Introduktion: Förlust av tänder är idag vanligt förekommande och kan behandlas med hjälp av dentala implantat. För att installation av implantat ska vara möjlig, krävs tillräcklig benvolym där implantat ska installeras. När det föreligger bendefekter i anslutning till det lokala området för implantatinstallationen utgör simultaneous augmentation technique eller enstegsteknik ett behandlingsalternativ för bentransplantat. För att minimera kontamination med orala bakterier av det uppsamlade benet under beninsamlingsmetoder, används idag preoperativ sköljning med klorhexidin som ett steg i behandlingen.Syftet med denna studie är att undersöka möjligheten till ytterligare minimering av bakteriell kontamination vid implantatinstallation, med hjälp borstning av munhålan med klorhexidingel.Metod: 30 patienter deltog i en dubbelblindad, randomiserad studie där 15 patienter utgjorde en kontrollgrupp och 15 andra patienter fick genomgå den införda preoperativa tilläggsåtgärden. Ben- och paperpoint prov togs från samtliga patienter för bakteriell odling. Antalet kontaminerande bakterier uttrycktes som kolonibildande enheter (CFU/ml). En statistisk analys gjordes för att beräkna bakterieantal och kontaminationsgraden i respektive prov. Resultat: Medelvärdet för antal bakterier i benproven från samtliga patienter i kontrollgruppen beräknades till 8 126 CFU/ml respektive 2 946 CFU/ml i testgruppen dock var skillnaden inte signifikant (P = 0,357).Konklusion: Resultatet i denna studie visar ingen statistisk signifikant skillnad mellan patienter som erhållit den preoperativa profylaktiska tilläggsåtgärden, borstning med klorhexidingel, och patienter som inte erhållit detta hygiensupplement. Dessutom kunde ingen slutsats dras gällande effekten av denna tilläggsmetod på virulenta bakteriearterna P. gingivalis, P. Intermedia och A. actinomycetemcomitans. Ett större patientunderlag krävs i framtida randomiserade kontrollerade studier för att utvärdera denna metods effekt. / Introduction: Missing teeth can be replaced by dental implants. To achieve good results using dental implants, it is important that there is sufficient bone volume. In cases with bone defects, simultaneous augmentation technique becomes an alternative for bone augmentation. To minimize the contamination with oral bacteria during the bone collection, preoperative rinsing with chlorhexidine is today commonly used as a step in the treatment.The aim of this study is to examine the additional effect of preoperative brushing with chlorhexidine gel on avoiding bacterial contamination during the installation of dental implants.Method: 30 patients participated in a randomized, double blinded study. 15 patients were included in the control group and 15 patients underwent an additional step in the treatment with a preoperative brushing with chlorhexidine gel. Bone samples and paperpoint samples were collected and analyzed in a laboratory and a statistic analysis was performed to compare the number of bacterial colonies in samples from the two groups (CFU/ml) present and the degree of contamination.Results: The mean bacterial count in bone samples from all patients in the control group was calculated at 8 126 CFU/ml and 2 946 CFU/ml in the test group. CFU/ml was different between the groups (P = 0.357) but the difference was not significant (P <0.05).Conclusion: Brushing with chlorhexidine gel preoperatively showed no significant effects in the bacterial contamination of bone chips. No recommendation for adding this additional step in the standard treatment with dental implants can therefore be made today.

Bacterial contamination of food is a global concern. Methods of treating bacterial contamination are limited. Bacteriophages, bacterial viruses, offer a promising solution. However, bacteriophages may have limited application for foods that undergo sterilization processing, are inhospitable to organisms, or must be maintained in a dry state. This thesis focused on methods to expand the application of bacteriophages. First, bacteriophages were subjected to generalized stresses of desiccation, heat, and acidity, under laboratory conditions to propagate new populations with improved stress resistance. However, testing of these stress-resistant populations under real-world conditions failed to produce results comparable to generalized laboratory conditions. Success in the application of selected bacteriophages may require high situational specificity during selection, including in terms of food matrix and stress mechanics. The focus of our research shifted from the modification of bacteriophage populations themselves to the development of food-safe protective matrices. Designed matrices encapsulate bacteriophage for integration with modern food production and even the food products themselves. A pullulan-trehalose sugar powder was developed for the protection of a model bacteriophage from pasteurization. Microparticles were engineered such that the majority of the particle would be composed of trehalose as a stabilizer and polysaccharide pullulan was designed to accumulate at the particle surface to slow dissolution. This structure resulted in a bacteriophage powder that remained intact and protective over short-term high-temperature pasteurization, whereas unprotected bacteriophage experienced significant loss in titer. Leucine-lactose and leucine-lactose-maltodextrin microparticles were engineered for the inclusion of bacteriophage in powdered infant formula. The bacteriophage powder was designed as a dormant protection system that could activate upon reconstitution. The excipient system was formulated to not significantly affect the pH, composition, and dissolution of commercial infant formula. The bacteriophage powder was also engineered to match the shelf life and secondary shelf life of infant formula. Altogether, this thesis demonstrates that bacteriophage application in different foods can be expanded through particle engineering. / Thesis / Doctor of Philosophy (PhD) / Bacterial contamination of food can lead to widespread outbreaks and subsequent preventable deaths. Our best tool against bacteria, antibiotics, cannot be widely applied to food for risk to the natural human biome and creation of resistant bacteria. Bacteriophages, viruses that infect bacteria, are a naturally occurring bactericide that offer an alternative solution. This thesis focuses on improving the application of bacteriophages in food. First, bacteriophages are selected for resistance to common food processing stresses, such as heat, drying, and acidity, to prepare future generations that are stress-resistant. Second, a protective sugar powder was designed that could be used to add bacteriophages to milk before pasteurization. Post-pasteurization, the sugar would dissolve and release bacteriophage into the milk to deal with any post-processing contamination. Lastly, an infant-safe bacteriophage powder was developed that could be intermixed with powdered infant formula in an effort to reduce infant death due to the ingestion of bacteria.

Orientador: Cecília Laluce / Resumo: A contaminação bacteriana nas destilarias de etanol é um problema crônico que afeta o rendimento, na medida em que esses microrganismos competem pelo substrato a ser convertido em álcool pelas leveduras e liberam produtos indesejados no meio. A adição de ácido sulfúrico ao inóculo é a prática mais utilizada no controle dessas bactérias, contudo é uma substância de baixa eficácia, que também afeta a levedura. Antibacterianos utilizados complementarmente devem levar em conta a seletividade; o espectro de ação; e ainda restrições em fermentações que utilizam o excedente de levedura para ração animal. Nesse contexto, esse trabalho se propôs a estudar diversos biocidas, com base na literatura e desempenho em outras áreas. Foram realizadas fermentações por bateladas em frascos agitados em condições operacionais padrão (pH, temperatura, concentração de açúcares) com recuperação de células ao final de cada ciclo, reproduzindo o processo industrial. Os inóculos contendo leveduras e bactérias foram tratados com os seguintes produtos: peróxido de hidrogênio aditivado com prata; cloro oxigenado; triclorocarbanilida; cloreto de benzalcônio; digluconato de clorexidina; maitenina; salinomicina, e agentes quelantes EDTA e HEDTA, além dos produtos referência (beta ácido de lúpulo e monensina). Ao final das fermentações foram analisadas a população de bactérias, a viabilidade da levedura, e os teores de ácido lático e etanol. O biocida a base de peróxido, na dose 1.000 ppm não mostrou a mesma ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Bacterial contamination in ethanol distilleries is a chronic problem that affecting the yield, once these microorganisms compete for the substrate to be converted to alcohol by yeast, as well as release undesired products in the medium. The addition of sulfuric acid to the inoculum is the most used practice to control such bacteria, but is a substance of low efficacy, which also affects the yeast. Antibacterial used in addition should take into account the selectivity; spectrum; and also restriction in fermentation that uses yeast surplus for animal feed. In this context, this work proposes to study various biocides, based on the literature and performance in other areas. Batch fermentations were performed in shake flasks under standard operational conditions (pH, temperature, sugar concentration) with a recovery of cells at the end of each cycle, reproducing the industrial process. The inoculum containing yeast and bacteria were treated with hydrogen peroxide plus silver; oxygenated chlorine; trichlorocarbanilide plus benzalkonium chloride; chlorhexidine digluconate; maytenin; salinomycin, and chelating agents EDTA and HEDTA, indeed the reference products (beta hops acid and monensin). At the end of fermentations were performed analysis of population of bacteria, yeast viability and lactic acid and ethanol concentration. The peroxide-based biocide in the dose 1000 ppm did not showed the same efficacy recorded in preliminary tests in vitro, which showed a MIC of 200 ppm for l... (Complete abstract click electronic access below) / Doutor

O gênero Heliconia tem participação crescente na floricultura tropical, sendo utilizada principalmente como flor de corte e para o paisagismo. A aplicação da micropropagação na produção de helicônias pode atuar na otimização da produtividade e na melhoria da qualidade do produto, proporcionando a multiplicação rápida e em grande escala das mudas, independentemente do período do ano, a multiplicação de híbridos e matrizes de grandes potenciais, a produção mais uniforme e redução do período até a colheita. Entretanto, o sucesso do processo de micropropagação depende de vários fatores, entre eles, o estabelecimento do explante in vitro, a adequação do meio de cultura e a escolha do melhor substrato na fase de aclimatação, como estudadas no presente trabalho. Uma das maiores dificuldades enfrentadas no estabelecimento in vitro dos explantes de helicônias é a contaminação bacteriana. De acordo com os resultados obtidos, as cultivares Heliconia bihai cv. Peach Pink, H. ortotricha Candy Cane e H. ortotricha L. Anderss cv. Total Eclipse respondem diferentemente aos tratamentos de assepsia testados. A utilização do meio MS (Murashige; Skoog, 1962), com a concentração normal dos sais MS, 2,5 mg/ L BAP e 0,10 mg/L ANA foi o meio de cultura mais adequado para o cultivo in vitro de H. ortrotricha cv. Candy Cane, proporcionando uma boa taxa de brotação por explante e plantas bem desenvolvidas. Durante a aclimatação das plantas de H. ortotricha Candy Cane, as misturas de Plant Max® Horticultura + Fibra de coco e Plant Max® Horticultura + Casca de arroz carbonizado foram superiores em relação aos outros substratos testados, tanto pelo maior índice de plantas sobreviventes, quanto pelo maior crescimento da parte aérea, apresentando uma boa coloração das folhas e um maior desenvolvimento do sistema radicular. Para identificação dos contaminantes, 100 isolados de bactérias foram obtidos de meios de cultura contaminados e das folhas das plantas de casa de vegetação e submetidos a análises moleculares para a caracterização por Análise de Restrição de DNA Ribossomal Amplificado (ARDRA) e identificação pelo sequenciamento parcial do gene 16S rRNA. As bactérias isoladas das folhas de helicônia em meios de cultura TSA e R2A foram somente quatro gêneros nas três cultivares, identificados como Arthrobacter sp., Xanthomonas sp., Burkholderia sp. e Rhizobium sp.. Em meio de cultura contaminado constatou-se a presença de Burkholderia sp. nas culturas de H. ortotricha Candy Cane e H. ortotricha L. Anderss. cv. Total Eclipse e de Burkholderia sp. e Rhizobium em H. bihai cv. Peach Pink. As bactérias contaminantes durante o estabelecimento in vitro dos explantes de helicônias podem ser, portanto, provenientes das comunidades endofíticas da planta matriz fornecedora do explante / The Heliconia genus has increasing participation in the tropical floriculture, used mainly as cut flower and for landscape. The use of micropropagation in the process of heliconia production can improve product quality and productivity, providing large-scale and efficient plant multiplication, independently of the season, clonal multiplication of hybrids and other valuable plants, consequently with a more uniform production and possibility of a shorter period for harvesting. However, the success of the micropropagation process depends on various factors, such as the explant establishment in vitro, culture medium and a suitable substrate for acclimatization, which were studied in this work. Bacterial contamination is one of the difficulties for the in vitro establishment of heliconia explants. The results showed that Heliconia bihai cv. Peach Pink, H. ortotricha Candy Cane and H. ortotricha L. Anderss. cv. Total Eclipse responded differently to the descontamination treatments used. The use of full strength of MS (Murashige; Skoog, 1962) medium supplemented with 2,5 mg/L BAP and 0,10 mg/L ANA was the best for the in vitro culture of H. ortrotricha cv. Candy Cane, providing good multiplication rates, with well developed plants. H. ortotricha Candy Cane acclimatization showed better results in substrate mixtures containing Plant Max® Horticulture + Coconut fiber and Plant Max® Horticulture + Rind of carbonized rice with better rates of survival, better development of the aerial parts and root system development. For identification of the contaminantes, 100 bacteria isolates were obtained from contaminated culture media and leaves of greenhouse plants and submitted to morphological and molecular analyses to characterization for Amplified Ribosomal DNA Restriction Analysis (ARDRA) and identification for partial 16S rRNA gene sequencing. The bacterial isolates obtained from the leaves in TSA and R2A culture media had been only four species in the three heliconia cultivars, and were identified as Arthrobacter sp., Xanthomonas sp., Burkholderia sp. and Rhizobium sp.. In culture media contaminated Burkholderia sp. was evidenced in cultures of H. ortotricha Candy Cane and H. ortotricha L. Anderss. cv. Total Eclipse and Burkholderia sp. and Rhizobium sp. in H. bihai cv. Peach Pink. The bacterial contaminants observed during the in vitro establishment of heliconia explants originated from the endophytic community of the plants which were used as explant sources

Made available in DSpace on 2014-06-11T19:27:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-14Bitstream added on 2014-06-13T20:35:32Z : No. of bitstreams: 1 santos_ss_me_jabo.pdf: 560994 bytes, checksum: b6007a23b1c54664298b50a409bb2bc6 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O leite é um alimento altamente nutritivo e excelente substrato para a multiplicação de microrganismos. Os estafilococos estão entre os principais contaminantes do leite, seja em decorrência da mastite ou de falhas de higienização. A contaminação do leite pode favorecer a adesão bacteriana sobre superfícies com a formação de biofilmes, cujos fragmentos podem se desprender e contaminar o produto durante o processo de beneficiamento, o que representa um risco à saúde do consumidor. Tendo isto em foco, objetivou-se o presente estudo, em uma micro-usina do Estado de São Paulo, a fim de investigar a presença e formação de biofilme por Staphylococcus spp, antes e após o processo de higienização. Colheu-se o total de 60 amostras por meio de suabes, antes e após o processo de higienização, das superfícies do tanque de recepção, do tanque de estocagem de leite cru, da tubulação de saída do pasteurizador, do tanque de estocagem de leite pasteurizado, e da tubulação da máquina de envase. Foram colhidas, ainda, amostras de leite no tanque de recepção, no tanque de estocagem de leite cru, na tubulação de saída do pasteurizador e amostras de leite envasado, assim como das embalagens plásticas vedadas e vazias, utilizadas para o envase do leite pasteurizado. Dentre 41 estirpes de Staphylococcus spp isoladas, 16 (39,0%) mostraram-se positivas na prova da coagulase, enquanto que 25 (61,0%) foram negativas. Por meio de análise genotípica, com a técnica de Reação em Cadeia da Polimerase (PCR), pode-se observar que, dentre as 16 estirpes coagulase positivas, quatro (25%) apresentavam o gene icaA e 16 (100%) possuíam o gene icaD. Dentre as 25 estirpes coagulase negativas, 11 (44%) possuíam o gene icaA e 25 (100%) possuíam o gene icaD. Visualizou-se, por meio da microscopia eletrônica de varredura... / Milk is a highly nutritious food and excellent substrate for the multiplication of microorganisms. Staphylococci are one of the major contaminants of milk whether due to mastitis or hygiene failures in cleaning. Milk contamination may encourage bacterial adherence on surfaces with the formation of biofilms, whose fragments can detach and contaminate the product during beneficial processing, which represents a health risk to the consumers. With this in focus as the objective of this present study, to investigate the presence and formation of biofilm of Staphylococcus spp before and after the cleaning process in a micro-dairy plant in São Paulo State. A total of 60 swab samples were collected before and after the cleaning process from the reception tank surfaces, the raw milk storage tank storage, the pasteurizer outlet pipe, the pasteurized milk storage tank, and the filling machine. Further samples were collected of the milk in the receiving tank, the raw milk storage tank, from the pasteurizer outlet pipe, and packaged milk, as well as the empty sealed plastic packaging used for packaging the pasteurized milk. Of the 41 strains of isolated Staphylococcus spp, 16 (39.0%) indicated positive in the coagulase test, while 25 (61.0%) were negative. Through genetic analysis, using the Polymerase Chain Reaction (PCR) technique, it was observed that within the 16 strains of coagulase-positive, four (25%) presented the gene icaA and 16 (100%) had the gene icaD. Of the 25 strains of coagulase-negative, 11 (44%) had the gene icaA and 25 (100%) had the gene icaD. It was seen using a scanning electron microscope the start of bacteria adhesion and the formation of biofilm for all the isolated strains. From the obtained results it was possible to see evidence to the potential risk to the health of the consumer represented... (Complete abstract click electronic access below)

O gênero Heliconia tem participação crescente na floricultura tropical, sendo utilizada principalmente como flor de corte e para o paisagismo. A aplicação da micropropagação na produção de helicônias pode atuar na otimização da produtividade e na melhoria da qualidade do produto, proporcionando a multiplicação rápida e em grande escala das mudas, independentemente do período do ano, a multiplicação de híbridos e matrizes de grandes potenciais, a produção mais uniforme e redução do período até a colheita. Entretanto, o sucesso do processo de micropropagação depende de vários fatores, entre eles, o estabelecimento do explante in vitro, a adequação do meio de cultura e a escolha do melhor substrato na fase de aclimatação, como estudadas no presente trabalho. Uma das maiores dificuldades enfrentadas no estabelecimento in vitro dos explantes de helicônias é a contaminação bacteriana. De acordo com os resultados obtidos, as cultivares Heliconia bihai cv. Peach Pink, H. ortotricha Candy Cane e H. ortotricha L. Anderss cv. Total Eclipse respondem diferentemente aos tratamentos de assepsia testados. A utilização do meio MS (Murashige; Skoog, 1962), com a concentração normal dos sais MS, 2,5 mg/ L BAP e 0,10 mg/L ANA foi o meio de cultura mais adequado para o cultivo in vitro de H. ortrotricha cv. Candy Cane, proporcionando uma boa taxa de brotação por explante e plantas bem desenvolvidas. Durante a aclimatação das plantas de H. ortotricha Candy Cane, as misturas de Plant Max® Horticultura + Fibra de coco e Plant Max® Horticultura + Casca de arroz carbonizado foram superiores em relação aos outros substratos testados, tanto pelo maior índice de plantas sobreviventes, quanto pelo maior crescimento da parte aérea, apresentando uma boa coloração das folhas e um maior desenvolvimento do sistema radicular. Para identificação dos contaminantes, 100 isolados de bactérias foram obtidos de meios de cultura contaminados e das folhas das plantas de casa de vegetação e submetidos a análises moleculares para a caracterização por Análise de Restrição de DNA Ribossomal Amplificado (ARDRA) e identificação pelo sequenciamento parcial do gene 16S rRNA. As bactérias isoladas das folhas de helicônia em meios de cultura TSA e R2A foram somente quatro gêneros nas três cultivares, identificados como Arthrobacter sp., Xanthomonas sp., Burkholderia sp. e Rhizobium sp.. Em meio de cultura contaminado constatou-se a presença de Burkholderia sp. nas culturas de H. ortotricha Candy Cane e H. ortotricha L. Anderss. cv. Total Eclipse e de Burkholderia sp. e Rhizobium em H. bihai cv. Peach Pink. As bactérias contaminantes durante o estabelecimento in vitro dos explantes de helicônias podem ser, portanto, provenientes das comunidades endofíticas da planta matriz fornecedora do explante / The Heliconia genus has increasing participation in the tropical floriculture, used mainly as cut flower and for landscape. The use of micropropagation in the process of heliconia production can improve product quality and productivity, providing large-scale and efficient plant multiplication, independently of the season, clonal multiplication of hybrids and other valuable plants, consequently with a more uniform production and possibility of a shorter period for harvesting. However, the success of the micropropagation process depends on various factors, such as the explant establishment in vitro, culture medium and a suitable substrate for acclimatization, which were studied in this work. Bacterial contamination is one of the difficulties for the in vitro establishment of heliconia explants. The results showed that Heliconia bihai cv. Peach Pink, H. ortotricha Candy Cane and H. ortotricha L. Anderss. cv. Total Eclipse responded differently to the descontamination treatments used. The use of full strength of MS (Murashige; Skoog, 1962) medium supplemented with 2,5 mg/L BAP and 0,10 mg/L ANA was the best for the in vitro culture of H. ortrotricha cv. Candy Cane, providing good multiplication rates, with well developed plants. H. ortotricha Candy Cane acclimatization showed better results in substrate mixtures containing Plant Max® Horticulture + Coconut fiber and Plant Max® Horticulture + Rind of carbonized rice with better rates of survival, better development of the aerial parts and root system development. For identification of the contaminantes, 100 bacteria isolates were obtained from contaminated culture media and leaves of greenhouse plants and submitted to morphological and molecular analyses to characterization for Amplified Ribosomal DNA Restriction Analysis (ARDRA) and identification for partial 16S rRNA gene sequencing. The bacterial isolates obtained from the leaves in TSA and R2A culture media had been only four species in the three heliconia cultivars, and were identified as Arthrobacter sp., Xanthomonas sp., Burkholderia sp. and Rhizobium sp.. In culture media contaminated Burkholderia sp. was evidenced in cultures of H. ortotricha Candy Cane and H. ortotricha L. Anderss. cv. Total Eclipse and Burkholderia sp. and Rhizobium sp. in H. bihai cv. Peach Pink. The bacterial contaminants observed during the in vitro establishment of heliconia explants originated from the endophytic community of the plants which were used as explant sources

Made available in DSpace on 2014-07-29T15:13:49Z (GMT). No. of bitstreams: 1 tese Maria Luiza Stringhini.pdf: 1950735 bytes, checksum: 3968be9688ed5eaf09c6664365da77c0 (MD5) Previous issue date: 2008-12-05 / This study was developed in order to study the behavior of Pseudomonas aeruginosa inoculated on shell of washed and unwashed eggs. It was evaluated the socioeconomic and microbiological profiles of hands, nasal cavity and oropharynx of 32 volunteers staff from four commercial poultry farms located in the metropolitan region of Goiânia-GO. It was found that 56% of the workers are males and that the most common age group (47%) is between 18 and 23 years. Approximately 41% (13/32) had 6th to 9th grade of elementary school and 44% had monthly family income between two and three minimum salaries. Most microorganisms isolated and identified among the workers belong to the natural microflora of them. However, Escherichia coli was isolated from the hands of 12.5% individuals before starting day of work indicating contamination of fecal origin. Deteriorated microorganisms for eggs also were identified in the handlers as Pseudomonas spp. and Enterobacter spp. Among the Gram-positive bacteria identified detached Staphylococcus coagulase positive that can pose dangers to health of consumers. After this initial research, it was evaluated the bacteriological quality of 576 washed and 132 unwashed eggs of Dekalb White hens obtained in four commercial poultry farms located in the metropolitan area of Goiânia, collected half in the classification hall, and the other half, in the facilities. Counts of mesophilic and positive Staphylococcus coagulase and Most Probable Number (MPN) of total and fecal coliforms in shells and internal content of eggs and Salmonella spp. research in eggshells were made. It was concluded that washed eggs from commercial egg farms had better eggshell bacteriological quality than unwashed eggs but the washing process adopted must be made appropriate in order to avoid contamination. In the following experiment aimed to verify the quality of commercial unwashed eggs submitted to experimental contamination by Pseudomonas aeruginosa. Were contaminated, by handling, with 3.0 x 102 and 6.0 x 105 colony-forming units (CFUs) of Pseudomonas aeruginosa/mL of solution, 576 unwashed eggs without cracks, classified as large, laying hens with 30 to 40 weeks of age. After contamination, the eggs were stored at 5oC and 28oC for 30 days. Every 10 days were carried out analyses of physical quality of eggs (weight of the egg, specific gravity, shell thickness, percentage of yolk, albumen and shell, Haugh unit, rates of yolk and albumen) and pH and counting of the contaminated bacteria in shell and contents of the eggs. During storage, there was control of bacterial multiplication in the shell of the eggs kept at 5oC (p<0,05). However, in content, the cooling controlled the growth of bacteria only in eggs contaminated with initial higher inoculum. It was concluded that the cooling maintains the internal quality of the eggs, even when contaminated and also retains the hygienic-sanitary characteristics of the product. In the last experiment aimed to check the quality of commercial washed eggs inoculated in the shell with Pseudomonas aeruginosa, stored at 5oC and 25oC. It was used 576 eggs, without cracks, classified as large, from laying hens with 30 to 40 weeks of age, line Dekalb White. The experimental design was completely randomized in a 3 x 2 factorial (contamination and temperature storage) with 12 repetitions for physical quality and pH and four repetitions for microbiological variables. The eggs were contaminated by handling, with 7.8 x 102 and 6.0 x 105 colony-forming units (CFUs) of Pseudomonas aeruginosa/mL of solution and stored at 5oC and 25oC for 30 days. Every ten days it was carried out analyses of physical quality of eggs, similar to the previous experiment, pH and counts of Pseudomonas aeruginosa in shell and contents of the eggs. The eggs stored at 5oC showed better internal quality (p<0,05) and lower bacterial counts in shell and contents of the eggs (p<0,05) regardless of the initial concentration of inoculum. It was concluded that the cooling provides better internal quality, physical, chemical and bacteriological of eggs, during 30 days of storage. / O presente estudo foi desenvolvido com o intuito de estudar o comportamento de Pseudomonas aeruginosa inoculadas na casca de ovos lavados e não lavados. Foram determinados os perfis socioeconômico e microbiológico de mãos, cavidade nasal e orofaringe de 32 funcionários de quatro granjas de postura comercial da região metropolitana de Goiânia-GO. Verificou-se que 56% dos funcionários pertenciam ao gênero masculino e que a faixa etária mais frequente estava entre 18 e 23 anos. Treze dentre 32 indivíduos (41%) possuíam do 6º ao 9º ano do ensino fundamental e 44% tinham renda mensal familiar entre dois e três salários mínimos. A maioria dos microrganismos isolados e identificados entre os operários pertence à microbiota natural do homem. Entretanto, Escherichia coli foi encontrada nas mãos de 12,5% dos funcionários, antes de iniciar jornada de trabalho, indicando contaminação fecal. Também foram isoladas, das mãos dos trabalhadores, bactérias deteriorantes para os ovos como Pseudomonas spp. e Enterobacter spp. Dentre as bactérias Gram-positivas, destacou-se Staphylococcus coagulase positivo, que pode representar perigo à saúde do consumidor. Após essa investigação inicial, foi avaliada a qualidade bacteriológica de 576 ovos lavados e 132 ovos não lavados da linhagem Dekalb White obtidos em quatro granjas de postura comercial da região metropolitana de Goiânia-GO, sendo a metade coletada na sala de classificação e, a outra metade, nos galpões. Foram realizadas contagens de mesófilos e Staphylococcus coagulase positivo e Número Mais Provável de coliformes totais e fecais nas cascas e conteúdos e pesquisa de Salmonella spp. nas cascas. Concluiu-se que ovos lavados possuem melhor qualidade bacteriológica de casca do que ovos não-lavados, entretanto, o procedimento de lavagem deve ser realizado de forma adequada a fim de se evitar contaminação. No experimento seguinte objetivou-se verificar a influência da contaminação experimental na casca de ovos não-lavados com Pseudomonas aeruginosa. Foram contaminados, pelo manuseio, com inóculos de 3 x 102 e 6 x 105 unidades formadoras de colônias (UFCs) de Pseudomonas aeruginosa/mL de solução, 576 ovos grandes, sem trincas de poedeiras leves, com 30 a 40 semanas de idade. Após contaminação, os ovos foram armazenados a 5ºC e a 28ºC por 30 dias. A cada dez dias foram realizadas análises de qualidade física dos ovos (peso, gravidade específica, espessura de casca, porcentagem de gema, albume e casca, unidade Haugh, índices de gema e albume), pH e contagens da bactéria contaminante na casca e conteúdo dos ovos. Durante o armazenamento, houve controle da multiplicação bacteriana nas cascas dos ovos contaminados e mantidos a 5ºC (p<0,05). No entanto, no conteúdo, a refrigeração controlou o crescimento da bactéria apenas de ovos contaminados com maior inóculo. Pode-se concluir que a refrigeração mantém a qualidade interna dos ovos, mesmo quando contaminados e que também conserva as características higiênico-sanitárias do produto. No último experimento, objetivouse verificar a influência da contaminação experimental com Pseudomonas aeruginosa na qualidade física de ovos lavados e armazenados a 5ºC e 25ºC. Foram utilizados 576 ovos, sem trincas, classificados como grandes, de poedeiras leves com 30 a 40 semanas de idade, da linhagem Dekalb White. O delineamento empregado foi inteiramente casualizado em esquema fatorial 3 x 2 (contaminação e temperatura de armazenamento) com 12 repetições para variáveis de qualidade física e pH e quatro repetições para variáveis microbiológicas. Os ovos foram contaminados, pelo manuseio, com 7,8 x 102 e 6 x 105 UFCs de Pseudomonas aeruginosa/mL de solução e armazenados a 5oC e 25oC por 30 dias. A cada dez dias foram realizadas análises de qualidade física dos ovos, semelhantes ao experimento anterior, pH e contagens de Pseudomonas aeruginosa na casca e conteúdo dos ovos. Os ovos armazenados a 5ºC apresentaram melhores valores (p<0,05) de qualidade interna e menor contagem bacteriana na casca e no conteúdo (p<0,05), independentemente da concentração inicial do inóculo. Concluiu-se que a refrigeração proporciona melhor quallidade interna, física, química e bacteriológica de ovos, durante 30 dias de armazenamento.

A study was carried out at Poultry Science Laboratory LAVIC at the Federal University of Santa Maria UFSM. The aim was avaluated the effect of different feeding schedules on the performance and eggs quality of broilers breeders Cobb 500. The experimental period was separated into two phases, the first from 28th to 40th week (Phase I) and the second from 40th to 60th week (Phase II) of hen s age. The feeding schedules evaluated were: a single feeding at 08:00 am; twice daily feeding (50% at 08:00 am and 50% at 3:00 pm) and a single feeding at 3:00 pm. At the Phase I, was used 546 females and 63 males allocated in a completely randomized design (CRD) with 7 pens with 26 females and 3 males per repetition and, to the Phase II was used 330 females and 45 males assigned in a CRD with 5 pens with 22 females and 3 males by repetition. The diets were based on corn and soybean meal. At the Phase I, the egg production of hens fed at 3 pm was reduced (P=0.0002). These hens had higher egg and yolk weight than hens fed at 8 am. Hens fed at 3 pm showed better shell quality (egg specific gravity, weight and thickness). The bacterial contamination of the shell was not affected by the diffirent feeding schedules, as well as hatchability, fertility, contaminated and pipped eggs. Embryonic mortality was the lowest in eggs came from hens fed at 8 am. The hatchability of fertile shown to be higher in hens fed once daily in the morning than broiler breeders fed twice daily. At the Phase II, the egg production was not affected by feeding schedules. The hens fed in the afternoon had higher egg and shell weight tham others. The hens fed at 3 pm had higher egg specific gravity and eggshell thickness than eggs come from hens fed at 8 am. Calcium (Ca) and phosphorus (P) plasma levels (21 hours after laying) were higher in hens fed at 3 pm than hens fed at 8 am. The tibia weight was higher in hens fed 8 am than hens fed twice daily feeding. A single feeding at 3:00 pm showed lowest egg production of the 28th to 40th weeks of age. Broiler breeders fed in the afternoon had better egg quality and bacteriological differences were not found in the eggs of hens fed at different schedules. / Um estudo foi conduzido no Laboratório de Avicultura LAVIC da Universidade Federal de Santa Maria (UFSM) com o objetivo de avaliar o efeito de diferentes horários de arraçoamento sobre o desempenho e qualidade de ovos de matrizes de frangos de corte da linhagem Cobb 500. O período experimental foi dividido em duas fases, a primeira da 28ª a 40ª semanas (Fase I) e a segunda da 40ª a 60ª semanas (Fase II) de idade das aves. Avaliaram-se três horários de arraçoamento: único - 8hs; duas vezes ao dia (50% às 8hs e 50% às 15hs) e único - 15hs. Na Fase I foram utilizadas 546 fêmeas e 63 machos distribuídos em um deliamento inteiramente casualizado (DIC) composto por 7 repetições de 26 fêmeas e 3 machos. Na Fase II utilizou-se 330 fêmeas e 45 machos distribuídos em um DIC composto por 5 repetições de 22 fêmeas e 3 machos. As dietas foram à base de milho e farelo de soja. Na Fase I, a taxa de postura de aves alimentadas às 15hs foi reduzida (P=0.0002). Estas aves apresentaram maior peso de ovo e gema em comparação às aves alimentadas às 8hs e, aves alimentadas às 15hs apresentaram melhor qualidade de casca (gravidade específica, peso e espessura) em relação às demais. A contaminação bacteriológica da casca não foi afetada pelos diferentes horários de arraçoamento, bem como eclodibilidade, fertilidade, ovos contaminados e bicados. A mortalidade embrionária foi menor em ovos resultantes de matrizes arraçoadas às 8hs. Estas aves produziram ovos que apresentaram maior taxa de eclodibilidade de ovos férteis em relação às aves alimentadas duas vezes ao dia. Na Fase II, a taxa de postura não foi afetada pelos horários de arraçoamento. Matrizes alimentadas à tarde apresentaram maior peso de ovo e casca em relação às demais. Estas aves apresentaram maior gravidade específica e espessura de casca em relação às aves alimentadas às 8hs. Cálcio (Ca) e fósforo (P) plasmáticos (21 horas após a postura) foram maiores em matrizes arraçoadas às 15hs em relação às aves alimentadas apenas às 8hs. Matrizes alimentadas às 8hs apresentaram maior peso de tíbia do que aquelas alimentadas duas vezes ao dia. O arraçoamento único às 15hs demonstrou menor produção de ovos da 28ª a 40ª semanas de idade. Matrizes alimentadas a tarde apresentam melhor qualidade de ovos, sendo que não foram encontradas diferenças bacteriológicas nos ovos das aves alimentadas em diferentes horários.

The consumption of unsafe fresh vegetables has been linked to an increasing number of outbreaks of human infections. In Lebanon, although raw vegetables are major constituents of the national cuisine, studies on the safety of fresh produce are scant. This research employed a holistic approach to identify the different stages of the food chain that contribute to the microbiological risks on fresh produce and the spreading of hazards. A thorough analysis of the institutional and regulatory framework and the socio-political environment showed that the safety of local fresh produce in Lebanon is at risk due to largely unregulated practices and shortfalls in supporting the agricultural environment as influenced by the lack of a political commitment. Microbiological analysis showed that the faecal indicator levels ranged from < 0.7 to 7 log CFU/g (Escherichia coli), 1.69-8.16 log CFU/g (total coliforms) and followed a significantly increasing trend from fields to the post-harvest washing area. At washing areas, Salmonella was detected on lettuce (6.7% of raw vegetables from post-harvest washing areas). This suggested that post-harvest cross-contamination occurs predominantly in the washing stage. At retails, a combination of observation and self-reported data provided an effective tool in assessing knowledge, attitudes and practices. It showed that the food safety knowledge and sanitation practices of food handlers were inadequate, even among the better trained in corporate-managed SMEs. Overall, the microbiological quality of fresh-cut salad vegetables in SMEs was unsatisfactory. The link between Staphylococcus aureus and microorganism levels on fresh salads vegetables and the overall inspection scores could not be established. On the other hand, inspection ratings on individual components, e.g., cleanliness and cross-contamination preventive measures showed significant correlation with Listeria spp. levels. Together, results confirmed that inspection ratings don’t necessary reflect the microbiological safety of fresh vegetables and that the application of control points of risk factors that likely to contribute to microbial contamination in the production environment are essential. The washing methods were limited in their effectiveness to reduce the contamination of parsley with Salmonella. In general, the pre-wash chopping and storing of parsley at 30ºC reduced the decontamination effect of all solutions, including sodium dichloroisocyanurate which was reduced by 1.3 log CFU/g on both intact and chopped leaves stored at 30ºC. In such conditions, the transfer rate of Salmonella from one contaminated parsley to subsequently chopped clean batches on the same cutting board(CB) recorded 60%-64%. Furthermore, the transmission of Salmonella persisted via washed CBs stored at 30°C for 24 h. It is recommended to keep parsley leaves unchopped and stored at 5ºC until wash for an optimum decontamination effect and to apply vigilant sanitation of CBs after use with fresh produce. This research presented important data for quantitative risk assessment for Salmonella in parsley and useful descriptive information to inform decision-makers and educators on microbial hazards associated with fresh produce in Lebanon. It also highlighted the risks areas that require urgent interventions to improve food safety. Considering the complex institutional and political challenges in Lebanon, there is an obvious need to direct development programs and support towards local agriculture production, effective education strategies and growing awareness of consumers and stakeholders on food safety related risks.

Orientador: Antonio Nader Filho / Banca: Angela Cleusa de Fatima Banzatto de Carvalho / Banca: Luiz Francisco Zafalon / Resumo: O leite é um alimento altamente nutritivo e excelente substrato para a multiplicação de microrganismos. Os estafilococos estão entre os principais contaminantes do leite, seja em decorrência da mastite ou de falhas de higienização. A contaminação do leite pode favorecer a adesão bacteriana sobre superfícies com a formação de biofilmes, cujos fragmentos podem se desprender e contaminar o produto durante o processo de beneficiamento, o que representa um risco à saúde do consumidor. Tendo isto em foco, objetivou-se o presente estudo, em uma micro-usina do Estado de São Paulo, a fim de investigar a presença e formação de biofilme por Staphylococcus spp, antes e após o processo de higienização. Colheu-se o total de 60 amostras por meio de suabes, antes e após o processo de higienização, das superfícies do tanque de recepção, do tanque de estocagem de leite cru, da tubulação de saída do pasteurizador, do tanque de estocagem de leite pasteurizado, e da tubulação da máquina de envase. Foram colhidas, ainda, amostras de leite no tanque de recepção, no tanque de estocagem de leite cru, na tubulação de saída do pasteurizador e amostras de leite envasado, assim como das embalagens plásticas vedadas e vazias, utilizadas para o envase do leite pasteurizado. Dentre 41 estirpes de Staphylococcus spp isoladas, 16 (39,0%) mostraram-se positivas na prova da coagulase, enquanto que 25 (61,0%) foram negativas. Por meio de análise genotípica, com a técnica de Reação em Cadeia da Polimerase (PCR), pode-se observar que, dentre as 16 estirpes coagulase positivas, quatro (25%) apresentavam o gene icaA e 16 (100%) possuíam o gene icaD. Dentre as 25 estirpes coagulase negativas, 11 (44%) possuíam o gene icaA e 25 (100%) possuíam o gene icaD. Visualizou-se, por meio da microscopia eletrônica de varredura... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Milk is a highly nutritious food and excellent substrate for the multiplication of microorganisms. Staphylococci are one of the major contaminants of milk whether due to mastitis or hygiene failures in cleaning. Milk contamination may encourage bacterial adherence on surfaces with the formation of biofilms, whose fragments can detach and contaminate the product during beneficial processing, which represents a health risk to the consumers. With this in focus as the objective of this present study, to investigate the presence and formation of biofilm of Staphylococcus spp before and after the cleaning process in a micro-dairy plant in São Paulo State. A total of 60 swab samples were collected before and after the cleaning process from the reception tank surfaces, the raw milk storage tank storage, the pasteurizer outlet pipe, the pasteurized milk storage tank, and the filling machine. Further samples were collected of the milk in the receiving tank, the raw milk storage tank, from the pasteurizer outlet pipe, and packaged milk, as well as the empty sealed plastic packaging used for packaging the pasteurized milk. Of the 41 strains of isolated Staphylococcus spp, 16 (39.0%) indicated positive in the coagulase test, while 25 (61.0%) were negative. Through genetic analysis, using the Polymerase Chain Reaction (PCR) technique, it was observed that within the 16 strains of coagulase-positive, four (25%) presented the gene icaA and 16 (100%) had the gene icaD. Of the 25 strains of coagulase-negative, 11 (44%) had the gene icaA and 25 (100%) had the gene icaD. It was seen using a scanning electron microscope the start of bacteria adhesion and the formation of biofilm for all the isolated strains. From the obtained results it was possible to see evidence to the potential risk to the health of the consumer represented... (Complete abstract click electronic access below) / Mestre