Thesis (PhD Microbiology and Plant Pathology(Water resource management))-University of Pretoria, 2006. / Summary in English. Includes bibliographical references. Available on the Internet via the World Wide Web.

Thesis (Ph. D.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (leaves 170-182). Also available via the World Wide Web.

Thesis (doctoral)--Lund University, 1999. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (doctoral)--Lund University, 1999. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (Ph. D.)--University of Canterbury, 2005. / Typescript (photocopy). Includes bibliographical references (leaves 140-159). Also available via the World Wide Web.

Orientador : Pilar Rodriguez de Massaguer / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-07-27T23:05:00Z (GMT). No. of bitstreams: 1 Pacheco_CristianadePaula_M.pdf: 30708088 bytes, checksum: 59a1557e174323a06128bf85a7040675 (MD5) Previous issue date: 2001 / Resumo: O resumo podera ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic digital document / Mestrado / Mestre em Ciência de Alimentos

Orientador: Glaucia Maria Pastore / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-03T19:41:07Z (GMT). No. of bitstreams: 1 Taffarello_LucianaAfonsoBittar_M.pdf: 2253767 bytes, checksum: 70c3e5e760bb9173c47a6d67e497a396 (MD5) Previous issue date: 2004 / Mestrado

Orientador: Telma Teixeira Franco / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-07-25T20:58:05Z (GMT). No. of bitstreams: 1 Bim_MonicaAndrea_M.pdf: 4401190 bytes, checksum: 58cf555e454e041ffe09f9a7a32378ae (MD5) Previous issue date: 1999 / Resumo: A xilana, a qual é hidrolisada pela xilanase, é um abundante biopolímero encontrado no tecido de vegetais como constituinte principal da parede celular. Muitas das xilanases comercialmente disponíveis são produzidas por fungos com atividade ótima a pHs ácidos ou neutros e a temperaturas abaixo de 45°C. Existem várias aplicações para a xilanase, mas o seu maior potencial de uso é na industria de papel e celulose nos processos de branqueamento da polpa. Deste modo, xilanases ativas em condições alcalinas são potencialmente úteis nos processos de branqueamento de polpa de papel sem necessidade de mudanças no pH do processo e com a vantagem de diminuir a quantidade de componentes organoclorados nos efluentes das indústrias de papel. As duas motivações principais deste trabalho foram: primeiro, utilizar sistema de duas fases aquosas (SDFA) para extrair e purificar a xilanase do caldo de fermentação, produzido por Bacillus pumilus, pois o uso de SDFA pode ser uma alternativa mais econômica e de fácil operação, para purificação de bioprodutos, visto que as etapas de extração e purificação representam até 80% do custo destes bioprodutos. Segundo, aplicar a xilanase no branqueamento da polpa kraft de eucalipto visando a redução de organoclorados no efluente das indústrias de papel e celulose ...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Xylan, a group of heteropolysaccharides, is an abundant biopolymer found in plant tissues as major component of cell wall, which is hydrolysed by xylanase. Several of the xylanases commercially available produced by fungi are active at neutral or acidic pH and their optimum temperature is below 45°C. Various applications for xylanases in bioconversion and food industries have been suggested and one of the major potential applications of xylanases involves the pulp and paper industry. This way, enzymes which are active at alkaline conditions have great potential in bleaching process without any need for changes in pH and with the advantage in lowering the release of polluting organic chlorine compounds. The two main motivations of this work was: first, to extract and to purify the enzyme from the crude fermentation broth, produced by Bacillus pumilus, using aqueous two phase systems (ATPS). Second, application ofxylanase ftom crude fermentation broth at hardwood kraft pulp bleaching. The enzyme from crude fermentation broth was extracted by partitioning in ATPS composed of phosphate and polyethyleneglycol (pEG). The effect of tie-line length, PEG molecular weight and NaCl and phosphate concentrations upon the purification factors and yields of xylanase were investigated by statistical design. The best system studied was that one containing 22% PEG6000, 10%¿K IND. 2¿¿HP¿O IND. 4¿ and 12% NaCl with a purification factor of 40 and 97% yield of enzyme activity ...Note: The complete abstract is available with the full electronic digital thesis or dissertations / Mestrado / Mestre em Engenharia Química

Orientador : Vanderlei Perez Canhos / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-07-18T15:49:20Z (GMT). No. of bitstreams: 1 Kaji_DeniseAkiko_D.pdf: 5928225 bytes, checksum: 2d2fec6671a89cddc1769763cf34ecc3 (MD5) Previous issue date: 1993 / Resumo: Foi efetuado um estudo taxômico de 15 isolados entomopatogênicos de mostras de solos e insetos do Brasil com características de bactérias aeróbias, formadoras de endosporos e presença de cristal. Treze isolados acarretaram 100 % de mortalidade a larvas de Aedes fluviatilis em leituras observadas a 24 h. Os resultados dos testes de caracterização morfológica, bioquímica e fisiológica indicaram que 14 isolados pertencem a espécie Bacillus thuringiensis (B.t.) enquanto que o 15° foi determinado como Bacillus sphaericus (B.s.). Através dos perfis eletroforéticos de proteínas totais 11 B.t. isolados foram identificados como subespécie israelensis (sorotipo H-14, incluindo duas linhagens não sorotipadas), 1 como kurstaki (soro tipo H3a, 3b) e 1 como morT!isoni (sorotipo H8a, 8b). As linhagens de B. thuringiensis subsp. israelensis (B.t.i.) formaram um grupo homogêneo distinto das linhagens de referências tóxicas. a lepidópteros e coleópteros. O isolado identificado como B. sphaericus demonstrou alta similaridade com a linhagem 2362 através de testes de atividade larVicida; fagotipagem (fagotipo 3) e sorologia (H5). Os 11 isolados identificados como B.t.i. pela sorologia e/ou perfIS eletroforéticos de proteínas totais não apresentaram polimorflsmo quanto aos fragmentos de restrição, quando foram utilizadas sondas do gene 16S rRNA e do cristal de B.t.i.. A sonda do gene toxigêniro de B.t.i. demonstrou ser bastante específica para a subespécie israelensis, não apresentando hibridizaçóes Com outras subespécies. O gene do cristal de B.t.i. de referência IPS82 e isolados identificados como B.t.i. foram amplificados através da reação em cadeia da polimerase (PCR), digeridos com Sau3AI e separados por eletroforese. Os perfis de restrição destes fragmentos foram idênticos. Esses resultados indicam que os B.t.i. isolados no Brasil formam uni grupo. homogêneo e de organização genética bastante conservada. Outras 28 linhagens de referência representando 12 subespécies de B.t. com 9 sorotipos diferentes, 4 B. cereus e 4 B. anthracis foram incluídas na análise do perfil de hibridização com o gene 16S rRNA Os dados obtidos mostraram correspondência com os testes de sorologia (DE BARJAC & FRACHON, 1990) e a taxonomia numérica (PRIEST et ai., 1988) / Abstract: Fifteen bacterial isolates from Brazilian soil and insects with aerobic, endospores and crystal characteristics were taxonomically analysed. Thirteen strains were shown to be pathogenic to Aedes fluviatilis larvae causing 100 % mortality in 24 hours and two strains were non-pathogenic. The results of morphological, biochemical and physiological tests indicated that 14 strains belong B. thuringiensis (8.t.) while the remaining strain was identified as B. sphaericus. Electrophoresis ofwhole celI protein patterns helped in the identification of eleven isolates as israelensis (serotype H-14, including two non-serotypable strains), 1 as kurstaki (serotype H3a, 3b) and 1 as morrisoni (serotype H8a, 8b). Moreover, it was shown that alI B. thuringiensis subsp. israelensis (8.t.i.) strains. formed a homogenous group distinct from reference strains toxic for Lepidoptera or Coleoptera. The isolate identified as B. sphaericus presented high similarity with strain 2362 by larvicidal tests, phagotyping (group 3) and serotyping (H5). The is.olates identified as subspecies israelensis by serology and/or electrophoresis of whole cell proteins patterns showed the same patterns using restriction fragments length polymorphisms (RFLPs) analysis with the 16S rRNA and the crystal gene of B.t.i. as probes. The crystal gene of B.t.i. used as the probe was specific only to the subspecies israelensis. The crystal gene of B.t.i. reference (IPS82) and isolated strains of B.t.i. were amplified by Polymerase Chain Reaction (PCR), digested with Sau3AI and electrophoresed in agarose gel. The restriction fragment patterns obtained were identical. It confirmed as stated above that the B.t.i. isolates used in this study are a highly homogenous group with a conserva tive. genetic organization. Furthermore, 28B.t. reference strains representing 12 subspecies (with 9 different serotypes), 4 B. cereus and 4. B. anthracis were compared with regard to their ribosomal RNA gene restriction patterns. The results obtained match the serological tests (DEBARJAC & FRACHON, 1990) and numerical taxonomy studies (PRIEST et al., 1988). The results in this study suggest that the techniques could be an altemative to serological tests / Doutorado / Doutor em Ciência de Alimentos

The object of the present investigation was to determine quantitatively the extent of glucose and d- and l-arabinose utilization in order to separate it from the other two factors influencing the pH change in the medium. The pH of the carbohydrate media employed was determined potentiometrically, using a glass electrode in order that the pH produced could be compared with the extent of utilization of these carbohydrates. Likewise, the pH produced by the same <i>Bacilli</i> in peptone alone was determined so that it could be compared with the pH produced in the carbohydrate-peptone media. The fundamental observations concerned with the metabolism of the genus <i>Bacillus</i> (which may be derived from this study) may be of value in the taxonomic identification of various members of this group of organisms, and might lead to other interesting conclusions regarding the metabolism of these organisms in pure laboratory culture and also in mixed cultures in the natural habitat. / Ph. D.