, vegetables and fruit. The recommended daily intake of vitamin K is around 0,01 to 0,14 mg. The infants and children up to three years have lower need of vitamin K intake. The most common cause of vitamin K hypovitaminosis is disruption of intestinal microflora caused by various drugs, e.g. antibiotics. Too high doses of vitamin K can accumulate in the body and lead to the breakdown of erythrocytes, damage the liver and cause jaundice in children.
There is not much information known about the stability of vitamin K yet. It has been found that vitamin K decomposes rapidly in the light, however its losses during food processing are minimal.
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Design of original piece of furniture for modern interior
Schořovská, Veronika ; Bomba, Jan (advisor) ; Podlena, Milan (referee)
This bachelor thesis is focused on issues of multifunctional furniture design which would be suitable for all apartments featuring a small surface area. The first chapter contains a partial overview of the historical progress in multifunctional furniture design, description of a variety of projects designed by worldwide known designers and a summary of trends in housing. The second chapter gives a detail description of the procedure of the furniture design. The third chapter is focused on my own multifunctional furniture design including a selection of suitable materials and its price calculation. In the attachments of this thesis there are sketches of the furniture in many different stages as the formation, constructional design and visualization.
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Analysis of selected localities suitability for freshwater pearl mussel young stages in upper stretch of Vltava River
Myslivečková, Lenka ; Bílý, Michal (advisor) ; Alena, Alena (referee)
In the river basins of Teplá Vltava and Blanice in Šumava, samples of floating and deposited detritus were taken for the purpose of their physical and chemical analysis with the goal to identify suitable stations for the growth and development of juvenile specimen of freshwater pearl mussels. 6 locations in total were examined (5 in the river basin of Teplá Vltava, 1 in the river basin of Blanice) where bio-indicator tests were also conducted. In all these locations, samples were taken 3 times during the month of July and, in 1 location, once a month in the period from June to November. In the samples, the amount of Ca, P, K, Mg, Na, the proportion of organic component and the ratio C/N were determined. This analysis showed that short-term oscillations of the composition of detritus correlate, regarding their span, with seasonal changes. The dependence of such seasonal changes of detritus on the extent of the river flow rate was not proved. Differences in the amount of organic component, K, Mg, and the ratio C/N between floating and deposited detritus were found. In terms of qualitative composition, both types of detritus varied in the amounts of plant and inorganic particles. In comparison with available results from springs in the area of Blanice, the detritus from rivers differed significantly from the detritus originating in springs in the presence of faecal pellets, amorphous matter and plant particles.
The growth of freshwater pearl mussels was dependent on the water temperature in the river, a dependence on the tested parameters of detritus was not proved, varying trends, however, were discovered (e.g. higher content of P, better growth). Water temperature showed to be dependent on the horizontal profile: water temperature rises with the direction of the water flow and the content of organic component in the detritus decreases with the direction of the water flow. Other trends in the horizontal profile were discovered as well but they were not proved statistically. Based on biological indicators, the locality of Ovesná (the lowest point down the river Teplá Vltava) was assessed to be the most suitable station.
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Development of British beef breeds of cattle
Khajlová, Anna ; Stádník, Luděk (advisor) ; Ducháček, Jaromír (referee)
This bachelor thesis is focused on suckler cows breeding. Literary review and further details are focused on the development and application of four selected beef breeds of British origin in terms of cattle breeding in the Czech Republic.
In the introduction I would like to describe mainly the origin and domestication of cattle. Much of the work is also devoted to meat production, its control and eventually classification and monetising the final product according to a single system SEUROP applicable in countries European Union. In this chapter were simultaneously described factors of the most important facts affecting meat performance that affects the overall results of the breed, including its profitability.
The second half of the thesis summarizes the basics of cattle breeding, organization during the calendar year and grazing. There is an idea of reproduction, calving and basic measures during rearing and weaning calves. In other chapters, are explained the circumstances of the development of animal husbandry and the current status of beef breeds in the country. Also described are two basic systems of breeding beef cattle, it is a system of intensive fattening and breeding no milked cattle under extensive conditions, which are characterized in detail in a separate chapter.
In the last chapters are presented in detail four selected meat breeds originating from the British Isles, which are in our conditions most frequently raised and used for extensive breeding system no milked cattle. There is also magnified view of history. It contains breeding these selected breeds, including the identification numbers of the development from the beginning to the present.
Besides to the detailed characteristics of these selected meat breeds and their descriptions are shown and summarized like the results of performance within the CHECKS performance of beef cattle. For each breed they are processed mainly results concerning the weight of calves in individual sections and their rearing till 365 days of age, in addition, depending on gender.
At the end, there are mentioned criteria of selection program, breeding goals and standard of these four selected meat breeds of British origin.
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Cheese defects and possible causes of their origin
Mazal, Marek ; Legarová, Veronika (advisor) ; Vladimír, Vladimír (referee)
This bachelor thesis is dealed with cheese defects and possible causes of their origin, which are participated in their formation. The problems of cheese defects is not focused only on technical apects, but it is also focused on microbial risks of possible contamination, the work is directed there at microbial quality of milk, which is crucial at the cheese manufacture. Microbial quality of milk is very important for cheesemaking, but the milk can be contaminated during the manufacture and also during the transport or storage. It is obvious for the reason of milk contamination, that milk has to be heat-treat, in order not to be damaged the final product. However heat-treat is not complete solution, because some microorganisms tolerate higher temperatures or they survive by formation of spores. Another way of contamination is entering of microorganisms during the cheesemaking, maturing and due to unsuitable storage. The cheese is not damaged only by microorganisms, but there are also significant physical factors, which can influence the quality of cheese, these are water activity, pH, salt content and temperature. These factors influence the natural microflora, which is present in the final product. However it is important realize, that there are differencies of susceptibility to forming pathogens among the cheeses, long aged cheeses are low risk due to it´s low pH, which prevents forming of pathogens so the pathogens can not endanger the cheese quality.
It should be considered suitable methods for elimination of pontecial risks and relevant defects during the cheesemaking. The most important methods should be regular hygien procedures, appropriate manufacturing and agricultural processes. The system of risk analysis and Hazard Analysis and Critical Control Points (HACCP) should be certainly present. For the prevention of cheese defect it is necessary regular control of specific paramaters at important stages of manufacture.
Very important matter is cosumption of cheese contaminated by mycotoxins, because consumption of mycotoxins is relatively high risk for human health. Mycotoxins are able penetrate into the cheese primarly due to presence of microscopic fungus, furthermore they can occur also as derivatives of mycotoxins, which are eaten by animals with their feed.
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The effect of water stress on the content of monosaccharides in potato tubers
Podhorecká, Klára ; Orsák, Matyáš (advisor) ; Hnilička, František (referee)
Bachelor thesis is focused on monitoring of influence on selected metabolites, especially monosaccharides. The first part is devoted to short characterization of potatoes, therefore the importance of this crop, morphology, cultivation and also are described demands of potatoes on environment and nutrition.
In the next section is detailed discussed problems of the chemical composition of tubers with a focusing on carbohydrates. Potatoes are globally consumed and are popular source of carbohydrates. Potatoes are rich in vitamins also, especially in vitamin C, B3 and B6. Potatoes contain a high content of minerals, especially potassium and magnesium, too. As another substances are in potatoes colorants, antioxidants, phenolic and related substances, proteins, and small amount of lipids. It is noted that proteins of the potato tuber are ranked among nutritionally valuable proteins of vegetable origin. Among this proteins is ranked Patatin, which is considered to be a major reserve protein and it is placed in the vacuoles. Substances, which has a negative effect on the human body are called Glycoalkaloids the opposite. Glykoalkaloids are synthesized by plants of the family Solanaceae. The most significant substances in potatoes are alfa-solanine and alfa-chaconine. Value of tubers is primarily determined by their chemical composition, which forms food and raw materials. The contents of sugars in the tubers are relatively low (0,5 % of the original mass), and even though their contents are important both in aspect of manufacturing and in sensory aspect. The main reducing monosaccharides are ranked glucose and fructose, typically with a concentration of 0,15 - 1,5 %. The sugar content significantly affects internal and external quality characteristics especially fried products. Several studies confirm that the accumulation of carbohydrates might help resist extreme stress conditions, especially low temperatures, salinity and water deficiency.
In the next chapter is created summary of stress conditions effects on plants with focusing on potatoes. In plants we can talk about stress, if variability of negative environmental factors exceeds a certain limit. The main theme and also the most limiting factor is deficiency of water in other words water stress. Also were mentioned other factors abiotic and biotic factors marginally.
By effects of stress reaction is created a specific level of adaptive skills. Temporarily it can lead to acclimatization, which increasing the resistance to abiotic stressors. Most of plants are trying to establish the tolerance to stress. In this Chapter were also described changes during storage and during heat treatments of potato, which leads to an undesirable darkening of the tubers. Excessive levels of reducing sugars cause unacceptable browning of fried products.
In the last chapter is described selected methods of determining carbohydrates. These methods are based on reducing properties of sugars, on their condensing reactions by color, measurement of optical activity, measurement of refractive index, separation methods and others.
The methodic of work clarifies the determination of reducing monosaccharides (glucose, fructose), sucrose by the high performance liquid chromatography (HPLC) in four selected varieties of potatoes from harvest of 2015.
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Comparison of nutritional values of different edible insect species
Maňhal, Daniel ; Kouřimská, Lenka (advisor) ; Kulma, Martin (referee)
The worlds limited agricultural resources will soon no longer be able to continue to support its ever growing population. One way to alleviate this problem is to integrate insects into the human diet, which is an increasingly common practice in Asia, Africa and South America. This practice has proven to be beneficial in a number of ways. Insects have better feed-conversion efficiency, transforming organic matter into larger amount of edible body mass than traditional livestock. Comparing to the livestock, insects have much smaller ecological impact on the environment. On the other hand, allergic reactions to toxins produced by some insects represent a potential risk of entomophagy. Nutritional values of insects depend on many factors, such as type of insect, its developmental stage, sex, and consumed feed. Generally, insects are a rich source of nutrients comparable to or even higher than traditional sources of meat.
Nutritional values of farm raised field crickets (Gryllus assimilis), originating from the Czech Republic, were analyzed in the experimental section of this thesis. Specifically, contents of dry matter, crude protein, fat and fatty acid profile were the main focus. The dry matter content was determined using an infrared technique. The crude protein content was measured using the Kjeldahl method. The Soxhlet method was applied for fat extraction. Extracted fat was determined gravimetric. Using gas chromatography, a lipid profile was obtained. Measured values were compared to those found in the literature. Emphasis was put on the comparison with other types of potentially edible insects and on the nutritional values of wild and farmed insects. Finally, these nutritional values were compared to the corresponding nutritional values of conventional meat to illustrate the benefits of entomophagy.
The analyzes showed that insect originating from the Czech Republic had very similar qualitative composition to species from different geographical regions and its nutritional value is fully competitive with conventional meat.
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Soil organic material, its components and reasons, why it is essential to differentiate them.
KRÁTKÁ, Petra
We are learning about a soil organic material as a unit from diverse media or lay and specialist literature. This informations are not differing the parts and characteristic of the soil complex. There are also terminological discrepancies which lead to incorrect deduction about soil fertility, decrease of topsoil content and poor management. This is a reason, why I do a literary summary in my thesis about a soil organic material and an individial soil components. It is a essential to distinguish the soil components for their different quality and the different origin after transformation precess. My task was a term clarification in soil organic material segmentation. We can divide it in two major groups: primary soil organic material and stable topsoil. The primary soil organic material is decomposed in exothermic mineralization process and is a origin of a nutriants and an energy for the soil edafhon and plants. The topsoil is a stable organic material and its matters significantly affect fertility, nutrient content, structure, aerial, aquatic and thermic regime of the soil. Morover the topsoil matters has a highmolecular HK ability to the heavy metals absorbtion.
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Welfare of cattle
Tajzichová, Nikola ; Chaloupková, Helena (advisor) ; Ilona, Ilona (referee)
The thesis Welfare of cattle is focused on well-being of the dairy cattle, specifically from the professional expert perspective, representing these days one of the very actual quality of cattle breeding factor. The objective of the thesis was to summarise the newest expert findings in the area of dairy cattle welfare and to find out Czech Republic breeders opinion on the dairy cattle welfare assessment and on the suitability of criteria for such assessment.
Cattle breeding represents one of the main sectors of the animal production, which serves as the primary source of milk, cheese and meat products. The quality of these products is directly dependant on the well-being of the cattle, which is at the same time essentially important for its complex good health condition, both physical and mental. In my thesis,
I have focused on the animal welfare as such, and I analyse it in detail from different perspectives. The thesis also addresses the important evaluation project Welfare Quality, whose methodology could become a foundation for standardization of cattle well-being assessment and its certification by means of passporting products quality and origin. Further, the thesis elaborates on the alternatives of such products welfare passportisation, which could also provide for authentication of products quality and welfare of animals in the studs.
I have used questionnaires for the empirical research, by means of which the dairy cattle breeders were interviewed. The questionnaires were composed of questions pertaining to basic information on concrete breeder and the stud, health condition of the animals, opinion of the breeder on animal welfare and suitable criteria for dairy cattle welfare assessment, and also questions addressing management and production characteristics of the stud. The thesis confirms the necessity of improvement of the awareness and knowledgeability of the breeders about the animals welfare, but also the need of animals life conditions improvement, and consequently the benefits of the introduction of welfare standardization and evaluation by means of all interested parties participation, and possibly also introduction of some form of certification of the quality and origin of the product, with respect to welfare.
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Use of therapy with Garra rufa fish for human treatment
Nacvalač, Tomáš ; Vrabec, Vladimír (advisor) ; Svobodová, Veronika (referee)
Garra rufa inhabits the biotopes of the rivers, small streams, reservoirs and lakes and it does not belong to the popular ones. Its original occurrence is in Iran, Iraq, Syria and Turkey. The fish lives at the bottom of streams and rivers, where the adhesive body sticks to the tissue to the bottom and rocks. Due to its low sexual dimorphism, its reproduction in captivity is more complicated. For its more effective reproduction, it is appropriate to prepare the spawning tank and induce suitable conditions (similar to conditions in the natural environment), like for example the rainy season. Garra rufa has currently become very popular, thanks to its use in ichtyotherapy and also that it is performed in so-called "fish pedicure". In some countries, this therapy is prohibited due to insufficient hygiene and poor rearing conditions. I have chosen the topic of my Bachelor thesis to focus and collect scientific evidence of information to improve the opinion of this type of therapy. In the work I cite use of the appropriate technical equipment used in the tanks, which increase the safety and quality of procedures for the fish as well as for people who pass through the general or local therapy with the help of Garra rufa fish. I processed the study also from the point of view of the risk of treatment when scientific teams tested the water in the tanks for the presence of bacteria, such as Mycobacterium marinum, Aeromonas hydrophila, Escherichia coli or Staphylococcus aureus. And said possible modes of transmission of infection to the person undergoing the therapy. Not all uses of this fish are the only negative. Some may on the contrary be very useful. For example: Ichtyotherapy, the treatment of persons suffering from Psoriasis, Atopic Dermatitis, or Acne. The results of these therapies are very good and in compliance with the necessary health and safety recommendations are safe This fish is also beneficial in the field of aquarium hobby, especially for removing algae. According to one study, mentioned in my Bachelor thesis, Garra rufa positively affects the treatment of different species of fish incaset of an outbreak of infection in the tank. The work discusses about the current situation in the breeding and safety of the above-mentioned procedures in the Czech Republic. I processed this issue based on Ing. Jaroslav Macenauer experiences. He has provided me with the information about the origin of the imported fish, proper selection of tank equipment and about the level of care that is necessary to carry out during the procedures.
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