The 1,1-dichloroethene (1,1-DCE) cometabolic transformation abilities of indigenous and bioaugmented microorganisms were compared in microcosms constructed with groundwater and aquifer solids from the Moffett Field site, CA. Microbial community structure in the microcosms and possible community shifts due to 1,1-DCE transformation stress was evaluated by terminal restriction fragment length polymorphism method (T-RFLP). An existing biotransformation model was used to simulate the experimental data using parameter values determined by Kim et al. (2002) and Rungkamol (2001) with small adjustments to the parameter values. The laboratory microcosm studies showed that both indigenous and bioaugmented butane utilizers were capable of transforming 1,1-DCE when fed butane as a primary substrate. A butane-grown enriched culture was bioaugmented into the microcosms and exposed to several repeated additions of butane and/or 1,1-DCE, ranging from 7.1 to 76 ��mol and from 0.17 to 1.99 ��mol, respectively. The bioaugmented butane-utilizers showed a reduced lag period compared to the indigenous butane-utilizers. The greatest ability to transform 1,1-DCE was observed in bioaugmented microcosms, simultaneously exposed to butane and 1,1-DCE. Very little 1,1-DCE was transformed in the bioaugmented microcosms that were not fed butane, presumably due to lack of reductant supply and/or product toxicity of 1,1-DCE transformation. Microbial community analyses revealed similar results for replicate microcosms and differences in the community structure in microcosms subjected to different patterns of substrate addition and 1,1-DCE cometabolism. 1,1-DCE transformation resulted in temporal fluctuations in specific bacterial groups in the bioaugmented microcosms. It could be inferred that microorganisms, correlated with the T-RFL of 183 base pair (bp) were generally predominant in butane-fed bioaugmented microcosms simultaneously exposed to 1,1-DCE. Bioaugmented microcosms that were pre-exposed to 1,1-DCE for 29 days in the absence of growth substrate, followed by the addition of butane showed a significantly different microbial community from bioaugmented microcosms fed butane and 1,1-DCE simultaneously. Microorganisms with T-RFL of 179 or 277.8 bp dominated in these microcosms. These differences were possibly the result of extensive 1,1-DCE transformation product toxicity during the pre-exposure phase of the tests. A model developed by Kim et al. (2002) was used to mathematically describe the rate and extent of butane utilization and the cometabolic transformation of 1,1-DCE in the microcosm tests. Using the kinetic parameter values previously determined by Kim et al. (2002) and Rungkamol (2001), heuristic fits were obtained between the experimental data and model simulations. The model successfully predicted the trend of the butane utilization and 1,1-DCE transformation. The model outputs were statistically quantified for their fit to the experimental data by estimating Standard Error of Estimate (SEE). A reasonable fit between model predictions and experimental observations was achieved. A significant contribution of this study was developing the laboratory methods to evaluate the microbial abilities to cometabolize 1,1-DCE and determining the communities of microorganisms correlated with those biotransformation activities. Furthermore, the model comparison to experimental data indicated that there was a potential in using the existing model to predict and improve bioremediation strategies. The results showed the successful bioaugmentation of a butane-utilizing culture to improve transformation performance. / Graduation date: 2003

Access to abstract permanently restricted. / Access to thesis permanently restricted. / Department of Biology

Thesis (Ph. D.)--Georgia State University, 2006. / Title from title screen. George E. Pierce,committee chair; Eric S. Gilbert, Sidney A. Crow, committee members. Electronic text (135 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Aug. 20, 2007. Includes bibliographical references (p. 120-124).

Orientadores: Anita Jocelyne Marsaioli, Valeria Maia de Oliveira / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-08T05:19:46Z (GMT). No. of bitstreams: 1 Vasconcellos_SuzanPantarotode_D.pdf: 2236898 bytes, checksum: 015039f9f79ab3bebdcffa9003d44d0f (MD5) Previous issue date: 2006 / Resumo: Amostras de águas de formação de petróleo e óleos foram coletadas na Formação Pampo, situada na Bacia de Campos, através das quais, aplicando-se diferentes condições de cultivo, foram recuperadas 92 linhagens de bactérias aeróbias. Dentre os isolados, obtidos, 29 foram identificados por técnicas moleculares baseadas em DNAr 16S, observando-se a predominância de bactérias do gênero Bacillus.. De forma a constatar sobre a produção microbiana de metabólitos secundários com atividade inibitória ao desenvolvimento de outras espécies no reservatório de petróleo investigado, realizou-se análises de antibiogramas e Concentrações Inibitórias Mínimas (MIC), constatando Bacillus possuíam tal atividade. Sob condições anaeróbias foram obtidos consórcios microbianos, os quais foram caracterizados por técnicas independentes-de-cultivo, identificando-se bactérias do gênero Petrotoga como constituintes majoritários das comunidades presentes nos poços de petróleo amostrados. Duas espécies distintas de arquéias metanogênicas, Methanohalophilus sp. e Methanomethylovorans sp., também foram identificadas. Foram realizadas análises para a detecção da atividade biodegradadora da microbiota anaeróbia sobre biomarcadores do petróleo, onde foi observada forte tendência da comunidade microbiana investigada à biotransformação de compostos oxigenados (ácido octadecanóico; a e b-amirina). A biodegradação de biomarcadores do petróleo sob condições aeróbias revelou que a maioria das 29 bactérias avaliadas demonstrou tendência à biotransformação de ácidos carboxílicos de cadeia longa (ácido nonadecanóico). A linhagem de Micrococcus sp., entretanto, foi exceção a esta tendência, biotransformando preferencialmente hidrocarbonetos (fitano ediidrofenantreno), mesmo em presença de compostos oxigenados. A existência de interações simbióticas entre as comunidades microbianas aeróbias e anaeróbias nos processos de biodegradação de biomarcadores do petróleo, foi avaliada simulando atuação de ambas as microbiotas sobre uma mistura de hidrocarbonetos e compostos oxigenados. Os resultados obtidos sugeriram que a microbiota anaeróbia poderia sobreviver às custas dos metabólitos produzidos pela microbiota aeróbia durante a biodegradação do petróleo. A produção de exopolímeros microbianos com atividade bioemulsificante de hidrocarbonetos também foi determinada, verificando-se que microrganismos tidos com excelentes produtores de EPS não corresponderam às linhagens que apresentaram atividade biodegradadora de hidrocarbonetos do petróleo. Análises de triagens enzimáticas de alto desempenho (HTS) foram realizadas, e Dietzia sp. sobressaiu-se quanto às excelentes atividades de lipases, esterases e monooxigenases, enquanto Halomonas sp. apresentou o melhor desempenho quanto à atividade de epóxido hidrolase / Abstract: Samples of petroleum formation water and oils were collected from Pampo Formation (Campos Basin). Applying different conditions of microbial cultivation it was recuperated 92 bacterial strains from among 29 were identified by molecular techniques based in rDNA 16S. The predominance of Bacillus genus was observed in this recuperated bacterial community. The production of microbial secondary metabolites with antibiotic activity was investigated through analysis of antibiograms and Microbial Inibitory Concentrations (MIC) assays. Strains of Bacillus produced metabolites with microbial growth inhibition that can actuate in the petroleum reservoir in the selection of microbial species. Under anaerobic conditions microbial consortia were characterized by independent of cultivation techniques, identifying bacteria of Petrotoga genus as main constituent from the sampled reservoir. Two distinct species of methanogenic archaea, Methanohalophilus sp and Methanomethylovorans sp, were identified too. Analysis for the detection of the biodegrader activities of anaerobic microbiota under petroleum biomarkers were realized. Strong tendency of this microbial community to oxygenated compounds biotransformation was observed. The biodegradation of petroleum biomarkers under aerobic conditions was investigated as a form to determinate the microbial preferences for the petroleum compounds, in mixture or isolate, evaluating the formed products. The results presented the preference for the biotransformation of long chain carboxylic acids before the metabolism of hydrocarbons. Although, the strain of Micrococcus sp. preferred the biotransformation of hydrocarbons (phytane and dihydrophenanthrene), not biodegrading the fatty acid in strong levels. To investigate about the existence of symbiotic interactions between aerobic and anaerobic microbial communities in petroleum biodegradation processes, the actuation of the both microbiota under a mixture of hydrocarbons and oxygenated compounds was simulated. The obtained results suggest that the anaerobic microbiota can survive from the aerobic metabolites produced by the aerobic community. The production of microbial exopolymers with bioemulsifier activity of hydrocarbons was determined too. It was verified that strains presented as excellent producers of bioemulsifiers are not efficient petroleum biodegraders. Analysis of High Throughput Screening (HTS) were realized and Dietzia sp. presented strong activities of lipases, esterases and monooxygenases, while Halomonas sp. was the best result how the epoxide hydrolase activity / Doutorado / Quimica Organica / Doutor em Ciências

D.Phil. (Biochemistry) / This thesis concerns a study of the effect of isonitrosoacetophenone on plant metabolism. Three different systems were investigated; cultured tobacco and sorghum cells as well as Arabidopsis thaliana plants, and a metabolomic approach was followed. Unlike most scientific studies, metabolomics is a discipline which is not driven by a specific hypothesis, but rather by the obtained data to add scientific insights to the topic under investigation. As such, the current study lacks a definite overarching hypothesis, but specific objectives were outlined and answered in each experimental chapter. This thesis is therefore presented as a compilation of nine chapters in which experimental/research work is described in Chapter 3- 8. It is important to note that each chapter is presented in accordance with the guidelines for the respective journal in which the corresponding manuscript was published or submitted to.

In a program aimed at the identification of compounds responsible for the immunosuppressive and antifertility activities of the perennial twining vine, Tripterygium wilfordii. 5 new and 13 known compounds were isolated from the TRP-4a tissue culture cell line developed from Tripterygium wilfordii. The structures of the new compounds were determined by a combination of spectral analysis, chemical correlation and single crystal X-ray diffraction analysis. 22β-Hydroxy-3-oxoolean-12-en-29-oic acid (137), 22α-hydroxy-3-oxoolean- 12- en-29-oic acid (138) and 3β, 22β-dihydroxyolean-12-en-29-oic acid (139) are new triterpenes possessing an oleanene-type skeleton and were chemically correlated with 3β, 22α-dihydroxyolean-12-en-29-oic acid (51), the structure of which was confirmed by single crystal X-ray diffraction analysis. Oleanolic acid (127), β-sitosterol (128) and polpunonic acid (55), were isolated previously from the TRP-4a cell line in earlier studies in this laboratory. α-Amyrin (145), β-amyrin (146), 3β, 29-dihydroxyolean-12-ene (151) and 3β, llα-dihydroxyolean-12-ene (152) are known triterpenes possessing an oleanene-type skeleton and are isolated for the first time from the TRP-4a cell line. Tingenone (148) and 22β-hydroxytingenone (150) are quinone methide triterpenes, also isolated for the first time from the TRP-4a cell line. Similarly, the novel diterpene, 12-methoxyabieta-8, 11, 13- trien-3α-ol (147) and the novel triterpene, methyl-22β-hydroxy-3, 21-dioxo-D:A-friedo-29-noroleanan-24-oate (149), a member of the friedelane family, are isolated for the first time. A biosynthetic pathway, based on the isolation of 149 and its structural similarity to polpunonic acid (55) and 22β-hydroxytingen6ne (150), is postulated for the quinone methides. The cytotoxic diterpenes, tripdiolide (1) and triptolide (2) and the hydroxy acid, 160, isolated as the methyl ester, 124, have been previously reported from this laboratory. Tripdiolide (1) and triptolide (2) have been shown to possess strong antifertility and immunosuppressive activities. In another aspect of our program, biotransformation studies of the synthetic precursors, 19 (4➙3)abeo-abieta-2, 8, 11, 13-tetraen-19-ol (171) and 19-hydroxy-18(4➙3)abeo-abieta-3, 8, 11, 13-tetraen-18-oic acid lactone (91), and the radioactive congeners, 182 and 209, were carried out using the TRP-4a cell line. It was hoped that the data obtained might shed some light on the "late stage" biosynthetic pathway of the diterpene triepoxides, tripdiolide (1) and triptolide (2). Synthesis of 171 was achieved in 5 steps from dehydroabietic acid (80). The radioactive congener, 182, was synthesised using ¹⁴C-paraformaldehyde with 0.4% incorporation of the radiolabel. Biotransformation of 171 using the TRP-4a cell line yielded 19(4➙3)abeo-abieta-2, 8, 11, 13-tetraen-19-al (185) and 19(4➙3)abeo-abieta-2, 8, 11, 13-tetraen-19-oic acid (186) for spectral identification. Biotransformation of 182 yielded the aldehyde, 183 (33.2%) and the acid, 184 (51.9%), the radioactive congeners of 185 and 186 respectively. Synthesis of 91 was achieved in 4 steps from dehydroabietic acid (80). The radioactive congener, 209, was synthesised using ¹⁴C-methyl iodide via ¹⁴C-dimethylsulphonium methylide, with 0.6% incorporation of the radiolabel. Biotransformation of 91 using TRP-4a tissue cultures yielded 19-hydroxy-7-oxo-18(4➙3)abeo-abieta-3, 8, 11, 13-tetraen-18-oic acid lactone (214), 2β, 19-dihydroxy-7-oxo-18(4➙3)abeo-abieta-3, 8, 11, 13-tetraen-18-oic acid lactone (215), 7β, 19-dihydroxy-18(4➙3)abeo-abieta-3, 8, 11, 13-tetraen-18-oic acid lactone (216) and 2β 19-dihydroxy-18(4➙3)abeo-abieta-3, 8, 11, 13-tetraen-18-oic acid lactone (96), for spectral identification. Biotransformation of 209 yielded the ketone, 210 (56.7%), the hydroxy ketone, 211 (5.9%), the benzylic alcohol, 212 (9.6%) and the C2 alcohol, 213 (6.8%), the radioactive congeners of 214,215,216 and 96 respectively. A biosynthetic pathway to the diterpene triepoxides is postulated based on the oxygenated biotransformation products. [formulas omitted] / Science, Faculty of / Chemistry, Department of / Graduate

Dominant genera of bacteria were isolated from three river waters during anthracene and pentachlorophenol biotransformation studies. The genera Pseudomonas, Acinetobacter, Micrococcus, Chromobacterium, Alcaligenes, Azomonos, Bacillus, and Flavobacterium were capable of biotransforming one or both of these compounds. These isolates were subjected to further biotransformation tests, including river water and a basal salt medium with and without additional glucose. The results of these experiments were evaluated statistically. It was concluded that only a limited number of the bacteria identified were able to transform these chemicals in river water. The addition of glucose to the growth medium significantly affected the biotransformation of these chemicals. It was also determined that the size of the initial bacterial population is not a factor in determining whether biotransformation of anthracene or pentachlorophenol can occur.

No description available.

Naphthenic acids (NAs) are carboxylic acids found in crude oil and petroleum products. The objectives of the research presented here were to: a) assess the occurrence and fate of NAs in crude oil and refinery wastewater streams; b) evaluate the biotransformation potential and inhibitory effects of NAs under nitrifying, denitrifying and methanogenic/fermentative conditions; c) investigate the factors affecting NA biotransformation under aerobic conditions and the microbes involved; and d) assess the toxicity of individual model NAs using quantitative structure-activity relationships (QSAR) and examine the effect of structure on NA biotransformation potential. NAs are ubiquitous in refinery wastewater streams and the desalter brine was found to be the main source of NAs in refinery wastewater. A commercial NA mixture was not biodegraded under nitrate-reducing or methanogenic/fermentative conditions. NAs were degraded under aerobic conditions by an NA-enriched culture; however, a residual fraction was not degraded under all conditions studied. The results indicated that NAs are not inherently recalcitrant and the residual fraction was due to the individual NA concentrations being below the minimum substrate concentrations at which they are no longer degraded. A fraction of the NA mixture was completely mineralized to carbon dioxide, with the remaining portion biotransformed to more oxidized intermediates. Overall, the results indicated that NAs were degraded under aerobic conditions; however, biological treatment of NA-bearing wastewater will not completely remove NA concentrations and thus, biological treatment must be combined with physical/chemical treatment to achieve complete NA removal.

Phytosterols are naturally occurring compounds which regulate membrane fluidity and serve as hormone precursors in plants. They also have the potential to cause endocrine disturbances in aquatic animals at concentrations as low as 10 µg/L. Wastewaters from several industries which process plant matter can contain phytosterols at concentrations in excess of the above-stated level. Despite their endocrine disruption potential, very little is known about phytosterol physical properties and their biotransformation potential in biological treatment systems. Aerated stabilization basins (ASBs) are common biological treatment systems in North American pulp and paper mills. ASBs are large open lagoons which use tapered surface aeration to remove COD and prevent sulfate reduction in the water column. Phytosterols are released from wood during the pulping process and a small fraction enters the wastewater stream during washing of the pulp. Therefore, phytosterols may be exposed to aerobic or anaerobic environments depending on their solubility and solid-liquid partitioning behavior. The overall objective of this research was to systematically and quantitatively assess the biotransformation potential of phytosterols in biological treatment systems and to examine conditions leading to reduction of these compounds in wastewater effluent streams. The results of this research showed that phytosterols are sparingly soluble with aqueous solubility below 1 µg/L when present as a mixture. Phytosterols have a strong affinity to adsorb to solids and dissolved organic matter. The affinity for aerobic biomass was greater than for wastewater solids. The stigmasterol desorption rate and extent from wastewater solids increased with an increase in pH from 5 or 7 to 9. Phytosterols were biotransformed under aerobic conditions but not under sulfate-reducing or methanogenic conditions by stock cultures developed in this study. Biotransformation under nitrate-reducing conditions could not be confirmed conclusively. The continuous-flow system was successful in removing 72 to 96% of phytosterols. Biotransformation accounted for 23, 14 and 41 % of campesterol, stigmasterol and β-sitosterol removal, respectively. Phytosterols accumulated in the reactor sediment and accounted for 97 % of the total phytosterols remaining in the system. Phytosterols can be removed from wastewater streams during biological treatment by a combination of biotransformation and solids partitioning and control of system pH, DO and available carbon and energy sources can increase the degree of phytosterols removal. The results of this research can be used to engineer effective biological treatment systems for the removal of phytosterols from pulp mill wastewaters and other phytosterol-bearing wastewater streams.