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Laboratory scale batch studies were performed in order to determine the optimum growth conditions and diesel oil biodegradation ability of the selected strain isolated from petroleum hydrocarbons contaminated soil. These results were used to evaluate the potential of the selected strain for in situ application in PRB remediation technology.

This diploma thesis deals with the degradation of biologically degradable plastics. It focuses on the intensity of their degradation under the conditions of composting and on the influence of various factors on the colonization of biodegradable plastics by microorganisms. In the introduction of the theoretical part the key concepts of the field of biodegradable plastics are defined. The difference between plastics that are actually biodegradable and that are subject to only partial degradation is specified. Further the description of the process of biodegradation of polymers and the definition of biodegradability and compostability of polymer sis noted. At the end of theoretical part, the composting proces is described, with the enumeration of the phases and factors that influence the process. The practical part is devoted to the examination of the degradation of biologically degradable plastics in composting conditions both under a laboratory and under operating conditions. Laboratory experiment is complemented by the study of the influence of various factors on the process of biodegradation and on the intensity of colonization of biodegradable plastics by microorganisms.

The thesis aims to determine the actual degradability or biodegradability of selected samples of plastic bags in a controlled composting environment as well as the impact of biodegradable plastics on the final quality of compost. The theoretical part of the work describes the characteristics of synthetic polymers. The following chapter is devoted to biodegradable plastics and outlines their types, certification options as well as the normative support in the Czech Republic. In addition, it briefly characterizes the composting process itself and defines phytotoxicity. The practical part evaluates the experiment carried out on samples of plastic bags during the composting process and summarises the result of compost quality obtained by phytotoxicity testing.

This thesis deals with the possibilities of biodegradation of whey by the means of a mixed thermophilic aerobic bacterial culture of the Bacillus and Thermus genera. After protein had been removed, the whey was used as a medium for cultivation of the thermophilic microorganisms. The cultivations took their course in a fermentation unit and in the Erlenmayer flasks in a heated shaker in a whey medium. The bioengineering characteristics of the cultivation processes and the degree of biodegradation of the whey were evaluated. Scale of the whey biodegration was judged through the analytical characteristics – concentration of biomass, laktose and a chemical oxygen demand (COD). A decrease of CHSK was detected in all cultivations. Maximal reduction of CHSK was happend always in c. first half of each exponential phase growt, i.e. about 15 ± 3 % after first growth phase and sumarily about 62 ± 4 % after second growth phase.

The ability of the ligninolytic fungus Pleurotus ostreatusto degrade 4 pharmaceutical drugs and 5 compounds which are either used during drug manufacturing or are created as by-products was studied. These compounds were detected in groundwater near a drug manufacturing plant. The maximum concentration levels of the selected compounds in tested groundwater samples variedfrom0.23 µg/lto 227.87 µg/l apart from 1 compound which was not detected in any sample. The degradation efficiency of P. ostreatus was examined with individual compounds as well as with the mixture of all 9 compounds. When degrading individual compounds P. ostreatus lowered the initial concentration (10 mg/l) of 5 compounds by 62-100% after 14-day cultivation in malt extract-glucose medium. When degrading the compound mixture P. ostreatus lowered the initial concentration (2 mg/l of each compound) of 5 compounds by 50-100% after 14-day cultivation in malt extract-glucose medium. Acute toxicity tests with Vibrio fischeri suggest the formation of metabolites which are more toxic than the original compounds. The EC50 value for individual compounds during toxicity tests with Vibrio fischeri was 5.45-131.98 mg/l. Keywords:biodegradation, pharmaceuticals, ligninolytic fungi, Pleurotus ostreatus, groundwater, toxicity, Vibrio fischeri

10 ABSTRACT Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: PharmDr. Ondřej Holas, PhD. Student: Jiřina Blažková Title of thesis: A study of biodegradable polyesters based nanoparticles properties Nanoparticles (NPs) are particles with a diameter size ranging between 1 - 500 nm. They are preferably used as drug delivery systems or imaging systems. NPs are able to encapsulate both hydrophilic and hydrophobic drugs and also macromolecules such as peptides or mRNAs. The aim of this study was to specify selected properties of NPs prepared from poly (lactide-co-glycolide) polymer (PLGA) using polyvinyl alcohol as a surfactant. Nanoprecipitation was chosen as a preparation method. NPs were prepared from a branched PLGA copolymer and from a conventional linear PLGA polymer/oligomer. The main task was a stability study. The effect of the pH and the type of the used polymer of the nanoparticle suspension on the morphology of the nanoparticles was evaluated over one month period. The following parameters of nanoparticles with two model drugs (curcumin and procaine) were also monitored: encapsulation efficiency, drug loading and recovery yield. Dissolution tests were performer and the suitability of individual polymers for different types of drugs...

Screening of possibilities of deep subsurface microflora to decompose selected organic compounds Abstract The aim of the study is to test the deep microflora bacterial strains for their ability to grow in oily environment, aliphatic hydrocarbons and toluene were taken as examples of aromatic hydrocarbons and where the cultivation of selected strain, were produced for testing its growth and microbial activity of selected strains in conditions simulating soil conditions; assess the usability these strains in practical remediation of contamination by oil. This thesis deals with the evaluation of possible use of selected strains of deep microflora for oil decomposition. It is evident, that some groups of microorganisms living in the Tertiary claystones at depths of 30-450 m below the surface are the biodegradable fossil organic matter type of kerogen. Chemical findings indicate that, this organic matter consists of various lengths of aliphatic chains, and thus the assumption that microorganisms decomposing kerogen might be able to disassemble oil and petroleum products. The findings of our experiment indicate that benzene and toluene, as well as kerogen are highly resistant to organic compounds and evidence of microbial degradation are rare. Utilization of oil as representative aliphatic compounds is better...

Polychlorinated biphenyls (PCBs) are chlorinated organic compounds, which belong to persistent organic pollutants and exhibit various modes of toxic action, including mutagenicity, carcinogenicity, and endocrine disruption. PCBs were manufactured during the 20th century in many countries and extensively used due to their advantageous physicochemical properties. PCBs mostly served as insulating liquids in electrical equipment; however, they were also utilized in many open applications. Despite the worldwide ban on PCB manufacture imposed at the end of the 20th century, the contamination of the environment persists to this day as a result of their recalcitrance. Moreover, PCBs are still being inadvertently produced during many industrial activities. Because of their stability, the breakdown of PCBs in nature is extremely slow. This dissertation thesis focuses on the study of PCB biodegradation by ligninolytic fungi. This group of microorganisms belongs to the most promising, especially in regard to the degradation of organic pollutants. The biodegradation mechanism of PCBs was studied in vitro, including the identification of degradation intermediates. Laccase, an enzyme expressed by the oyster mushroom (strain Pleurotus ostreatus 3004), was able to degrade hydroxylated PCBs. In addition, chlorinated...