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21	Vliv jednotlivých fázi výrobního procesu Lignamonu a jejich vzájemných interakcí na výslednou odolnost vůči dřevokazným houbám Nevrlý, Ondřej January 2018 (has links) In this work is discussed about material Lignamon, which has been industrially produced in the former Czechoslovakia since the 1970s. The production of this material, mainly from beechwood, combines plasticization with gaseous ammonia, densification of material by hydraulic press and heat stabilization at 180 ° C. The aim of this work is to determine the effect of these processes on the resulting resistance to wood-decaying fungi. Lignamon has a very high resistance to wood-decaying fungi and is classified as very durable according to EN 350 - 1. For each phase of the Lignamon process, samples were produced to best illustrate the changes that take place during the given phase in the wood. In particular, sample sets treated with ammonia gas, densified samples, heat-treated samples, and samples on which a combination of ammonia gas impregnation and thermal modification were performed. The resistance to wood-decaying fungi have been tested according to EN 113, including a set of Lignamon samples. The results of this test were statistically evaluated and it was found that ammonia treatment has the greatest influence on the durability of Lignamon, as well as the heat treatment and not so significantly densification. Individually, however, none of these modifications cause wood resistance to wood-decaying fungi as their combination in the production process of Lignamon.
22	Profil lakasové aktivity v kulturách houby Trametes versicolor během degradace endokrinně disruptivní látky Delor 103 / Laccase activity profiling in Trametes versicolor cultures degrading endocrine-disrupting compound Delor 103 Plačková, Martina January 2011 (has links) In this work endocrine disrupting potential of Delor 103, a commercial mixture of PCB congeners, was studied along with its effect on production of laccase by the ligninolytic fungus Trametes versicolor. Using a gene-reporter yeast assay for evaluation of hormonal activity Delor 103 showed an androgenic activity with an EC50 value of 2.29. 10-2 mg/l. Chlorbenzoic acids, Delor 103 potential metabolites resulting from microbial degradation, displayed on the other hand an estrogenic activity, indicating possible changes in hormonal activity of Delor 103 during its microbial degradation. The addition of Delor 103 to mineral medium T. versicolor cultures resulted in an up to 257times higher laccase activities detected in fungal cultures. Delor 103 induced enzymes showed different pI values from those of control cultures. In a complex malt-extract glucose medium (MEG) the stimulation effect of Delor 103 was kept down. Further, the production of laccase and synthesis of different pI forms depended strongly on the growth phase of fungal cultures. Exponencially growing cultures of T. versicolor were able to produce up to 7 different pI forms of laccase in responce to Delor 103 whereas stationary cultures produced only 4 enzyme forms with higher pI values. Stimulation of laccase activities in T. versicolor,...
23	Occurrence and fate of pharmaceuticals in wastewater treatment processes Jelić, Aleksandra 21 December 2012 (has links) Pharmaceuticals have been detected in natural waters for more than forty years, but with improvements in sample preparation procedures and analytical instrumentation, the number of scientific publications on the issue has increased significantly. Even though the concentration of pharmaceutical residues in surface and drinking water is not critical for human health according to the present level of knowledge, the consequences for the environment are not clear. Wastewater treatment plants (WWTPs) have been identified as the primary route of pharmaceuticals to the environment, with households as the major source point for most of the over-the-counter and prescription drugs. In this thesis, the first aim was to study the occurrence, fate and removal of 43 pharmaceuticals during conventional wastewater treatment. The target compounds were selected on the basis of their high consumption in Spain or/and frequently reported detection in wastewaters and the possibility to be analyzed under the same experimental conditions. They belong to different therapeutic classes, i.e. nonsteroidal anti-inflammatory agents and analgesics, lipid modifying agents, psycholeptic and antiepileptic drugs, beta-blocking agents, beta-2-adrenoreceptor agonists, H2-receptor antagonists, antibiotics, angiotensin converting enzyme agents, diuretics and antidiabetic drugs. A wide variation in removal efficiencies was observed even for individual compounds, and across therapeutic classes and treatment processes, without clear conclusion on the removal of any particular compound. According to mass balance calculations and estimated partition coefficients, the loss of the selected pharmaceuticals during biological wastewater treatment can be fully attributed to biodegradation/biotransformation. None of the studied compounds was entirely biodegraded and/or transformed during biological wastewater treatment, but the measured concentrations were below the levels of concern according to available toxicity data. Conventional WWTPs cannot be expected to be the only mechanism for controlling the entry of pharmaceuticals into the environment because they were neither designed nor can provide their complete removal. Therefore, the challenge is to look for solutions that would be the most economical and effective means of preventing further pollution of natural waters by pharmaceuticals. More appropriate management of sewage waters before they enter treatment plants as well as a stricter control of effluent discharges, along with an in-depth investigation on the development of new designs and strategies for the improvement of existing wastewater treatments should be considered. In light of this, as the second objective of this thesis, alternative approaches for the removal of the antiepileptic carbamazepine (CBZ) were studied in aqueous media in two laboratory scale experiments: a) biodegradation using white rot fungus T. versicolor in an air-pulsed fluidized bioreactor operated in batch and continuous modes, and b) advanced oxidation using TiO2-heterogeneous photocatalysis under simulated solar and UV-A irradiation, and under the combined use of ultrasound and UV-A irradiation (sonophotocatalysis). We selected CBZ as a representative example of compounds that are found to be refractory to biological treatment and ubiquitous in various environmental matrices. Both, the fungal and UVA-driven TiO2-photocatalytic treatments, very different in their nature, have been shown to be very effective in degrading carbamazepine in aqueous media. The fungal treatment resulted in average removals of 54 and 96% in batch and continuous reactor, respectively. Acute toxicity test using the bioluminescent marine bacterium Vibrio fischeri showed a decrease in toxicity during the treatment in both types of bioreactor. In the other study, initial CBZ concentrations were reduced for 95% during 120 min of the UV-driven photocatalytic experiment and sonophotocatalysis, while only 10 % of CBZ was photodegraded during under solar irradiation. A slight increase in toxicity in Daphnia magna acute toxicity testing was observed over the time-course of the photocatalytic experiments, which can be associated with the formation of transformation products of CBZ. Ultraperformance liquid chromatography coupled to a quadrupole-time-of-flight mass spectrometry was used for a tentative identification of the transformation products of CBZ formed during the performed experiments. Most of the tentatively identified intermediates exhibited only slight modifications of the CBZ molecular structure. The fungal as well as the photocatalytic processes yielded oxygenated transformation products. In the biological treatment using T. versicolor, transformation products were formed by enzymatic epoxidation and hydroxylation of seven-membered heterocyclic ring of the carbamazepine molecule. During the photocatalytic experiments, CBZ-related transformation products emerged from hydroxylation and further oxidation of different parts of the molecule of carbamazepine. The generated transformation products appeared to be more persistent than their parent compound, as they were present, although at low concentration, until the end of the experiments. The results of the thesis contribute to a better understanding of a) the magnitude of the selected pharmaceuticals that reach the environment through the wastewater and sludge discharge, b) the efficiency of typical conventional wastewater treatment plants regarding the removal of these compounds from raw wastewater, and c) possible developments of alternative technologies for their enhanced elimination. / Desde hace más de cuarenta años se ha detectado la presencia de fármacos en el ciclo de aguas, sobre todo debido a los avances en la química analítica que han permitido el desarrollo de nuevas metodologías analíticas para la determinación de estos compuestos de modo fiable y a bajas concentraciones. Las estaciones depuradoras de aguas residuales (EDARs) han sido identificadas como la ruta principal de entrada de fármacos de origen humano en el medioambiente. Por tanto, el principal objetivo de esta tesis ha sido el estudio de la presencia, destino y eliminación de 43 fármacos seleccionados, durante el tratamiento convencional realizado en las EDARs. Los compuestos estudiados fueron seleccionados en base a los índices de consumo en España, a la frecuencia de detección en aguas residuales y además en base a la posibilidad de ser analizados bajo las mismas condiciones experimentales. Estos compuestos pertenecen a diferentes clases terapéuticas, i.e. antiinflamatorios no esteroideos , los agentes que reducen los lípidos séricos, ansiolíticos y antiepilépticos, los agentes bloqueadores beta-adrenérgicos, agonistas β2 adrenérgico, antagonistas H2 , antibióticos, inhibidores de la enzima convertidora de angiotensina, diuréticos y antidiabéticos. Para el análisis cuantitativo se utilizó la cromatografía de líquidos acoplada a espectrometría de masas en tándem (LC-MS/MS), empleando un sistema híbrido triple quadrupolo/trampa de iones lineal. Como segundo objetivo hemos considerado evaluar tratamientos avanzados alternativos al tratamiento convencional para la eliminación de un fármaco antiepiléptico, la carbamazepina, uno de los compuestos más recalcitrantes al tratamiento biológico convencional. Se procedió a estudiar su degradación en medio acuoso mediante dos procedimientos a escala laboratorio: a) biodegradación utilizando el hongo ligninolitico Trametes Versicolor en un reactor fluidizado por pulsos de aire operando en modo batch y continuo, y b) oxidación avanzada mediante un tratamiento fotocatalitico en presencia de TiO2 bajo irradiación UV-A y solar, y aplicando la radiación UV en combinación con ultrasonidos (sonofotocatálisis). Para la evaluación de los tratamientos alternativos, se identificaron los productos de transformación de la carbamazepina, y se evaluó la toxicidad de las muestras tratadas. Se utilizó la LC-MS/MS con analizador de tipo cuadrupolo-tiempo de vuelo. También se evaluó la toxicidad de las muestras tratadas. Medicaments Medicamentos Drugs Aigües residuals Aguas residuales Sewage Llots de depuradora Lodos de depuradora Sewage sludge Fotocatàlisi Fotocatálisis Photocatalysis "Trametes versicolor" Ciències Experimentals i Matemàtiques 543
24	Fungal Pigment Formation in Wood Substrate Tudor, Daniela 14 January 2014 (has links) A number of fungi produce spalted wood, which is characterized by accumulation of black pigment in fine demarcation lines, often accompanied by discoloration or staining on the wood fibers. Specific spalting fungi were identified by molecular analysis. From a total of 19 isolates and 140 clones studied, 11 fungal species were identified. The two Chlorociboria species from North America were investigated and their anamorphs were unambiguously identified for the first time. Fungal pigment formation under the influence of moisture content and pH variation was investigated in sugar maple, American beech and agar inoculated with spalting fungi. Maximum pigment production occurred at treatment with pH 4.5 for sugar maple and beech inoculated with Trametes versicolor. Xylaria polymorpha produced external pigmentation in beech treated with buffer at pH 5 and sugar maple at pH 4.5. Fungal pigmentation by Trametes versicolor and Xylaria polymorpha was stimulated at low moisture content in both wood species tested. Melanin production by Inonotus hispidus and Polyporus squamosus was stimulated above 22-28% and 34-38% moisture content in beech and in sugar maple respectively. Fomes fomentarius and Polyporus brumalis produced maximum pigmentation in beech at 26 - 41% and in sugar maple at 59 - 96% moisture content. The variation of the moisture content and pH values of wood substrates can stimulate the intensity of pigmentation of specific fungi in wood. To investigate melanin synthesis from a variety of melanin precursors, experimental research on three spalting fungi tested their reaction to catechol and L-Dopa melanin precursors in wood and agar substrate. The results indicate multiple biosynthesis pathways for melanin assembly in Trametes versicolor, Xylaria polymorha and Inonotus hispidus, and catechol produced most pigmentation in all spalting fungi investigated. Microscopic analysis by light, fluorescence, electron and confocal microscopy also indicates a bi- or multi-modal activity of melanin production and assembly by several spalting fungi. Possible variations of melanin assembly were identified based on fungal and wood species. Immunofluorescence and immunogold labelling with Mab 6D2 melanin antibody confirmed the melanin nature of the pigments produced by Oxyporus populinus, Trametes versicolor, Xylaria polymorpha, Fomes fomentarius, and Inonotus hispidus. spalting wood degradation staining fungi white rot fungi fungal melanin fungal pigment Trametes versicolor Xylaria plymorpha Chlorociboria Scytalidium cuboideum Wood technology 0746 Microbiology 0410
25	Fungal Pigment Formation in Wood Substrate Tudor, Daniela 14 January 2014 (has links) A number of fungi produce spalted wood, which is characterized by accumulation of black pigment in fine demarcation lines, often accompanied by discoloration or staining on the wood fibers. Specific spalting fungi were identified by molecular analysis. From a total of 19 isolates and 140 clones studied, 11 fungal species were identified. The two Chlorociboria species from North America were investigated and their anamorphs were unambiguously identified for the first time. Fungal pigment formation under the influence of moisture content and pH variation was investigated in sugar maple, American beech and agar inoculated with spalting fungi. Maximum pigment production occurred at treatment with pH 4.5 for sugar maple and beech inoculated with Trametes versicolor. Xylaria polymorpha produced external pigmentation in beech treated with buffer at pH 5 and sugar maple at pH 4.5. Fungal pigmentation by Trametes versicolor and Xylaria polymorpha was stimulated at low moisture content in both wood species tested. Melanin production by Inonotus hispidus and Polyporus squamosus was stimulated above 22-28% and 34-38% moisture content in beech and in sugar maple respectively. Fomes fomentarius and Polyporus brumalis produced maximum pigmentation in beech at 26 - 41% and in sugar maple at 59 - 96% moisture content. The variation of the moisture content and pH values of wood substrates can stimulate the intensity of pigmentation of specific fungi in wood. To investigate melanin synthesis from a variety of melanin precursors, experimental research on three spalting fungi tested their reaction to catechol and L-Dopa melanin precursors in wood and agar substrate. The results indicate multiple biosynthesis pathways for melanin assembly in Trametes versicolor, Xylaria polymorha and Inonotus hispidus, and catechol produced most pigmentation in all spalting fungi investigated. Microscopic analysis by light, fluorescence, electron and confocal microscopy also indicates a bi- or multi-modal activity of melanin production and assembly by several spalting fungi. Possible variations of melanin assembly were identified based on fungal and wood species. Immunofluorescence and immunogold labelling with Mab 6D2 melanin antibody confirmed the melanin nature of the pigments produced by Oxyporus populinus, Trametes versicolor, Xylaria polymorpha, Fomes fomentarius, and Inonotus hispidus. spalting wood degradation staining fungi white rot fungi fungal melanin fungal pigment Trametes versicolor Xylaria plymorpha Chlorociboria Scytalidium cuboideum Wood technology 0746 Microbiology 0410
26	Decolorization of an azo and anthraquinone textile dye by a mixture of living and non-living Trametes versicolor fungus Dykstra, Christine M. 01 May 2011 (has links) Wastewater from the textile industry is difficult to treat effectively due to the prevalent use and wide variety of synthetic dyes that are resistant to conventional treatment methods. White-rot fungi, such as Trametes versicolor, have been found to be effective in decolorizing many of these synthetic dyes and current research is focusing on their application to wastewater treatment. Although numerous studies have been conducted on the ability of both living and nonliving Trametes versicolor to separately decolorize textile dyes, no studies were found to have investigated the use of a mixture of live and dead fungus for decolorization. This study explored potential interactions between live and dead, autoclaved Trametes versicolor biomass in a mixed system by utilizing a series of batch tests with two structurally different synthetic textile dyes. Samples were analyzed by spectrophotometer and compared with controls to determine the effect of any interactions on decolorization. The results of this study indicate that an interaction between living and nonliving biomass occurred that affected the specific dye removal for both Reactive Blue 19, an anthraquinone textile dye, and Reactive Orange 16, an azo textile dye. This interaction was seen to improve the specific dye removal during the first 10-46 hours of experimentation but then diminish the specific dye removal after this period. This effect could be due to hydrophobins, which are surface-active proteins excreted by live fungi that may alter hydrophobicity. Additionally, the presence of adsorptive dead biomass could affect dye contact with degrading enzymes released from the live fungus. By expanding current knowledge of the interactions that take place in a fungal bioreactor and their effect on textile dye decolorization, this research aims to inspire more effective and less costly bioreactor designs for the treatment of textile wastewater. Environmental Engineering
27	Biological attack of acetylated wood / Biologischer Angriff von acetyliertem Holz Mohebby, Behbood 03 May 2003 (has links) No description available. 500 Naturwissenschaften allgemein Forest Sciences and Forest Ecology Acetylierung Buche Kiefer Gewichts- und MoE(dyn)-Verlust Boderversuch Feldversuch Basidiomycet Moderfäule bakterieller Abbau Weissfäule Braunfäule Trametes versicolor Poria placenta Lichtmikroskopie acetylation beech Scots pine mass and MOEdyn loss soil bed test field test basidiomycete soft rot bacterial degradation white rot brown rot Trametes versicolor Poria placenta light microscopy 48.46 Holz Y
28	Možnosti eliminace sulfonamidů z vodního ekosystému / Possibilities of elimination of sulfonamides from the aquatic ecosystem Suková, Petra January 2018 (has links) This diploma thesis focuses on the determination of sulfonamide antibiotics especially the possibility of elimination of these substances from the aquatic ecosystem. Nowadays, environmental contamination of the pharmaceuticals and their residues is a serious concern. Main sources of this contamination are wastewater treatment plants (WWTPs), where these compounds are not effectively removed by contemporary conventional technology. For this reason, new methods are being developed and tested that could eliminate the number of contaminants entering the environment in this way. There is a possibility to use the potential of the enzymatic system of wood-decay fungi, especially white rot fungi. Six representatives of sulfonamide antibiotics were selected and isolated from the aquatic matrix via solid phase extraction. The final identification and quantification method was high performance liquid chromatography with mass spectrometric detection. Monitoring of the concentration level of selected sulfonamide antibiotics at the inflow and effluent at the Brno-Modřice WWTP was carried out weekly. Moreover, the effectiveness of elimination of selected antibiotics from the aquatic ecosystem by the use of Trametes versicolor wood-decay fungi cultured on a suitable carrier was verified.
29	Remoção do corante FD&C azul nº 2 Indigotina em água com uso de fungos de decomposição branca e processo de filtração lenta: avaliação em escala piloto / Remove the dye FD & C Blue No. 2 indigo in water use fungal decay and white slow filtration process: evaluation in pilot scale LOPES, Maria Margareth Gonçalves 04 August 2008 (has links) Made available in DSpace on 2014-07-29T15:01:40Z (GMT). No. of bitstreams: 1 maria margareth goncalves.pdf: 3073051 bytes, checksum: a405b4aae069912b1212db181d1858f8 (MD5) Previous issue date: 2008-08-04 / Industrial activities are constantly producing wastes such as dyes which are usually found in the industrial effluents and constitutes a environmental problem due its toxicity and inadequate disposal. The use of fungi, in particular the white-rot fungus, have been found to be efficient for biodegrading these compounds. In addition, slow sand filtration have been reported to be the most efficient unit filtration processes to improve the physical, biological and chemical quality of potable water. The objective of this work was to investigate the removal efficiency of the dye FD&C azul Nº 2 Indigotina, by the use of the Trametes versicolor fungus combined with slow sand filtration. Two laboratory-scale filter columns of 0.08 m diameter and 0.90 m sand media depth were used to investigate the process performance. One slow sand filter, FLA, was applied in combination with the Trametes versicolor fungus, while the FLB was used as control. Three methodologies for the fungi growth were used. The results showed that the slow sand filtration is a prominent process for the removal of the dye FD&C azul nº 2 Indigotina when used in combination with the Trametes versicolor fungus. A maximum removal of 95% was found when the filter was inoculated with fungi grown on Petri dish. The average dye removal when the increased fungi biomass was inoculated to the filter was 70%. This result suggests that the filter performance increased when the fungus was inoculated with fungi grown on Petri dish. In addition, head loss was found to be higher in the FLA filter than in the FLA (control), indicating that the fungi biomass contributes to the head loss development. / Nas atividades industriais geradoras de resíduos os corantes são amplamente encontrados nos efluentes, quase sempre, constituindo um problema de ordem ambiental devido à sua toxicidade. O uso de fungos na degradação de corantes vem sendo estudado em diversos trabalhos científicos enquanto as vantagens econômicas e ambientais do uso de filtros lentos na produção de água bacteriologicamente segura há muito tempo já está descrita por diversos autores. Este trabalho teve por objetivo investigar a eficiência da remoção de corante artificial FD&C azul nº2 Indigotina, com uso do fungo de degradação branca Trametes versicolor em combinação com a filtração lenta. Para isso, foram instalados dois protótipos de filtros lentos denominados FL-A e FL-B em escala laboratorial, sendo que o filtro FL-A, foi inoculado com o fungo e o filtro FL-B, utilizado como controle, não foi inoculado com fungo. Três procedimentos foram empregados para o cultivo do fungo. Os resultados mostraram que a filtração lenta tem grande potencial para remoção eficiente de cor quando empregada em conjunto com o fungo Trametes versicolor. O melhor percentual de remoção do corante FD&C azul nº2 indigotina pelo fungo Trametes versicolor em combinação com a filtração lenta foi de 95% na metodologia com adição da biomassa de cultivo do fungo correspondente a duas placas de Petri. A média de descoramento da metodologia com adição de biomassa aumentada do fungo foi de 70%. Em todas as carreiras de filtração as perdas de cargas no FL-A, inoculado com fungo, foram superiores às do FL-B de controle. Este resultado indica que a biomassa gerada pelos fungos contribue para o aumento da perda de carga nos filtros lentos. Remoção de corantes filtros lentos fungo de decomposição branca Removal of dyes slow filters decomposition white fungus
30	Actions of lignocellulolytic enzymes on Abies grandis(grand fir) wood for application in biofuel production Cherdchim, Banyat 27 October 2010 (has links) No description available. 000 Allgemeines Wissenschaft Forest Sciences and Forest Ecology Abies grandis Armillaria mellea Heterobasidion annosum Heterobasidion parviporum Pleurotus ostreatus Trametes versicolor Coniophora puteana biodegradation cell wall modification urea formaldehyde ammonium sulphate mass loss area fraction stained cell wall cell wall area latewood earlywood oxidative enzyme MBTH laccase-mediator manganese peroxidase butylhydroxytoluol carbon chromatography fraction Coprinopsis cinerea decay fungi 1 4-dihydroxybenzene p-benzochinone 3 5-di-tertbut-4-hydroxy-toluene GC-MS analysis gel electrophoresis growth inhibition 4-hydroxy cinnamic acid laccase induction nitrogen phenolic compounds p-coumaric acid wood extraction wood extractives biofuels chemical pretreatment physico-chemical pretreatment biological pretreatment microwave irradiation liquid acid rate of production of glucose kinetic curve of production of glucose influence of wood extractive influence of phenolic compound Abies grandis Armillaria mellea Heterobasidion annosum Heterobasidion parviporum Pleurotus ostreatus Trametes versicolor Coniophora puteana biodegradation cell wall modification urea formaldehyde ammonium sulphate mass loss area fraction stained cell wall cell wall area latewood earlywood oxidative enzyme MBTH laccase-mediator manganese peroxidase butylhydroxytoluol carbon chromatography fraction Coprinopsis cinerea decay fungi 1 4-dihydroxybenzene p-benzochinone 3 5-di-tertbut-4-hydroxy-toluene GC-MS analysis gel electrophoresis growth inhibition 4-hydroxy cinnamic acid laccase induction nitrogen phenolic compounds p-coumaric acid wood extraction wood extractives biofuels chemical pretreatment physico-chemical pretreatment biological pretreatment microwave irradiation liquid acid rate of production of glucose kinetic curve of production of glucose influence of wood extractive influence of phenolic compound 48.46 Holz YQ 000: Forstbotanik

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