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Desempenho de microbicidas para preservação de peles e courosFontoura, Juliana Tolfo da January 2013 (has links)
Um problema na indústria coureira é a deterioração de peles e couros devido ao desenvolvimento de microrganismos no processamento do couro. As peles e os couros contêm nutrientes adequados para o crescimento de microrganismos, como carboidratos, gorduras e proteínas, além das condições ambientais, alta umidade, temperatura de armazenagem e pH favoráveis. Alguns gêneros de bactérias e fungos sintetizam importantes substâncias deste substrato, causando modificações prejudiciais na superfície do couro e nas propriedades físico-mecânicas, deixando manchas pigmentadas de difícil remoção, afetando a qualidade do produto final e causando perda de valor comercial. Desta forma, surge a necessidade de desenvolver estratégias de controle dos microrganismos de modo a reduzir ou eliminar este problema. Para tanto, recorre-se comumente à utilização de microbicidas. No passado, a ação esperada dos agentes antimicrobianos era principalmente de fornecer uma proteção eficaz, mas em anos mais recentes, a preocupação com a sua toxicidade e com potenciais riscos ecológicos tornou-se também importante. Nos dias atuais uma grande preocupação mundial é o cuidado com a preservação do meio ambiente. Devido a isto, várias pesquisas estão voltadas para o desenvolvimento de novas tecnologias limpas e renováveis como também a otimização de processos. Tendo em vista a melhoria de processos no que diz respeito ao uso de microbicidas adicionados em peles e couros, para prevenir a contaminação dos mesmos por microrganismos, esta dissertação centrou-se na avaliação do desempenho de microbicidas comerciais convencionalmente utilizados na indústria do couro sendo eles 2-(tiocianometiltio) benzotiazole (TCMTB), isotiazolina, dispersão oleosa de 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/óleo), dispersão aquosa de 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/água), 2-n-octil-4-isotiazolin-3-ona (OIT) e para-cloro-meta-cresol (PCMC) contra as espécies de bactérias Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa e Streptomyces sp. e as espécies de fungos Aspergillus niger, Aspergillus flavus, Penicillium herguei e Penicillium chrysogenum. Os microbicidas foram aplicados nas etapas de remolho, píquel, curtimento de couro com cromo e curtimento/engraxe com tanino vegetal. Os efeitos antimicrobianos dos microbicidas foram avaliados através de ensaios microbiológicos acelerados de plaqueamento e de acondicionamento em câmara tropical e testes de biodeterioração no solo, seguidos de análises visual, Microscopia eletrônica de varredura e ensaio de tração. Também foi testada a sorção e wash-out dos microbicidas em couros wet-blue. Outro teste feito nos próprios microbicidas foi o de concentração inibitória mínima (MIC). Os resultados demonstraram baixa capacidade antibacteriana e antifúngica dos microbicidas selecionados quando aplicados no processo de remolho contra o ataque das bactérias Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Streptomyces sp. e no processo de engraxe para o couro curtido com tanino vegetal contra o ataque dos fungos Aspergillus niger, Aspergillus flavus. Dois dos microbicidas estudados, TCMTB e OIT+BMC/água aplicados no couro wet-blue, revelaram elevada capacidade antifúngica contra os quatro diferentes fungos testados. Dos microbicidas submetidos ao teste de absortividade e wash-out, o microbicida à base de TCMTB apresentou alta e rápida absortividade pelo couro wet-blue, além de possuir resistência à lavagem. / A problem in the leather industry is the deterioration of leather skins due to the development of microorganisms, in the processing of leather. The skin and leather containing nutrients suitable for the growth of microorganisms such as carbohydrates, fats and proteins , as well as environmental conditions, high humidity, storage temperature and pH favorable. Some genera of bacteria and fungi synthesize important ingredients of this substrate, causing harmful changes in the surface of the leather and the physical and mechanical properties, leaving pigmented spots are difficult to remove, affecting the quality of the final product and loss of commercial value. Thus, there arises the need to develop strategies for control of microorganisms in order to reduce or eliminate this problem, therefore, appeal commonly the use of microbicides. In the past, the expected action of antimicrobial agents was mainly to provide effective protection, but in more recent years, concerns about the toxicity and potential ecological risks has also become important. Nowadays a major global concern is the careful preservation of the environment, due to this many researches are focused on the development of new clean and renewable technologies as well as process optimization. In view of the improvement of processes in respect to the use of microbicides added to hides and skins to prevent contamination thereof by microorganisms , this work has focused on the evaluation of the performance of commercial microbicides conventionally used in the leather industry, 2-metiltiocianato benzothiazole (TCMTB) isothiazoline, oily dispersion of 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/oil), water dispersion of 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/water), 2-n-octil-4-isotiazolin-3-ona (OIT) and para-chloro-meta-cresol (PCMC), against the bacterial species Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosas and Streptomyces sp. e species of fungi Aspergillus niger, Aspergillus flavus, and Penicillium herguei Penicillium chrysogenum, compared with the control. Microbicides were applied in steps of soaking, pickling, chrome tanning and grease/tanning with vegetable tannin. The antimicrobial effects of microbicides made for these applications were evaluated by accelerated plating microbiological testing and tropical chamber rain and biodegradation tests on the ground, followed by analysis (visual , SEM and tensile test) . Also was tested the absorptivity and wash-out of microbicides in wet-blue leather. Another test done on their own microbicides was the minimal inhibitory concentration (MIC). The results showed low capacity antibacterial and antifungal activities of selected microbicides when applied in the process of soaking the attack of the bacteria Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Streptomyces. sp. e in the process of grease for leather vegetable tannin against fungal attack Aspergillus niger, Aspergillus flavus. Two of microbicides studied TCMTB and OIT + BMC/water applied in wet-blue leather, high capacity antifungal against revealed four different fungi tested. For microbicides tested for absorbency and wash-out the microbicide based TCMTB showed high and rapid absorbency by wet-blue leather also has resistance to washing.
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Desempenho de microbicidas para preservação de peles e courosFontoura, Juliana Tolfo da January 2013 (has links)
Um problema na indústria coureira é a deterioração de peles e couros devido ao desenvolvimento de microrganismos no processamento do couro. As peles e os couros contêm nutrientes adequados para o crescimento de microrganismos, como carboidratos, gorduras e proteínas, além das condições ambientais, alta umidade, temperatura de armazenagem e pH favoráveis. Alguns gêneros de bactérias e fungos sintetizam importantes substâncias deste substrato, causando modificações prejudiciais na superfície do couro e nas propriedades físico-mecânicas, deixando manchas pigmentadas de difícil remoção, afetando a qualidade do produto final e causando perda de valor comercial. Desta forma, surge a necessidade de desenvolver estratégias de controle dos microrganismos de modo a reduzir ou eliminar este problema. Para tanto, recorre-se comumente à utilização de microbicidas. No passado, a ação esperada dos agentes antimicrobianos era principalmente de fornecer uma proteção eficaz, mas em anos mais recentes, a preocupação com a sua toxicidade e com potenciais riscos ecológicos tornou-se também importante. Nos dias atuais uma grande preocupação mundial é o cuidado com a preservação do meio ambiente. Devido a isto, várias pesquisas estão voltadas para o desenvolvimento de novas tecnologias limpas e renováveis como também a otimização de processos. Tendo em vista a melhoria de processos no que diz respeito ao uso de microbicidas adicionados em peles e couros, para prevenir a contaminação dos mesmos por microrganismos, esta dissertação centrou-se na avaliação do desempenho de microbicidas comerciais convencionalmente utilizados na indústria do couro sendo eles 2-(tiocianometiltio) benzotiazole (TCMTB), isotiazolina, dispersão oleosa de 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/óleo), dispersão aquosa de 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/água), 2-n-octil-4-isotiazolin-3-ona (OIT) e para-cloro-meta-cresol (PCMC) contra as espécies de bactérias Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa e Streptomyces sp. e as espécies de fungos Aspergillus niger, Aspergillus flavus, Penicillium herguei e Penicillium chrysogenum. Os microbicidas foram aplicados nas etapas de remolho, píquel, curtimento de couro com cromo e curtimento/engraxe com tanino vegetal. Os efeitos antimicrobianos dos microbicidas foram avaliados através de ensaios microbiológicos acelerados de plaqueamento e de acondicionamento em câmara tropical e testes de biodeterioração no solo, seguidos de análises visual, Microscopia eletrônica de varredura e ensaio de tração. Também foi testada a sorção e wash-out dos microbicidas em couros wet-blue. Outro teste feito nos próprios microbicidas foi o de concentração inibitória mínima (MIC). Os resultados demonstraram baixa capacidade antibacteriana e antifúngica dos microbicidas selecionados quando aplicados no processo de remolho contra o ataque das bactérias Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Streptomyces sp. e no processo de engraxe para o couro curtido com tanino vegetal contra o ataque dos fungos Aspergillus niger, Aspergillus flavus. Dois dos microbicidas estudados, TCMTB e OIT+BMC/água aplicados no couro wet-blue, revelaram elevada capacidade antifúngica contra os quatro diferentes fungos testados. Dos microbicidas submetidos ao teste de absortividade e wash-out, o microbicida à base de TCMTB apresentou alta e rápida absortividade pelo couro wet-blue, além de possuir resistência à lavagem. / A problem in the leather industry is the deterioration of leather skins due to the development of microorganisms, in the processing of leather. The skin and leather containing nutrients suitable for the growth of microorganisms such as carbohydrates, fats and proteins , as well as environmental conditions, high humidity, storage temperature and pH favorable. Some genera of bacteria and fungi synthesize important ingredients of this substrate, causing harmful changes in the surface of the leather and the physical and mechanical properties, leaving pigmented spots are difficult to remove, affecting the quality of the final product and loss of commercial value. Thus, there arises the need to develop strategies for control of microorganisms in order to reduce or eliminate this problem, therefore, appeal commonly the use of microbicides. In the past, the expected action of antimicrobial agents was mainly to provide effective protection, but in more recent years, concerns about the toxicity and potential ecological risks has also become important. Nowadays a major global concern is the careful preservation of the environment, due to this many researches are focused on the development of new clean and renewable technologies as well as process optimization. In view of the improvement of processes in respect to the use of microbicides added to hides and skins to prevent contamination thereof by microorganisms , this work has focused on the evaluation of the performance of commercial microbicides conventionally used in the leather industry, 2-metiltiocianato benzothiazole (TCMTB) isothiazoline, oily dispersion of 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/oil), water dispersion of 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/water), 2-n-octil-4-isotiazolin-3-ona (OIT) and para-chloro-meta-cresol (PCMC), against the bacterial species Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosas and Streptomyces sp. e species of fungi Aspergillus niger, Aspergillus flavus, and Penicillium herguei Penicillium chrysogenum, compared with the control. Microbicides were applied in steps of soaking, pickling, chrome tanning and grease/tanning with vegetable tannin. The antimicrobial effects of microbicides made for these applications were evaluated by accelerated plating microbiological testing and tropical chamber rain and biodegradation tests on the ground, followed by analysis (visual , SEM and tensile test) . Also was tested the absorptivity and wash-out of microbicides in wet-blue leather. Another test done on their own microbicides was the minimal inhibitory concentration (MIC). The results showed low capacity antibacterial and antifungal activities of selected microbicides when applied in the process of soaking the attack of the bacteria Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Streptomyces. sp. e in the process of grease for leather vegetable tannin against fungal attack Aspergillus niger, Aspergillus flavus. Two of microbicides studied TCMTB and OIT + BMC/water applied in wet-blue leather, high capacity antifungal against revealed four different fungi tested. For microbicides tested for absorbency and wash-out the microbicide based TCMTB showed high and rapid absorbency by wet-blue leather also has resistance to washing.
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Desempenho de microbicidas para preservação de peles e courosFontoura, Juliana Tolfo da January 2013 (has links)
Um problema na indústria coureira é a deterioração de peles e couros devido ao desenvolvimento de microrganismos no processamento do couro. As peles e os couros contêm nutrientes adequados para o crescimento de microrganismos, como carboidratos, gorduras e proteínas, além das condições ambientais, alta umidade, temperatura de armazenagem e pH favoráveis. Alguns gêneros de bactérias e fungos sintetizam importantes substâncias deste substrato, causando modificações prejudiciais na superfície do couro e nas propriedades físico-mecânicas, deixando manchas pigmentadas de difícil remoção, afetando a qualidade do produto final e causando perda de valor comercial. Desta forma, surge a necessidade de desenvolver estratégias de controle dos microrganismos de modo a reduzir ou eliminar este problema. Para tanto, recorre-se comumente à utilização de microbicidas. No passado, a ação esperada dos agentes antimicrobianos era principalmente de fornecer uma proteção eficaz, mas em anos mais recentes, a preocupação com a sua toxicidade e com potenciais riscos ecológicos tornou-se também importante. Nos dias atuais uma grande preocupação mundial é o cuidado com a preservação do meio ambiente. Devido a isto, várias pesquisas estão voltadas para o desenvolvimento de novas tecnologias limpas e renováveis como também a otimização de processos. Tendo em vista a melhoria de processos no que diz respeito ao uso de microbicidas adicionados em peles e couros, para prevenir a contaminação dos mesmos por microrganismos, esta dissertação centrou-se na avaliação do desempenho de microbicidas comerciais convencionalmente utilizados na indústria do couro sendo eles 2-(tiocianometiltio) benzotiazole (TCMTB), isotiazolina, dispersão oleosa de 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/óleo), dispersão aquosa de 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/água), 2-n-octil-4-isotiazolin-3-ona (OIT) e para-cloro-meta-cresol (PCMC) contra as espécies de bactérias Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa e Streptomyces sp. e as espécies de fungos Aspergillus niger, Aspergillus flavus, Penicillium herguei e Penicillium chrysogenum. Os microbicidas foram aplicados nas etapas de remolho, píquel, curtimento de couro com cromo e curtimento/engraxe com tanino vegetal. Os efeitos antimicrobianos dos microbicidas foram avaliados através de ensaios microbiológicos acelerados de plaqueamento e de acondicionamento em câmara tropical e testes de biodeterioração no solo, seguidos de análises visual, Microscopia eletrônica de varredura e ensaio de tração. Também foi testada a sorção e wash-out dos microbicidas em couros wet-blue. Outro teste feito nos próprios microbicidas foi o de concentração inibitória mínima (MIC). Os resultados demonstraram baixa capacidade antibacteriana e antifúngica dos microbicidas selecionados quando aplicados no processo de remolho contra o ataque das bactérias Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Streptomyces sp. e no processo de engraxe para o couro curtido com tanino vegetal contra o ataque dos fungos Aspergillus niger, Aspergillus flavus. Dois dos microbicidas estudados, TCMTB e OIT+BMC/água aplicados no couro wet-blue, revelaram elevada capacidade antifúngica contra os quatro diferentes fungos testados. Dos microbicidas submetidos ao teste de absortividade e wash-out, o microbicida à base de TCMTB apresentou alta e rápida absortividade pelo couro wet-blue, além de possuir resistência à lavagem. / A problem in the leather industry is the deterioration of leather skins due to the development of microorganisms, in the processing of leather. The skin and leather containing nutrients suitable for the growth of microorganisms such as carbohydrates, fats and proteins , as well as environmental conditions, high humidity, storage temperature and pH favorable. Some genera of bacteria and fungi synthesize important ingredients of this substrate, causing harmful changes in the surface of the leather and the physical and mechanical properties, leaving pigmented spots are difficult to remove, affecting the quality of the final product and loss of commercial value. Thus, there arises the need to develop strategies for control of microorganisms in order to reduce or eliminate this problem, therefore, appeal commonly the use of microbicides. In the past, the expected action of antimicrobial agents was mainly to provide effective protection, but in more recent years, concerns about the toxicity and potential ecological risks has also become important. Nowadays a major global concern is the careful preservation of the environment, due to this many researches are focused on the development of new clean and renewable technologies as well as process optimization. In view of the improvement of processes in respect to the use of microbicides added to hides and skins to prevent contamination thereof by microorganisms , this work has focused on the evaluation of the performance of commercial microbicides conventionally used in the leather industry, 2-metiltiocianato benzothiazole (TCMTB) isothiazoline, oily dispersion of 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/oil), water dispersion of 2-n-octil-4-isotiazolin-3-ona + carbendazim (OIT+BMC/water), 2-n-octil-4-isotiazolin-3-ona (OIT) and para-chloro-meta-cresol (PCMC), against the bacterial species Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosas and Streptomyces sp. e species of fungi Aspergillus niger, Aspergillus flavus, and Penicillium herguei Penicillium chrysogenum, compared with the control. Microbicides were applied in steps of soaking, pickling, chrome tanning and grease/tanning with vegetable tannin. The antimicrobial effects of microbicides made for these applications were evaluated by accelerated plating microbiological testing and tropical chamber rain and biodegradation tests on the ground, followed by analysis (visual , SEM and tensile test) . Also was tested the absorptivity and wash-out of microbicides in wet-blue leather. Another test done on their own microbicides was the minimal inhibitory concentration (MIC). The results showed low capacity antibacterial and antifungal activities of selected microbicides when applied in the process of soaking the attack of the bacteria Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Streptomyces. sp. e in the process of grease for leather vegetable tannin against fungal attack Aspergillus niger, Aspergillus flavus. Two of microbicides studied TCMTB and OIT + BMC/water applied in wet-blue leather, high capacity antifungal against revealed four different fungi tested. For microbicides tested for absorbency and wash-out the microbicide based TCMTB showed high and rapid absorbency by wet-blue leather also has resistance to washing.
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Impact of weekend admission on in-hospital mortality in severe community-acquired pneumonia patients in Japan / 重症市中肺炎における週末入院の退院時死亡に与える影響Uematsu, Hironori 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(社会健康医学) / 甲第20288号 / 社医博第77号 / 社新制||医||9(附属図書館) / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 川上 浩司, 教授 一山 智, 教授 伊達 洋至 / 学位規則第4条第1項該当 / Doctor of Public Health / Kyoto University / DGAM
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Construction and development of bioluminescent Pseudomonas aeruginosa strains : application in biosensors for preservative efficacy testingShah, Niksha Chimanlal Meghji January 2014 (has links)
Whole cell biosensors have been extensively used for monitoring toxicity and contamination of compounds in environmental biology and microbial ecology. However, their application in the pharmaceutical and cosmetics industries for preservative efficacy testing (PET) has been limited. According to several pharmacopoeias, preservatives should be tested for microbial activity using traditional viable count techniques; the use of whole cell microbial biosensors potentially provides an alternative, fast, and efficient method. The aim of the study was to construct and develop whole cell microbial biosensors with Pseudomonas aeruginosa ATCC 9027. Constitutive promoters: PlysS, Pspc, Ptat, Plpp and PldcC and the lux-cassette were inserted into plasmid pME4510 and transformed into P. aeruginosa ATCC 9027 cells to produce bioluminescent strains. Plasmids were found to be maintained stably (~50 copies per cell) throughout the growth and death cycle. The novel bioluminescent strains were validated in accordance with the pharmacopoeia using bioluminescence detection and quantification followed by comparison with the traditional plate counting method. The bioluminescent method was found to be accurate, precise and equivalent at a range of 103 – 107 CFU/mL, as compared with plate counting. Recovery of bacterial cells was quantified using bioluminescence; this method proved to be accurate with percentage recoveries between 70-130% for all bioluminescent strains. The method was also more precise (relative standard deviation less than 15%) than the traditional plate counting method or the ATP bioluminescent method. Therefore, the bioluminescent constructs passed/exceeded pharmacopoeial specified criteria for range, limit of detection, accuracy, precision and equivalence. Physiology of the validated bioluminescent strains was studied by assessing the growth and death patterns using constitutive gene expression linked with bacterial replication. Promoter strengths were evaluated at various stages of the growth and death pattern and related to promoter sequences. PlysS, Ptat and Plpp were relatively strong promoters whilst PldcC and Pspc were relatively weak promoters. Relative promoter strength decreased in the order of Plpp>Ptat>PlysS>PldcC>Pspc during the exponential phase whilst Ptat was stronger than Plpp during the stationary phase of growth. Plpp had its highest level of expression during the exponential phase, while Ptat had relatively stable lux expression during the stationary phase. Correlations between relative bioluminescence and CFU at 24 hours were greater than 0.9 indicating a strong relationship for all bioluminescent strains. Reduction in correlation coefficients to approximately 0.6 between relative bioluminescence and CFU and between relative fluorescence and CFU beyond 24 hours indicated that a certain proportion of cells were viable but non-culturable. Tat-pME-lux showed steady bioluminescence compared to CFU count (R>0.9) throughout 28 days of growth. Equivalence analysis showed no significant difference between the bioluminescence and plate count method throughout 28 days of growth for all five bioluminescent strains. Applicability of these novel bioluminescent strains was evaluated for preservative efficacy tests (PET) using bacterial replication and bioluminescence as a measure of constitutive gene expression. PET using benzalkonium chloride and benzyl alcohol showed no significant difference between the bioluminescent method and the plate count method. Good correlations between bioluminescence, CFU count and fluorescence were obtained for benzalkonium chloride (BKC) concentrations (R>0.9) between 0.0003% and 0.0025% against strains lysR25, lppR4 and tatH5. Similarly, good correlations (R>0.9) between the three parameters were obtained for benzyl alcohol (BA) concentrations between 0.125% and 2% against strains lysR25, lppR4 and tatH5. The bioluminescent method and traditional plate counting method were equivalent for concentrations of BKC (0.0003 - 0.02%) and BA (0.25 - 2%) during preservative efficacy tests. These bioluminescent constructs therefore are good candidates for selection for preservative efficacy testing. The bioluminescent method and traditional plate counting method were also found to be equivalent for construct tatH5 at a concentration of 0.125% BA. PET testing with BKC and BA showed that tatH5-pMElux (R>0.9) had consistently high correlation coefficients between CFU and relative bioluminescence. Together with the results from growth and death kinetics, where tatH5 showed the greatest constitutive expression, it can be concluded that P. aeruginosa ATCC 9027 tatH5-pMElux is the best construct for testing various antimicrobial agents. This study has shown that according to the pharmacopoeial requirements, the bioluminescent method is more accurate, precise and equivalent to the traditional plate counting method and therefore can be utilised instead of the traditional plate counting method for the purpose of preservative efficacy testing.
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