Isolation of plant DNA is complicated due to the presence of polyphenols, polysaccharides and other metabolites, that are isolated together with DNA. These compounds can affect the yield and quality of DNA and can inhibit a polymerase chain reaction (PCR). A modern, simple, and fast method of DNA isolation in molecular biology laboratories is magnetic separation based on reversible DNA immobilization on magnetic particles. These methods allow to obtain DNA of high quality and purity. In the experimental part, magnetic microparticles PGMA 2 mg/ml and magnetic nanoparticles functionalized by polylysine (PLL) 0,2 mg/ml were used for isolation of plant DNA from vegetables (carrots), fruits (pear, apple, lemon, mango) and heat treated food products for children (Hami first carrot, Nestlé fruit pocket, dmBIO pear carrot apple, Hello fruit snack with apples and Hello fruity snack with mango). The efficiency of separation of magnetic particles with bound DNA using a magnetic needle and a magnetic separator were compared. The quality and quantity of isolated DNA were verified by spectrophotometric analysis. The amplificability of isolated DNA was tested in a conventional PCR using primers specific for plant ribosomal DNA (rDNA). PCR products were analyzed by agarose gel electrophoresis. Major fluorescent bands were of 700, 350 and 220 bp corresponding to three different rDNA amplicons. DNA was isolated from heat treated food products for children in a PCR-ready quality. Only 220 bp long PCR products were detected, that indicated DNA degradation. The identity of PCR products was determined by restriction fragment lenght analysis (RFLP) using NlaIII enzyme cutting the rDNA subregion (ITS1) of Daucus carota (carrot). The digestion profiles were in a good agreement with those predicted from bioinformatic analysis confirming, thus, the specificity of the developed PCR method.

The thesis was focused on the preparation and optimization of the preparation of wound dressing from materials with bioactive ingredients. In this work were prepared nanofiber dressings based on polyhydroxybutyrate and non-fibrous dressings from alginate and chitosan. Nanofibers were prepared by electrospinning and forcespinning methods. The bioactive components, which were used to functionalize the prepared dressings, were plant extracts, clotrimazole, ampicillin, lysozyme, and proteolytic enzymes. The theoretical part is focused on the description of the use of nanofibrous and non-fibrous materials in medicine, characterization of materials for the production of wound dressings and bioactive components. Furthermore, this section describes the methods used to prepare and characterize wound dressings. In the practical part were prepared aqueous and oil extracts from selected plants. Extracts were characterized for polyphenols content and antioxidant activity. PHB-based nanofibers were prepared using electrospinning and forcepinning methods. Nanofibers were enriched with selected plant oil extracts and clotrimazol. Modified nanofibres were detemined for antioxidant activity, short-term and long-term stability. Non-fibrous wound dressings were prepared from alginate and chitosan. These dressings were functionalized by the addition of selected aqueous extracts, ampicillin, lysozyme, papain, bromelain, and collagenase. Non-fibrous wound dressings were determined for antioxidant activity, short-term stability and proteolytic activity. The prepared wound dressings were tested for their antimicrobial effects on cultures of Micrococcus luteus, Serratia marcescens, Staphylococcus epidermidis and Escherichia coli. In conclusion, successfully prepared bioactive wound dressings with antioxidant and antimicrobial agents were tested for safety on human cells. The determination was performed using the MTT cytotoxicity test on human keratinocytes.

Extraction of nucleic acids is an important step for all molecular biological studies. The process of isolation of plant DNA is complicated due to the presence of polyphenols, polysaccharides and other metabolites. They can be co-isolated with DNA and act as PCR inhibitors. The aim of this study was to compare CTAB extraction procedure, Qiagen DNA easy kit, direct homogenization, carboxyl-functionalised magnetic non-porous HEMA based microspheres and combination of the above mentioned methods for DNA isolation from different plants. The DNA was evaluated regarding concentration, purity and amplification in PCR. All methods provided DNA that could be used in downstream PCR applications. However, there were differences regarding yield, purity, labour intensiveness and cost. Combination of direct homogenization and magnetic microspheres coated by carboxyl groups was isolated DNA from various plants and plant foods in a quality suitable for convectional PCR, real time PCR and restriction analysis. This method is fast, simple and does not require work with harmful substances.

This thesis deals with alternative thermal degradation of electrical insulating liquids. The theoretical part describes the current state of the problem, electrical insulating liquids, their classification and types. There are described properties of electrical insulating liquids, their models of aging and diagnostic methods in accordance with the appropriate standards. In the practical part are chosen by representatives of alternative electrical insulating liquids and there are determined their dielectric characteristics in the initial state. According to the measured values is chosen five candidates for which it is designed and implemented an accelerated degradation test. During the test are measured dielectric parameters of the selected oils. Measured dependencies are mathematically approximated. In conclusion, the results are compared and physically interpreted in view of oxidation stability.

Intraspecific plant-soil feedback is a relationship in which plant affects the composition of the soil and such modified soil affects growth of the same plant species. This relationship and its intensity may be linked with plant dominance and invasiveness. Dominant species can alter the composition of the soil in their favor and thus show positive intraspecific plant-soil feedback. As the invasive species are commonly being dominant in their new environment, it can be expected that intraspecific positive plant-soil feedback could be an important factor allowing the invasive species to achieve their dominant position and become invasive. To test if the existence of positive intraspecific feedback could be a general mechanism underlying plant invasiveness I compared intraspecific plant-soil feedback in a group of invasive and introduced, but non-invasive, plants in the Czech Republic. I did this using a preselected set of 34 species - 17 invasive and 17 non-invasive. For realization of the project I used the method of two-phase experiment. The first phase is called soil conditioning - influencing of soil by the plant. In the second phase the same plant species are planted in conditioned soil from the first phase and in control (unconditioned) soil. Then I compared plant biomass from conditioned and...

This diploma thesis is focused on issues concerning the stability of selected vegetable oils which are used in cosmetic industry. The stability of eight oils without additives were determined by a differential scanning calorimeter. In the first phase, the temperatures of oil degradation were determined for different rates of heating, i.e. nonisothermal stabilities. They were consequetly used to calculate isothermal stabilities alias induction periods. The calculation of induction periods was completed by using integral isoconversional methods, which applied four different temperature functions. One of the temperature functions corresponded to Arrhenius equation while the others to non-Arrhenius functions. The confrontation of induction periods under standart conditions showed that an optimal temperature function to calculate oil stabilities is one of the non-Arrhenius functions in exponential form. We can state that all oils are degraded by similar, if not the same, mechanism. The specified stabilities, in periods of months, have proved the importance of using stabilizers and other additives in the commercial and technological use of vegetable oils.

Next generation sequencing is a modern method applied in plant virology for sensitive detection of previously characterized and novel pathogens without any preceding knowledge of them. In this study three novel and two already described viruses were detected by de novo assembly of Illumina single-end reads ( Hi-Seq 2500 system) from total poly(A) enriched RNA of diseased red clover (Trifolium pratense) and indicator plant (Nicotiana occidentalis 37B). The complete genomic sequence of novel Red clover carlavirus A (RCCA) was determined from Illumina reads, 5´, 3´ RACE, cloning, RT-PCR and Sanger sequencing. The presence of RCCV was also confirmed in mechanically inoculated tobacco plant.

Three of Impatiens species are widespread in the Czech republic, one is native, two of them invasive. Because all species occur in relatively similar habitats, the question is, whether the invasive species can negatively affect the native species, or even the original can can be displaced. The aim of the thesis was: (i) to compare habitat requirments of the Impatiens species, (ii) to determine if the coexistence of species is possible, (iii) to assess the impact of invasive species to the original species. The investigation was carried out using two sets of permanent plots in 5 localities. In the first set with a total of 84 plots (combinations of occurrence of the three species) site characteristics as tree cover, soil humidity, slope and bare land cover were directly measured and nutrient, light, humidity and soil reaction characteristic assessed using Ellenberg indicator values. The second set contained a total of 45 plots with one of the native-invasive congener pair being removed and the intact controls. Number, cover and height of the plants were assesed. The key enviromental factors determining distribution of the species were soil moisture for I. noli-tangere and I. parviflora, and tree cover for I. glandulifera and I. parviflora. Ellenberg indicator values had poor explanation value;...

Nutrients are usually patchily distributed in natural soils. Plants are often able to respond to nutrient heterogeneity in artificial conditions by active plastic changes of root system morphology. The occurrence or magnitude of a foraging response can be altered by the presence of competition. However, it is unclear to what extent root foraging takes place in the field. I conducted a field experiment in order to determine the effect of an artificial nutrient patch on fine belowground biomass of (a) an established community and (b) model plants. The study array consisted of a grid of 30×30 cm plots with model plants located in the centre. Half of the plots contained the artificial patch located 5.5 cm from the model plant. Fertilizer patch treatment did not increase mean plot fine underground biomass. Instead, fine underground biomass was higher in places of greater soil moisture estimated from mean plot EIVs. Neither total model plant root biomass nor proportion of roots in the enriched quarter increased in the fertilizer treatment. Competition was probably higher in fertilized than in control plots judging by a 2-fold increase in death rate of model plants. However, greater proportion of model plants flowered in the treatment plots. Possible causes include a plastic response to the patch as well...

Vegetation changes in Czech lowland forests over the past decades Martin Kopecký ABSTRACT To explore decadal changes in plant species diversity and composition of typical lowland forests in the Czech Republic, I compared vegetation on plots sampled decades ago with vegetation on the same plots sampled recently. First I evaluated the robustness of the approach used in my thesis. In Chapter 1, we provided the first direct test of the effect of uncertainty in original plot location on results from vegetation resurvey. We found that temporal trends in vegetation diversity and composition were comparable between exactly relocated permanent and only approximately relocated semi-permanent plots. Therefore, we conclude that the resurvey of semi-permanent plots is robust to the uncertainty in original plot location. Then, we showed that vegetation in lowland oak forest shifted from species-rich communities of thermophilous forest toward species poorer communities of mesic forest (Chapter 2). The species typical for thermophilous oak forests and nationally endangered species suffered the most significant decline. We identified as the main driver behind these changes shift from traditional coppicing toward high forest management after WWII. Further, we explored the processes behind temporal shifts in species diversity...