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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Desinfecção de águas servidas através de tratamento térmico utilizando coletor solar / Disinfection of wastewater by heat treatment using solar collector

Ana Paula Alves Barreto Damasceno 17 November 2014 (has links)
O objetivo deste trabalho foi desenvolver um sistema de desinfecção de águas oriundas de esgotos domésticos, no qual seja aproveitado o calor gerado pelo sol, mantendo na água suas características químicas úteis às plantas. O experimento foi desenvolvido em duas etapas, a fim de se verificar sua viabilidade. A primeira etapa foi realizada em laboratório, com amostras de água coletadas no Ribeirão Piracicamirim. Utilizando-se um regulador automático de temperatura, foram realizados testes com o objetivo de verificar a redução de coliformes, sob as temperaturas de 45, 50, 55 e 60°C. Para os testes de quantificação e viabilidade dos ovos de helmintos foi feita a coleta de água residuária, proveniente da Estação de Tratamento de Esgoto (ETE) Piracicamirim. Ao ser encontrada a menor temperatura na qual ocorre a maior redução de coliformes, utilizou-se o mesmo regulador automático de temperatura e procederam-se os testes sob as temperaturas 60, 70, 80, 90 e 100°C, durante o período de 1 hora de exposição. A segunda etapa foi realizada em campo. Foi implantado um sistema composto por placa solar para o aquecimento da água e reservatórios, utilizando como principio a diferença de altura de carga entre os reservatórios de entrada e saída para que a água atingisse a temperatura necessária. Nesta etapa, foram utilizados três reservatórios. No 3° reservatório, foi instalado um mecanismo que permitiu que o tubo conectado a caixa fosse movimentado de modo a ficar mais alto ou mais baixo, de acordo com a temperatura desejada. As amostras onde objetivou-se verificar presença e viabilidade de ovos de helmintos foram submetidas ao processo de separação de resíduos que permitiu posteriormente análise ao microscópio. Ao término do experimento foi realizada a comparação dos resultados e observou-se que nas temperaturas de 55°C e 60°C, o tempo de uma hora foi eficiente para eliminar tanto coliformes totais como Escherichia coli presentes nas amostras em comparação à amostra de caracterização da água testada. Diante disso, realizaram-se testes reduzindo o tempo de exposição das amostras, obtendo-se como resultado o tempo mínimo de 15 minutos à temperatura de 60°C para que fosse alcançado o mesmo resultado obtido com uma hora de exposição. Nas amostras que foram submetidas ao tratamento e incubadas, apenas na amostra submetida a 60°C foi possível a observação de um ovo de helminto, que se verificou infértil. Nas demais amostras correspondentes aos outros tratamentos, não foi possível a recuperação de ovos de helmintos nas lâminas observadas. É possível que durante o processo de limpeza para redução de resíduos nas amostras tenha ocorrido perda de material devido à desintegração da matéria orgânica presente. Diante dos resultados obtidos, pôde-se chegar à conclusão que, apesar do sistema de desinfecção não ter apresentado os resultados esperados, ele atendeu ao objetivo proposto. O sistema deve ser aprimorado para que se chegue a um modelo em que, possa ser utilizado de maneira segura o aproveitamento de águas residuárias para uso em diversos sistemas de irrigação para a agricultura. / The objective of this study was to develop a water disinfection system originated from domestic sewage, which is harnessed the heat generated by the sun, keeping the water their chemical characteristics useful to plants. The experiment was conducted in two stages, in order to verify its viability. The first step was performed in the laboratory, with water samples collected in Piracicamirim brook. Using an automatic temperature regulator, tests were performed in order to verify the reduction in coliform, at temperatures of 45, 50, 55 and 60°C. For the tests of quantification and viability of helminth eggs was made to collect wastewater from the Wastewater Treatment Station (WWTS) Piracicamirim. When found to be the lowest temperature at which happens the greatest reduction in coliform, we used the same automatic temperature regulator and the tests were carried at temperatures 60, 70, 80, 90 and 100°C for a period of 1 hour exposure. The second stage was conducted in the field. A system comprising solar panel to heat the water tank, using principle as the load height difference between the inlet and outlet reservoirs for the water to reach the required temperature has been deployed. In this step, three reservoirs are used. On the 3rd tank was installed a mechanism that allowed the tube to be connected to the box so as to be moved higher or lower, according to the desired temperature. Samples where the objective was to verify the presence and viability of helminth eggs were submitted to the waste separation process which subsequently allowed analysis under the microscope. At the end of experiment was performed to compare the results and it was observed that at temperatures of 55°C and 60°C, the time of one hour was effective to eliminate both total coliforms and Escherichia coli in the samples compared to the sample characterization of the test water. Therefore, tests were conducted by reducing the exposure time of the samples, obtaining as a result a minimum of 15 minutes at a temperature of 60°C time for which achieved the same result was obtained with a one hour exposure. In the samples that were subjected to treatment and incubated, only in the sample treated at 60°C was possible to observe a helminth egg it was found infertile. In the other samples corresponding to other treatments, recovery of helminth eggs in the observed blades was not possible. It is possible that during the cleaning process for waste reduction has occurred in the samples loss of material due to disintegration of the organic matter. Based on these results, we could conclude that despite the disinfection system not producing expected results, he met the objective. The system should be improved in order to arrive at a model that can be used safely harnessing wastewater for use in various irrigation systems for agriculture.
62

Qualidade da água por indicadores ambientais e análise da resistência de E. coli isoladas em águas superficiais urbanas / Water quality through environmental indicators and analysis of E. coli resistance isolated in urban surface waters

Malagi , Ivair 20 February 2018 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2018-06-25T13:50:49Z No. of bitstreams: 2 IVAIR MALAGI.pdf: 884398 bytes, checksum: 2a11b4469ff506f41317eea546df7e21 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-06-25T13:50:49Z (GMT). No. of bitstreams: 2 IVAIR MALAGI.pdf: 884398 bytes, checksum: 2a11b4469ff506f41317eea546df7e21 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The aquatic ecosystems of urban rivers are affected by the disposal of waste from the sewage network. In the present research, the water quality of six rivers of the city of Cascavel - PR, being the rivers Cascavel, Quati, Bezerra, Antas, Lageado Clarito and Amambay. The collections conducted from March to November 2017 were used microbiological, physico-chemical and susceptibility/resistance of strains of Escherichia coli to antimicrobials. For coliforms it was followed the methodology described by Silva et al. (1997), the physical-chemical parameters performed with the Horiba manual probe end the susceptibility antimicrobial was evaluate accoording with the recomendations of Clinical and Laboratory Standards Institute (2015). There were significant differences between the months evaluated for the physico-chemical, microbiological and resistance parameters. Among the parameters evaluated just oxygen dissolved, solid total and biochemical oxygen demand, don't were significant. All the six rivers evaluated exceed the limit (<10MNP/mL) for coliforms thermotolerant. Was observed that 55.5% of strains of Escherichia coli were resistent at least one antimicrobial and 14.4% presented multiresistence. The major resistances were to ampicillin, amoxicillin and tetracycline with 21.1, 16.6 and 20% respectively. The result of this search contributing for an evaluation of caution associated with contamination of the waters by sewage, with bacterias highly resistant to antimicrobial on the urban center rivers. / Os ecossistemas aquáticos de rios urbanos são afetados pelo descarte de resíduos da rede de esgoto. Na presente pesquisa, foi avaliada a qualidade da água de seis rios da cidade de Cascavel – PR, sendo eles: Rio Cascavel, Rio Quati, Córrego Bezerra, Rio das Antas, Lageado Clarito e Sanga Amambay. As coletas realizadas no período de março a novembro de 2017 utilizaram-se indicadores microbiológicos, físico-químicos e a suscetibilidade/resistência das cepas de Escherichia coli a antimicrobianos. Para coliformes seguiu-se a metodologia descrita por Silva et al. (1997), os parâmetros físico-químicos realizados com a sonda manual Horiba e a suscetibilidade antimicrobiana foi avaliada de acordo com as recomendações de Clinical and Laboratory Standards Institute (2015). Houve diferenças significativas em entre os meses avaliados para os parâmetros físico-químicos, microbiológicos e para resistência. Dentre os parâmetros avaliados apenas oxigênio dissolvido, sólidos totais e demanda bioquímica de oxigênio, não foram significativos. Todos os seis rios analisados excedem o limite (<10 NMP/mL) para coliformes termotolerantes. Foi observado que 55,5% das cepas de Escherichia coli foram resistentes a pelo menos um antimicrobiano e 14,4% apresentaram multirresistência. As maiores resistências foram para ampicilina, amoxicilina e tetraciclina com 21,1, 16,6 e 20%, respectivamente. Os resultados dessa pesquisa contribuem para uma avalição dos perigos associados com a contaminação das águas por esgoto juntamente com bactérias resistentes aos antimicrobianos em rios de centros urbanos.
63

Comparação de metodologias para a estimativa do número mais provável (NMP) de coliformes em amostras de água / Comparison of methodologies for estimating the most probable number (MPN) of coliform in water samples

Marina Chiarelli Marquezi 24 September 2010 (has links)
Em quase todos os ambientes aquáticos são encontrados diversos microrganismos, entre eles alguns patogênicos ao homem, que tem como rota de transmissão o ciclo fecal-oral. Pelo fato de a água ser o alimento mais consumido pela população, ela está associada a diversos casos de doenças e de riscos à saúde pública. Assim, o controle da qualidade da água antes do seu consumo é essencial, e para a garantia de sua qualidade devem ser feitas análises que buscam indicar a contaminação por material de origem fecal. O grupo de bactérias mais usado para a determinação de contaminação fecal é o grupo coliformes totais, que tem como subgrupo os coliformes termotolerantes. A bactéria Escherichia coli é integrante do grupo coliforme termotolerante, e é a mais indicada para determinação de contaminação fecal pelo fato de estar presente em grande quantidade em fezes de humanos e animais de sangue quente. Para a análise de bactérias do grupo coliformes totais e E. coli há diversos métodos, entre eles o método convencional de fermentação em tubos múltiplos (FTM) e os métodos rápidos Colilert e Colitag. Este trabalho teve como objetivo comparar estes três métodos para tais análises em amostras de água provenientes de pontos com contaminações distintas (abastecimento, bica e rio), assim como comparar as contagens encontradas de coliformes termotolerantes e E. coli pelo método FTM. Os métodos rápidos Colilert e Colitag se mostraram equivalentes ao FTM nas análises de coliformes totais em amostras de água provenientes de bica e de abastecimento, e nas análises de E. coli em amostras de água de abastecimento, da bica e do rio. Para as análises de coliformes totais em amostras de água do rio o método FTM apresentou uma diferença significativa em relação ao método Colilert e Colitag. Ambos os métodos rápidos não diferiram entre si. A diferença encontrada entre estes métodos nestas análises pode ter ocorrido devido à presença de Aeromonas nas amostras, que podem ter gerado resultados falso-positivos nos métodos rápidos, superestimando a contagem de coliformes totais; ou pela maior capacidade dos métodos rápidos em recuperar células injuriadas de coliformes totais, detectando uma quantidade maior destas bactérias. Na comparação das contagens encontradas para coliformes termotolerantes e E. coli nas mesmas amostras foi encontrada uma diferença significativa. Este resultado é explicado pelo fato de o grupo coliforme termotolerante incluir bactérias de origem não exclusivamente fecal, tais como Enterobacter e Klebsiella, o que pode superestimar a contaminação fecal da amostra. Já a E. coli tem origem exclusivamente fecal, sendo mais indicada para tal análise. Assim, como os métodos rápidos se mostraram equivalentes ao método convencional estudado, devese preferir o uso dos métodos rápidos, que dão o resultado em 24 horas, indicando a qualidade da água a tempo de evitar o uso desta pela população. Na escolha entre as bactérias do grupo coliformes termotolerantes e a E. coli para a indicação da contaminação fecal, deve-se preferir o uso da E. coli. / In almost all aquatic environments are found in various microorganisms, including some pathogenic to man, which route of transmission is the fecal-oral cycle. Because the water is the food most consumed by people, it is associated with several cases of diseases and risks to public health. Thus, control of water quality prior to consumption is essential, and to guarantee its quality must be made analysis seeking to indicate contamination by fecal material of origin. The group of bacteria most commonly used for the determination of fecal contamination is the total coliform group, which has as subgroup thermotolerant coliforms. The bacterium Escherichia coli is a member of the group thermotolerant coliform, and is most suitable for determination of fecal contamination by being present in large quantities in feces of humans and warmblooded animals. For the analysis of bacteria of the group coliform and E. coli there are several methods, including the conventional method Multiple Tube Fermentation (MTF), and the rapid methods Colilert and Colitag. This study aimed to compare these three methods for analysis in water samples from different points with different contamination (supply, fountain and river) and compare the count found for thermotolerant coliform and E. coli by the method FTM. The methods Colilert, Colitag and FTM were equivalent in the analysis of total coliform in water samples from the fountain and supply, and the analysis of E. coli in samples of supply, fountain and river. For analysis of total coliform in water samples from the river, FTM method showes a significant difference compared to the methods Colilert and Colitag. Both rapid methods did not differ. The difference between these methods in these tests may be due to the presence of Aeromonas in the samples, which may have generated false-positive results in rapid methods, overestimating the total coliform count; or the largest capacity of rapid methods in recovering injured cells of coliforms, detecting a larger amount of these bacteria. Comparing the scores found for thermotolerant coliform and E. coli in the same samples was found a significant difference. This result is explained by a thermotolerant coliform group include bacteria not exclusively fecal origin, such as Klebsiella and Enterobacter, which may overestimate the faecal contamination of the sample. Since E. coli is exclusively fecal origin, being more suitable for such analysis. So, as rapid methods showed to be equivalent to the conventional method studied, one should prefer the use of rapid methods that give results in 24 hours, indicating the water quality in time to prevent its use in the population. In choosing between coliform thermotolerant bacteria and E. coli for the indication of fecal contamination, it is preferable to use E. coli.
64

Seasonal trends and sampling time of day on overall microbial population and indicator organisms in catfish parts and catfish processing environment

Hidalgo-Sindoni, Maria Gabriela 09 December 2022 (has links) (PDF)
Commercial production of catfish is the leading aquaculture industry in the United States. Production in Mississippi, Louisiana, Alabama, and Arkansas representing 96% of the total catfish sales in the USA. In 2017, the USDA-FSIS added testing of generic Escherichia coli and Enterococcus to the sampling of Siluriformes. The incidence of Escherichia coli in fish and seafood has been associated with possible fecal matter contamination. However, this indicator bacteria could also be a part of the natural microflora of catfish ponds where processing plants collect hybrid catfish. Aerobes, Psychrotrophs, Coliforms, Escherichia coli, and Enterobacteriaceae counts among environmental, liquid and fish samples were tested every season and periodically during one day of operation. Generic Escherichia coli counts were greater in late Summer (P ≤ 0.05) for liquid samples (1 log CFU/g) . During the day, Escherichia coli appeared to be more recurrent in the afternoon at the skinning step (P ≤ 0.05).
65

Microbial and Chemical Affects on Leachate from Calcareous Soils Treated with Wastewater Effluent

Paul, Craig M. 06 July 2005 (has links) (PDF)
Increasing human populations are placing greater strain on water resources, prompting the use of treated wastewater effluent for irrigation in some areas, including the desert regions of the Western United States. To determine the potential effects of using secondary effluent for irrigation, we applied wastewater effluent and irrigation waters to natural and artificially constructed calcareous soils in greenhouse and field lysimeters, and in soil columns. The leachate from one field lysimeter contained increased fecal coliform counts than the effluent. Leachate coliform counts were decreased or not significantly changed in two field lysimeters. Electrical conductivity (EC), sodium adsorption ratio (SAR), chloride and nitrate concentrations also increased significantly in the leachate of the three field lysimeters however. Samples collected from the greenhouse lysimeters showed a significant decrease in all categories except EC, was not significantly changed. Soil column drainage samples showed a decrease in coliform counts, and increase in EC and chloride levels while SAR and nitrate levels varied with clay content. Preferential flow of coliform bacteria and high EC and SAR values could indicate long term effects that may affect the sustainability of the practice.
66

Practical use and development of biomérieux TEMPO® system in microbial food safety

Alsaadi, Yousef Saeed January 1900 (has links)
Doctor of Philosophy / Department of Food Science / Daniel Y.C. Fung / In the food industry, coliform testing is traditionally done by the time consuming and labor intensive plate count method or tube enumeration methods. The TEMPO® system (bioMérieux, Inc.) was developed to improve laboratory efficiency and to replace traditional methods. It uses a miniaturization of the Most Probable Number (MPN) method with 16 tubes with 3 dilutions in one single disposable card. It utilizes two stations: the TEMPO® Preparation station and the TEMPO® Reading station. In this study, the Oxyase® (Oxyase®, Inc.) enzyme was added to TEMPO® CC (Coliforms Count), TEMPO® AC (aerobic colony count) and TEMPO® EC (E. coli Count) methods. Water samples of 1 ml with 0.1 ml of Oxyase® enzyme were compared to samples without the Oxyase® enzyme using the TEMPO® system. Samples were spiked with different levels of coliforms (10, 102, 103 and 104 CFU/ml), stomached (20 sec), and pipetted into the three different TEMPO® media reagents (4 ml) in duplicate and then automatically transferred into the corresponding TEMPO® cards by the TEMPO® preparation station. Counts were obtained using the TEMPO® reading station after 8, 12, 16, 22 and 24 hours at an incubation temperature of 35°C. Results from 20 replicates were compared statistically. Using TEMPO® tests, high counts in food samples (>6 log 10 CFU/ml) can be read in 6±2 hours of incubation using the time-to-detection calibration curve. The TEMPO® system reduces reading time (reading protocol should be changed). There is no need to wait for 22 hours of incubation only 12 hours is required. Oxyrase® enzyme is not needed for the TEMPO® system.
67

Pesquisa de Escherichia coli produtora de Shiga toxina (STEC) em carcaças de aves comercializadas no município de Xanxerê-SC

Cerutti, Marisete Fochesatto January 2018 (has links)
O consumo crescente de carne de aves requer uma contínua atenção na provisão de alimentos seguros para o consumidor. Entre os agentes emergentes de relevância para a Saúde Pública destaca-se a Escherichia coli produtora de Shiga toxina (STEC), causadora de severa colite hemorrágica e síndrome urêmica hemolítica. Apesar da importância deste microrganismo na carne de ruminantes, sua presença em carne de aves tem sido pouco investigada. O presente estudo teve como objetivo avaliar a ocorrência de STEC em carcaças de aves congeladas comercializadas na cidade de Xanxerê/SC. Um total de 246 carcaças adquiridas em oito supermercados da cidade, de acordo com a disponibilidade na gôndola, foi submetido à rinsagem individual com água peptonada tamponada 1% e submetida à enumeração de coliformes totais e Escherichia coli e pesquisa de STEC pelo protocolo descrito na ISO/TS 13136:2012(E). Após 24 horas de incubação de uma alíquota da rinsagem a 36°C, foi realizada a pesquisa de genes de virulência (stx1, stx2 e eae) por PCR multiplex. Das carcaças amostradas, a maioria era frango “in natura” (57%), seguidos de galinha (16%), galeto (15%), frango temperado (11%) e frango caipira (2%). A enumeração de coliformes totais no líquido de rinsagem resultou em mediana de 5,2 UFC.g-1 (variando de 1 a 2.836,1 UFC.g-1) e de Escherichia coli foi 0,6 UFC.g-1 (variando de 1 242 UFC.g-1), demonstrando uma qualidade higiênico-sanitária satisfatória do produto. Todos os líquidos de rinsagem originados das 246 carcaças avaliadas foram negativos para os genes stx1 e stx2, indicando ausência de STEC nas amostras. Em 12 carcaças (4,88%) foi confirmada a presença de E.coli eae+, indicando a presença do patotipo enteropatogênico (EPEC). Conclui-se que as carcaças de aves comercializadas em Xanxerê apresentam um padrão higiênico sanitário adequado e ausência de STEC considerando uma prevalência detectável de 1,5% na amostra analisada. Por outro lado, detectou-se a presença de EPEC, a qual deve ser investigada para caracterizar as cepas encontradas em termos de potencial importância para a saúde do consumidor. / The increasing consumption of poultry meat requires continued attention in the provision of safe food for the consumer. Emerging agents of relevance to Public Health include Shiga toxin-producing Escherichia coli (STEC), which causes severe hemorrhagic colitis and hemolytic uremic syndrome. Despite the importance of this microorganism in beef, its presence in poultry meat has been few investigated. The present study aimed to evaluate the occurrence of STEC in frozen poultry carcasses marketed in the city of Xanxerê/SC. A total of 246 carcasses purchased from eight city supermarkets, according to on-shelf availability, was submitted to individual rinsing with 1% buffered peptone water and submitted to enumeration of total coliforms and Escherichia coli and STEC detection by the protocol described in ISO / TS 13136: 2012 (E). After 24 hours of incubation at 36 ° C an aliquot of the rinsing, virulence gene (stx1, stx2 and eae) were investigated by multiplex PCR. Of the carcasses sampled, the majority were fresh poultry meat (57%), followed by chicken (16%), young chicken (15%), seasoned poultry meat (11%) and “caipira”type chicken (2%). The enumeration of total coliforms in the rinsing liquid resulted in a median of 5.2 CFU.g-1 (ranging from 1 to 2836.1 CFU.g-1). The median of Escherichia coli was 0.6 CFU.g-1 (ranging from 1 to 242 CFU.g-1), demonstrating a good sanitary and hygienic quality of the product. All rinse liquids from the 246 carcasses tested were negative for the stx1 and stx2 genes, indicating absence of STEC in the samples. In 12 carcasses (4.88%) the presence of E.coli eae + was confirmed, indicating the presence of the enteropathogenic pathotype (EPEC). It is concluded that the poultry carcasses marketed in Xanxerê have an good hygienic sanitary standard and absence of STEC considering a detectable prevalence of 1.5% in the sample analyzed. On the other hand, we detected the presence of EPEC, which should be further investigated to characterize the strains in terms of potential importance for consumer health.
68

Aspectos limnológico-sanitários das águas do rio Caulim, na região metropolitana de São Paulo / Sanitary and limnologic aspects of the water from the Caulim river, in the metropolitan region of São Paulo.

Boneto, Renata Mendes Cardoso Garcia 31 August 2007 (has links)
Introdução: A água é um recurso essencial para a vida dos seres vivos e tem sofrido grande deterioração devido principalmente, à ação antrópica. O Rio Caulim está situado no sub-distrito de Parelheiros, onde a ocupação se deu de forma descontrolada e inadequada e vem recebendo o esgoto doméstico dos loteamentos clandestinos da região. Como deságua na Represa do Guarapiranga, importante manancial de abastecimento da Região Metropolitana de São Paulo, seu estudo torna-se importante. Objetivo: Analisar as condições ecológico-sanitárias do Rio Caulim; avaliar parâmetros físicos, químicos e microbiológicos do Rio Caulim; verificar a variação temporal e espacial desses parâmetros; conhecer as possíveis relações da qualidade da água com a ocupação do solo; e fornecer subsídios para as autoridades tomarem medidas de recuperação e preservação da qualidade das águas do Rio Caulim. Métodos: Em seis pontos ao longo do rio foram analisadas variáveis abióticas (temperatura do ar e da água, profundidade, transparência, oxigênio dissolvido, pH, condutividade, cor, turbidez, sólidos totais e suspensos, demanda bioquímica de oxigênio, nitrogênio total e amoniacal, fósforo total e ortofosfato total) e variáveis bióticas (coliformes totais e termotolerantes). Essas foram analisadas quanto a variação espaço/temporal e realizou-se o teste de correlação de Spearmam para verificar a relação existente entre as variáveis. Resultados: Os valores encontrados para condutividade (182 a 783 ?S), turbidez (11 a 160 UNT), demanda bioquímica de oxigênio (5 a 202 mg/L O2), nitrogênio total (7 a 93 mg/L N), nitrogênio amoniacal (2 a 36 mg/L N), fósforo total (0,1 a 9 mg/L P), orto-fosfato 0,1 a 5 mg/L P), coliformes totais (105 a 107 NMP) e coliformes termotolerantes (104 a 107 NMP), foram altos e os valores encontrados para oxigênio dissolvido (0,4 a 5,6 mg/L O2) foram baixos. Os pontos apresentaram diferenças quanto aos valores encontrados para as variáveis analisadas, sendo os pontos que se encontram próximos às áreas mais densamente (pontos 2 e 4) habitadas os mais comprometidos e o ponto 1, que fica na área da nascente, também bastante comprometido devido à precariedade das fossas sépticas das residências ali existentes. Conclusão: O rio Caulim está perdendo suas características de um ambiente lótico, devido à grande influência antrópica, tais como, o lançamento de esgoto, lixo e entulho e retirada da mata ciliar, apresenta baixa capacidade de autodepuração e encontra-se em desconformidade com a legislação vigente (CONAMA 357/05) para classe 1. / Sanitary and limnologic aspects of the water from the Caulim river, in the metropolitan region of São Paulo. Introduction: Water is essential to all the living beings and has been deteriorated mainly by antropic action. The Caulim river is situated in the District of Parelheiros, which was occupied without control, receiving all the domestic sewage dump from the people living clandestinely and also illegally in the neighborhood. As it is an important contribution to Guarapiranga Reservoir, which means a very important drinking water resource for the Metropolitan Region of São Paulo, its study is very necesssary. Objective: To analyze the ecological and sanitary conditions of the river; to verify the temporary and spatial variation of this information; to know the relationship between the water quality and the soil occupation, giving to the authorities subsidies for a managing plan to assure all the efforts to save the river preserving its water quality. Methods: In six sampling points along the river, abiotic variables (air and water temperature, water depth, transparency, dissolved oxygen, pH, conductivity, colour, turbidity, total and suspended solids, biochemical oxygen demand, total nytrogen and ammonia, total phosphorus and total ortophosphate) and biotic variables (total and thermotolerant coliforms) were analyzed considering the space/temporal variation, and correlation test was run to verify their relationship. Results: The values for conductivity (182 - 783 ?S), turbidity (11 - 160 UNT), biochemical oxygen demand (5 - 202 mg/L O2), total nytrogen (7 - 3 mg/L N), ammoniacal nytrogen (2 - 36 mg/L N), total phosphorus (0,1 - 9 mg/L P), ortophosphate (0,1 - 5 mg/L P), total coliforms (105 - 107 NMP) and thermotolerant coliforms (104 - 07 NMP) were high, and the results of the dissolved oxygen (0,4 - 5,6 mg/L O2) were low. The sampling points showed differences concerning the values considered for the analyzed variables; the more populated areas (points 2 and 4) were more damaged, and point 1, which is situated near the riverhead, is also highly polluted due to the domestic sewage dumped from poor septic tanks. Conclusion: The Caulim river is losing its characteristics of a lotic environment, due to the enormous anthropogenic influence, such as the solid wastes and sewage dumped and also removal of the ciliar forest, therefore showing low capacity of selfpurification, and non-compliance with current laws (CONAMA 357/05) to class 1.
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Influência dos coliformes no comportamento de Listeria monocytogenes em queijo Minas frescal / Influence of coliformS in the behavior of Listeria monovytogenes in fresh white Minas cheese.

Aragon-Alegro, Lina Casale 30 November 2007 (has links)
Os queijos macios são veículos conhecidos de surtos de listeriose. Os chamados \'queso blanco\' ou \'Latin-style fresh cheese\' representam um grupo heterogêneo de queijos macios brancos e não maturados produzidos e consumidos em diferentes países da América Latina. O queijo Minas Frescal é o representante brasileiro deste grupo e pode ser produzido utilizando-se diferentes tecnologias. Vários estudos têm mostrado que a ocorrência de Listeria monocytogenes (Lm) em queijo Minas Frescal é muito variável, enquanto altas populações de coliformes fecais (>104UFC/g) são muito comuns. O objetivo deste trabalho foi avaliar a influência dos coliformes no comportamento de Lm em queijo Minas Frescal produzido por acidificação direta do leite com ácido lático e por adição de cultura lática. Leite pasteurizado foi contaminado com Lm (106UFC/g e 1UFC/g) e coliformes (107UFC/g) e os queijos foram preparados seguindo-se os procedimentos de fabricação comerciais. Queijos preparados com leite contaminado somente com Lm (106CFU/g e 1CFU/g) ou coliformes (107UFC/g) foram utilizados como controle. As produções foram repetidas 3 vezes. Os queijos embalados em sacos de polietileno foram divididos em três grupos, sendo cada um estocado em uma das seguintes condições: 20 dias a 5oC; 20 dias a 12oC (temperatura de abuso); 8 dias a 5oC/16h seguido por 25oC/8h (para simular condições em feiras-livres). A cada 5 dias para os queijos armazenados a 5oC e 12oC, e a cada 2 dias para o outro grupo, duplicata de amostras foram retiradas e as populações de Lm, coliformes e bactérias láticas foram determinadas utilizando-se procedimentos padrões. pH e atividade de água também foram mensurados. A inibição de Lm foi observada nos queijos em que os coliformes estavam presentes (pelo menos 1 log de diferença em cada temperatura, com exceção dos queijos preparados com ácido lático e estocados com alternância de temperaturas). Os valores de pH e aw não foram suficientemente baixos para causarem essa inibição, entretanto, a acidez titulável foi maior em queijo contendo coliformes. Testes em ágar tripticase de soja (TSA) contendo diferentes concentrações de ácido lático e contaminados com Lm (106UFC/g e 1UFC/g) mostraram que, quando altas concentrações de ácido lático foram utilizadas (0,3% ou mais), a população de Lm não aumentou, indicando que o ácido lático produzido pelos coliformes pode ser um fator importante no controle de Lm em queijo Minas Frescal. É importante ressaltar que não é nossa intenção utilizar coliformes para inibir Lm nesse tipo de queijo. / Soft cheeses are a well known cause of listeriosis outbreaks. The so called \'queso blanco\' or \'Latin-style fresh cheese\' represents a heterogeneous group of white, unripened soft cheese produced and consumed in different Latin America countries. Minas Frescal cheese is the Brazilian representative of this group and it can be produced by different technologies. Several studies have shown that Listeria monocytogenes (Lm) occurrence in Minas cheese is highly variable, while high population of fecal coliforms (>104CFU/g) is very common. The objective of this study was to evaluate the influence of coliforms in the behavior of Lm in Minas Frescal cheeses produced by direct acidification of the milk with lactic acid and by the addition of a lactic culture. Pasteurized milk was spiked with Lm (106CFU/g and 1CFU/g) and coliforms (107CFU/g) and the cheeses were lab prepared following regular commercial procedures. Cheeses prepared with milk spiked only with Lm (106CFU/g and 1CFU/g) or coliforms (107CFU/g) were used as controls. The production had been repeated 3 times. The cheeses packed in polyethylene bags were divided in 3 groups and each group was stored in one of the following conditions: up to 20 days at 5oC; up to 20 days at 12oC (abuse temperature); up to 8 days at 5oC/16h followed by 25oC/8h (to simulate open market conditions). Every 5 days for cheeses stored at 5oC and 12oC, and every 2 days for the other group, duplicate samples were taken and Lm, coliforms and lactic acid bacteria population were determined using standard procedures. pH and water activity were also measured. An inhibition of Lm was observed in the cheeses when in the presence of coliforms (at least 1 log difference at any temperature, except cheeses prepared with lactic acid and stored with temperature alternation). The values of pH and aW had not been sufficiently low to cause this inhibition, however, the titratable acidity was higher in cheeses containing coliforms. Tests in tryptone soy agar containing different concentrations of lactic acid and spiked with Lm (106CFU/g and 1CFU/g) showed that when higher concentrations of lactic acid were used (0.3 % or more), the population of Lm did not increase, indicating that the lactic acid produced by coliforms may be an important factor in controlling Lm in Minas Frescal cheese. It is important to ressaltar that it is not our intention to use coliforms to inhibit Lm in this type of cheese.
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Water Quality Indicators in Watershed Subbasins with Multiple Land Uses

Aull, Malia Elizabeth 03 May 2005 (has links)
The wide use and accessibility of surface waters leads to multiple sources of contamination. The two main forms of pollution are from point and nonpoint sources. Point sources are regulated by the federal government; however, nonpoint sources are more difficult to regulate since there is no defined origin. Due to this problem, surface water monitoring is performed by state agencies which can include the testing of several different water quality indicators chosen by the state. This thesis examines several water quality indicators from two watershed subbasins with different land uses. The types of contamination and sources were evaluated from the data, which was analyzed based on sampling site, season, and two statistical tests. The water quality indicators that were examined in this study included physical, chemical, and microbiological indicators. The two subbasins that were monitored were located in the Wachusett reservoir watershed in central Massachusetts. One subbasin, Malagasco Brook, was located south of the reservoir. Six sampling sites were chosen in proximity to a swampy area, a nursery, and condominium housing complex. The second subbasin, Beaman Pond, was located to the northwestern side of the reservoir and was monitored at three sites. These sites were located in a residential area in addition to a special use two acre farm. Analyses were performed by site and by season to find trends in the data. Statistical correlation and ANOVA analyses were performed in order to better understand the relationships of the water quality indicators. From these analyses, it was determined that organic carbon and human sources of contamination were significant in the Malagasco Brook subbasin. Organics originated in the headwaters and nursery area, and the residential area was a possible source of microorganisms. The Beaman Pond subbasin was found to be affected by both human and animal sources of contamination. Downstream of the farm, animal contamination was found and supported by measurement of microbial source tracking indicators. The other two sites were affected by human sources, a result of septic systems. Strong correlations were found between several water quality parameters, including temperature and dissolved oxygen, turbidity and particle counts, and fecal coliforms and enterococcus. Based on data usefulness and ease of measurement, it is recommended that temperature, DO, conductivity, pH, dissolved organic carbon, turbidity or particle counts, and fecal coliforms be included in a routine watershed monitoring program.

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