Thesis (M. Sc.)--Brock University, 2005. / Includes bibliographical references (leaves 134-165).

Made available in DSpace on 2015-07-22T20:50:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-27 / Em vista do crescimento de infecções fúngicas oportunisticas causadas por Fusarium spp. e da resistência do fungo aos antifúngicos frequentemente utilizados, o estudo visa avaliar o perfil de sensibilidade das associações entre terbinafina, itraconazol, cetoconazol e anfotericina B frente a 20 isolados clínicos e ambientais de Fusarium solani, e verificar fatores associados a virulência como pesquisa de melanina na parede celular e a produção das enzimas extracelulares proteinase, fosfolipase, lipase e DNAse. Anfotericina B associada à itraconazol demonstrou efeito sinérgico em 15% dos isolados, sendo 33% de origem ambiental e 65% de origem clínica. Efeitos sinérgicos foram obtidos contra 10% dos isolados na associação entre anfotericina B e cetoconazol e contra 5% na associação entre anfotericina B e terbinafina. Nossos resultados revelaram efeitos aditivos e indiferentes contra as cepas testadas nas associações entre terbinafina e derivados azólicos. Não foi detectada presença de melanina na parede de F. solani. As culturas de F. solani clínicas e ambientais apresentaram atividade enzimática de proteinase positiva após coloração com ácido acético e negro de amido, com formação de halos ao redor da colônia na proporção de 30% e 45% respectivamente. Atividades enzimáticas de lipase, fosfolipase e DNAse não foram detectadas, contudo, não é possível afirmar que F. solani não produza essas enzimas, considerando que as mesmas podem ser mantidas intracelularmente e não liberadas para o meio. / Despite of the increase of opportunistic fungal infections caused by Fusarium spp. and their resistance to antifungal drugs, the aims of this study were to evaluate susceptibility profiles of 20 clinical and environmental isolates of Fusarium solani against the associations among terbinafine, itraconazole, ketoconazole and amphotericin B, and to verify the presence of associated virulence factors as melanin and extracellular enzymes (proteinase, phospholipase, lipase and DNAse). Amphotericin B combined with itraconazole showed synergism against 15% of the isolates, 33% of these was from the environment and 65% from clinical cases. Synergistic effect was observed against 10% of strains tested by association between amphotericin B and ketoconazole and against 5% in association between anphotericin B and terbinafine. The associations between terbinafine and azole derivatives showed additive effect and no difference against the samples. Presence of melanin in the F. solani cell wall was not observed. Both, clinical and environmental isolates expressed enzymatic activity of proteinase in 30% and 45% of cases. Enzymatic activity of lipase, phospholipase and DNAse were not detected; however, it was not possible to state that F. solani do not produce these enzymes, as they could manteined intracellularly and would not released to the environment. / TEDE / BV UNIFESP: Teses e dissertações

This work is aimed for Actinobacteria and describes their importance in Arctic soil. The members of Actinobacteria are known for their ability to decompose complex natural biopolymers and because they are able to live in harsh arctic environment they could play there an important role in organic matter decomposition. The work compares their abundance in different soil horizons with the focus on cryoturbations and determines the influence of temperature on their amount. This work also represents the results of testing pure Actinobacterial isolates for the production of cellulolytic enzymes.

No description available.

Litter decomposition requires the presence of corresponding degradative enzymes, produced mainly by fungi. Forest soils show considerable spatial heterogeneity of distribution of these enzymes at diferent scales. Moreover, enzyme pruduction varies during the year, usually accompanied by the change in fungal community composition. In this work I examined if this spatial heterogeneity can be seen even at a scale of an individual leaf and whether the fungal community differs among enzyme activity hotspots and inactive parts of the leaves. Another goal was isolation of celulytic fungi from cellulose litterbags incubated on forest floor using particle filtration and dilution-to-extinction method. In a broadleaved forest dominated by oak leaves at different stages of decay were collected: senescent leaves on twigs, and leaves after 2, 10 and 22 months of decomposition. Ten leaves per season were taken for analysis of cellobiohydrolase activity over the leaf surface. Leaves were attachmed onto melted agarose plate and leaf surface was covered with low melting point agarose containing fluorescently labelled substrate. For each leaf a map of enzyme activity was created and area with the high and low enzyme activity was identified. From both sites a square of approx. 1 cm2 was cut out, DNA was extracted and fungal...

Les champignons saprophytes sont les acteurs principaux du recyclage de la matière organique morte au sein des écosystèmes forestiers. Ces microorganismes possèdent la capacité unique de dégrader la totalité des polymères constitutifs du bois. L'analyse de la structuration des communautés durant les stades initiaux de la colonisation du bois par séquençage à haut débit a révélé que celui-ci influence la distribution et la dynamique des communautés qui lui sont associées. A l'échelle de l'organisme, les différents groupes écologiques de champignons décomposeurs du bois possèdent des systèmes de dégradation extracellulaires reflétant cette complexité chimique. Le séquençage du génome d'un grand nombre de ces organismes a permis l'identification de superfamilles d'enzymes impliquées dans les mécanismes de résistance et de détoxication des composés toxiques exogènes. Parmi elles, la superfamille des glutathion transférases présente une extension de classes spécifiques au sein des champignons décomposeurs du bois. La détermination des propriétés biochimiques et structurales d'une isoforme, issue d'une de ces classes spécifique (les Etherase-like), présente chez Phanerochaete chrysosporium a révélé des caractéristiques particulières. Cette enzyme possède un mode de dimérisation atypique ainsi que la capacité à séquestrer des composés phénoliques toxiques via une propriété ligandine unique. La comparaison des propriétés de plusieurs isoformes de cette classe d'enzymes appartenant aux champignons C. cinereus et P. chrysosporium a démontré que celle-ci exhibe une grande versatilité intra- et interspécifique, de leurs activités enzymatiques et de leur propriété ligandine / Saprophytic fungi are key players of dead organic matter recycling in forest ecosystems. These microorganisms possess the unique ability to degrade the integrality of wood constitutive polymers by secretion of complex oxydative and hydrolytic enzymatic systems. Communities structuration analysis during the initial stages of wood colonisation by high throughput sequencing revealed that the latter beyond being a source of nutrients, influences the distribution and dynamic of communities by its broad chemical variability. At the organism level, the different ecological groups of wood decomposing fungi possess extracellular degradation systems reflecting this chemical complexity. Genome sequencing of these organisms allowed the identification of enzymes superfamilies involved in resistance and detoxification mechanisms towards exogenous toxic compounds. Among them, the glutathione transferases superfamily exhibit extension of specific classes in wood decaying basidiomycetes. Biochemical and structural properties determination of one isoform belonging to one of these specific classes (the Etherase-like), found in Phanerochaete chrysosporium revealed unusual characteristics. This enzyme possesses an atypical dimerization mode as well as the ability to sequestrate toxic phenolic compounds resulting from wood degradation through a unique ligandin property. Properties comparison of several isoforms from this class belonging to C. cinereus and P.chrysosporium demonstrated a huge intra- and interspecific versatility of their enzymatics activities and ligandin property in response to environmental constraints arising from the great chemical heterogeneity of wood composition

Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2016. / Waste management in winery and distillery industries faces numerous disposal challenges as large volumes of both liquid and solid waste by-products are generated yearly during cellar practices. Composting has been suggested a feasible option to beneficiate solid organic waste. This incentivized the quest for efficient composting protocols to be put in place. The objective of this study was to experiment with different composting strategies for spent winery solid waste. Compost materials consisting of chopped pruning grape stalks, skins, seed and spent wine filter material consisting of a mixture of organic and inorganic expend ingredients were mixed in compost heaps. The filter material component varied (in percentage) among five treatments: T1 (40%) lined, T2 (20%) lined, T3 (0%) lined, T4 (40%) grinded material, lined and T5 (40%) unlined. Composting was allowed to proceed in open air over 12 months, from autumn to summer. Indicators such as temperature, moisture, enzyme activities, microbial counts, pH, and C/N ratio, were recorded. Generally, season (df =3, 16, P < 0.05) had significant effects (df =1, 3, P < 0.05) on heap temperature and moisture in all treatments. Similarly, microorganisms (actinobacteria and heterotrophs) varied significantly in all treatments in response to seasonal change (df = 3, 16; P < 0.05). Enzyme activities fluctuated in accordance with seasonal factors and compost maturity stages, with phosphatases, esterases, amino-peptidases, proteases and glycosyl-hydrolases being most prominent. Compared to treatments T2 and T3, compost treatments with higher percentage waste filter materials (T1, T4 and T5) had higher N (16100-21300 mg/kg), P (1500-2300 mg/kg), K (19800-28200 mg/kg), neutral pH, and lower C/N ratios (13:1-10:1), which were also comparable with commercially produced composts. Filter materials therefore, appears to be a vital ingredient for composting of winery solid waste.

Orientador: Silvio Roberto Andrietta / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-09-11T21:08:51Z (GMT). No. of bitstreams: 1 Aquino_DeniseSilvade_M.pdf: 2817268 bytes, checksum: 75e30246006dba478e363bb0b37da638 (MD5) Previous issue date: 2006 / Resumo: Dextranas são polissacarídeos produzidos pela bactéria pertencente à família Lactobacileae constituídos de moléculas de glicose unidas por ligações a-(1-6) na cadeia principal e ligações a-(1-4), a-(1-3) e a-(1-2) nas ramificações. A enzima dextranasacarase, responsável por sua síntese, é extracelular e tem a sacarose como principal indutor. Este biopolímero possui aplicações nas indústrias farmacêuticas, químicas e de alimentos. Na indústria farmacêutica é que a dextrana tem a sua maior aplicação. A dextrana de baixa massa molecular, dextrana clínica, é utilizada como expansor volumétrico sanguíneo e como facilitador da fluidez do sangue. Este trabalho teve como objetivo otimizar o processo de produção de dextrana por três novas linhagens de bactérias denominadas 4-03, 4-30 e 4-26 isoladas da cana-de-açúcar, dentro deste objetivo principal estão incluídos a caracterização da estrutura de cadeia destes biopolímeros e a identificação das linhagens das bactérias isoladas. Para a otimização, tanto da produção de dextrana como da produção de dextrana-sacarase, realizaram-se ensaios em frascos agitados, analisando a influência das seguintes variáveis: concentração de tampão (controle do pH), concentração de substrato (sacarose) e concentração da fonte de nitrogênio (extrato de levedura). Conduziram-se os ensaios de otimização com base em planejamento experimental fatorial e análise de superfície de resposta. As linhagens 4-26 e 4-30 apresentaram modelos estatisticamente significativos, portanto, podem ser utilizados na previsão da composição do meio de fermentação para produção da dextrana-sacarase. Para a otimização da produção de dextrana, somente a linhagem 4-26 mostrou variação significativa estatisticamente das variáveis respostas frente ás variáveis estudadas na região avaliada. Realizaram-se ensaios para a obtenção da dextrana a qual teve sua estrutura de cadeia determinada utilizando o método da perioxidação e o método da degradação de Smith. A primeira metodologia consiste em determinar os tipos e as proporções das ligações a-(1-6), a-(1-4) e a-(1-2), e a-(1-3) por meio do consumo do oxidante e produção de ácido quando as dextranas são sujeitas a uma oxidação com periodato. A segunda metodologia citada, consiste na oxidação do polissacarídeo seguida de redução ao poliálcool correspondente e por fim realiza-se hidrólise ácida gerando fragmentos de Dgliceraldeído, característico de ligações a- (1,2), D-glicose, característico de ligações a-(1,3), eritritol, característico de ligações a- (1,4), glicerol e glicoaldeído, característicos de ligações a- (1,6) e terminal não-redutor. Quando compara-se os dois métodos de determinação da estrutura de cadeia da dextrana, a solubilidade em água da dextrana formada pela linhagem 4-03 é confirmada, pois a sua cadeia em ambas as análises apresentou uma maior porcentagem das ligações a-(1,6), característica contrária a goma produzida pela linhagem 4-30, que apresenta-se de forma insolúvel por ter uma cadeia ramificada. O resultado para o biopolímero formado pela linhagem 4-26 apresentou-se os mesmos valores para as duas metodologias, porém no método da degradação de Smith sua estrutura não aproximou-se da dextrana padrão / Abstract: Dextran is a polysaccharide produced by bacteria of the Lactobacillaceae family and it consists of D-glucose monomeric units linked at the position a-(1,6) in the linear chain and a-(1-4), a-(1-3) and a-(1-2) positions at the branching points. The enzyme dextransucrase, responsible for dextran synthesis, is extracellular and has sucrose as its main inductor. This biopolymer is used by the pharmaceutical, chemistry and the food industry. Dextran has its main application in the pharmaceutical industry. The low molecular weight dextran, the clinical dextran, is used as blood volume expander and blood flow improver. This work had as objective to optimize the dextran production by three new bacteria strains named 4-03, 4-26 and 4-30 isolated from sugar cane, into this main objective are including the characterization the structure of the chain of these bacteria biopolymers and to identification bacteria strains isolated. The influence of the following variable was analyzed for the dextransucrase and dextran production optimization: buffer (pH control), substrate (sucrose) and nitrogen source (yeast extract) concentrations. The experimental assays were performed on the basis of factorial design and response surface techniques. The strains 4-26 and 4-30 presented statically significant models, therefore, these models may be used for predict the optimum composition of the fermentation medium for dextransucrase production. Only strain 4-26 showed statically significant variation of the dependent variables in the evaluated region dextran production optimization. The dextran structure of the three strains was determined by the periodate oxidation and Smith degradation methods. The first methodology consist in to determine kinds and proportions of the a-(1,6), a-(1-2) e a-(1-4) e a-(1-3) linkages by the consumption of oxidant and the production of acid when the dextran is subject to periodate oxidation analysis. The second methodology consists in the oxidation of the polysaccharide followed by reduction and hydrolysis with dilute acid which produces characteristic fragments: D-glyceraldehydes, characteristic of the a-(1,2) linkages, D-glucose, characteristic of the a-(1,3) linkages, erythritol, characteristic of the a-(1,4) linkages and glycerol or glycolaldehyde, characteristic of the a-(1,6) linkages and no reducing terminal. The results obtained confirmed the high solubility of the dextran produced by strain 4-03 due to its high proportion of the a-(1,6) linkages in contrast with gum produced by strain 4- 30 that is highly insoluble due to its branched chain. The biopolymer produced by strain 4- 26 presented the same values for the both methodologies, however, the Smith degradation result showed that its structure is not close to the standard dextran / Mestrado / Desenvolvimento de Processos Biotecnologicos / Doutor em Engenharia Química

Submitted by Maike Costa (maiksebas@gmail.com) on 2017-02-17T14:23:55Z No. of bitstreams: 1 arquvo total.pdf: 2016983 bytes, checksum: d4a44272374a4acd45f6a231133da641 (MD5) / Made available in DSpace on 2017-02-17T14:23:55Z (GMT). No. of bitstreams: 1 arquvo total.pdf: 2016983 bytes, checksum: d4a44272374a4acd45f6a231133da641 (MD5) Previous issue date: 2016-11-25 / Beauveria bassiana is an entomopathogenic fungus used in the biological control of insect pests in agriculture. The production costs of its conidia, on a large scale, in the standard substrate (rice) currently used, affects the production process. Finding alternatives as a way of minimizing process costs has led to the need to investigate the efficiency of alternative substrates that, in addition to important nutritional properties, have high availability and low cost. Entomopathogenic fungi produce enzymes that are involved in the process of pathogenicity and virulence. However, when stimulated by specific substrates they can produce enzymes of biotechnological interest. Thus, the objective of this work was to analyze the potential of different substrates (algaroba fiber, malt residues, acerola seeds and fibers, and sugarcane bagasse) for conidiogenesis and enzymatic production (solid state fermentation) from of B. bassiana. The experiments for the production and viability of the conidia were carried out in triplicate, in erlernmeyer (250 mL) containing 30 g of each substrate, 0.3 μL of the conidial suspension (1 x 106 conidia/mL), humidity of 70 ± 10 % and Temperature (T = 29 ± 1 ° C). After 10 days of incubation, the rice substrates (standard medium) (2.00 × 106 conidia/g substrate), malt A (1.22 × 106 conidia/g), malt B (1.75 × 106 conidia/g), and algaroba fiber (2.36 x 106 conidia/g) provided higher conidia production. The viability of the conidia produced in these same substrates did not differ statistically among them, with a germination percentage of 99.96; 90.04; 93.17 and 98.21 %, respectively. The pathogenicity of the B. bassiana conidia produced on the different substrates was evaluated in the coconut termite. The mortality rate of infected termites did not differ statistically, surpassing 80 % mortality, except for the control group. The enzymatic activity (cellulolytic and amylolytic) was determined by the DNS method (dinitrosalicylic acid). The substrates used in the solid state fermentation, malt A (1.178 ± 0.002 U/mL), malt B (2.392 ± 0.013 U/mL), algaroba fiber (0.596 ± 0.007 U/mL) and acerola seed (0.964 ± 0.09 U/mL) showed amylolytic activity. From this analysis, different temperatures (30°, 40º, 50º, 60º, 65º, and 70º C) were evaluated to identify the optimum temperature of the amylolytic enzymes produced in this process. It was observed that the greatest activities found were in extreme temperatures, in the range of 60º to 70º C, suggesting that these enzymes are thermophilic. Sugarcane bagasse presented higher cellulolytic activity (15.29 ± 0.07 U/mL) for CMcase and (2.58 ± 0.9 U/mL U/mL) for FPase due to the characteristic of its cellulosic matrix, which differs from the other substrates. Proteolytic activity was quantified using azocasein. The algaroba had the highest activity (0.514 ± 0.009 U / mL). The alternative substrates used for growth and sporulation of B. bassiana can provide a reduction of approximately 50 % in the cost of producing conidia of entomopathogenic fungi used in the biological control of several insect pests. In addition, they are presented as a viable alternative for the production of microbial enzymes with wide application in several biotechnological processes. / Beauveria bassiana é um fungo entomopatogênico usado no controle biológico de insetos-praga na agropecuária. Os custos de produção de seus conídios, em larga escala, no substrato padrão (arroz) utilizado atualmente onera o processo de produção. Encontrar alternativas como forma de minimizar os custos do processo, levou a necessidade de averiguar a eficiência de substratos alternativos que, além de propriedades nutricionais importantes, possuem grande disponibilidade e baixo custo. Os fungos entomopatogênicos produzem enzimas que estão envolvidas no processo de patogenicidade e virulência. Porém, ao serem estimulados por substratos específicos podem produzir enzimas de interesse biotecnológico. Dessa forma, o objetivo deste trabalho foi analisar o potencial de diferentes substratos (fibra da algaroba, resíduos de malte, sementes e fibras de acerola e bagaço da cana-de-açúcar) para conidiogênese e produção enzimática (fermentação em estado sólido) a partir de B. bassiana. Os experimentos para produção e viabilidade dos conídios foram realizados em triplicata, em erlernmeyer (250 mL) contendo 30 g de cada substrato, 0,3 μL da suspensão de conídios (1 x 106 conídios/mL), umidade de 70 ± 10% e temperatura (T = 29 ± 1° C). Após 10 dias de incubação, os substratos arroz (meio padrão) (2,00 x 106 conídios/g de substrato), malte A (1,22 x 106 conídios/g), malte B (1,75 x 106 conídios/g) e fibra de algaroba (2,36 x 106 conídios/g), proporcionaram maior produção de conídios. A viabilidade dos conídios produzidos nesses mesmos substratos não diferiu estatisticamente entre si, com porcentagem de germinação de 99,96; 90,04; 93,17 e 98,21 %, respectivamente. A patogenicidade dos conídios de B. bassiana produzidos nos diferentes substratos foi avaliada no cupim do coqueiro. A taxa de mortalidade dos cupins infectados não diferiu estatisticamente superando 80 % de mortalidade com exceção do grupo controle. A atividade enzimática (celulolítica, amilolítica) foi determinada pelo método DNS (ácido dinitrosalicílico). Os substratos utilizados na fermentação em estado sólido, malte A (1,178 ± 0,002 U/mL), malte B (2,392 ± 0,013 U/mL), fibra algaroba (0,596 ± 0,007 U/mL) e semente de acerola (0,964 ± 0,09 U/mL) apresentaram atividade amilolítica. A partir dessa análise, diferentes temperaturas foram avaliadas (30°, 40º, 50º, 60º, 65º e 70º C) para identificar a temperatura ótima das enzimas amilolíticas produzidas nesse processo. Observou-se que as maiores atividades encontradas foram em temperaturas extremas, na faixa de 60º a 70ºC, sugerindo que essas enzimas são termofílicas. O bagaço de cana de açúcar apresentou maior atividade celulolítica (15,29 ± 0,07 U/mL) para CMcase e (2,58 ± 0,9 U/mL) para FPase devido à característica de sua matriz celulósica, que difere dos demais substratos. A atividade proteolítica foi quantificada utilizando a azocaseína. A algaroba apresentou a maior atividade (0,514 ± 0,009 U/mL). Os substratos alternativos utilizados para crescimento e esporulação de B. bassiana podem fornecer uma redução de aproximadamente 50 % nos custos de produção de conídios de fungos entomopatogênicos utilizados no controle biológico de vários insetos-praga. Além disso, apresentam-se como alternativa viável para a produção de enzimas microbianas com aplicação ampla em diversos processos biotecnológicos.

No description available.