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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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Effect of breed and storage on goat milk quality
Hončíková, Barbora ; Potůčková, Miroslava (advisor) ; Michaela, Michaela (referee)
The aim of this diploma thesis was in theoretical part to summarise current knowledge about composition, physico-chemical, technological and sensory properties and cryostability of goat milk including a comparison of this characteristics for dairy goat breeds which are used for industrial and farm dairy production.
Goat milk has high nutritional and therapeutic value. It is suitable for dairy industry processing as well as cow milk. In the Czech Republic, where is traditional cow milk consumption, the interest of consumers in goat milk products increased recently. The main Czech dairy goat breeds are White and Brown-Shorthaired Goats.
In the practical part of diploma thesis were compared the 2 main Czech dairy goat breeds, White and Brown-Shorthaired Goats, with a rare breed Girgentana Goat. Cryostability of goat milk was observed for 16 weeks (0, 1, 2, 3, 4, 8, 12 and 16 weeks) for White and Brown-Shorthaired breed. Characterized parameters were main components (total solid, non-fat solid, fat, lactose, crude proteins and casein), minor components (citric acid, urea, free fatty acids and fatty acid profile), physico-chemical properties (density, freezing point and titratable acidity), technological properties (cheeseability, fermentability and thermostability) and for fresh milk also sensory identity and acceptability.
It was found that milk from Girgentana Goats contains the significantly (p < 0.05) highest amount of total solid, fat and lactose. The highest amount of crude proteins (p < 0.05) was on the contrary observed in Brown-Shorthaired Goat milk H1. These two samples had also the best cheeseability (p < 0.05) but the worst sensory acceptability because of their strong goat flavour and taste. During the storage test of White and Brown-Shorthaired Goat milk samples was found significantly (p < 0.05) negative influence of storage in frozen state only on cheeseability. This could be explain by the negative changes in the conformatin of proteins, especially casein fraction.
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Characterization of bifidobacteria and lactobacilli isolated from intestinal tract of wild pigs
Šimurka, Julius ; Rada, Vojtěch (advisor) ; Švejstil, Roman (referee)
The microbiota of the gastrointestinal tract is considered as "acuqrated organ" located in a host organism. There are many performs of specific functions. The microbiota composition changes during the life of the individual, depending on his environment and nutrition. The process of identification and characterization of the bacteria from the intestinal microbiota is an important prerequisite for understanding the function of this "acuqrated organ".
This work deals with the anatomy and physiology of the digestive tract (DT) of pigs and evolutionary and eating differences of wild and domesticated pig, for understanding the natural environment of bacteria from DT, which in turn affects the bacterial diversity of the intestinal microbiota. Also mentioned is the process of domestication, which influenced the present form of domestic pig. The work includes the characteristics of lactobacilli and bifidobacteria, which contains the descriptions, taxonomy, metabolism and habitats. The work also shows the insulating media used in practice for the isolation of bifidobacteria and lactobacilli from DT of pigs and methods of their identification and related methods of characterization.
The available literature confirms the differences in the composition of microbiota DT between wild and domesticated pig, that correlate with other studies which study microbiota diversity of other domesticated and wild animals. The diversity studies of humans microbiota, also confirms the broad spectrum of bacterial species in primitive tribes of humans compared with urbanized man.
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Localization and characterization of binding sites for CA2+ binding proteins and phosphatidylinositol phosphates on intracellular termini of TRP channels
Boušová, Kristýna
This dissertation concerns with characterization of binding sites for calcium binding protein S100A1 and phosphatidylinositol phosphates on intracellular regions of transient receptor potential channels (TRPs), particular from canonical (TRPC), vaniloid (TRPV) and melastatin (TRPM) families. TRPs represent superfamily of important mediators that play critical roles in sensory physiology: contributions to taste, olfaction, vision, hearing, touch and thermo- and osmo- sensation. They serve as non-selective and nociceptive membrane receptors responsible for the modulation of driving force for cations entry into the cell. TRPs are composed from six transmembrane domains and N- and C- termini intracellular regions. Overall four monomer units form a characteristic assembly of functional channel. It was demonstrated that most of this almost thirty-member family transporters are activated by a variety of different stimuli and function as signal integrators. The most examined intracellular TRPs modulators are cytosolic calcium binding proteins and membrane anchored phosphatidylinositol phosphates (PIPs). These signal integrators bind specific domains in intracellular termini of TRPs, thereby change their structure and activate or inhibit the transportation function of receptor. To identify a novel ligand...
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Preparation and characterization of analogs of tetrapeptide B 23 -B 26 and octapeptide B 23 -B 30 of human insulin
Ježek, Jan ; Velek, Jiří ; Velková, Vlasta ; Klasová, L. ; Barthová, J. ; Ubik, Karel ; Kašička, Václav ; Barth, Tomislav ; Wollmer, A. ; Huml, Karel ; Hauzerová, Linda ; Brandenburg, D.
Gly-Phe-Phe-PheNH2, Gly-Phe-Phe-N(Me)Phe-NH2, Gly-Phe-N(Me)Phe-Phe-NH2, and Gly-Phe-Phe-N(Me)Tyr-NH2 and octapeptides Gly-Phe-Phe-N(Me)Phe-Thr-Pro-Lys(Pac)-Thr-OH and Gly-Phe-Phe-Phe-Thr-Pro-Lys(Pac)-Thr-OH. The compounds were isolated by preparative HPLC and characterized by amino acid analysis.
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Molecular genetic characterization of vancomycin-resistant enterococci
Bubeníček, Karel ; Rada, Vojtěch (advisor) ; Igor, Igor (referee)
Summary
Objectives and hypothesis: This thesis concerns the study of plasmids of vancomycin-
resistant enterococci isolated from feces of American crows in the years 2012 - 2013 period.
The hypothesis is that, in various environments, there is one or more types of
epidemiologically significant vanA gene-carrying plasmids that are capable of horizontally
spread.
Methods: Based on PFGE method the number and size of plasmids were detected in selected
isolates of vancomycin-resistant E. faecium. Using PCR method the isolates were subjected
to detection of genes of replicases, relaxases and toxin-antitoxin system of plasmid-bound
resistance genes. Using 19 primers were characterized types of Tn1546.
Results: Of the 12 tested vancomycin-resistant isolates of E. faecium the following number
and size of plasmids was proven using PFGE method: 2 isolates contained two plasmids
(17%), 3 isolates contained three plasmids (25 %), 5 isolates contained four plasmids (42 %)
and 2 isolates contained five plasmids (17 %).
All isolates (n = 12) were then subjected to the detection of genes of replicases, relaxases and
toxin-antitoxin system for typing of plasmids from each plasmid families.
RepA_N family of plasmids:
genes characterizing plasmids related to pRUM: rep17 in 11 isolates (92 %),
gene Axe-Txe was detected in 5 isolates (42 %)
genes characterizing plasmids related to pLG1: rep20 in 7 isolates (58 %)
genes characterizing plasmids related to pAD1: relpAD1 gene was detected in one isolate (8 %)
Inc18 family of plasmids:
genes characterizing plasmids related to pIL501: rep1 gene detected in one case (8 %)
genes characterizing plasmids related to pRES25: rep2 gene in 2 isolates (17 %)
genes characterizing plasmids related to pEF1: relpEF1 detected in 11 isolates (92 %)
pHTB family of plasmids:
genes characterizing plasmids related to pHTB: rep22 gene was detected in 4 isolates (33%) and in 2 isolates gene relpHTB was detected (17%)
RCR family of plasmids:
genes characterizing plasmids related to pRI: positive detection of Rep14 gene in 8 isolates (67%) and in 4 isolates relpRI gene was detected
Small theta-replicating plasmids:
genes characterizing plasmids related to pEF418 plasmids: rep18a gene in 2 isolates (17%)
genes characterizing plasmids related to pB82: rep18b gene was detected in one isolate (8%)
genes characterizing plasmids related to pCIZ2: relpCIZ2 gene was detected in 9 isolates tested (75%)
Types of transposon Tn1546
Using the PCR method types of Tn1546 were characterized. In 4 isolates (n = 12; 33 %)
Tn1546 was characterized as a F3 type. In one isolate (8 %) Tn1546 was characterized as a
type F5, in one isolate (8 %) as a type PP-16. In 6 isolates Tn1546 was untypeable. Most
likely these are new, yet unknown types.
Conclusion: This is the first study of plasmids of vancomycin-resistant isolates E. faecium
isolated from feces of American crows. These results emphasize not only a high proportion of
plasmids in individual isolates, but also a high proportion of genes with horizontal transfer.
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Morphological and genetic diversity of camu-camu (Myrciaria dubia, Mc Vaugh) in Peruvian Amazon
Šmíd, Jan ; Lojka, Bohdan (advisor) ; Petra, Petra (referee)
Camu-camu (Myrciaria dubia, McVaugh) is currently one of the most important fruit species that is grown in the Peruvian Amazon, as well as in Brazil, Colombia or Bolivia. Larger plantations were established only in the last two decades and a substantial part of the production is still obtained by collecting fruits from the wild. Domestication of the species is still at its very beginning; most of the farmers cultivate the plants without any breeding or just after simple selection. The aim of this study was to characterize the morphological and genetic variability of cultivated and natural populations of camu-camu in the Peruvian Amazon and also to compare the variability among and within these populations. In total we have sampled 13 populations; 10 wild populations in Iquitos region, three cultivated populations in Pucallpa in Peruvian Amazon. For genetic analysis, the leaf tissue samples were collected from ten individuals from each population (n=126), and for morphological data were collected from five trees of each population (n=65). To assess the genetic diversity, we used seven microsatellite primers that were developed from available DNA sequences. Using various genetic softwares, major indexes of variability were detected and dendrograms of relatedness of populations and individuals were created. The statistical analysis did not reveal statistically significant differences for most of the morphological descriptors, except for the fruit parameters. Surprisingly, the trees from wild populations had higher fruit and pulp weight and their fruits contained less seeds compared to cultivated populations. The observed heterozygosity was 0.347 and 0.404; expected 0.516 and 0.506; inbreeding coefficient was 0.328 and 0.200 for wild and cultivated populations, respectively. Wild populations could be divided according to the dendrogram into two completely different groups. In cultivated populations, their approximate origin was determined. All the results indicated a high genetic variability but also a high degree of inbreeding. This can be explained by isolation of the populations from each other or low number of individuals in the population. This high level of diversity can be explored for selection of superior individuals and further possibilities of breeding.
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Analysis and characterization of BRCA1 splicing variants.
Hojný, Jan ; Kleibl, Zdeněk (advisor) ; Souček, Pavel (referee)
The Breast cancer gene 1 (BRCA1) codes for nuclear phosphoprotein with a key function in the regulation of DNA damage response. The BRCA1 protein contributes to the formation and regulation of protein supercomplexes that participates on the DNA double-strand break repair. These protein supercomplexes are formed by the protein-protein interactions between highly conservative protein motives in BRCA1 and its binding partners. Except to the wild type form of BRCA1 mRNA containing entire set of 22 exons coding for the 220 kD protein, numerous alternative splicing variants (ASVs) BRCA1 mRNA has been described. These ASVs code for BRCA1 isoforms lacking several critical functional domains. It has been proposed, that formation of BRCA1's ASVs represent a tool for regulation of BRCA1 function. Only poorly has been characterized a complex catalogue of in various human tissues and their expression. This study aims to address these questions. We optimized the identification of BRCA1's ASVs including those covering the entire transcripts of the wt BRCA1 mRNA with length exceeding 5.5 kb. In further analysis, we characterized 13 BRCA1's ASVs in RNA samples isolated from peripheral blood mononuclear cells (PBMNC) obtained from patients with breast cancer (BC) and control subjects. The majority of the identified...
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