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Antioxidant, anti-proliferative and immunomodulatory effect of fruits, vegetables and mushrooms in vitro
Doskočil, Ivo ; Havlík, Jaroslav (advisor) ; Orsák, Matyáš (referee)
Recently there has been an increasing interest in discovering of new species of plants and mushrooms which have antioxidant or anti proliferative activity. The interest is caused by the fact that these species have medicinal and food utilization. These properties of plants and mushrooms can be used when dealing with many diseases which may be connected with oxidative stress (inflammatory bowel disease, cardiovascular disease, hypertension, and tumour disease, etc.). The thesis propounds characteristics of in vitro antioxidant and anti proliferative activity of 19 types of juices and 28 methanol extracts of fruits and vegetables, which are common parts of a diet. In the thesis there are also characteristics of 13 ethanol extracts of edible mushrooms of the order of Polypore (Popyporales). Antioxidant activity was quantifie by 2, 2 diphenyl 1 picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC), and inhibition of nitric oxide (NO) production. Cytotoxicity was measured by MTT (3 (4,5 dimethylthiazol 2 yl) 2,5 diphenyltetrazolium bromide. Immunomodulatory activity was determined by an assay of phagocytic activity of human neutrophil granulocytes. Further a total phenolic content (TPC) and total beta glucan content were investigated; these are considered to be the potentially active constituents participating in mentioned activities. From the obtained results it is evident that juices (TPC = 1603.2 mg GAE/L; ORAC = 438.5 umol TE/g) and a bilberry (Vaccinium myrtillus) fruit extract (ORAC 836.6 umol TE/g; DPPH = 404.6 umol TE/g) showed the highest antioxidant activity of all tested samples of fruits and vegetables. Capsicum (Capsicum L.) juices (TPC = 642.1 mg GAE/L; ORAC = 127.9 umol TE/g) and a radish (Raphanus sativus L.) extract (ORAC 724.5 umol TE/g; DPPH = 52.2 umol TE/g) also proved to have the high values of antioxidant activity. From the tested fruits and vegetables the following inhibited to produce a nitric oxide: onion (Allium cepa L) juices (lowered the NO production by 57%), tangerine juices (Citrus reticulata Blanco)(by 52%), broccoli (Brassica oleracea var. botrytis italic) extract (by 21%), and orange (Citrus sinensis Pers.) extract (by 10%). Concerning edible mushrooms, Lentinus tigrinus (Bull.) Fr. (TPC = 216.2 umol GAE/g of extract), Ganoderma lucidum (Curtis) P. Kras (TPC = 257.9 umol GAE/g of extract), and Royoporus badius (Pers.) A.B. De (TPC = 257.8 umol GAE/g of extract) presented the highest phenolic content. Sparassis crispa (Wulfen) Fr. (117.4 mg/g of extract) had the highest content of beta glucan. Substantial effect on phagocytic activity of granulocytes was noticed in connection with Neolentinus lepideus (Fr.) Redhead & Ginns, Polyporus squamosus (Huds.) Fr., and S. crispa. In connection with the latter of mentioned mushrooms, a moderate inhibitory effect towards HT 29 human colorectal adenocarcinoma cell line (IC50 = 107 ug/ml of extract) was noticed. The results indicate that the tested plants and mushrooms can be beneficial when reducing the negative effects of oxidative stress. The oxidative stress has been recognized as a contributing factor to a whole range of diseases and the reduction of the oxidative stress may lead to the decrease in the possibility of the diseases´ progression. The results show the possible favourable effects on the human health. When evaluating the results, the following fact should be taken into consideration; the in vitro tests and screenings are considered to be the first phase of systematic research of the effects and serve for the choice of respondents for further detailed studies.
Importance of vitamins in human nutrition
Želinská, Kateřina ; Orsák, Matyáš (advisor)
This Bc. thesis discusses the basic characteristics of vitamins and their essential role in the functioning of human organism. The first half of the work analyses and addresses the vitamins classification and their structure from the chemical point of view. The second half describes in detail the importance of vitamins for the human body, and for the synthetic substitution of these substances.
Effect of short-term water deficit and rehydration on pigments content in the leaves of selected species of leafy vegetables
Scholzová, Kristýna ; Hnilička, František (advisor) ; Orsák, Matyáš (referee)
In this bachelor's work was investigated the influence of short-term water deficit and rehydration on the content of pigments in the leaves of selected varieties of leafy vegetables. The objective of the greenhouse experiment was determination of the content of pigments in leaves depending on the plant species and the evaluation of the effects of water deficit and subsequent rehydration on the content of pigments in the leaves of selected species of leafy vegetables: lettuce, rocket and chard.
Changes to the contents of proline and relative electrolyte leakage of the selected genotypes of poppies depending on the influence by low temperature
Kudrna, Jiří ; Hnilička, František (advisor) ; Orsák, Matyáš (referee)
The object of this thesis is to study the effect of low temperatures, proline content and relative elektrolyte leakage in a selected range of varieties of opium poppy. Experiment included 18 poppy varieties with different contents of morphine. Poppy seeds for this experiment were provided by GB Oseva Pro s r.o., o.z.VÚO Opava a Český mák s.r.o. Poppy seeds were sown in containers of a size of 7,5x7,5 cm. Used cultivation medium is mixture of garden substrate A with quartz sand in a ratio of 2: 1. Plants were grown under controlled conditions in grow chamber Conviron E8. Before starting the experiment, the temperature was at 10 ° C during day and 5 ° C over night. Light cycle was 13 hours light and 11 hours darkness. The maximum value of irradiance was 800 micromol. The experiment was initiated in phase of rosette develoment. At this developmental stage were the plants exposed to frost temperatures (-5 ° C) over night and chill temperatures (10 ° C) duringthe day. After a week the plants were regenerated for 1 week at 5 ° C over night and 10 C during the day. All tested plants were in two day intervals measured of proline concentration after exposure to low temperature stress. At the same intervals as proline, were measured the values of relative elektrolyte leakage (Rel%).The obtained results show that the influence of low temperature causes increase of proline level. Control winter-crop variety Zeno exhibited the high kontent of proline (693.33 microg.g -1) in comparison with the spring poppy varieties. After regeneration were afected varieties Lazur, Opal, Buddha, Korneuburger Weisser, Aplaus, Major, Sokol, Zeno reduced the content of proline under the influence of higher temperatures. On the other hand the varieties Ofeus, Tatranský, Opex, Orbis, Maraton, Florián, Marianne and Albin were reversed with an increase of proline level. Proline concentration levels were constant and unchanged in case of varietes Postomi and Akvarel. Values of relative elektrolyte leakage were increased proportionately with length of exposure to low temperatures on the tested plants. The lowest value of membrane damage was after exposure to low temperatures observed in case of variety Zeno (23.53%). In the case of spring varieties was lowest membráně damage estimated in a variety Korneuburger Weisser (44.88%), while the highest was in the variety Orfeus (53.15%). It demonstrated the different responses of individual poppy varieties at low temperature. Most sensitive to low temperature were varieties Orfeus, Postomi, Akvarel, Orbis, Sokol and Marianne. As less sensitive to stress caused by low temperature seems to be spring varieties Opex, Buddha, Korneuburger Weisser, Albín.
Changes in gas exchange of selected genotypes of poppies depending on the influence by low temperature
Málek, Jan ; Hnilička, František (advisor) ; Orsák, Matyáš (referee)
The Czech republic is one of the biggest Opium poppy producers. In 2015, this plant was grown in an area of approx. 32 650 ha. Since the poppy is usually sown quite soon in the spring, it can be damaged (or negatively affected) by low temperatures. The main objective of this Bachelor thesis was to determine the speed of gas exchange in several poppy species affected by low temperatures. In this research, altogether 12 various genotypes of Opium poppy (Papaver somniferum L.) were included in (development phase 35 BBCH). These were concretely following poppy species: CM 112, Sokol, Major, Opál, Florián, Albín, Postomi, Marianne, Budha, Lazur, Aplaus and Orbis. Under controlled conditions of a clima-box (Conviron), the plants were exposed (within 1 week) to daily temperatures of 10 °C and night temperatures of -5 °C. After one week, the night temperature was increased to 5 °C, while the daily temperature remained the same (i.e. 10 °C). In following two weeks, there was measured the photosynthesis- and transpiration- speed (using the infrared gas analysator LDpro+SD). Base on measurements made, there was stated, that there could be noted quite big differences in photosynthesis- and transpiration- speed in particular poppy genotypes involved. This fact proves the existency of obvious differences in gas exchange speed of particular poppy species included in this research. Between the particular measurement terms, there could be also noted differences in photosynthesis- and transpiration speed, which proves the influence of low temperatures on photosynthesis- and transpiration speed.
Phenolic complex of medicinal plants
Vaníčková, Klára ; Orsák, Matyáš (advisor) ; Hniličková, Helena (referee)
This thesis deals with medicinal plants, that contain phenolic complex. Emphasis on interdisciplinary relations with the chemistry and the use of theory in practical life. At the beginning, I also focused on the concept of health and lifestyle, which is an inherent part of that topic. Content is also the use of medicinal plants, basic plant description and important characteristic of the phenolics contained in plants. At the theoretical part is processed an overview of selected kinds of medicinal plants to draw attention to the content of the substance, especially with the phenolic complex special effects and their possible use.
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.
Biogenic amins in beer
Zima, Matěj ; Orsák, Matyáš (advisor) ; Braný, Pavel (referee)
One of the most popular and widely used alcoholic beverages is beer. There is a long-standing tradition of beer production in the Czech Republic and it is our significant export commodity. Hops, specifically the so called Saaz Late, is a typical ingredient in the production of bottom fermented a Pilsen kind of beer that has made us famous in the world. Beer is a complicated beverage and its production is not an easy process, although it may seem differently at first glance. Apart from the convenient ingredients, for the production of beer are also needed technological facilities and most importantly the knowledge. The procedure itself consists of grinding malt, mixing it with water and mashing process, which includes a shortage of polysaccharide chains by influence of malt enzymes. The extracted product is called hopped wort and it is further boiled together with hops. This process is in Czech language known as chmelovar (hereinafter referred to as wort). During the wort, there are some bitter substances coming to work (this is how mixture of ingredients and water is generally called during the whole process of production), the bitter substances are specifically alfa bitter acids and beta bitter acids. The extracted product is called hopped wort. After fermenting the hopped wort, there comes a stage of main and secondary fermentation. During this phase two crucial ingredients of beer are produced. Alcohol and carbon dioxide. Traditional for Czech regions is the bottom fermentation in which yeasts are descending to the base of a container. Biogenic amines are one of many components of the beer. However, they can be found not only in the beer, but also in almost all basic foods. We can find them in meat, fish, vegetables and fruits, and even in different concentrations. Their production is often associated with the fermentation process. Regarding the content of biogenic amines in beer, due to the research it is obvious that a part of them gets into the beer from the original raw materials. Another part arises during the fermentation process. Tyramine and histamine (among others), discovered in the beer, can have a serious impact on human health. During the consumption of large quantities of such a beer, but even other foods that contain a lot of these biogenic amines, it may affect the circulatory system, breathing, cause a facial flushing and in extreme cases even cerebral haemorrhage. The intoxication by histamine is often manifested as food poisoning or allergic reactions.
Low- and nonenergy sweeteners
Trnková, Lenka ; Orsák, Matyáš (advisor) ; Hniličková, Helena (referee)
Low- and no-calorie sugar subtistutes are compounds that provide food with its sweet taste. As the term suggests, they have lower or no food energy and usually are characterized by higher sweetness than sucrose. For that reason, these substances are especially used during the treatment of diabetes mellitus, to reduce the energy content of food or in prevention of dental caries. Natural sweeteners were discovered a long time ago, during the search for sustenance. For example Stevia was used by South American Natives even before the European conquest of the territory. However, the history of artificial sweeteners is not too significant, because it relates to breaking the laboratory rules. That is how saccharin was invented in 1878. Sugar substitutes are added to food on purpose, adjusting the taste or extending the shelf life of foods. In the EU, every approved sweetener has got an E-code, which is displayed on the label. Sugar substitutes can be grouped according to their origin, their nutrition value or their chemical structure. This thesis discusses low- and no-calorie sugar substitutes that can be synthetic or natural. Mentioned synthetic sweeteners typically contain less then 21 kJ per portion. These intensive food additives possess many times the sweetness of sucrose. The main representatives of this group are saccharin, cyclamate, acesulfame K, sucralose and aspartame with its derivatives. The group of natural sugar substitutes constits of substances like erythritol, D-tagatose, trehalose, neohesperidin dihydrochalcone, stevioside and thaumatin. There are some limitations confirmed by expert studies. For example, patients suffering from diabetes mellitus should mainly use synthetic sweeteners, because of their low nutritional value. Even though in some states certain sweeteners are forbidden, safety studies say that there are no adverse effects, if the recommended daily intake is respected. Sugar substitutes, therefore, can be considered safe.
Influence of different lengths and vinification yeast strains on the subsequent conduct of malolactic fermentation
Hornáková, Ľubomíra ; Orsák, Matyáš (advisor) ; Hnilička, František (referee)
The topic of this bachelor thesis is to determine individual organic acids, specifically tartaric, malic and lactic acids in grape must after a final fermentation using high performance liquid chromatography. The reason behind examining the levels of organic acids are various microbiological conditions of fermenting musts with the subsequent influence on the sensoric quality of the resulting wines. In the theoretical section we describe the technological processing of grapes during wine making, characterize the anatomical and chemical structure of the used grapevine, grape microbiota and its influence on the process of organic acid transformations. Separate chapters are dedicated to specific species of the yeasts Saccharomyces cerevisiae, Torulaspora delbrueckii and bacteria Oenococcus oeni for their fundamental place in the fermentation process. The influence of this microbiota is evaluated in the practical section, where the records of individual inoculations are noted and the fermented musts are analyzed using the separational method of high performance liquid chromatography. The levels of organic acids and the length of fermentation gives evidence of the influence of the participating microbiota on the length of wineification and the physico-chemical parameters of fermentation. For the general assesment of efficiency of the used microbiota on individual fermentatated musts, a sensoric evaluation of samples is conducted.

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