National Repository of Grey Literature 47 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
The study of vertical mobility of heavy metals and their transfer to mushrooms
Jurnečka, Roman ; Doležalová Weissmannová, Helena (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of contamination of forest soils and edible mushrooms with lead, cadmium, copper and zinc in the Jeseníky Mountains, specifically in the Domašov and Vápenná forests. Sampling took place at 12 localities, divided into spruce and beech stands. Atomic absorption spectrometry AAS ContrAA 800D was chosen to determine the content of selected heavy metals. Based on the measured values of the concentrations of the studied metals and other soil properties, dependences were created to determine the vertical mobility of selected metals in the soil profile. Vertical mobility depends on the physico-chemical properties of the soil (pH, C and S content). The dependence of the content of selected heavy metals in the soil on the pH value of the soil was found. In the case of lead, the sorption capacity of the soil organic component was confirmed. The risk and above-limit content of Pb, Cd and Cu was found on the yellow-boletus mushroom. Cadmium shows the highest bioavailability. Lead was evaluated as the element with the lowest mobility.
Persistent Organic Pollutants in the Environment of the Southern Moravia Region
Lána, Radim ; Kráčmar, Stanislav (referee) ; Večeřa, Zbyněk (referee) ; Hajšlová, Jana (referee) ; Vávrová, Milada (advisor)
Byla provedena studie bioakumulace POP v potravním řetězci a historických trendů hladin POP v sedimentech Brněnské přehrady. Současné úrovně kontaminantů byly stanoveny v jelci tloušti z řeky Svratky a rovněž byla posouzena hygienická kvalita ryb z rekreačního rybolovu. Současné úrovně POP v terestrickém ekosystému byly posouzeny pomocí analýz jehličí jako přirozeného indikátoru znečištění. Studium jedinců tří druhů dravých ptáků z ČR bylo zaměřeno na zhodnocení kontaminace těchto vrcholných predátorů POP. S pomocí analýz vybraných druhů ryb ze Záhlinických rybníků byl rovněž studován proces bioakumulace. Posouzení parametrů dvou moderních extrakčních technik a jejich využitelnosti pro izolaci POP z různých matric bylo námětem poslední části dizertace.
Detection of luminescent nanoparticles in plants by laser spectroscopy
Střítežská, Sára ; Novotný,, Karel (referee) ; Modlitbová, Pavlína (advisor)
This diploma thesis deals with evaluation of toxicity and bioaccumulation of photon-upconversion nanoparticles (UCNPs) in model plant maize (Zea mays). Lanthanide-doped UCNPs with different composition and size were tested in three different concentrations in this work. The exposure took place for 168 hours. Toxicity was assessed based on four macroscopic toxicological endpoints (mortality, the length of belowground part of the plants, the length of aboveground part of the plants and whole plants length). Spatial distribution of elements yttrium, ytterbium, erbium and gadolinium in model plants was determined using laser induced breakdown spectroscopy with spatial resolution of 100 m and 26 m. Distribution of UCNPs in plants was further studied with photon-upconversion microscanning with spatial resolution of 40 m. Stability of UCNPs during and after the plant exposure was also discussed in this thesis.
Production, Characterization and Utilization of the Biomass from Various Sources
Gojkovic, Živan ; Vávrová, Milada (referee) ; Čertík, Milan (referee) ; Márová, Ivana (advisor)
Úprava biomasy je jedním z nejdůležitějších problémů v moderních přírodních vědách, protože je základní kategorií týkající se zemědělství, potravinářství, ekologie, zpracování odpadu a biotechnologie. Ať už živočišného, rostlinného nebo mikrobiálního původu, biomasa představuje obrovský zdroj surovin jako potravin, čistých chemikálií, bioaktivních molekul atd., jejichž izolace, charakterizace a formulace může vést k zajímavým novým produktům určeným pro lidskou spotřebu, nebo jako nový materiál v biomedicíně. Předložená studie byla zaměřena na výzkum dvou druhů biomasy - kuřecí kůže jako zdroje kolagenu t a biomasy mikrořasy Chlorella sorokiniana obohacené selenomethioninem (SeMet). V první části práce byl z kuřecí kůže izolován, identifikován a charakterizován kolagen typu I. Molekulární vlastnosti kuřecího kolagenu byly analyzovány a srovnány s jinými kolageny z živočišných kůží. Pro molekulární charakterizaci kolagenu byla použita viskosimetrie a ultrazvuková spektroskopie. Ultrazvukovou spektroskopií bylo zjištěno, že disagregace a zkapalňování hovězího kolagenu začíná při teplotě 40 °C, zatímco u kuřecího kolagenu začíná až při 50 °C. Viskosimetrie dále potvrdila vyšší tepelnou stabilitu kolagenu z kuřecí kůže, jeho denaturační teplota byla 50 °C, což je rovněž o deset stupňů více než u hovězího kolagenu. Kuřecí kolagen obsahuje dvakrát vyšší množství lysinu, což poskytuje tepelnou stabilitu kolagenu. Na základě získaných výsledků lze říci, že vzhledem ke své vysoké tepelné stabilitě a vhodnému aminokyselinovému složení, kuřecí kůže může být použita jako alternativní zdroj kolagenu typu I s aplikacemi v potravinářském průmyslu a biomedicíně. Druhá část práce byla zaměřena na obohacení biomasy zelené mikrořasy C. sorokiniana selenomethioninem. Experimentální část byla provedena v Laboratoři biotechnologie řas na Univerzitě Huelva ve Španělsku. Cílem první části experimentů bylo studovat vliv selenu na životaschopnost řas, morfologii buněk a akumulaci SeMet v biomase mikrořasy kultivované v dávkových kulturách. Subletální koncentrace Se v živném médiu, 40 mgL-1 (212 M), snížila rychlost růstu o 25 % ve srovnání s kontrolní kulturou. Hodnota EC50 45 mgL-1 (238,2 M) byla stanovena pro selenan. Ultrastrukturální studie ukazovaly na strukturální změny chloroplastu (granulární stroma, redukce thylakoid). Elektroforéza proteinů z biomasy mikrořasy ukazuje, že Se ovlivňuje expresi genu enzymu Rubisco. C. sorokiniana byla schopna akumulovat až 140 mgkg-1 SeMet během 120 h kultivace. Další část experimentální práce byla zaměřena na obohacování biomasy mikrořasy C. sorokiniana selenomethioninem během kontinuální kultivace s použitím 2,2 L bioreaktoru v kultivačním médiu s přídavkem koncentrace selenu v rozmezí od 5 do 50 mgL-1. C. sorokiniana rostla stejně ve všech testovaných koncentracích selenu kromě koncentrace 50 mgL1, která byla již po krátké době kultivace letální. Během kontinuální kultivace se 40 mgL-1 selenu, bylo získáno maximálně 246 gL-1 selenomethioninu denně. Výsledky ukazují, že kultivace v dávkových kulturách a dlouhodobá kontinuální kultivace mikrořasy C. sorokiniana pro získaní biomasy obohacené SeMet je možná pečlivým výběrem podmínek kultivace a subletálních koncentrací selenu v živném médiu.
Study of metals bioaccumulation by the aquatic moss Fontinalis antipyretica
Jaskowiecová, Lenka ; Hekera,, Petr (referee) ; Diviš, Pavel (advisor)
This diploma thesis is focused on determination of bioavailable cadmium in natural waters. Thesis is devided to two parts-laboratory study in model solution and experiments in real surface water system. During the laboratory experiments the accumulation and release constants of cadmium by aquatic moss Fontinalis antipyretica were determined. In Morava river experiment this aquatic moss was used to determine bioavailable fraction of cadmium and the moss bag technique were compared with another methods for phytotoxic metals determination.
Use of selected toxicity tests on organisms Eisenia fetida in assessing ecosystem contamination by selected drugs.
Kašpárková, Petra ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Constantly increasing consumption of drugs leads to the increase of the concentration of residues in various environmental compartments. For this reason the drug residues are nowadays classified as significant environmental contaminants. The drug residues enter the soil along with the application of sewage sludge either as a fertilizer or during fertilizing by animal excrements excreted after drug administration, eventually by direct contamination from treated grazing animals. The presence of these substances in soil has got negative impact on the sensitive soil ecosystem. The diploma thesis aims to evaluation of possible soil contamination with selected drugs through ecotoxicity tests. For this purpose sulfonamide chemotherapeutic agents, which are often used in veterinary medicine, were chosen, specifically sulfamethoxazole and sulfamethazin. Eartworms (Lumbricus) were selected as suitable test representative soil organism. In the experimantal part of this work the avoidance test according to ISO 17512-1 and modified bioaccumulation test according to OECD 317 methodology were performed. Bioaccumulation substances in oligochaetes, for which the artificial soil was prepared according to OECD 207 methodology, which was subsequently contaminated with above specified drugs. Although according to the results of determination of these substances there is no significant bioaccumulation in eartworms‘ tissue, these organisms are very responsive to the presence of contaminants in the soil environment. This is evident from the results of avoidance tests.
The study of contamination of forested areas of the Czech Republic by mercury
Trávníčková, Gabriela ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of mercury in the environment. It focuses on determining the concentration of total mercury in edible mushrooms and in the soil in 12 localities in the Jeseníky Mountains. A single-purpose absorption spectrometer AMA 254 was used to determine the mercury content. The sites where sampling took place were divided into 6 sites with spruce stand and 6 sites with beech stand. No relationship was found between the type of stand and the amount of accumulated mercury in the mushrooms. On a representative sample of yellow-boletus mushrooms found in each locality, it was found that the higher the amount of mercury in the mushroom, the lower the amount of mercury in the soil. The fungi are therefore able to accumulate mercury from the environment. Thus, they can become a potential source of intoxication when ingested. The mobility of heavy metals in the soils depends on many soil properties (pH, carbon and sulfur content). Metals form more soluble compounds in lower pH environments. The soil pH was very low and the lower the soil pH, the higher mercury concentration in the soil. This fact could be supported by acid fallout. The relationship between the mercury content and the carbon content of the soil confirmed that carbon has the ability to bind mercury. The higher the amount of carbon in the soil, the higher the amount of mercury.
Cycling of mercury and mercury species in the environment
Finsterlová, Hana ; Diviš, Pavel (referee) ; Dočekalová, Hana (advisor)
This bachelor’s thesis deals with the role of mercury in an environment. It summarizes informations about properties of mercury and its species. The thesis is engaged in the presence of mercury in atmosphere, water, soil and sediments. It deals with individual mercury intakes into the environment, anthropogenic or natural, and it follows transport of mercury between individual components of environment. Part of this thesis is given to the accumulation of mercury and mercury species into plants and organisms. It points out the toxicity of mercury, mercury species, and their effect to human organism. In the last chapter there is a resume and description of the instrumantal methods, which are commonly used for determination mercury and its compounds.
Detection of heavy metals in hard tissues by laser-induced breakdown spectroscopy
Konečná, Anna ; Novotný, Karel (referee) ; Pořízka, Pavel (advisor)
This master thesis deals with the detection of heavy metals bioaccumulated in hard tissues by laser-induced breakdown spectroscopy (LIBS). As model samples, murine mandibles and femurs of animals exposed to lead oxide or cadmium oxide nanoparticles were used. The exposure of animals lasted for 6 or 7 weeks. Control group of animals was exposed only to air for a reference. The distribution of biogenic elements and contaminants was determined by mapping the samples' surface using LIBS with a spatial resolution of 30 and 100 µm. The second part of the work focused on the possibility of using the method LIBS for quantitative analysis. Samples of hydroxyapatite standards were prepared as reference material. By their analysis a calibration curve was constructed, and the limits of detection and quantification were determined. Furthermore, a model for prediction of heavy metal concentration by calculation from the calibration curve was presented.
The Study of Distribution of Halogenated Diphenylethers to Parts of Environment
Hroch, Martin ; Hajšlová, Jana (referee) ; Kráčmar, Stanislav (referee) ; Šucman, Emanuel (referee) ; Vávrová, Milada (advisor)
In recent years considerable attention is paid to problems of brominated flame retardants (BFR's – Brominated Flame retardants), which are a diverse group of organic compounds. Even in the recent past have been the most often represented group particularly polybrominated diphenyl ethers (PBDEs), which have found wide use in many industrial sectors. The reason of aplication of these substances is the ability to slow down the combustion process and reduce the risk of ignition by the excessive heating of material. On the other hand, serious concerns about the use of PBDEs was added. The most serious trouble is particular their possible to release from consumer products during their normal use, toxicity and high persistence in parts of environment. Some of these contaminants are more characterized by a high degree of accumulation in biological systems. In this work by several sub-studies the issue of assessment the level of pollution of the aquatic ecosystem of selected localities of the Czech Republic just PBDEs was addressed. One of objectives was monitored the situation of breeding ponds near the village Záhlinice in Central Moravia. Here was assessed level of contamination in fish and birds as two consecutive segments of food chain. The obtained results largely confirmed the assumption that with increasing trophic level of organisms leads to bioaccumulation and thus also higher findings. For comparison, the capture of fish and birds in other localities of the CR was also implemented. In Bartošovice and Hustopeče nad Becvou levels at the buzzard and heron were detected as comparable. The cormorants of the order higher levels of PBDEs were found. Further were also evaluated levels of PBDEs detected in individuals of bioindicator kind of chub caught in two locations on the river Svratka in spring and autumn. Findings of PBDE in muscle, skin and intestines were compared. The obtained results show that between tissues and sites wasn’t significant variability respectively and the findings of controlled substances are practically comparable. With aim to determine the dependence of the concentration of PBDEs in organisms on the length of the river was conducted monitoring of Vír and Brno water reservoirs. In both locations was main monitored kind of bream, which was completed by the other species. The results of the analysis indicate a higher total concentration at the lower part of river Svratka. Differences were also the distribution of individual congeners in both sampling locations. For monitoring of terrestrial system contamination levels of PBDEs has been selected several types of plant bioindicators. These are mainly pine needles (Scots pine, Eastern white pine, Silver fir, Blue spruce) collected from different localities of the Czech Republic. Other matrices were chosen roughages (Common wheat, Naked barley, Alfalfa wheat, Red clover) and oilseeds (Rapeseed) from the Novy Jicin, where Agriculture plant school of the University of Veterinary and Pharmaceutical Sciences Brno. Detected values of PBDE concentrations were very low, generally ranged at the detection limits of the analytical method.

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