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Detoxification of lignocellulose hydrolyzates
Vašíčková, Monika ; Pořízka, Jaromír (referee) ; Obruča, Stanislav (advisor)
The aim of this work was study of the detoxification of lignocellulose material hydrolysates and to investigate sawdust suitability as a substrate for microbial production of PHA by bacteria Burkholderia cepacia and Burkholderia sacchari. In the experimental part of the work the most suitable way of detoxification of model and real hydrolysate was studied. After that, detoxification methods used were evaluated. Criteria for evaluation were concentration of polyphenols as the most important microbial inhibitors and reduction saccharides as the main carbon substrate. Furthermore, fermentability of the hydrolysates was also tested by cultivation of two bacteria capable of PHA accumulation. Burkholderia sacchari demonstrated higher ability to accumulate PHA then Burkholderia cepacia. Then in the summary – most effective way for detoxification was ‚overliming‘. Major increase of PHB in biomass was obtained when Burkholderia sacchari was cultivated on media gained by application of overliming of real lignocellulose hydrolysate. However, total gains of PHB were more likely low and then sawdust can not be considered as a substrate for PHB production at industrial scale.
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Detoxification of coffee sediments by oxidation processes
Maňáková, Helena ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This bachelor thesis deals with the detoxification of used coffee grounds by the oxidation processes. The theoretical section describes the characterization of coffee beans and used coffee grounds. Furthermore, this section describes the valorisation of coffee grounds, especially its application as a fertilizer. The final part of the theoretical section focuses on the characterization of phenolic compounds, which are responsible for toxic properties of used coffee grounds, and analytical methods are described, which include UV–VIS spectrophotometry and high–performance liquid chromatography. The aim of the experimental part is the sample preparation, the application of the effective detoxification process and the analysis of the detoxificated used coffee grounds, focusing on the content of phenolic compounds. At the end of the experimental part, data processing is described. Three types of coffee grounds were used for determination of phenolic compounds: raw, defatted and the third type was defatted and simultaneously hydrolysed. High amounts of phenolic acids were identified in every sample, especially the gallic, ferulic, chlorogenic and caffeic acid. After an oxidizing agent was applied, positive detoxification of every sample of used coffee grounds was confirmed. For the most effective and most economical oxidation, a 1% oxidizing agent was chosen, which after a 10–minute oxidization efficiently reduced the content of the phenolic compound.
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Plant responses to combined arsenic and cadmium stress
Burešová, Andrea ; Mašková, Petra (advisor) ; Podlipná, Radka (referee)
Arsenic and cadmium are both non-essential, highly toxic and carcinogenic elements that often occur together in the environment. Given the frequent co-contamination of the environment, it is necessary to investigate both plant strategies for dealing with one metal(loid) and the mechanisms that lead to tolerance or, conversely, sensitivity in the presence of both elements. Simultaneous exposure to multiple toxic elements may lead to extensive plant damage, however it may also result in the increasing engagement and intensity of defence strategies. Contamination of the food chain through crops growing on contaminated soils is a major concern, one that poses a risk to both human and animal lives. The aim of this research field is to reduce accumulation and translocation to aboveground edible parts as much as possible, for example by understanding the mechanisms behind heavy metal accumulation and translocation, or by stabilising toxic elements in the soil, or by cleaning up contaminated soil. One method of clean-up is phytoremediation, which usually utilizes plants with high tolerance to toxic elements, called hyperaccumulators. The knowledge of how defence strategies and mechanisms are affected by the interaction of multiple elements is important for identifying plant species capable of activating...
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Lichens and (heavy) metals
Hrdinová, Aneta ; Peksa, Ondřej (advisor) ; Malíček, Jiří (referee)
My thesis is focused on liches and heavy metals. In first part includes the general characteristics of lichens, the short description of their biology, morphology and anatomy. The next part is focused on the characteristics of the methods of absorption of metals by lichens, their physiological effects on the body and the mechanisms of defense against the toxicity of metals lichens. The work includes the list of species of lichen, and their relationships to particular heavy metals. Key words: Lichens, heavy metals, metal tolerance, detoxification, copper
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Mechanism of uptake of heavy metals and organic compounds by plants
Berkyová, Petra ; Soudek, Petr (advisor) ; Petrová, Šárka (referee)
Heavy metals and organic compounds represent a great problem for environment. Therefore, attention is paid to the development of techniques for removing these pollutants from the sites of pollution. One of the possibilities is that heavy metals and organic compounds are removed from soil by using fytoremediation. Fytoremediation uses the ability of some plant species to uptake toxic compounds from soil and accumulate these compounds in its tissues. These plants are able to tolerate higher amounts of toxic compounds than it's usual because of the broad range of detoxification mechanisms, which are taking place in these plants. After the root uptake, heavy metals may be chelated by phytochelatins, metallothioneins or other chelators and subsequently stored in vacuoles. Transport of metal ions and metal complexes between cells compartments is mediated by many specific transport proteins. Detoxification mechanisms of organic compounds involve transfomation, conjugation and store of these compounds in plant tissues.
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Detoxification of coffee sediments by oxidation processes
Maňáková, Helena ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This bachelor thesis deals with the detoxification of used coffee grounds by the oxidation processes. The theoretical section describes the characterization of coffee beans and used coffee grounds. Furthermore, this section describes the valorisation of coffee grounds, especially its application as a fertilizer. The final part of the theoretical section focuses on the characterization of phenolic compounds, which are responsible for toxic properties of used coffee grounds, and analytical methods are described, which include UV–VIS spectrophotometry and high–performance liquid chromatography. The aim of the experimental part is the sample preparation, the application of the effective detoxification process and the analysis of the detoxificated used coffee grounds, focusing on the content of phenolic compounds. At the end of the experimental part, data processing is described. Three types of coffee grounds were used for determination of phenolic compounds: raw, defatted and the third type was defatted and simultaneously hydrolysed. High amounts of phenolic acids were identified in every sample, especially the gallic, ferulic, chlorogenic and caffeic acid. After an oxidizing agent was applied, positive detoxification of every sample of used coffee grounds was confirmed. For the most effective and most economical oxidation, a 1% oxidizing agent was chosen, which after a 10–minute oxidization efficiently reduced the content of the phenolic compound.
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Motivational work with clients in the Child and adolescent detoxification center.
Šainerová, Bohumila ; Večerka, Kazimír (advisor) ; Trávníčková, Ivana (referee)
The topic of this thesis is "Motivational work with a client in Child and adolescent detox center". The target of the theoretical part of this thesis is to describe motivational work with the client of the Child and adolescent detox center in the Hospital Sisters of Mercy of St. Charles Borromeo in Prague. The theoretical part is focused on general issue of drugs and addiction. Furthermore, there are described historical changes of the drug scene in our country in the 60s of the 20th century. Moreover, there are mentioned preventive measures against the emergence of the drug addiction. The detailed focus was given to the department of the Child and adoslescent detox center of the Hospital Sisters of Mercy of St. Charles Borromeo in Prague. In addtion, there are stated options of the treatment which can be used by the client during the stay in the Child and adolescent detox center in the Czech Republic. The aim of the practial part of the thesis is to analyse if and how the motivation for the change of the curent behaviour of the client varies during his or her visit in the Child and adolescent detox center. Furthermore, the analysis is focused on the casuistic description of personal and social background of the clients as well as the development of their drug issues during the treatment. The...
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Lichens and (heavy) metals
Hrdinová, Aneta ; Peksa, Ondřej (advisor) ; Malíček, Jiří (referee)
My thesis is focused on liches and heavy metals. In first part includes the general characteristics of lichens, the short description of their biology, morphology and anatomy. The next part is focused on the characteristics of the methods of absorption of metals by lichens, their physiological effects on the body and the mechanisms of defense against the toxicity of metals lichens. The work includes the list of species of lichen, and their relationships to particular heavy metals. Key words: Lichens, heavy metals, metal tolerance, detoxification, copper
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Detoxification of lignocellulose hydrolyzates
Vašíčková, Monika ; Pořízka, Jaromír (referee) ; Obruča, Stanislav (advisor)
The aim of this work was study of the detoxification of lignocellulose material hydrolysates and to investigate sawdust suitability as a substrate for microbial production of PHA by bacteria Burkholderia cepacia and Burkholderia sacchari. In the experimental part of the work the most suitable way of detoxification of model and real hydrolysate was studied. After that, detoxification methods used were evaluated. Criteria for evaluation were concentration of polyphenols as the most important microbial inhibitors and reduction saccharides as the main carbon substrate. Furthermore, fermentability of the hydrolysates was also tested by cultivation of two bacteria capable of PHA accumulation. Burkholderia sacchari demonstrated higher ability to accumulate PHA then Burkholderia cepacia. Then in the summary – most effective way for detoxification was ‚overliming‘. Major increase of PHB in biomass was obtained when Burkholderia sacchari was cultivated on media gained by application of overliming of real lignocellulose hydrolysate. However, total gains of PHB were more likely low and then sawdust can not be considered as a substrate for PHB production at industrial scale.
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How do plants manage to survive on toxic spoil-mining sites? Physiological and structural properties of plants on substrates with high As and Hg contents
Kovářová, Monika ; Albrechtová, Jana (advisor) ; Soudek, Petr (referee)
The heavy metals contamination of environment represents a worldwide problem lately. Heavy metals cause harmful effects not only to plants, but also to other organisms. Throught their acumulation in plant biomass, heavy metals enter a food chain and could negatively influence the human health. The impact of heavy metals on plants and their defence mechanisms against toxicity of heavy metals have been in focus of plant physiology and ecology research for decades. Importance of this topic arises from plant role in environment, ecosystem services and in human nutrition. Investigation in proces and mechanisms of heavy metal hyperacumulation in plants offer progress in fytoremediation and genetic engineering. The experiments on agricultural crops show how heavy metals enter the food chain and how they affect the crop yield. The aim of this thesis is to summarize information about heavy metals' effects on plants. The thesis is focused on arsenic and mercury, because the Czech Republic have also problem with heavy metals contamination and these two metals occur in high concentration in the spoil banks and soils adjacent to the lignite mining areas of Sokolovsko. The spoil banks with heavy metal content have to be revegatated, thus, the topic of their effect on plants is of high importance. In the first part of the...
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