Solarização é uma alternativa para desinfecção de águas residuárias, pois a ação conjunta dos raios solares e da temperatura tende a inibir o crescimento de microrganismos. O objetivo desta pesquisa é verificar a eficácia do método na redução de microrganismos patogênicos em amostras de efluente doméstico. O experimento foi desenvolvido em condições de campo nos meses de julho, agosto, outubro e dezembro de 2006 e março e julho de 2007, na área da estação meteorológica localizada na Fazenda Piloto da Universidade de Taubaté. A análise de coliformes fecais e a leitura de turbidez foram realizadas no laboratório de Microbiologia Agrícola e Fitopatologia do Departamento de Ciências Agrárias da Universidade de Taubaté. A temperatura do ar e a intensidade da radiação solar total acumulada foram fornecidas pela Plataforma de Coleta de Dados (PCD) uma parceria UNITAU e INPE através do Programa de Monitoramento Ambiental da Região do Eixo Rio-São Paulo. As amostras de efluentes foram condicionadas em 20 garrafas transparentes com capacidade para 2L tipo PET (Politereflato de Etileno), depois submetidas aos seguintes procedimentos: sem exposição ao sol e com 2, 4, 6 e 8 horas de exposição ao sol, com 4 repetições cada, totalizando 20 recipientes. A eficiência do tempo de exposição foi determinada pela quantificação do Número Mais Provável (NMP) para coliformes fecais nas amostras de efluentes. Quanto ao resultado podese observar que a exposição do efluente a radiação solar reduziu a ocorrência de coliformes fecais, na medida em que se aumentou o tempo de exposição. Sendo que para 2 horas de exposição à radiação solar houve uma redução média de 51,2% e com 8 horas de exposição essa média aumentou para 84% de redução para coliformes fecais. De acordo com os resultados pôde-se concluir que a solarização poderá ser utilizada para reduzir microrganismos patogênicos no efluente doméstico. / Solarization is an alternative method for disinfection of wastewater, therefore the joint action of the solar rays and the temperature tends to inhibit the growth of microorganisms. The objective of this research is to verify the effectiveness of the method for the reduction of pathogenic microorganisms in domestic effluent samples. The experiment was developed in field conditions during the months of August, October and December of 2006 and March and July of 2007, in the area of the meteorological station located in the Pilot Farm of the University of Taubate. The fecal coliform counts and the turbidity readings were performed in the Agricultural Microbiology and Phytopathology Laboratory of the Agrarian Sciences Department of the University of Taubate. The air temperature and the intensity of the accumulated total solar radiation had been supplied by the Data Collection Platform (DCP), a partnership between UNITAU and INPE for the Program of Environmental Monitoring of the Rio-Sao Paulo Region. The effluent samples had been placed inside of 20 transparent 2-liter disposable bottles, and than submitted to the following procedures: without exposition to the sun and with 2, 4, 6 and 8 hours of exposition to the sun, four repetitions each, totalizing 20 experiments. The efficiency of the exposition time was determined by the fecal coliform counts in the effluent samples enumerated by the most probable number (MPN) method. It can be observed reduction of fecal coliform counts with the exposition of the effluent to the solar radiation, and this reduction was proportional to the increasing of the exposition time. It was observed an average reduction for fecal coliform counts of 51,2% with 2 hours of solar radiation exposition, and this average reduction increased to 84% with 8 hours of exposition. The results showed that the solarization can be used as a method for reduction of pathogenic microorganisms in the domestic effluent.

Please read the abstract in the section, 00front, of this document / Dissertation (MSc)--University of Pretoria, 2001. / Microbiology and Plant Pathology / MSc / unrestricted

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Thesis (M. Tech.(Environmental Health)) -- Central University of Technology Free State, 2005 / In developing countries such as South Africa commercial chicken farmers produce the majority of eggs, approximately 5.8kg of eggs per capita per annum. Despite this, many people, especially in rural and marginal-urban areas, still consume eggs produced by backyard systems. Backyard systems are characterised by fragmented and small-scale production units that require minimal management and chickens are often unhoused or poorly housed. In most cases, eggs from backyard systems are laid in nests in poor hygienic condition. Eggs are a cheap, readily available and a good source of animal protein and are consumed by the majority of the people in the community, including the young, the old and people with HIV/AIDS. With little information available regarding the microbiological quality of eggs produced by backyard chickens in Southern Africa, the risks posed by these eggs to consumers are unknown. In this study the microbiological quality of eggs from randomly selected household near Hennenman keeping backyard chickens was determined. The study was done over three seasons which included the cold-dry (May-July), mild-dry (October- February) and the warm-wet (August-September) seasons. The following organisms were isolated: Salmonella spp., Pseudomonas spp., Staphylococcus spp., Escherichia coli and Total Coliforms. Staphylococcus spp. was further characterised to species level. Most of the species were of human origin, with the exception of only two species, S. hyicus and S. lentus, which have previously been associated with chickens. Furthermore, questionnaires were administered to the backyard chicken keepers to assess their knowledge regarding chicken keeping and nest hygiene, the proper method of egg collection and storage, and the preparation of eggs. The decrease of vitamins and Staphylococcus spp. occurring during different preparation methods (scrambling, frying and boiling) was also determined. The results obtained showed that the eggshells were more contaminated than the egg contents. This had been expected as the eggshell is more in contact with the external environment than the egg contents are. Faecal contaminants (Salmonella spp., Escherichia coli and Total Coliforms) were present in both the eggshell and the egg contents during all seasons and this could be attributed to the infrequent cleaning of chicken nests as ascertained from the questionnaires. From the vitamin analysis it was observed that backyard-produced eggs had lower concentrations of vitamins A and E compared to commercially-produced eggs. When determining the best preparation method, causing the most degradation of Staphylococcus spp., while on the other hand preserving vitamins, it was found that scrambling was the best method, followed by the frying and boiling methods respectively.

Thesis (M.Tech.: Biotechnology)- Dept. of Biotechnology & Food Technology, Durban University of Technology, 2007 xv, 102 leaves / For decades the genus Aspergillus (of fungi) has been classified based on morphological and growth criteria. Members of the Aspergillus section Flavi are economically valuable and methods of differentiating them are thus very important. Several molecular methods have been developed to distinguish these strains. Also, a number of biochemical and genetic studies have been used in order to provide a better means of classification (Lee et al., 2004). Aflatoxins, the most frequently studied mycotoxins, are produced by certain Aspergillus species/strains/isolates of fungi. The aflatoxin biosynthetic pathway studies have led to a number of discoveries. Several structural and regulatory genes (and their enzymes) involved in the biosynthesis of aflatoxins have been discovered and purified (Trail et al., 1995). Aflatoxin production and contamination of agricultural crops are major causes of economic losses in agriculture. Thus, better methods of characterization/differentiation are required for both aflatoxigenic and non-aflatoxigenic isolates. Molecular biology is one of the current tools used to differentiate between these isolates. Polymerase Chain Reaction (PCR)-based randomly amplified polymorphic DNA (RAPD) analysis has been used successfully in the analysis of DNA relatedness of species of fungi, bacteria, plants and animals. Dendograms which evaluate/assess the likeness between different isolates has also been used (Martinez et al., 2001). Restriction fragment length polymorphism (RFLP) analysis has been applied to a number of studies to detect differences between fungi and to establish relationships between them. Therefore, the scope of this study was to investigate RAPD analysis (with dendograms) and detection of RFLPs by hybridization as molecular methods that can distinctly differentiate or characterize the aflatoxigenic and non-aflatoxigenic Aspergillus isolates.

Fecal samples were obtained from guenons in Gombe National Park utilizing noninvasive, opportunistic sampling techniques. Samples were then examined for the presence of gastrointestinal parasites using chlorazol black stain, Lugol’s iodine staining, as well as concentration via fecal flotation with Sheather’s sugar solution. Results were analyzed using SPSS (IBM corp), and compared to other forested regions in Africa to determine whether hybridization influences parasite prevalence of these guenons living in Gombe; and if these guenons differ from similar guenons in other regions of Africa. The null hypothesis was unable to be rejected in all cases; hybridization could not be stated as a contributing factor for differences found in parasitic prevalence rates. Furthermore, no statistical difference was found between Gombe’s guenons, and those living in other regions of Africa in most cases. The author suspects that the abundance of parasitic generalists discovered, small sample size, and opportunistic sampling protocol contribute to these finding. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection

Sampling data of many surface water bodies in Broward County tend to reveal abnormal levels of bacterial concentrations for total coliform, Escherichia coli and Enterococcus. Given the presence of septic systems in geohydrologically sensitive areas throughout the County, several studies (Morin 2005 and Bocca 2007) suggested a correlation in the high bacterial densities and the septic sites. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

A utilização de embalagens biodegradáveis, tais como os filmes e coberturas comestíveis, apresenta-se como alternativa ao uso de recursos não-renováveis como material de embalagem. A incorporação de substâncias antimicrobianas em embalagens tem como objetivo minimizar o problema da contaminação microbiana em alimentos e, entre elas, os óleos essenciais (OE) têm recebido atenção especial por serem substâncias naturais e atenderem à preferência dos consumidores. Porém, a utilização de OE como um agente antimicrobiano natural é limitada por critérios organolépticos, sendo necessário determinar a concentração mínima necessária para inibir o desenvolvimento de microrganismos sem afetar sensorialmente as características do alimento. Assim, os objetivos desta pesquisa foram: desenvolver um filme comestível à base de alginato com incorporação de agentes antimicrobianos naturais e avaliar a adição de diferentes concentrações de cloreto de cálcio (CaCl2) como agente crosslinking na formulação do filme e na etapa complementar de formação do filme; caracterizar o filme frente às propriedades mecânicas e propriedades de barreira; determinar a concentração mínima inibitória (CIM) de óleos essenciais para Pseudomonas spp., Salmonella spp. e Listeria monocytogenes presentes em carne de frango, e verificar a aceitação pelo consumidor, através da análise sensorial (aroma), de pedaços de peito de frango in natura embalado com o filme antimicrobiano O OE de cravo foi o que se apresentou mais eficiente para os microrganismos testados com CIM de 0,2% sendo este o limite mínimo estudado no planejamento experimental para o desenvolvimento do filme antimicrobiano. As variáveis independentes neste planejamento foram: CaCl2 na faixa de concentração de 0,02 a 0,1% e OE cravo na faixa de 0,2 a 1,0%. Valores acima de 0,0316% de CaCl2, independente da concentração de OE estudada, diminuiram a zona de inibição do crescimento microbiano em testes realizados in vitro, possivelmente devido a formação de um gel muito forte que pode ter dificultado a incorporação da emulsão de OE na matriz polimérica dos filmes. Os resultados de permeabilidade ao vapor de água mostraram que a adição de CaCl2 à formulação dos filmes diminuiu a permeabilidade enquanto a adição de OE cravo foi responsável pelo aumento dessa propriedade. Com relação às propriedades mecânicas, tanto a adição de CaCl2 como a de OE cravo à formulação dos filmes aumentou a resistência máxima à tração. Porém, com relação ao alongamento máximo na ruptura, valores menores foram obtidos com a adição de CaCl2, enquanto maiores valores foram encontrados com a adição de OE cravo à formulação dos filmes. A avaliação da atividade antimicrobiana dos filmes em carne de frango foi realizada somente com a formulação que apresentou os maiores valores de zona de inibição in vitro (CaCl2=0,0316% e OE cravo=0,884%). Após 5 dias de armazenagem a 7º C, observou-se que a utilização do filme adicionado de OE de cravo como embalagem primária em amostras de carne de peito de frango promoveu o controle da multiplicação de L. monocytogenes o mesmo não ocorrendo para as populações de Salmonella spp. e Pseudomonas spp. A análise sensorial relacionada ao aroma da carne de peito de frango mostrou que o uso do filme à base de alginato incorporado de OE cravo é viável. Porém, este filme poderá sofrer interferência da matriz alimentar caso esta matriz apresente exsudação. / The use of biodegradable packaging such as edible films and coatings are an alternative to the use of non-recyclable packaging. The incorporation of antimicrobial substances in packaging aims at reducing food microbial contamination among which, essential oils (EO) have received special attention being natural and attending consumer demand. However, the use of EO as a natural antimicrobial agent is limited by organoleptic criteria making it necessary to determine the minimum concentration to inhibit the multiplication of microorganisms without affecting the sensory characteristics of the food. Therefore, the aims of this research were: to develop an alginate based edible film with natural antimicrobial agents, evaluating the addition of different concentrations of calcium chloride as a crosslinking agent in the formulation of the film and in the complementary stage; to characterize the mechanical properties and barrier properties; to determine the minimum inhibitory concentration (MIC) of EO for Pseudomonas spp, Salmonella spp and Listeria monocytogenes found in chicken meat and to verify consumer acceptance of the product through sensorial analysis (aroma). Among the studied EO, the concentration of 0.2% of clove oil was effective in inhibiting the microorganisms tested, this concentration being the minimum limit used in the experimental design for film development. The independent variables studied in this design were calcium chloride in the range of 0.02 to 0.01% and clove EO in the range of 0.2 to 1.0%. Concentrations of CaCl2 above 0.0316%, independent of the EO concentration, reduced the inhibition zone of microbial growth in in vitro tests, possibly due to the formation of a very strong gel which could have made the incorporation of the EO emulsion in the polymeric matrix of the film very difficult. The results of water vapor permeability tests showed that the addition of CaCl2 to the formulation of the films reduced the permeability while the addition of clove EO increased this property. Regarding to mechanical properties, the addition of CaCl2 as well as clove EO to the film formulation increased the values of tensile strength. On the other hand, relating to elongation at the break, smaller values were obtained with the addition of the salt while the addition of EO provided higher values. The evaluation of antimicrobial activity of the films in chicken meat was performed only with the formulation that showed the highest inhibition values presented in vitro (CaCl2=0.0316% and clove EO=0.0884%). After five days of storage at 7° C, it was observed that the use of the film added by clove EO as primary packaging provided the control of L. monocytogenes growth in samples of chicken meat but not of Salmonella spp and Pseudomonas spp. The sensorial analysis - aroma - showed that the use of alginate based film incorporated with clove EO is viable in food. However, when the food matrix presents exudation, it can interfere in this film.

Orientadores: José Roberto Guimarães, Regina Maura Bueno Franco / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-09-11T21:23:29Z (GMT). No. of bitstreams: 1 Fagnani_RegianeAparecidaGuadagnini_D.pdf: 2932805 bytes, checksum: ed51cdda9a4191dd5c1b275767a76ecd (MD5) Previous issue date: 2014 / Resumo: Neste estudo foi avaliada a eficiência do processo de tratamento por lodos ativados e, a eficiência de um processo oxidativo avançado (POA), a peroxidação assistida por radiação ultravioleta (H2O2/UV) na desinfecção do efluente da estação de esgoto (ETE) Samambaia da cidade de Campinas/SP. A avaliação da eficiência da ETE e dos processos foi feita com base na remoção de coliformes totais (CT), Escherichia coli (EC), Clostridium perfringens (CP), cistos de Giardia spp. oocistos de Cryptosporidium spp., ovos e larvas de helmintos e, na redução dos valores de turbidez, cor (aparente e verdadeira) e carbono orgânico dissolvido (COD). Para tanto, 13 amostras de afluente e 18 amostras de efluente foram coletadas. O efluente foi desinfetado utilizando-se doses UV de 125 a 20.700 mW s cm-2 e concentração de peróxido de hidrogênio de 30 a 93 mg L-1. Os processos de fotólise e peroxidação foram também avaliados de forma isolada. Todas as amostras de afluente e efluente apresentaram as bactérias avaliadas, cistos de Giardia spp. e, larvas e/ou ovos de helmintos. Na avaliação das características temporais do afluente da ETE, verificou-se que alguns dos parâmetros avaliados, tiveram considerável aumento ou redução com relação ao observado em outros períodos. No período de maior incidência de chuvas (primavera, no ano de 2012) observou-se o menor valor para COD (43% menor do que os obtidos para as outras épocas do ano) e, maior valor para a turbidez (aumento de 57%). Na primavera e no inverno detectou-se também oocistos de Cryptosporidium spp., com maior concentração no inverno. Ovos de helmintos tiveram sua quantificação mínima detectada no outono. A peroxidação aplicada isoladamente não promoveu a inativação de nenhum dos organismos avaliados e, nem reduziu os valores das variáveis físicas e químicas. O POA promoveu a redução de mais de 80% do valor de cor aparente e verdadeira (p < 0,05). Os processos foto-assistidos (radiação UV e H2O2/UV) alcançaram a maior inativação de CT e EC com a dose de radiação de 177 mW s cm-2, sendo de 5 log para a fotólise e, o limite <1 NMP/100mL para o POA e, promoveram a inativação de 2 log de CP, independente da dose de radiação UV aplicada. Quanto aos cistos de Giardia spp., os processos avaliados não promoveram a sua redução. Porém o processo de UV e POA gerou alterações nos cistos (p < 0,05) sendo que o POA alcançou alterações (de fluorescência e/ou forma) em 100% dos cistos observados quando utilizada a dose de radiação UV de 1.775 mW s cm-2. Nenhum dos processos reduziu ou danificou ovos de helmintos, independentemente da condição experimental avaliada / Abstract: This study evaluates the effectiveness of activated sludge and the performance of advanced oxidation process (AOP), the peroxidation assisted by ultraviolet radiation (H2O2/UV), used for effluent disinfection at Samambaia Wastewater Treatment Plant (Samambaia WWTP) in Campinas/SP. The evaluation of the WWTP and of the disinfection processes¿ efficiency was based on the inactivation and/or the number of organisms (total coliforms (TC), Escherichia coli (EC), Clostridium perfringens (CP), Giardia spp. cysts, Cryptosporidium spp. oocysts, helminth eggs and larvae) and turbidity, color (apparent and true) and dissolved organic carbon (DOC) reduced. For this evaluation, 13 samples of affluent and 18 of effluent were collected. The effluent was disinfected using UV doses 125 to 20,700 mW s cm-2 and hydrogen peroxide concentration of 30 to 93 mg L-1. The photolysis and peroxidation processes were separately evaluated. Each affluent and effluent sample revealed the bacteria, Giardia spp. cysts and helminth eggs and/or larvae. In the evaluation of affluent seasonality it has been found that some parameters considerably increased or reduced when different periods were compared. In the period with higher incidence of rain (spring of 2012), it was observed that the DCO value was lower (43% lower when compared to other periods) and, turbidity value was higher (an increase of 57%). In the spring and winter Cryptosporidium spp. oocysts were detected with higher concentration in the winter. Helminth eggs had lower quantification during the autumn. The isolated peroxidation process did not promote the inactivation and/or reduction of any evaluated organism, nor reduced the value of any physical or chemical parameter. The AOP promoted the reduction of 80% or higher of apparent and true color (p < 0.05). The photo-assisted processes (UV radiation and AOP) achieved greater inactivation of TC and EC bacteria with UV dose of 177 mW s cm-2, being 5 log of UV radiation and, <1 MPN/100mL of AOP and, promoted the CP inactivation of 2 log, independent on the UV dose applied. The evaluated processes did not promote the Giardia spp. cysts reduction. However UV and AOP processes caused cysts alteration (p < 0.05), as AOP reached 100% cysts alteration when a 1,775 mW s cm-2 UV dose was applied. Helminth eggs were not reduced or damaged for any studied process, independent on the evaluated experimental condition / Doutorado / Saneamento e Ambiente / Doutora em Engenharia Civil