A elevada concentração de cloro das bifenilas policloradas provoca alta toxicidade do composto, o qual dificulta sua biodegradação. A contaminação de PCB no Brasil foi confirmada em estudo realizado na Bahia de Santos-São Vicente (São Paulo), o qual revelou a necessidade de um plano de ação para o controle e remoção de PCB no Brasil. Pretendeu-se assim, na realização da presente pesquisa, verificar quatro hipóteses: (1) A técnica de Microextração em fase sólida é uma metodologia eficaz para avaliação de bifenilas policloradas de amostras de reatores; (2) A condição fermentativa-metanogênica abriga comunidade resistente ao PCB, e removê-lo; (3) A condição desnitrificante abriga comunidade resistente ao PCB, e removê-lo e (4) A remoção de PCB, bem como, a composição microbiana é distinta em cada condição metabólica. Para tanto, reatores em batelada foram montados separadamente com biomassa anaeróbia proveniente de reator UASB usado no tratamento de água residuária de avicultura e biomassa de sistemas de lodos ativados de tratamento de esgoto sanitário. Os reatores operados em condição mesófila foram alimentados com meio sintético, co-substratos, sendo etanol (457 mg.L-1) e formiato de sódio (680 mg.L-1) para os reatores anaeróbios, e somente etanol (598 mg.L-1) para os reatores anóxicos, além de PCB padrão Sigma (congêneres PCBs 10, 28, 52, 153, 138 e 180) em diferentes concentrações, dependendo do objetivo do ensaio. A aplicação do método de extração por SPME com análise em cromatógrafo gasoso com detector por captura de elétrons foi adequada para a determinação dos seis congêneres de PCB. Obteve-se ampla faixa de linearidade, seletividade frente aos vários interferentes, além da robustez do método, utilidade e confiabilidade na identificação e quantificação específica dos seis congêneres de PCB. A Hipótese 1 foi aceita; ou seja, por meio da aplicação da metodologia SPME foi possível quantificar os PCB nos reatores em batelada. Apesar de ter sido comprovada a inibição metanogênica na presença de PCB, com IC50 de 0,03 mg.L<sup-1 (concentração na qual 50&#37; da atividade metanogênica é inibida), a partir da análise dos reatores metanogênicos no Ensaio de Remoção, foi confirmada a remoção de 0,92 mg.L-1, 0,19 mg.L-1, 0,18 mg.L-1, 0,07 mg.L-1, 0,55 mg.L-1 e 0,47 mg.L-1 para os PCBs 10, 28, 52, 153, 138 e 180, respectivamente, para 1,5 mg.L-1 inicial. Thermotogaceae, Sedimentibacter, Anaerolinaceae e Pseudomonas, foram identificadas nos reatores anaeróbios por meio da plataforma Illumina. Representantes de Thermotogaceae e Sedimentibacter foram identificados em sistemas com elevada taxa de remoção de PCB, e representantes do filo Chloroflexi (grupo no qual representantes da Anaerolineae estão inseridos) foram os primeiros microrganismos desalogenadores de PCB identificados. Assim a Hipótese 2 foi aceita; ou seja, por meio de ensaios em batelada foi comprovada a toxicidade do PCB sobre a comunidade anaeróbia, a alteração da composição microbiana influenciada pela presença de PCB e a remoção nesta condição. Verificou-se ainda que na presença de PCB ocorreu a desnitrificação e comparando-se diferentes relações C/N-NO3-, foi estipulado a relação 6,95 como ideal na presença de PCB. Mesmo sendo confirmada a inibição da comunidade anóxica na presença de PCB com IC50 de 1,0 mg.L-1, verificou-se remoção de 1,02 mg.L-1, 0,85 mg.L-1, 1,31 mg.L-1, 1,02 mg.L-1, 0,03 mg.L-1, e 0,09 mg.L-1, para os PCBs 10, 28, 52, 153, 138 e 180, respectivamente, para 1,5 mg.L-1, inicial. Bactérias semelhantes a Aeromonadaceae, Lutispora, Sedimentibacter e Thermotogaceae foram identificadas nos reatores desnitrificantes. Representantes de Aeromonadaceae e Lutispora estão relacionados com o metabolismo desnitrificante e representantes de Thermotogaceae e Sedimentibacter foram identificados em sistemas com elevada taxa de remoção de PCB. A Hipótese 3 foi também aceita; ou seja, por meio de ensaios em batelada foi calculada a relação C/N-NO3- ideal na presença de PCB e foi comprovada a toxicidade do PCB sobre a comunidade anóxica, a alteração da composição microbiana influenciada pela presença de PCB e a remoção nesta condição. A maior remoção de PCB foi verificada para a condição anaeróbia (entre 45&#37; a 100&#37;), quando comparada com a condição anóxica (entre 10&#37; a 95&#37;). Bactérias semelhantes a Sedimentibacter e pertencentes a família Thermotogaceae foram identificadas nas duas condições nutricionais. Entretanto, mesmo verificando-se elevada abundancia relativa desses grupos nos reatores, evidenciou-se distinção entre as biomassas em cada condição. Assim, a Hipótese 4 foi aceita; ou seja, por meio de ensaios em batelada foi comprovada maior eficiência de remoção sob condição anaeróbia e distinta composição microbiana em cada condição. / The high chlorine concentration in polychlorinated biphenyls improves its toxicity, complicating their biodegradation. A study conducted in Santos-São Vicente Bay (São Paulo) confirmed the PCB contamination in Brazil and reveled the need of an action plan to control e remove the PCB in Brazil. In this sense the aim of this study was to evaluate four hypotheses: (1) The Solid Phase Micro Extraction is an efficient methodology to evaluate biphenyl polychlorinated in reactors; (2) The fermentative-methanogenic microorganisms are resistant to PCB and capable to consume it; (3) The denitrifying microorganisms are resilient to the PCB and capable to remove it; (4) The PCB removal, as well the microbial composition is distinct in each condition. Therefore, batch reactors were operated separately inoculated with anaerobic biomass from UASB reactor treating poultry wastewater and biomass from activated sludge treating sewage wastewater. The reactors were feed with synthetic medium, co-substrates, as ethanol (457 mg.L-1) and sodium formate (680 mg.L-1) for the anaerobic reactors, and ethanol (598 mg.L-1) for the anoxic reactors and different concentrations of six congeners of PCB (PCBs 10, 28, 52, 153, 138 and 180) depending on the aim of the assay. The applicability of SPME technique in gas chromatography with electrons capture detection was attested in the analysis of six PCB congeners. Higher linearity, selectivity, accuracy, reproducibility and robustness was obtained in the PCB quantification analyses. The Hypothesis 1 was accepted; since the PCB congeners in the reactors were quantified by the SPME methodology. Although the PCB causes methanogenic inhibition, with IC50 of 0.03 mg.L-1 (concentration in which 50&#37; of the methanogenic metabolism is inhibited), by the Removal Assay was confirmed the anaerobic removal of 0.92 mg.L-1, 0.19 mg.L-1, 0.18 mg.L-1, 0.07 mg.L-1, 0.55 mg.L-1 and 0.47 mg.L-1 to PCB 10, 28, 52, 153, 138 and 180, respectively, for 1.5 mg.L-1 initial. By means of platform Illumina Thermotogaceae, Sedimentibacter, Anaerolinaceae and Pseudomonas, were identified in the anaerobic reactors. The Thermotogaceaeand Sedimentibacter were related to systems with high PCB removal and the Chloroflexi members (Anaerolineae phylum) were the first PCB-dechlorination microorganisms identified. Therefore, the Hypothesis 2 was accepted since the PCB leads to anaerobic inhibition and in the reactors were verified the PCB removal and changes in the microbial composition. Even with PCB, the denitrification metabolism occurs and evaluating different C/N-NO3- relations, the 6.95 was stipulated the ideal in the presence of PCB. Even though the PCB causes inhibition in the denitrification bacteria, with IC50 of 1.0 mg.L-1, by the Removal Assay in the denitrifying reactors, was confirmed the anoxic removal 1.02 mg.L-1, 0.85 mg.L-1, 1.31 mg.L-1, 1.02 mg.L-1, 0.03 mg.L-1 and 0.09 mg.L-1 to PCB 10, 28, 52, 153, 138 and 180, respectively, for 1.5 mg.L-1 initial. Aeromonadaceae, Lutispora, Sedimentibacter and Thermotogaceae were identified in the denitrifying reactors. Members of Aeromonadaceae e Lutispora were related to the denitrification metabolism and Thermotogaceae e Sedimentibacter were identified in systems with high PCB removal rate. The Hypothesis 3 was accepted since the PCB leads to anoxic inhibition and in the reactors were verified the PCB removal and changes in the microbial composition. The anaerobic reactors presented the higher PCB removal percentage (between 45&#37; and 100&#37;) when compared to the anoxic reactors (between 10&#37; and 95&#37;). Member of Sedimentibacter and Thermotogaceae were identifyied in both conditions. However, even with high relative abundance of these two groups in the reactors, it was shown distinct composition in each biomass. Thus, the Hypothesis 4 was accepted since the PCB removal was more efficient in the anaerobic condition and were verified different changes in the microbial composition in each condition.

No description available.

Stimulating in situ microbial communities in oil reservoirs to produce natural gas is a potentially viable strategy for recovering additional fossil fuel resources following traditional recovery operations. Little is known about what geochemical parameters drive microbial population dynamics in biodegraded, methanogenic oil reservoirs. We investigated if microbial community structure was significantly impacted by the extent of crude oil biodegradation, extent of biogenic methane production, and formation water chemistry. Twenty-two oil production wells from north central Louisiana, USA, were sampled for analysis of microbial community structure and fluid geochemistry. Archaea were the dominant microbial community in the majority of the wells sampled. Methanogens, including hydrogenotrophic and methylotrophic organisms, were numerically dominant in every well, accounting for, on average, over 98% of the total Archaea present. The dominant Bacteria groups were Pseudomonas, Acinetobacter, Enterobacteriaceae, and Clostridiales, which have also been identified in other microbially-altered oil reservoirs. Comparing microbial community structure to fluid (gas, water, and oil) geochemistry revealed that the relative extent of biodegradation, salinity, and spatial location were the major drivers of microbial diversity. Archaeal relative abundance was independent of the extent of methanogenesis, but closely correlated to the extent of crude oil biodegradation; therefore, microbial community structure is likely not a good sole predictor of methanogenic activity, but may predict the extent of crude oil biodegradation. However, when the shallow, highly biodegraded, low salinity wells were excluded from the statistical analysis, no environmental parameters could explain the differences in microbial community structure. This suggests that the microbial community structure of the 5 shallow, up-dip wells was different than the 17 deeper, down-dip wells. Also, the 17 down-dip wells had statistically similar microbial communities despite significant changes in environmental parameters between oil fields. Together, this implies that no single microbial population is a reliable indicator of a reservoir's ability to degrade crude oil to methane, and that geochemistry may be a more important indicator for selecting a reservoir suitable for microbial enhancement of natural gas generation.

In Brazil, with the continued expansion of agriculture for supplying demands from international markets, progressive increases in emissions of green house gases are expected. The purpose of the project was hypothesized with three major approaches, 1) Strategies to mitigate methane emission in small ruminant production systems; 2) Identify tropical plants and individual bioactive compound against methanogenic propertie and 3) In vivo evaluation of the nutrients metabolism of Santa Ines sheep fed with tropical plants. For this, we have performed three experiments. The first study (Expt. 1) was designed to determine the in vitro effects of three tropical tannin rich plants such as Leucaena leucocephala (LL), Mimosa caesalpineafolia (MC), Schinus molle (SM) and one non-tannin rich plant Medicavo sativa (MS) for their anti-methanogenic properties when used with and without polyethylene glycol (PEG). All plants had significantly (P<0.05) influenced the degraded organic matter (TDOM) and degraded neutral detergent fiber (DNDF), especially LL, which had most influence on these parameters compared to other tannin containing plants. LL had positive response on antimethanogenic effects; its nutrient degradability was higher than that of other tannin containing plants. The second study (Expt. 2) was set to evaluate the effect of different organic extracts from the whole plant methanolic extract (MHE) of LL on in vitro gas production and to characterize the chemical constituents by using gas chromatography coupled with mass spectroscopy (GC-MS). Major abundant compounds present at the relative percentages of MHE were found to be stigmasterol trimethyl ester (TMS), neophytadiene, palmitic acid TMS, ?-Linolenic acid TMS and 2, 3, 5, 6-Tetra-M-Anisylbenzene. The effects of additions of different extracts in terms of nutrient degradability (TDOM and DNDF) were increased by all extracts. This study explained that the hexane extract from whole plant MHE was effective against methanogenic activity. The objective of the third study (Expt. 3) was to study the effect of LL plant leaves on rumen fermentation, apparent nutrient digestibility, nitrogen balance and methane production in Santa Ines sheep. The animals were divided in three groups in which they were fed with (i) 88% Tifton 85-hay (Cynodon dactylon) and 12% soyabean meal (Control group, n=4); (ii) 28% Tifton 85-hay (Cynodon dactylon) and 72% LL plus 20 ml solution containing 10g/day/animal of PEG (With PEG group - WPEG, n=6); (iii) 28% Tifton 85-hay (Cynodon dactylon) and 72% LL plus 20 ml of distilled water (Without PEG group- WOPEG, n=6). Nutrient intake (dry matter, organic matter, acid detergent fiber, lignin and crude protein) were higher in WPEG and WOPEG compared to the control group, except neutral detergent fiber intake. Apparent digestibilities and nitrogen metabolism had non-significant effects between the treatments. However, CH4 emissions were significantly lower in WPEG and WOPEG than the control. Furthermore, expressions of microbial populations of methanogens in WPEG had lower tendency than that of WOPEG and control. The most salient findings of this study were that, using plant rich in tannin in diets of small ruminants, we can get more benefits in terms of replacing the source of protein in the diet (food safety) and reduced production of enteric CH4 (animal production) / No Brasil, com expansão da agricultura para suprir as exigências dos mercados internacionais, são esperados aumentos progressivos nas emissões de gases do efeito estufa. O objetivo do projeto foi hipotetisado com três abordagens principais, 1) estratégias para mitigar emissões de metano em sistemas de produção de pequenos ruminantes; 2) identificar plantas tropicais com compostos bioativos com propriedades anti metanogénicas e 3) avaliação in vivo do metabolismo de nutrientes em ovelhas Santa Inês alimentadas com planta taninífera. Para isso, foram efetuados três experimentos. O primeiro estudo (Expt 1) foi concebido para estudar os efeitos in vitro de plantas tropicais ricas em tanino como Leucaena leucocephala (LL), Mimosa caesalpineafolia (MC) e Schinus molle (SM) e uma planta não taninífera, Medicavo sativa (MS) quanto às propriedades anti-metanogénicas quando usadas com e sem polietileno glicol (PEG). Todas as plantas significativamente (P < 0.05) influenciaram na matéria orgânica degradada (MOD) e na fibra em detergente neutro degradada (FDND), especialmente a LL, que teve maior influência sobre estes parâmetros, em comparação com as outras plantas que contém tanino LL teve resposta positiva sobre os efeitos de antimethanogênicos e a degradabilidade dos nutrientes foi maior do que a das outras plantas que contém tanino. O segundo estudo (Expt 2) foi definido para avaliar o efeito de diferentes extratos orgânicos a partir do extrato metanólico da planta (EMP) de LL na produção de gás in vitro e caracterizar os constituintes químicos usando cromatografia gasosa acoplada com espectroscopia de massa (GC-MS). Os compostos mais abundantemente encontrados, em termos de percentagens relativas do EMP, foram o éster de trimetil estigmasterol, neofitadina, ácido palmítico, ácido ?-linolênico e 2, 3, 5, 6-Tetra-M-anizil -benzeno. Os efeitos de adições dos diferentes extratos orgânicos, em termos de degradabilidade de nutriente (MOD e NDFD) foram aumentados para todos os extratos. Este estudo explicou que o extrato de hexano a partir do EMP foi eficaz na atividade anti metanogênicas em modificar a degradação ruminal de nutrientes. O objetivo do terceiro estudo (Expt 3) foi estudar o efeito das folhas da planta LL na fermentação ruminal, digestibilidade aparente de nutrientes, balanço de nitrogênio e produção de metano em ovinos Santa Inês. Os animais foram divididos em três grupos em que eles foram alimentados com (i) 88% feno de Tifton-85 (Cynodon dactylon) e 12% de farelo de soja (Grupo controle, n = 4); (ii) 28% feno de Tifton-85 (Cynodon dactylon) e 72% LL mais 20 ml solução contendo 10g/dia/animal de PEG (grupo com PEG - CPEG, n = 6); (iii) 28% feno de Tifton-85 (Cynodon dactylon) e 72% LL mais 20 ml de água destilada (sem PEG-grupo-SPEG, n = 6). A ingestão de nutrientes (matéria seca, matéria orgânica, fibra em detergente ácido, lignina e proteína bruta) foram maiores no grupos CPEG e SPEG em relação ao grupo controle, exceto a ingestão de fibra em detergente neutro. As digestibilidades aparentes e o metabolismo do nitrogênio não apresentaram efeitos significativos entre os tratamentos. No entanto, as emissões de CH4 foram significativamente inferiores nos grupos CPEG e SPEG em comparação com o grupo controle. Além disso, as expressões de populações microbianas de metanogênicas no grupo CPEG apresentaram tendência menor do que nos grupos SPEG e controle. As conclusões mais salientes do presente estudo foram que, usando planta rica em tanino em dietas de pequenos ruminantes, poderemos ter mais benefícios em termos de substituição da fonte de proteína da dieta (segurança alimentar) e redução da produção de CH4 entérico

Bifenilas policloradas (PCBs) são compostos de difícil degradação presentes na composição de ascarel, muito utilizado como fluidos dielétricos e isolantes. Neste contexto, a presente pesquisa teve como objetivo avaliar a diversidade de microrganismos em biofilmes de reatores anaeróbios na presença de PCB empregando Métodos de Microbiologia de Anaeróbios Estritos e de Biologia Molecular. Em reator anaeróbio horizontal de leito fixo (RAHLF), alimentado com etanol, formiato, Triton X-100 (0,1%) e ascarel (1 mL/L), operado com tempo de detenção hidráulica (TDH) de 24 horas, foi retirado a comunidade microbiana do biofilme da espuma de poliuretano. Os grupos microbianos encontrados por meio da clonagem e sequenciamento do gene RNAr 16S para o domínio Bacteria foram relacionados aos filos Thermogae, Proteobacteria (Brachymonas petroleovorans, 100% de similaridade e Methylobacillus, 98% de similaridade), Firmicutes (Clostridium, 97% de similaridade, Syntrophomonas, 100% de similaridade e Sporomusa com 100% de similaridade), Synegistetes (Synergistes, 98% de similaridade), Spirochaetes (Leptonema illini, 98% de similaridade), Aminanaerobia, Deferribacteres, Chlorobi, Chloroflexi e Armatimonadetes. Além disso, como nesse biofilme foram identificadas bactérias redutoras de ferro, procedeu-se a sua quantificação por meio da técnica de tubos múltiplos (NMP, Número Mais Provável) obtendo 5,26 x \'10 POT.12\' NMP/g STV de bactérias redutoras de ferro. Ensaio em batelada foi realizado separadamente sob duas condições: (1) metanogênica e (2) ferro redutora. Em ambas as condições foram adicionadas aroclor 1260 (PCB). Os reatores, sob condição metanogênica, foram alimentados com meio de cultivo Angelidaki e substratos orgânicos (formiato e etanol), além de aroclor 1260 (0,2 \'mü\'g/L). Para simular a condição redutora de ferro foi acrescido ao meio de cultura Angelidaki, EDTA férrico (1,86 g/L). A produção de metano, na presença de aroclor 1260 foi de 3,8 x \'10 POT.-4\' mmol \'CH IND.4\'/g STV. A presença de bactérias ferro redutoras foi confirmada indiretamente pela taxa média de redução férrica (90%) nos reatores em batelada, após 60 dias de operação. Por meio de PCR/DGGE, elaborou-se um dendograma das amostras deste ensaio em batelada (metanogênico e redutor de ferro) comparativamente com as do reator RAHLF (biofilme presente na parede do reator e no material suporte). Os reatores em batelada apresentaram similaridade entre si de 79% e 92% para os domínios Bacteria e Archaea, respectivamente. As amostras do reator RAHLF foram 80% (Bacteria) e 96% (Archaea) similares. A existência de bactérias degradadoras de PCB, bem como, bactérias redutoras de ferro no biofilme anaeróbio contribuiu com informações sobre o consórcio microbiano e sua diversidade. / Polychlorinated biphenyls (PCBs) are compounds of difficult degradation, a component of askarel, which were used widely as coolants and lubricants. Hence, this study evaluated the diversity of microorganisms in the presence of PCBs in anaerobic reactors. For such, methods as Strict Anaerobic Microbiology and Molecular Biology were employed. The microbial community of the biofilm, developed in a fixed horizontal bed anaerobic reactor (RAHLF), was studied using the technique of cloning and sequencing of RNAr 16S gene for the Bacteria domain. The reactor had immobilized cells in polyurethane foam with ethanol and formate as a carbon source, Triton X-100 (0.1%) and polychlorinated biphenyls (1 mL/L), and operated with 24 hours HRT. The microbial groups found in this biofilm were related to phyla Thermogae, Proteobacteria (Brachymonas petroleovorans, 100% similarity and Methylobacillus, 98% similarity), Firmicutes (Clostridium, 97% similarity Syntrophomonas, and 100% similarity with Sporomusa 100% similarity), Synegistetes (Synergistes, 98% similarity), Spirochaetes (Leptonema Illini, 98% similarity), Aminanaerobia, Deferribacteres, Chlorobi, Chloroflexi and Armatimonadetes. Furthermore, as bacteria that reduce iron were found, we proceeded the quantification by the multiple tube method (MPN) for this group, obtaining 5.26 x \'10 POT.12\' MPN/g STV of iron-reducing bacteria. The batch reactors evaluated the growth of microorganisms in two condictions: (1) methanogenic e (2) iron reduction, both had the presence of PCBs (Aroclor 1260). The reactor, under methanogenic condition, was fed with synthetic substrate Angelidaki, ethanol and formate, used as carbon source, and aroclor 1260 (0.2 \'mü\'g /L). To simulate the condition of iron reducing, the same synthetic substrate was supplemented with ferric EDTA (1.86 g/L). The production of methane in the presence of aroclor 1260, was 3.8 x \'10 POT.-4\' mmol \'CH IND.4\'/g STV. The presence of iron reducing bacteria, after 60 days, was confirmed indirectly by the average rate of iron ferric reduction (90%). Filogenetics analysis (PCR/DGGE) compared the samples of this batch reactor - methanogenic and reduction of iron ferric -, with the samples of RAHLF - the biofilm in the reactor wall and the support material. The two condictions in batch reactors showed similarity of 79% and 92% respectively for the Bacteria and Archaea domain. Therefore, both samples of RAHLF showed 80% (Bacteria) and 96% (Archaea) of similarity. In other words, more similarity were presented due configuration of the reactor as well as the type of PCB added. As a result, the existence of PCBs degrading bacteria and iron-reducing bacteria in anaerobic biofilm, provided informations about the microbial consortium and its diversity in the presence of PCB.

Made available in DSpace on 2017-05-12T14:47:12Z (GMT). No. of bitstreams: 1 Izabela Regina Costa _Araujo.pdf: 2798947 bytes, checksum: 10a0bad3f765462b54bb964dd971203c (MD5) Previous issue date: 2015-02-19 / Researches have shown that among several ways of treating cassava starch wastewater, anaerobic process has been considered a simple and economical option that combines the high content of organic matter conversion to biogas production. On the other hand, biogas is a potential energy resource that can be used to supply part of the energy demands from industrial plants. Thus, this trial aimed at evaluating an anaerobic reactor with fixed bed up-flow, regarding the removal of organic load in wastewater from cassava starch extraction as well as biogas production. So, volumetric organic loads (VOC) of 2.5; 5.0; 8.0 and 10.0 g.L-1.d-1 were tested in a 2.82 L volume reactor. A support medium of polypropylene rings filled with polyurethane foam was used. The monitored parameters regarding the reactor effluent were: pH, volatile acidity (VA), total alkalinity (TA), VA/TA ratio, total solid concentrations (TS), volatile solids (VS), total suspended solids (TSS), volatile suspended solids (VSS), total chemical oxygen demand (TCOD), soluble chemical oxygen demand (SCOD) and organic acids. The reactor performance was tested in relation to removals of solids, organic load, as well as biogas and methane production. As the most important results, it was observed that the reactor remained constant concerning pH, total removal of VSS and removals of TCOD and SCOD. While, there were also lactic, butyric, propionic and acetic acids in the studied effluent, although acetic acid was recorded in higher concentrations. Biogas production average was 3.8 L.d-1, the average of specific biogas production was 0.156 L.gCODconsumed-1, but VOC answer was 10.0 g.L-1.d-1, being the greatest results for both of them. Methane percentage in biogas ranged from 66 to 84% and the specific methane production ranged from 0.01 to 0.36 Lg-1. The highest values were obtained in VOC - 2.5 and 10.0 g.L-1d-1, respectively. The removal of medium TS, VS, TSS and VSS were 72, 80, 63 and 92%, respectively. The average removals of TCOD and SCOD were 98.7 and 97.9 respectively, therefore, the highest removal rates were obtained for 10.0 and 2.5 VOC g.L-1.d-1. Thus, it can be concluded from this trial that it is possible to produce biogas with a methane percentage higher than 80% (maximum) and remove the organic loading rate by more than 90% (maximum) according to tested configuration systems with wastewater from cassava starch industry. Furthermore, the highest biogas productions were obtained for the highest VOC, while it was observed a bias on biogas production with VOC increase as well as the specific production of methane. / Dentre as diversas formas existentes de tratar os efluentes da indústria de fécula de mandioca, o processo anaeróbio é considerado uma alternativa simples e econômica, que alia o elevado grau de conversão da matéria orgânica à produção do biogás. O biogás, por sua vez, é um recurso energético potencial que pode ser utilizado para suprir parte das demandas energéticas das unidades industriais. Nesse sentido, estabeleceu-se como objetivo deste trabalho avaliar um reator anaeróbio de leito fixo e fluxo ascendente, em relação à remoção de carga orgânica da água residuária de extração de fécula de mandioca e à produção de biogás. Para isso, foram testadas as cargas orgânicas volumétricas (COV) de 2,5, 5,0, 8,0 e 10,0 g.L -1.d-1 em um reator de 2,82 L de volume útil. Utilizou-se meio suporte de anéis de polipropileno preenchidos com espuma de poliuretano. Os parâmetros monitorados no efluente do reator foram o pH, acidez volátil (AV), alcalinidade total (AT), razão AV/AT, concentrações de sólidos totais (ST), sólidos voláteis (SV), sólidos suspensos totais (SST), sólidos suspensos voláteis (SSV), demanda química por oxigênio total (DQOT) e demanda química por oxigênio solúvel (DQOS) e de ácidos orgânicos. A eficiência do reator foi avaliada em relação às remoções de sólidos e carga orgânica e à produção de biogás e de metano. Como principais resultados, observou-se que o reator manteve-se estável em relação aos parâmetros pH, remoção de SSV e remoções de DQOT e DQOS. Observou-se a presença de ácido lático, butírico, propiônico e acético no efluente, sendo o ácido acético em maiores concentrações. A produção média de biogás foi de 3,8 L.d-1 e a média da produção específica de biogás foi de 0,156 L.g-1DQOconsumida, sendo que, para ambos os maiores resultados foram obtidos para a COV 10,0 g.L-1.d-1. O percentual de metano no biogás variou de 66 a 84% e a produção específica de metano de 0,01 até 0,36 L.g-1 e os maiores valores foram obtidos nas COV 2,5 e 10,0 g.L-1.d-1, respectivamente. As remoções médias de ST, SV, SST e SSV foram de 72, 80, 63 e 92 %, respectivamente. As remoções médias de DQOT e DQOS foram de 98,7 e 97,9, respectivamente e as taxas de remoção mais altas foram obtidos para as COV 10,0 e 2,5 g.L-1.d-1 . Desta forma, conclui-se que é possível produzir biogás com percentuais de metano superiores a 80% (máximo) e remover a carga orgânica em mais de 90% (máximo), em sistemas com a configuração testada, utilizando água residuária de indústria de fécula de mandioca. Além disso, verificou-se que as maiores produções de biogás foram obtidas para as COV maiores e a tendência de aumento da produção de biogás com o aumento da COV, assim como a produção específica de metano.

A metilamina ('CH IND.3'NH IND.2') é um composto orgânico usado na produção de inseticidas, herbicidas, fungicidas, surfactantes, combustíveis fósseis, explosivos, produtos farmacêuticos, químicos fotográficos, tintas, tecidos, solventes, borrachas e anti-corrosivos. Estudos sobre tratamento de águas residuárias contendo metilamina são escassos e se restringem aos trabalhos envolvendo pesticidas carbamatados. Visando contribuir com os estudos acerca da degradação anaeróbia da metilamina, esta pesquisa estudou a comunidade microbiana e a atividade metanogênica específica em reatores anaeróbios em batelada, inoculados com lodo granular oriundo de reator UASB usado no tratamento de água residuária de abatedouro de aves, sob diferentes condições nutricionais: controle – sem metilamina, 5 mM, 10 mM, 20 mM, 30 mM, 50 mM, 75 mM e 90 mM de metilamina. Os reatores foram incubados sob temperatura de 30°C e agitação de 150 rpm. Desses reatores foram obtidas amostras para a determinação da atividade metanogênica específica (AME), sólidos suspensos voláteis (SVT), nitrogênio amoniacal e exames microscópicos. Ao final do experimento, foram realizados exames da biomassa por meio da técnica do número mais provável (NMP) e análise da diversidade microbiana por PCR/DGGE e seqüenciamento. O aumento da AME foi proporcional ao aumento das concentrações de metilamina, com inibição de produção de metano apenas nos reatores alimentados com 90 mM de metilamina. Os reatores alimentados com 50 mM e 75 mM de metilamina apresentaram os melhores resultados, com valores médios de AME de 0,0804 mmol 'CH IND.4'/g SVT.h e 0,0825 mmol 'CH IND.4'/g SVT.h respectivamente. Nos exames microscópicos foi verificado semelhança de morfologias microbianas em todas as concentrações de metilamina estudadas. Os organismos presentes nos reatores foram Methanosarcina sp., Methanosaeta sp., bacilos, coco-bacilos, filamentos e cocos. Em relação à análise de DGGE, não houve variação significativa nos padrões de bandas, tanto para o domínio Archaea quanto para o domínio Bacteria. Com os resultados da técnica de número mais provável (NMP) observou-se a predominância de arquéias metanogênicas dentre as bactérias anaeróbias totais. / The methylamine ('CH IND.3'NH IND.2') is an organic compound used in the production of insecticides, herbicides, fungicides, surfactants, fossil fuels, explosives, pharmaceuticals, photographic chemicals, paints, textiles, dyes, rubber and anticorrosive chemicals. Some studies about the treatment of wastewater containing methylamine are scarce and limited to works involving carbamate pesticides. This research aimed to study the anaerobic degradation of methylamine, the microbial community and the specific methanogenic activity in anaerobic battled reactors. The reactors were inoculated with granular sludge from a UASB reactor treating poultry wastes. Different nutritional conditions were adopted in the operation of the reactors: control (without methylamine), 5 mM, 10 mM, 20 mM, 30 mM, 50 mM, 75 mM and 90 mM of methylamine. The reactors were incubated under standard conditions: 30ºC and 150 rpm. Samples had been removed from the reactors to determine the specific methanogenic activity, the concentration of volatile suspended solids and ammoniacal nitrogen and the microscopic analysis. At the end of the experiment, the biomass was studied by the most probable number (MPN) technique and by the microbial diversity analysis with PCR and DGGE techniques. The increase of the specific methanogenic activity was proportional to the increase of methylamine concentration. The methane production was inhibited only in the reactor that was fed with 90 mM of methylamine. The reactors that were fed with 50 mM and 75 mM of methylamine showed the best results, with medium values of specific methanogenic activity equal to 0,0804 mmol 'CH IND.4'/g SVT.h and 0,0825 mmol 'CH IND.4'/g SVT.h, respectively. The microscopic analysis showed similarity between the microbial morphologies in all of the reactors. The observed microorganisms were Methanosarcina sp., Methanosaeta sp., rods, cocci and filaments. The DGGE analysis did not show significant variation in the standard profile of the Archaea and Bacteria domains. The results of the MPN technique revealed the predominance of the methanogenic archaea among the total anaerobic bacteria.

Despite general concern that the massive deposits of methane stored under permafrost underground and undersea could be released into the atmosphere due to rising temperatures attributed to global climate change, little is known about the methanogenic microorganisms in permafrost sediments, their role in methane emissions, and their phylogeny. The aim of this thesis was to increase knowledge of uncultivated methanogenic microorganisms in submarine and terrestrial permafrost deposits, their community composition, the role they play with regard to methane emissions, and their phylogeny. It is assumed that methanogenic communities in warmer submarine permafrost may serve as a model to anticipate the response of methanogenic communities in colder terrestrial permafrost to rising temperatures. The compositions of methanogenic communities were examined in terrestrial and submarine permafrost sediment samples. The submarine permafrost studied in this research was 10°C warmer than the terrestrial permafrost. By polymerase chain reaction (PCR), DNA was extracted from each of the samples and analyzed by molecular microbiological methods such as PCR-DGGE, RT-PCR, and cloning. Furthermore, these samples were used for in vitro experiment and FISH. The submarine permafrost analysis of the isotope composition of CH4 suggested a relationship between methane content and in situ active methanogenesis. Furthermore, active methanogenesis was proven using 13C-isotope measurements of methane in submarine permafrost sediment with a high TOC value and a high methane concentration. In the molecular-microbiological studies uncultivated lines of Methanosarcina, Methanomicrobiales, Methanobacteriacea and the Groups 1.3 and Marine Benthic from Crenarchaeota were found in all submarine and terrestrial permafrost samples. Methanosarcina was the dominant group of the Archaea in all submarine and terrestrial permafrost samples. The archaeal community composition, in particular, the methanogenic community composition showed diversity with changes in temperatures. Furthermore, cell count of methanogens in submarine permafrost was 10 times higher than in terrestrial permafrost. In vitro experiments showed that methanogens adapt quickly and well to higher temperatures. If temperatures rise due to climate change, an increase in methanogenic activity can be expected as long as organic material is sufficiently available and qualitatively adequate. / Trotz allgemeiner Bedenken, dass auf Grund des Temperaturanstieges im Zusammenhang mit der globalen Klimaerwärmung große Mengen des in terrestrischen und submarinen Permafrostsedimenten gespeicherten Methans freigesetzt werden könnte, ist bisher wenig über die in diesen Böden lebenden methanogenen Mikroorganismen, ihre Phylogenese und sowie ihre Bedeutung hinsichtlich der Methanemissionen bekannt. Das Ziel dieser Doktorarbeit war die Erweiterung der bisherigen Kenntnisse über unkultivierte methanogene Mikroorganismen in submarinen und terrestrischen Sedimentablagerungen, die Zusammensetzung ihrer Lebensgemeinschaft, ihrer Phylogenese und ihrer Bedeutung bei der Emission von Methan. Es wird vermutet, dass methanogene Gemeinschaften submarines Permafrostes zur Erstellung von Modellen genutzt werden können, um Aussagen bezüglich potenzieller Reaktionen methanogener Gemeinschaften des kälteren terrestrischen Permafrostes auf steigende Temperaturen, zu ermöglichen. Die Zusammensetzung der methanogenen Gemeinschaft wurde in terrestrischen und submarinen Permafrostproben untersucht. Der im Rahmen dieser Forschungsarbeit untersuchte submarine Permafrost wies eine im Vergleich zum terrestrischen Permafrost um circa 10°C höhere Temperatur auf. Mittels Polymerasenkettenreaktion (PCR) wurde von jeder der Proben DNA extrahiert und mittels weiterer molekular-mikrobiologischen Methoden wie DGGE, RT-PCR und Klonierung analysiert. Des Weiteren wurden die Proben für in vitro Experimente und Zellzählungen (DAPI und FISH) verwendet. Die Analyse der Isotopenzusammensetzung von CH4 in submarinen Permafrostsedimenten ließ einen Zusammenhang zwischen Methangehalt und aktiver in situ Methanogenese vermuten. Überdies konnte aktive Methanogenese, mittels 13C-Isotopenmessungen von Methan in submarinem Permafrostsediment mit hohem TOC-Wert und hoher Methankonzentration, bewiesen werden. Im Rahmen der molekular-mikrobiologischen Untersuchungen wurden in allen submarinen und terrestrischen Permafrostproben unkultivierte Linien von Methanosarcina, Methanomicrobiales, Methanobacteriacea und den Gruppen 1.3 und Marine Benthic von Crenarchaeota gefunden. Methanosarcina war in allen submarinen und terrestrischen Permafrostproben die dominierende Gruppe der Archaeen. Die Zusammensetzung der archaealen Gemeinschaft, insbesondere die Zusammensetzung der methanogenen Gemeinschaft, variierte zwischen den submarinen und terrestrischen Proben. Des Weiteren fand sich bei der Zellzählung der Methanogenen im submarinen Permafrost eine 10-fach höhere Zellzahl als im terrestrischen Permafrost. Die in vitro Experimente zeigten, dass Methanogene sich schnell und gut an höhere Temperaturen anpassen können. Im Falle weiter steigender Temperaturen auf Grund der Klimaveränderungen, kann – bei ausreichender Verfügbarkeit und Qualität organischen Materials – mit einer Zunahme der methanogenen Aktivität gerechnet werden.

<p>The anaerobic treatment of waste water has been studied with an emphasis on the Up- flow Anaerobic Sludge Blanket (UASB) reactor. A model to describe the processes occurring in a UASB reactor was developed and an experimental study of the anaerobic wastewater treatment systems in Nicaragua was also performed.</p><p>Experimental work was carried out in order to link the study to the wastewater treatment situation in Nicaragua, a developing country. In order to assess the performance of the treatment plants, the methanogenic activity of sludge from seven anaerobic wastewater treatment plants was first addressed. Due to a lack of Standards for the measurement of methanogenic activity, a laboratory method was developed based on the methods found in the literature. An additional aim of this study was to find adequate inoculum for the wastewater treatment plant in a brewery using an anaerobic reactor. Physic-chemical characteristics of the sludge were also determined to provide a basis for decisions regarding the agricultural employment of the sludge from the treatment plants.</p><p>A one-dimensional model describing the physical and biological processes occurring in an Up-flow Anaerobic Sludge Blanket reactor has been developed. These processes are advection, dispersion and reaction in the granule, including mass transport at the interface and diffusion within the particle. The advection-dispersion equation is used to describe these phenomena in the reactor. Dispersion is mainly caused by the gas bubbles rising up through the reactor and the granules in the ascending flow. The extent of the dispersion is expressed by the dimensionless Peclet (Pe) number. It is assumed that the biological degradation takes place at the surface and within the granules. The processes occurring in the granules formed by the microorganisms are described in detail; they include diffusion in the stagnant film around the granule, diffusion within the particle, and a degradation reaction. From these processes, the reaction term is analytically determined. The granules were modelled as spherical porous biocatalysts of different sizes. The biochemical degradation reactions were assumed to follow Monod type kinetics of the first order. For the numerical solution of the model, a standard program was used (Within MATLAB). The model was applied to some experimental data taken from the literature.</p><p>An important characteristic of the model is that it can simultaneously take into account reactions in granules of different sizes. At present, the parameters of the model are calculated using data from the literature; but experimental measurements of the main parameters are planned. The impact of the different parameters was studied by numerical simulation and its validity was tested using experimental data reported in the literature. The model could be a useful tool in the performance optimization of UASB reactors by predicting the influences of different operational parameters.</p>

Le méthane (CH4) est un des principaux gaz à effet de serre. L’élevage est à l’origine d’un tiers du CH4 produit par l’activité humaine en Europe. En plus, la production de CH4 représente une perte de 2% à 12 % de l’énergie consommée par l’animal. La méthanogenèse est le résultat de l’activité d’un groupe de microorganismes particuliers - les Archaea méthanogènes. La production de CH4 permet de d’éliminer du milieu ruminal l’hydrogène produit au cours de la fermentation des aliments par les autres microorganismes (bactéries, protozoaires, champignons). En effet, l’accumulation d’hydrogène affecte le fonctionnement optimal du rumen. La réduction des émissions de CH4 par les ruminants présente donc un intérêt économique et environnemental non négligeable et passe inévitablement par une modification de l’écosystème microbien du rumen. L’objectif de ce travail de thèse était de relier la production de CH4 avec la structure et l’activité de la communauté méthanogène du rumen. Différents modèles de manipulation de l’écosystème microbien ruminal comme la défaunation (élimination des protozoaires) et l’utilisation d’aliments connus pour modifier la méthanogenèse ont été utilisés. Le rumen étant un écosystème complexe, les interactions fonctionnelles entre les Archaea méthanogènes et les autres microorganismes présents (bactéries et protozoaires) ont également été étudiées. Dans cette optique, des outils de biologie moléculaire, permettant de cibler les principales communautés microbiennes, ont été optimisés. Nos travaux permettent de conclure sur l’absence de relation claire entre le nombre (et/ou la concentration) des Archaea méthanogènes et la méthanogenèse dans le rumen. Cependant les réductions des émissions de CH4 ont été attribuées aux changements dans la diversité de la communauté méthanogène et la disponibilité en hydrogène. Ce travail de thèse a mis en évidence que les modifications de la composition et/ou de l’activité métabolique de la communauté des Archaea méthanogènes seraient à l’origine des réductions des émissions de CH4 par les ruminants. Une meilleure connaissance des mécanismes microbiens impliqués dans la production de méthane permettra d’envisager de nouvelles pistes pour diminuer les émissions chez les ruminants. / Methane (CH4) is a major greenhouse gas. Livestock contributes to one third of CH4 produced by human activity in Europe. Methanogenesis is the result of the activity of a specific group of microorganisms, the methanogenic Archaea. This natural process prevents hydrogen accumulation in the rumen, which may affect the optimal feed degradation, but it represents a loss of 2% to 12% of energy consumed by the animal. Reduction of CH4 emissions from ruminants presents therefore economic and environmental benefits and inevitably involves a change in rumen microbial ecosystem. However microbial mechanisms of CH4 production in the rumen are still poorly understood. The objective of this thesis was to relate the production of CH4 with the structure and/or the activity of the methanogenic rumen community. Different models of manipulation of the rumen microbiota such as defaunation (removal of protozoa) and the use of feed known to affect methanogenesis were used. Interactions between methanogenic Archaea and other microorganisms (bacteria and protozoa) were also studied in the complex rumen ecosystem. In this context, tools of molecular biology, to identify key microbial communities, were optimized. Our work allows to conclude that there is no clear relationship between the number of methanogenic Archaea and methanogenesis rate in the rumen. However, reduction in CH4 emissions could be attributed to changes in the diversity of the methanogenic community and the availability of hydrogen. This thesis has shown that changes in the composition and / or metabolic activity of methanogenic Archaea community were associated to the reductions in CH4 emissions observed in our animal trials. A better understanding of microbial mechanisms involved in the production of methane will consider new ways to reduce emissions in ruminants.