Orientador: Ranulfo Monte Alegre / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-07-25T00:32:50Z (GMT). No. of bitstreams: 1 Rizzatto_MarciaLuzia_M.pdf: 2359270 bytes, checksum: 5478fd798a0355f913b6d8f29070ea82 (MD5) Previous issue date: 1999 / Resumo: No presente trabalho, estudou-se a produção e produtividade de pectinase por Penicillium italicum IZ 1584 e por Aspergillus niger NRRL 3122 através de fermentação semi-sólida de bagaço de laranja industrialmente processado, em embalagens de polipropileno. Foram feitos ensaios com bagaço de laranja lavado e não lavado. A produção de pectinases com bagaço lavado iniciou-se mais cedo, porém os valores de atividade obtidos com o bagaço não lavado foram maiores para os dois microrganismos, sendo os valores da atividade do P. italicum IZ 1584 (15,1 UIlgMFU) maiores que os do A. niger NRRL 3122 (9,56 UIlgMFU). Em ensaios utilizando bagaço de laranja lavado adicionado de açúcares sacarose, glicose ou frutose, observou-se atividade máxima no meio com sacarose (15,02 UIlgMFU), para o P. italicum IZ 1584, enquanto que os meios com glicose e frutose apresentaram valores próximos de atividade 6,88 UIlgMFU e 6,94 UI/g 1\.1FU, mas menores comparados com o meio com sacarose. O fungo A. niger NRRL 3122 produziu pouca atividade de pectinase nos meios aos quais foram adicionados os açúcares. A atividade máxima foi obtida em meio com glicose (1,98 UI/gMFU), valor próximo do meio com frutose (1,55 UIlgMFU) e o meio com sacarose foi o que apresentou o menor valor de atividade (1,1 UIlgMFU). O fungo P. italicum IZ 1584 mostrou-se mais adequado para a produção de pectinase nos meios de fermentação testados. A produção de pectinase por P. italicum IZ 1584 foi 37% maior que a produção por A. niger NRRL 3122 em bagaço não lavado, 40% em bagaço lavado, 93% em meio com sacarose, 28,8% em meio com glicose e 77,7% em meio com frutose. Em fermentação utilizando misturas de bagaço lavado e não lavado em diferentes proporções, os maiores valores de atividade de pectinase também foram obtidos com o fungo P. italicum IZ 1584. O valor máximo de atividade de pectinase obtido (20,72 UIlgMFU), foi com o meio com 75% de bagaço lavado e 25% de bagaço não lavado, sendo este valor, o maior encontrado neste trabalho / Abstract: The objective of this experimental work was to study the pectinase production and productivity by Penici/lium italicum IZ 1584 and Aspergillus niger NRRL 3122, through solid-state fermentation in a medium containing processed orange bagasse as substrate, in flexible polypropilen packs. The initial experiments studied the medium composed by washed orange bagasse and no washed bagasse as source of carbono The pectinases production with washed bagasse began earlier, however the activity values obtained with no washed bagasse were bigger for the two microorganisms 15.1 UIlgMFU and 9,56 UIlgMFU, respectively, P. italicum IZ 1584 and A. niger NRRL 3122. In the experiments using washed orange bagasse supplemented with sugars (sucrose, glucose or fiutose), a maximum activity was observed in the medium with sucrose (15.02 UIlg MFU) for the P. italicum IZ 1584, while the media with glucose or fiutose presented close values of activity of 6.88 UIlgMFU and 6.94 UIlgMFU, respectively, but they were smaller when compared with the medium with sucrose. The fungus A. niger NRRL 3122 produced small pectinase activity in the media where sugars were added. The maximum activity was obtained in the medium with glucose (1,98 UIlgMFU), with similar value for the medium with fiutose (1.55 UIlgMFU). The medium with sucrose (1.1UI1gMFU), presented the smallest activity value. The fungus P. italicum IZ 1584 showed best pectinase production in the tested fermentation media. The pectinase production by P. italicum IZ 1584 was 370,10 superior to the A. niger NRRL 3122 on no washed bagas se, 40% on washed bagasse, 93% on the medium with sucrose, 28.8% on the medium with glucose and 77% on the medium with frutose. In fermentation using mixtures of washed bagasse and no washed bagasse in different proportions, the biggest values of pectinase activity were also obtained with the fungusP. italicum IZ 1584. The maximum value ofactivity (20.72UI/gMFU) was obtained on a medium with 75% washed bagasse and 25% no washed bagasse. This value was the maximum found in this work / Mestrado / Mestre em Engenharia de Alimentos

Orientador: João Lucio de Azevedo / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-25T15:34:04Z (GMT). No. of bitstreams: 1 Martens_IngridSchmidt-Hebbel_D.pdf: 7343296 bytes, checksum: 4ce47b2ce62b55b5bca6954dc4e9d09c (MD5) Previous issue date: 1999 / Doutorado

Fructooligosaccharides (FOS) are short-chain fructans with a terminal glucose moiety and are found naturally in many plant species. Besides their wide use as an alternative sweetener in food and beverage industry, FOS have shown great potential as neutraceuticals against diabetes, colon cancer and bowel disease. The uses of FOS are dependent on the degree of polymerisation that they exhibit. β-fructofuranosidase (FFase) and fructosyltransferase (FTase) enzymes are capable of synthesing FOS from carbohydrate raw materials such as chicory and sugar beet. The aim of this study was to investigate the synthesis of FOS of a pre-defined chain length, from sucrose, by the enzyme FopAp; a β-fructofuranosidase from Aspergillus niger. ATCC 20611. The crude enzyme FopAp was successfully purified, with a yield of 78.20 %, by ammonium sulphate precipitation and anion exchange chromatography. Two protein fractions, named FA and FB were shown to exhibit FFase activity. SDS PAGE analysis revealed two proteins with molecular weights of 112 kDa and 78 kDa, which were identified as a FFase and a hydrolase. Temperature and pH optima of 20 ºC and 9, respectively, were observed for the transfructosylation activity in the FFase. The purified FFase exhibited a half life of 1.5 hrs under optimal conditions. Substrate kinetic studies indicated a high hydrolytic activity at low sucrose concentrations, with Vmax and Km of 1.25 μmol/ml/min and 3.28 mM, respectively. Analysis by response surface methodology identified temperature and pH to be significant factors for the production of kestose and nystose, at a 95 % level of confidence. These findings were confirmed by neural networks constructed to identify optimal conditions of FOS synthesis.FOS synthesis was found to be optimal between pH 6 and pH 9 at 25 ºC. The factor of reaction time was found to be insignificant within the selected experimental constraints, for both FOS species. The findings of this investigation are very important as the foundations of a commercially viable synthetic process for the production of FOS.

Recent data on the effect of trace elements on the production of citric acid by Aspergillus niger 72-4 suggested that at last a firm basis had been established for studies on the mechanism of production. Citric acid production is an important commercial process and most research had been directed toward obtaining high yields of the acid. The small amount of information on mechanisms is invalidated by the new knowledge of the importance of trace minerals in citric acid synthesis. The attempt at elucidating a system was approached by studying the distribution of organic phosphates in the mats and by manometric experiments. By using the Umbreit fractionation method combined with chromatographic analysis none of the phosphorylated intermediates present in the Embden-Meyerhof system could be identified. Evidence for a pentose and a ketose phosphate is presented. The manometric studies on still cultures were unsatisfactory due to a high endogenous rate and to difficulties in handling the mat. Shake cultures grown for four days and then depleted for 24 hours in the medium minus sucrose and manganese were shown to be a workable method for manometric studies. Using this method evidence for the presence of most of the enzymes required for the oxidation of the Krebs cycle intermediates is presented. A survey of the literature on cell preparations was made. Attempts to prepare active cell preparations failed since enzyme activity seems to be associated with the structural integrity of the mycelium. / Land and Food Systems, Faculty of / Graduate

Orientador : Renato Bonatelli Junior / Dissertação (mestrado) - Universidade Estadual de Campinas. Instituto de Biologia / Made available in DSpace on 2018-07-17T01:59:07Z (GMT). No. of bitstreams: 1 Vialta_Airton_M.pdf: 5894822 bytes, checksum: 4493787d6f88a9c0cd04c4bbaac32710 (MD5) Previous issue date: 1987 / Resumo: O presente trabalho teve como objetivos principais, verificar a ocorrência do ciclo parassexual em Aspergillus awamori, testar a produção de amiloglicosidase dos derivativos, mutantes e diplóides obtidos e realizar o cruzamento interespecífico com A. niger. Além desses, estudos foram desenvolvidos com a instabilidade apresentada por A. awamori.. A linhagem NRRL 3112 segrega conídios pro e forma setores espontaneamente. Este comportamento não seria o esperado para um clone e sugere a existência de heterozigose para as características estudadas, a qual poderia estar contida numa duplicação parcial ou total de genoma. Mutantes auxotróficos e morfológicos de Á. awamori foram conseguidos utilizando-se os métodos de isolamento total e de enriquecimento por filtração. Este último mostrou freqüências de isolamento 12 vezes maiores. Mutantes resistentes ao Brometo de Etídio também foram isolados, mas somente após indução com luz ultravioleta. Os mutantes foram utilizados em cruzamentos que permitiram verificar a ocorrência do ciclo parassexual. Através da análise dos segregantes, pode ser evidenciada ligação entre os genes etbl, grel bwnl; morl, arg2 e leul, mor2. O gene pabl segregou independentemente e, assim, foi possível sugerir 4 como o numero mínimo de grupos de ligação nessa espécie. Entre os critérios não geneticos utilizados na caracterização, o diâmetro de conídios e o tratamento com Benlate mostraram-se eficientes para separar haplóides de diplóides. O método de extração e quantificação de DNA por núcleo também foi adequado para esse fim. Com relação ã enzima, o primeiro passo foi averiguar se o método empregado estava medindo a atividade da amiloglicosidase, fato que foi confirmado fazendo o teste com o inibidor e a dextrina limite. Foi constatada uma relação inversamente proporcional entre a porcentagem de segregação de conídios pro e a produção de amiloglicosidase. Só foi possível obter o cruzamento entre A. awamori e Á. niger através de fu são de protoplastos. A freqüência de formação de colônias prototróficas foi relativamente baixa, situando-se na faixa de 0,6%, possivelmente devido ao pequeno número de protoplastos utilizados para a fusão e a um provável efeito tóxico diferencial do agente fusogênico utilizado. As colônias prototróficas isoladas inicialmente puderam ser classificadas como heterocarióticas. A partir destas, o produto de fusão híbrido foi obtido na forma de setores que exibiam complementação entre as marcas genéticas das parentais. Através da análise do híbrido, pode ser evidenciada ligação entre os genes nicl, 0lv2, bwnl, amy, pro. Houve distribuição ao acaso dos grupos de ligação, semelhante ao esperado para um diplóide intra - específico sugerindo alto grau de homologia cromossômica entre as duas espécies. Os mesmos critérios de caracterização utilizados com sucesso para separar linhagens haplóides de diplóides. nos cruzamentos intra-específicos foram adotados e também nesse caso mostraram resultados satisfatórios / Abstract: The present work with Aspergillus was done aiming to study the following: 1- Occurrence of the parasexual cycle;2- Occurrence of interspecific hybridization with A. niger.3- Amyloglucosidase production of the parental and derived strains, including auxotrophic mutants, diploids and the interspecific hybrid. During the first stage of the work, it was observed that the NRRL 3112 strain of A. awamori is unstable because it spontaneously segregates pro conidia (deficient for proline synthesis) and produces sectors. The last characteristic is also observed in pro derivatives and it was supposed that it is independent from pro conidia segregation. These characteristics are not expected from a clone and together with other evidences (Benlate segregation, differential susceptibility to acetone, variation in number of nuclei per conidia and conidial diameter), it was suggested that there is a partial or total duplication of the genome. Auxotrophic and morphological mutants of A. awamori were induced by ultraviolet light and selected by using total isolation and filtration enrichment methods. An increase of 12 times in the mutant frequency was observed when the last method was employed. Ethidium bromide resistant mutants were also isolated only after ultraviolet induction. Diploid strains were readily obtained and could easily be' separated from haploid strains by conidia diameter, Benlate segregation and nuclear DNA content. Segregation analysis indicated linkage between etb1 gre1 bwn1, mor1, arg1 and leu1, mor2. Because pab1 marker segregated independently from all others it was suggested at least 4 linkage groups for A. awamori. Only heterokaryotic colonies were detected when A. awamori and A. niger protoplasts were fused and plated in selective medium. The low frequency (0,6%) and the heterokaryotic nature of the colonies could probably be attributed to: 1) low protoplasts number and 2) toxic effect to the fusogenic agent to A. niger protoplasts. Hybrid colonies were isolated after several transfers in selective medium. The hybrid nature of these colonies was established by the same criteria used in the intraspecies crossing. Segregation analysis indicated a high level of chromosomal homology between the 2 species and it was possible to suggest linkage between nic1 olv2 genes of niger and bwn, amy, pro of awamori. As it was evident from the use of limit dextrin and a specific inhibitor. glucoamylase is the main enzyme activity detected by the usual assay procedure. It has also been detected that high. frequency of pro conidia in A. awamori is correlated with the low level of enzyme production / Mestrado / Mestre em Genetica

A première vue, la poterie est une activité qui se pratique seule :la potière possède son propre atelier dans le village et est l’unique bénéficiaire de la vente de ses récipients. Néanmoins les enquêtes de terrain menées dans l’Arewa et le Kurfey oriental (Niger) révèlent qu’à chaque étape de la chaîne opératoire, l’artisane est en contact, plus ou moins proche, avec d’autres praticiennes (apprenties, artisanes de la localité ou d’autres localités). Ces contacts, organisés ou informels, prennent généralement place dans le contexte de certaines étapes de la chaîne opératoire à deux échelles d’analyse différentes :l’échelle villageoise par l’occupation d’un atelier et/ou d’un site de cuisson commun à divers artisanes et l’échelle extra villageoise par la fréquentation de sites d’extraction et de marchés partagés par des artisanes issues de localités différentes. Autant d’espaces de pratiques fréquentés par les potières susceptibles d’échanger leurs savoirs, collaborer et construire, ensemble, un répertoire de connaissances mobilisables. Quand une potière réalise son récipient, elle inscrit sa pratique dans un monde connu et habité. Sa technique est autant marquée par son apprentissage que par son identité familiale et villageoise ainsi que par ses interactions avec d’autres artisanes. Si on admet que chaque pratique est située et que la situation donne du sens à la pratique, il devient impératif d’examiner les situations de partage des savoirs ainsi que les cadres dans lesquels ces situations prennent place. Nous mettrons en évidence les points de contacts qui lient et interconnectent les artisanes d’une même localité et des différentes localités de la zone d’étude. Nous évaluerons les dimensions sociales et relationnelles de l’apprentissage de la poterie ainsi que la façon dont les habiletés sont conceptualisées et investies par les artisanes. En analysant le contexte d’apprentissage et de pratique des artisanes, nous souhaitons apporter un éclairage sur comment s’accroche le social et la technique et ainsi expliquer les configurations techniques observées au sein de la région d’étude. <p> / Doctorat en Histoire, art et archéologie / info:eu-repo/semantics/nonPublished

A model for the explanation of socioeconomic change in West Africa is presented, and tested with data from Zinder province, Niger Republic. A Marxist social formation analysis provides a model of change and continuity in peripheral, precapitalist modes of production, and of economic causality. A regional marketing systems analysis elaborates on the effects of exchange systems upon production systems and suggests quantitative data by which the Marxist model is tested. Marketing arrangements in Niger are discussed. An analysis of the Nigerien economy is presented. The way French, EEC, and Nigerien government policies have shaped the extraversion, mercantilism, and dependence of the economy is clarified. Then, the manipulation of exchange and production within Niger by state marketing agencies is explored. A regional systems analysis of marketing in Zinder province is carried out, including the system's history since precolonial times. The modern systems are described with price correlations, commodity flows, mobile trader circuits and strategies, and consumer behavior. Marketing and relations of production and reproduction in three communities, an agricultural village, a pottery-producing one, and a handicraft tannery were linked. Variations in household morphology and task performance, in gandu and master-apprentice workshop organization, in specialization in output, and in exchange and distribution of resources are related to the hierarchical position and functions of markets in which each community has participated historically. The key hypothesis was confirmed: local modes of production are now articulated with the modern world system. However, local modes have not been completely transformed from their antecedents. The structure of exchange makes it advantageous for foreign entrepreneurs and the Nigerien government to allow local modes to persist, while decapitalization, and tenacious political and reproductive relationships discourage transformation from below. By adding a regional systems perspective to a social formation analysis, a rich and testable description of the factors both facilitating and impeding changes in articulated modes of production was obtained.

La gestion des aires protégées en Guinée pose le problème de la cohabitation des politiques publiques et des systèmes traditionnels. Censée améliorer la gestion des aires protégées, cette cohabitation s’avère difficile et ne produit pas les résultats escomptés. Pour contribuer à la compréhension de cette difficile cohabitation, cette thèse propose une analyse de l’évolution de la politique de gestion des aires protégées en Guinée, de l’époque précoloniale à nos jours. La démarche utilisée fait appel à plusieurs approches méthodologiques : recueil et analyse de documents historiques et juridiques, recueil et analyses des traditions orales ancestrales relatives à la protection de la nature, observations de terrain, inventaires floristiques, estimations et analyses qualitatives, enquêtes par entretiens semi-directifs. Les résultats obtenus ont permis de retracer et de caractériser les différentes phases de la gestion des aires protégées en Guinée. La gestion des aires protégées précoloniales a connu diverses formes, allant de la sacralisation à la gestion clanique ; elle a varié en fonction des coutumes des populations autochtones de chacune des régions naturelles du pays. Pendant l’époque coloniale, 167 aires protégées ont été mises en place dont 157 forêts classées, 4 parcs de refuge de faune et une réserve naturelle intégrale. A son accession à l’indépendance en 1958, la Guinée a hérité des aires protégées coloniales et a appliqué, jusqu’en 1984, une politique fondée sur la législation forestière de l’administration coloniale. L’Etat s’est approprié les aires protégées dans leur contexte contemporain seulement à partir des années 1984, et a progressivement mis en place de nouveaux dispositifs (législatif et institutionnel) de gestion. Avec l’appui des bailleurs de fonds, il a mis en place plusieurs catégories d’aires protégées (parcs nationaux, réserves de biosphère, aires protégées transfrontalières, zone de conservation) dont la gestion qui se veut participative en associant les populations locales, soufre aujourd’hui essentiellement du manque de financements associé à l’insuffisance de la logistique nécessaire à une gestion opérationnelle et efficace. L’étude du cas du Parc National du Haut Niger révèle que, malgré la reconnaissance et la prise en compte du rôle des communautés traditionnelles (Waton), les populations locales adhèrent à la gestion participative sans grande conviction. Les structures publiques associées à cette gestion ne disposent pas de moyens suffisants pour intervenir de manière efficiente. L’exemple du PHNN illustre l’écart entre le discours dominant qui prône la gestion intégrée des aires protégées et les difficultés de l’Etat à mettre en œuvre une gestion participative. Ces difficultés ne devraient pas pour autant conduire à une remise en cause de la gestion participative, car nos observations et nos enquêtes suggèrent que la stratégie peut fonctionner et faire la preuve de son efficacité si des efforts sont entrepris dans l’appui au développement communautaire et dans la création d’activités génératrices de revenus pour les populations traditionnelles qui mettent leurs savoirs au service de la gestion des aires protégées. / Management of protected areas in Guinea is the problem of the coexistence of public policy and traditional systems. To contribute to the understanding of this difficult cohabitation, this thesis proposes an analysis of the evolution of policy management of protected areas in Guinea, from precolonial times to the present. The approach involves several methodological approaches. The results were used to trace and characterize the different phases of the management of protected areas in Guinea. The state has appropriated the protected areas in their contemporary context only from year 1984. The example of PHNN illustrates the difference between the dominant discourse advocating the integrated management of protected areas and the difficulties of the state to implement a participatory management. Our observations and surveys suggest that the strategy of management override implementation can work if efforts are in supporting community development.

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