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An investigation into the hex1 gene and gene promoter for the enhancement of protein production in Trichoderma reesei / Investigation into the hex1 gene and gene promoter in Trichoderma reeseiCurach, Natalie Claire January 2005 (has links)
Supplementary material to figures contained on DVD only available with manuscript. / Thesis (PhD)--Macquarie University, Division of Environmental & Life Sciences, Dept. of Biological Sciences, 2005. / Bibliography: p. 221-244. / Introduction -- Materials and methods -- Isolation of the hex1 gene from Trichoderma reesei and Ophiostoma floccosum -- Expression of DsRed under the cbh1 promoter and the hex1 promoter with random integration -- Modified expression vectors containing a fusion to a portion of hex1 gene sequence -- Expression of DsRed from the hex1 locus and the phenotypic characteristics of a hex1 deletion mutant -- Summary and concluding discussion. / For Trichoderma reesei to be developed as an effiecient producer of a large variety of proteins, the expression system requires diversification. In particular, the choice of promoters available needs to be broadened to include promoters which are active in conditions other than those conducive to induction of cellulase expression. Using proteomics, the HEX1 protein was identified as an abundant protein of the cell envelope of T. reesei when grown on a range of carbon sources, suggesting that a strong constitutive promoter drives the expression of this physiologically important protein. This thesis is an exploration into the hex1 gene promoter and the role of hex1 in the maintenance of mycelium integrity in T. reesei with consideration for the application of this gene in the further development of filamentous fungi as protein expression systems. -- The single copy hex1 gene and flanking regions were isolated from T. reesei and another biotechnologically important fungus, Ophiostoma floccosum. The fluorescent reporter protein DsRed1-E5 was expressed under the T. reesei hex1 promoter and promoter activity was monitored by fluorescence CLSM and RNA analysis. During the rapid growth phase of a culture, the hex1 promoter was active in a range of carbon sources and three transcipt types with alternative tsp and splicing sites were discovered for the hex1 gene. The distribution of fluorescence throughout the mycelium suggested spatial regulation of the hex1 promoter as well as temporal regulation. The promoter was continually active in the absence of a functional hex1 gene product suggesting that the hex1 promoter is regulated in part, by negative feedback from the endogenous gene product. Interruption of the hex1 gene produced hyphae that leaked excessive volumes of cytoplasm when physically damaged which may be advantageous for the externalisation of selected protein products. The results indicate that the regulation of the hex1 hene promoter is complex and that the hex1 gene is integral to the maintenance of the integrity of the fungal mycelium. / Mode of access: World Wide Web. / xv, 244 p. ill
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Proteomic analysis of the biological control fungus TrichodermaGrinyer, Jasmine January 2007 (has links)
Thesis by publication. / "August 2006" / Thesis (PhD)--Macquarie University, Division of Environmental & Life Sciences, Dept. of Biological Sciences & Dept. of Chemistry & Biomolecular Sciences), 2007. / Bibliography: leaves 157-183. / 1. Introduction -- 1.1. Proteomics and two-dimensional electrophoresis -- 1.2. A proteomic approach to study the filamentous fungus Trichoderma -- 1.3. Aims of the thesis -- 2. Materials and methods -- 3. Results and discussion -- 3.1. Method development for the display and identification of fungal proteins by 2DE and mass spectrometry -- 3.2. Discovery of novel determinants in the biological control of phytopathogens by Trichoderma atroviride -- 3.3. Summary and concluding remarks. / Trichoderma harzianum and T. atroviride are filamentous fungi commonly found in soil. Both display biocontrol capabilities against a range of phytopathogenic fungi including Rhizoctonia solani and Botrytis cinerea which are known pests of hundreds of commercially important crops including tomatoes, potatoes, beans, cucumber, strawberries, cotton and grapes. These Trichoderma species secrete a combination of enzymes degrading cell walls and antibiotics to overgrow and kill fungal phytopathogens. They are seen as an environmentally friendly alternative to chemical fungicides currengly used on crops. / A proteomic approach was taken to separate and identify proteins from a strain of T. harzianum with well established biocontrol properties. Several methods were developed in this thesis to display the whole proteome content and several subcellular proteome fractions from T. harzianum. Proteins were separated by two-dimensional electrophoresis and identified by mass spectrometric methods. The resulting proteomic maps represent the first extensive array of cellular and sub-cellular proteomes for T. harzianum. / Cellular protein patterns of T. atroviride (T. harzianum P1) grown on media containing either glucose or R. solani cell walls were compared by differential gel electrophoresis to identify a suite of new proteins involved in the biological control response. Twenty four T. atroviride protein spots up-regulated in the presence of the R. solani cell walls were identified by mass spectrometry and N-terminal sequencing. Proteins identified from this study included previously implicated enzymes degrading cell walls and three novel proteases, vacuolar serine protease, vacuolar protease A and trypsin-like protease. The genes encoding two of these proteases, vacuolar protease A and vacuolar serine protease have been cloned by degenerate primer PCR and genomic walking PCR and sequenced. The gene sequences and protein sequences derived from these genes have been partially characterised. / Mode of access: World Wide Web. / 194 leaves ill
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Developing Ophiostoma floccosum as a novel expression systemWu, Caiyan January 2007 (has links)
"This thesis is based on the following articles, referred to in the text by the Roman numerals given below. In addition some unpublished results are presented. I. Caiyan Wu ... [et al] Improvement of the secretion of extracellular proteins and isolation and characterization of the amylase I (amyI) gene from Ophiostoma floccosum [pub. in ] Gene 384: 96-103 -- II. Caiyan Wu ... [et al.] Activity-based identification of secreted serine proteases of the filamentous fungus Ophiostoma. Accepted by Biotechnology letters DOI 10.1007/s10529-007-9333-6 -- III. Caiyan Wu ...[et al.] Expression of a thermostable bacterial xylanase in the filamentous fungus Ophiostoma floccosum. Submitted to Letters in applied microbiology in July 2007." - leaf 9. / Thesis (PhD)--Macquarie University, Division of Environmental and Life Sciences, Dept. of Chemistry & Biomolecular Sciences, 2007. / Bibliography: leaves 100-123. / Introduction -- Materials and methods -- Results and discussion -- Conclusion and future aspects -- References -- Publications I, II and III. / Ophiostoma spp. belong to the Ophiostomataceae family, a large group of ascomycetes, which are the most frequent blue stain fungi isolated from stained wood. Most Ophiostoma species do not compromise the strength properties of wood, but do reduce the aesthetic quality of timber and therefore decrease the economic value of lumber. Some albino variants of O. floccosum and O. piliferum have been used as biological control agents to prevent blue staining. This successful whole organism approach plus the added capability of extracellular protein secretion makes Ophiostoma spp. attractive for industrial application. In addition, Ophiostoma produces only a small range of abundantly secreted proteins in liquid culture, which can facilitate downstream purification of any recombinant gene product introduced into the system. Genes encoding efficiently secreted proteins provide a potential souce for strong promoters for high-level gene expression. These characteristics provide an excellent starting point for the development of a novel expression system. / In this study, UV-mutagenesis was applied to improve protein secretion in Ophiostoma floccosum. Amylase activity was used as an indicator for enhanced protein secretion after repeated rounds of mutagenic treatment. Several mutants of O. floccosum derived by UV mutagenesis were isolated and the total amount of secreted protein was increased by 4 to 6 times. The amylase activity in the culture supernatant of the best mutant (MQ.5.1) was increased by more than 240-fold compared to the initial parental strain. At the same time, the amount of total secreted protein was about six times greater to that of the parental strain. Proteinase profiles in the culture supernatants of several key mutants were characterized for the future matching of an expression host with a particular gene product. N-terminal sequencing of the five dominant proteins separated by SDS-PAGE from the culture supernatant was conducted. Two of the proteins identified were subtilisin-like proteinases and one was a pepsin-like proteinase. In addition, one protein was identified as an_-amylase and one remained unidentified. A 6.5 kb DNA fragment was isolated by Genomic Walking PCR using primers based on the _-amylase amino acid sequence. The amplified fragment contained the entire gene encoding_-amylase (amyl) and its regulatory sequences. Analysis showed that multiple transcripts were generated from the single _-amylase gene locus. / A series of expression vectors containg the _-amylase regulatory sequences and partial amyl gene were constructed. Several selection markers were screened and the hph gene conferring hygromycin resistance under the regulation of the Aspergillus nidulans gpd promoter was chosen and inserted into the amyl expression vectors. The gene encoding a red fluorescent protein DsRed-E5 was used as a reporter gene to test the expression system using mutant MQ.5.1 as host. However, no transformants were obtained by either biolistic transformation or protoplast transformation. Subsequently, an alternative strategy was developed using a thermostable xylanase B as a reporter. Thermostable xylanase activity was detected in the culture supernatants of several transformants. Production of xylanase by transformant SS41 which exhibited high secreted xylanase activity was investigated. Xylanase activity in the culture supernatant of SS41 was visualized by a zymogram gel assay. Two active proteins with molecular masses of around 27 and 30 kDA, which were larger than the predicted Mr of 25 kDA were detected. This is the first report describing successful expression of a recombinant thermostable bacterial enzyme in Ophiostoma. / Mode of access: World Wide Web. / 158 leaves col. ill
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Assimila??o de nitrog?nio e crescimento apical em fungos filamentosos produtores de L-asparaginaseGon?alves, Aline Bacelar 30 September 2016 (has links)
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Previous issue date: 2017 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O tratamento das leucemias ? desafiador por v?rios aspectos, entre os quais podem ser destacados os efeitos adversos e a obten??o de op??es terap?uticas de alta qualidade e de custos razo?veis. A utiliza??o da enzima L-asparaginase como agente terap?utico, limita a fonte ex?gena de asparagina, da qual as c?lulas malignas dependem para o metabolismo celular e para a sobreviv?ncia. Essa ? uma op??o que oferece menores riscos ao paciente e ?s c?lulas sadias, que s?o capazes de sintetizar este amino?cido. Neste cen?rio o objetivo deste trabalho foi selecionar, entre fungos filamentosos, linhagens produtoras da enzima L-asparaginase. O estudo tamb?m buscou avaliar o efeito da varia??o da fonte de carbono e da raz?o carbono-nitrog?nio no crescimento e na express?o da atividade enzim?tica, a fim de desenvolver meios de cultivo para o processo produtivo. Realizou-se tamb?m um estudo do crescimento apical das tr?s linhagens selecionadas, duas do g?nero Penicillium sp. e uma do g?nero Fusarium sp., em diversos meios de cultivo. O conhecimento gerado sobre as linhagens produtoras e os demais estudos realizados permitiram a obten??o de um meio de cultivo que possibilitou a produ??o enzim?tica em at? 11,45 U.min-1.mL-1 com a linhagem de Fusarium sp. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Ci?ncias Farmac?uticas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / The treatment of leukemia is challenging in many ways, including the adverse effects and obtaining treatment options of high quality and reasonable cost. The use of L-asparaginase enzyme as a therapeutic agent limits the exogenous source of asparagine, which the malignant cells depend for cellular metabolism and survival. This option offers lower risk to patients and healthy cells, which are able to synthesize this amino acid. Therefore, the objective of this work was to select among filamentous fungi, producing strains of L-asparaginase enzyme. The study also aimed at evaluating the effect of varying the carbon source and carbon-nitrogen ratio in the growth and expression of the enzymatic activity to develop culture media for the production process. It was also carried out a study of the apical growth of the three strains selected, two of the genus Penicillium sp. and one Fusarium sp., cultivated in various culture media. The knowledge about the growth of the strains studied in different nutritional sources and other studies allowed obtaining a culture medium that enabled the enzyme production of 11.45 U.min-1.mL-1 by Fusarium sp.
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Fungos associados às onicomicoses : prevalência e suscetibilidade a drogas antifúngicasMaifrede, Simone Bravim 06 March 2009 (has links)
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Previous issue date: 2009-03-06 / INTRODUÇÃO: Onicomicose é a infecção da unha causada por amplo espectro de espécies fúngicas, incluindo leveduras e fungos filamentosos dermatófitos e nãodermatófitos.
Devido à variável suscetibilidade dos diversos agentes etiológicos às drogas antifúngicas, o diagnóstico laboratorial vem sendo considerado uma ferramenta importante para se estabelecer a etiologia e auxiliar na escolha do tratamento da onicomicose. Com base na elevada porcentagem de falha terapêutica no tratamento da onicomicose, tem-se evidenciado o interesse na padronização de testes de suscetibilidade in vitro de fungos filamentosos. OBJETIVOS: Estabelecer a freqüência das onicomicoses em relação a outras dermatomicoses; definir a etiologia das onicomicoses através do isolamento e identificação dos fungos; comparar o
padrão de suscetibilidade entre fungos dermatófitos e não-dermatófitos às drogas fluconazol, cetoconazol, itraconazol, miconazol, ciclopirox, terbinafina e griseofulvina. MÉTODOS: As amostras clínicas foram colhidas através de raspagem e/ou
fragmentação da unha e o exame microscópico direto foi realizado através do tratamento destas amostras com hidróxido de potássio (KOH) a 20% e tinta Parker. As culturas foram realizadas nos meios de ágar Sabouraud dextrose adicionado de 0,05 mg.mL-1 de cloranfenicol e ágar Mycose, incubados à temperatura ambiente e por um período de até 15 dias. A identificação dos fungos filamentosos foi baseada
na observação de suas características macroscópicas e microscópicas e os testes de suscetibilidade in vitro a drogas antifúngicas foram baseados no Documento M38-A do CLSI. RESULTADOS: O diagnóstico laboratorial das dermatomicoses foi estabelecido em 69% dos 1.008 pacientes com lesões sugestivas de dermatomicoses encaminhados ao Laboratório de Diagnóstico Micológico do Depto.
de Patologia / UFES, no período de 12/03/2004 a 14/08/2008. Onicomicose foi diagnosticada em 333 pacientes e os grupos de fungos mais isolados foram: leveduras 55,6%, fungos filamentosos não-dermatófitos 27,2% e dermatófitos 17,3%.
Fungos dermatófitos foram mais inibidos in vitro que fungos não-dermatófitos. As drogas fluconazol e griseofulvina inibiram apenas fungos dermatófitos, enquanto a terbinafina foi a droga que mais inibiu os dois grupos de fungos e em baixas
concentrações. A quantificação do inóculo por contagem em hemocitômetro e em placas de ágar Sabouraud revelou que o acerto do inóculo em espectrofotômetro pode ter uma boa correspondência se estabelecido em faixas de transmitância
diferenciadas para os diversos tipos de fungos. CONCLUSÃO: É necessário estabelecer o diagnóstico laboratorial das onicomicoses, já que estas podem ser causadas por diversos agentes etiológicos e com diferentes suscetibilidades in vitro
a várias drogas antifúngicas. / INTRODUCTION: Onychomycosis is the nail infection caused by a wide spectrum of fungi species, including yeasts, dermatophyte and nondermatophyte mould. Due to
the variable susceptibility of the several etiologic agents to the antifungal drugs, the laboratorial diagnosis is being considered an important tool to establish the etiology and to help in the choice of the treatment of onychomycosis. Based on the high percentage of therapeutic flaw in the treatment of onychomycosis, there has been some evident interest in the standardization of the susceptibility tests in vitro of
filamentous fungi. OBJECTIVES: To establish the frequency of the onychomycosis in relation to other dermatomycosis; to define the etiology of the onychomycosis by the isolation and identification of the fungi; to compare the pattern of susceptibility among dermatophytes and nondermatophytes mould to drugs such as fluconazole, cetoconazole, itraconazole, miconazole, ciclopirox, terbinafine and griseofulvine. METHODS: The clinical samples were collected by the scratching and/or fragmentation of the nail and the direct microscopic examination was made by the treatment of these samples with potassium hydroxide (KOH) at 20% and Parker ink. The cultures were made in dextrose agar Sabouraud with 0,05 mg.mL-1 of cloranphenicol and agar Mycosel, incubated to room temperature and for a period
of up to 15 days. The identification of the filamentous fungi was based on the observation of its macroscopic and microscopic characteristics and the tests of susceptibility in vitro to the antifungal drugs were based on CLSI M38-A reference method. RESULTS: The laboratorial diagnosis of the dermatomycosis was established in 69% of the 1.008 patients with lesions that suggested dermatomycosis sent to the Laboratory of Mycologic Diagnosis from the Dept. of Pathology / UFES, in the period of 03/12/2004 to 08/14/2008. Onychomycosis was diagnosed in 333 patients and the groups of more isolated fungi were: yeasts 55,6%, nondermatophyte
mould 27,2% and dermatophytes 17,3%. Dermatophytes were more inhibited in vitro than nondermatophytes ones. Drugs such as fluconazole and griseofulvine inhibited just dermatophytes fungi while terbinafine was the drug which most inhibited both groups of fungi and in low concentrations. The quantification of the inoculum for counting in haemocytometer and in plates of agar Sabouraud revealed that the correctness of the inoculum in espectrofotometer may have established a good correspondence in transmission bands differentiated for the various types of fungi.
CONCLUSION: It is necessary to establish the laboratorial diagnosis of the onychomycosis, as these may be caused by several etiologic agents and with different susceptibilities in vitro to several antifungal drugs.
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Produção de celulases por Gelatoporia subvermispora para hidrólise de material celulósico / Production of cellulases by Gelatoporia subvermispora to cellulosic material hydrolysisReis, Cristiane Bianchi Loureiro dos 16 April 2014 (has links)
Several microorganisms are able of producing enzymes responsible for the conversion of biomass to ethanol, such as cellulases. However, studies about diversity and biotechnological application of microorganisms from Pampa biome are still scarce. To try to reduce this knowledge lack, the Gelatoporia subvermispora fungus was isolated from the Pampa biome, resulting in the first occurrence of this specie in Latin America. Commercially, cellulases are produced by submerged fermentation. However, filamentous fungi that are considered good producers of cellulases show better results in solid-state fermentation, mainly by the similarity between the solid medium and the natural habitat of these microorganisms. In order to evaluate the biotechnological potential of the fungi G. subvermispora for cellulases production, rice straw, sewage sludge and sugar cane bagasse were used as substrate. The highest values for the total cellulolytic activity by the method of filter paper (FP) were obtained using sugarcane bagasse as substrate, reaching the value of 3.82 FPU.g-1. The sewage sludge was an excellent medium for the production of xylanase and exo-cellulases, reaching peak activity of 227.97 U.g-1 and 134.25 U.g-1, respectively. The endo-cellulase activity was similar in almost whole substrates tested, as showed in the runs 11 for rice straw (40.75 U.g-1) and 14 for sewage sludge (35.32 U.g-1). Subsequently, cellulolytic enzymes from fungal Gelatoporia subvermispora produced by solid-state fermentation using different substrates were applied to hydrolyze non-treated sugarcane bagasse using indirect sonication. The best results were obtained using sewage sludge as substrate for enzyme production. The mean yields obtained with enzymes produced using sewage sludge, sugarcane bagasse and rice straw as substrates were 72.8, 58.7 and 51.2 g.kg-1, respectively. Regarding the use of ultrasound to carry out enzymatic reactions, the oscillation amplitude presented a negative effect on yield, whereas pulse factor showed to be benefic for the reactions. / Diversos microrganismos são capazes de produzir enzimas responsáveis pela conversão da biomassa em etanol, tais como as celulases, porém, estudos sobre a diversidade e aplicação biotecnológica dos microrganismos do bioma Pampa ainda são escassos. Para tentar reduzir essa lacuna de conhecimento, o fungo Gelatoporia subvermispora foi isolado do bioma Pampa, resultando na primeira ocorrência dessa espécie para a América Latina. Comercialmente, as celulases são produzidas através de fermentação submersa. Entretanto, fungos filamentosos que são considerados bons produtores de celulases apresentam melhores resultados em fermentação em estado sólido. Para avaliar o potencial biotecnológico do fungo G. subvermispora de produzir celulases os resíduos palha de arroz, lodo de esgoto e bagaço de cana foram utilizados como substrato. Os maiores valores de atividade celulolítica total determinados pelo método de papel filtro (PF) foram obtidos utilizando bagaço de cana como substrato, apresentando 3.82 FPU.g-1. O lodo de esgoto foi um excelente meio para a produção de xilanases e exo-celulases, atingindo valores máximos de 227.97 U.g-1 e 134.25 U.g-1, respectivamente. A atividade da endo-celulase foi similar nos substratos testados, como verificado na condição 11 para a palha de arroz (40.75 U.g-1) e 14 para o lodo de esgoto (35.32 U.g-1). As enzimas celulolíticas produzidas pelo fungo Gelatoporia subvermispora foram aplicadas na hidrólise do bagaço de cana por meio de sonicação indireta. Os melhores resultados foram obtidos utilizando o lodo de esgoto como substrato para a produção das enzimas. Os rendimentos médios de hidrólise obtidos através da produção de enzimas utilizando lodo de esgoto, bagaço de cana e palha de arroz como substrato foram 72.8, 58.7 e 51.2 g.kg-1, respectivamente. Com relação à utilização do ultrassom para as reações enzimáticas, a amplitude apresentou um efeito negativo no rendimento, enquanto o fator pulso foi benéfico para as reações.
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INVESTIGAÇÃO DA DETERIORAÇÃO FÚNGICA DE EMPANADOS CONGELADOS DE FRANGO: ORIGEM DA CONTAMINAÇÃO E RESISTÊNCIA TÉRMICA DOS DETERIORANTES / RESEARCH OF FUNGAL SPOILAGE IN FROZEN CHICKEN NUGGETS: ORIGIN OF THE CONTAMINATION AND THERMAL RESISTANCE OF THE FUNGIWigmann, évelin Francine 29 January 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The food industry has changed in recent decades the focus of the production, since the eating habits of consumers have been directed to practical, fast and tasty foods. So, breaded frozen chicken were created, one of the biggest hits of the fast food industry. This class of pre-made and frozen products allows for long-term storage and can select species of microorganisms capable of growing in low temperatures, especially filamentous psychrophilic fungi. Despite annual losses are estimated at 1 to 1.5 % by fungal spoilage of frozen chicken nuggets, rare are the available scientific data. The objective of this study was to conduct a general mycological investigation of a processing industry of frozen chicken nuggets, analyzing the raw materials, the products in different processing steps and the ambient air of each unit of operation. It was also analyzed the effect of heating treatments applied in the manufacture of the nugget on inactivation of Penicillium commune (NGT 16/12), Penicillium polonicum (NGT NGT 23/12 and 33/12), Penicillium glabrum (NGT 29/12 and NGT 35/12), Penicillium solitum (NGT 30/12) and Penicillium crustosum (NGT 51/12), main species related to deterioration of these products. The flour exhibited counts between 101 and 104 CFU/mL, predominating species P. polonicum, Aspergillus flavus, Aspergillus candidus, Penicillium citrinum and Eurotium amstelodami. The following processed samples showed a steady reduction in scores for 101 CFU/g, with a predominance of P. polonicum. In the other hand, regarding the samples of final product analyzed, 10% were contaminated by P. glabrum, with was also the most predominant species of spoilers in the air environment. The results show that the P. polonicum (NGT 23/12), P. commune (NGT 16/12), P. solitum (NGT 30/12) and P crustosum (NGT 51/12) were able to survive to the heat treatments applied (fried by immersion in oil at 195-200 °C for 6 seconds), and baking in oven at 120-130 °C until the internal temperature reached 70 °C when inoculated in the frozen chicken nuggets. Additionally, it was observed that P. polonicum (NGT 23/12), was the most heat resistant species, recovering counts of 104 CFU/g after frying for 6 minutes and 30 seconds of cooking, having 2,02 log CFU/g reduced at 72 °C and 3,29 log CFU/g reduced at 78 °C in the internal of the product during the baking. According to the results it was observed that both the flour used to manufacture breaded as the air industry environment pose a hazard, then strategies must be taken to reduce the presence of fungal spores in this points, possible sources of these fungal contamination. / A indústria de alimentos tem modificado nas últimas décadas o foco de produção, uma vez que os hábitos alimentares dos consumidores foram alterados, em busca de alimentos práticos, rápidos e saborosos. Logo, foram criados os empanados congelados de frango, um dos maiores sucessos da indústria de fast food. Esta classe de produtos pré-prontos e congelados permite a armazenagem por longos períodos o que seleciona espécies de micro-organismos capazes de se desenvolver em condições de baixas temperaturas, com destaque para os fungos filamentosos psicrófilos. Apesar das perdas anuais serem estimadas em 1 a 1,5 % por deterioração fúngica de empanados congelados de frango, raros são os dados científicos disponíveis. O objetivo deste estudo foi realizar uma investigação micológica geral de uma indústria processadora de empanados congelados de frango, analisando as matérias-primas, os produtos originados e o ar ambiente de processamento. Assim como, o efeito dos tratamentos térmicos aplicados na fabricação dos empanados sob Penicillium commune (NGT 16/12), Penicillium polonicum (NGT 23/12 e NGT 33/12), Penicillium glabrum (NGT 29/12 e NGT 35/12), Penicillium solitum (NGT 30/12) e Penicillium crustosum (NGT 51/12), principais espécies relacionadas a deterioração destes produtos. As amostras de farinha apresentaram contagens entre 101 e 104 UFC/mL, predominando as espécies de P. polonicum, Aspergillus flavus, Aspergillus candidus, Eurotium amstelodami e Penicillium citrinum. As amostras seguintes ao processamento apresentaram uma constante redução nas contagens para 101 UFC/g, com predominância de P. polonicum. Já nas amostras analisadas do produto final, 10% apresentaram contaminação por P. glabrum, espécie também predominante no ar ambiente da fábrica. Os resultados demonstraram que o P. commune (NGT 16/12), P. polonicum (NGT 23/12), P. solitum (NGT 30/12) e P. crustosum (NGT 51/12) são capazes de sobreviver aos tratamentos térmicos aplicados (fritura por imersão com óleo a 195-200 °C por 6 segundos) e cozimento em forno à 120-130 °C até alcançar a temperatura interna de 70 °C, quando inoculados nos empanados congelados de frango. Adicionalmente, foi verificado que o P. polonicum (NGT 23/12), espécie mais resistente aos tratamentos, manteve-se estável com média de contagem fúngica de 104 UFC/g desde a fritura até 6 minutos e 30 segundos de assamento, tendo 2,02 log UFC/g de redução com 72 °C e 3,29 log UFC/g de redução com 78 °C no interior do produto durante o assamento. De acordo com os resultados apresentados foi observado que tanto as farinhas utilizadas na fabricação dos empanados quanto o ar ambiente da indústria representam um perigo de contaminação, assim como foi verificado a sobrevivência de algumas das principais espécies deteriorantes de empanados aos tratamentos térmicos aplicados na indústria, logo estratégias devem ser adotadas para a redução de esporos fúngicos em possíveis fontes de contaminação e a necessidade de novas adequações dos tratamentos para eliminação de fungos filamentosos.
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Influência da fonte de carbono na produção de fruto-oligossacarídeos, na composição da parede celular e na expressão de genes relacionados à sua biossíntese em Fusarium solani (Mart) Sacc. e Neocosmospora vasinfecta E. F. Sm / Effect of carbon source on the production of fructooligosaccharides, in the cell wall composition and expression of genes related to the biosynthesis Fusarium solani (Mart) Sacc. and Neocosmospora vasinfecta E. F. Sm.Galvão, Daiane Felberg Antunes, 1978- 26 August 2018 (has links)
Orientadores: Marcia Regina Braga, Marcia Maria Camargo de Morais / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T04:21:10Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014 / Resumo: Fruto-oligossacarídeos (FOS) são frutanos de baixo peso molecular produzidos por microorganismos. O interesse em FOS vem aumentando uma vez que eles são considerados ingredientes funcionais benéficos à saúde humana. Com o objetivo de analisar como a produção de FOS e a composição da parede celular de fungos filamentosos é afetada pela fonte de carbono, os fungos Fusarium solani (URM 3338) e Neocosmospora vasinfecta (URM 3329) foram cultivados em meios contendo cinco fontes de carbono diferentes (sacarose, inulina, glucose, frutose ou glucose mais frutose, todos a 1%) e coletas foram realizadas aos 5, 10 e 15 dias de crescimento. A partir do meio de cultivo filtrado foram analisados o pH, teores de açúcar total, açúcares redutores e proteínas, a presença de FOS e atividades enzimáticas invertásica e inulinásica. A partir do micélio, a biomassa foi quantificada e a parede celular foi isolada e sua composição em açúcares neutros, ácidos urônicos e quitina analisada. Foi avaliada também a expressão relativa de genes de síntese de parede celular b-1,3-glucano sintase e quitina sintases. Os dois fungos utilizaram todas as fontes de carbono crescendo nas diferentes condições. Atividade de hidrólise foi detectada no meio contendo sacarose ou inulina para o fungo F. solani, gerando glucose, frutose e fruto-oligossacarideos como produtos havendo utilização dos monossacarídeos. O micélio deste fungo apresentou alterações visíveis no crescimento em meio sólido apenas no meio com frutose, mas foi observada igual quantidade de quitina da parede celular deste fungo quando crescido por cinco dias em sacarose e inulina, mas em menor quantidade com relação aos demais meios. As análises de expressão relativa de genes mostraram indução do gene da b-1,3-glucano sintase e repressão do gene quitina sintase 5 em sacarose e inulina com relação a condição frutose. Estes dados sugerem que a alteração na composição da parede celular do F. solani pode ter relação com a secreção de enzimas nos meios sacarose e inulina. Para N. vasinfecta, quando crescido em sacarose foi observada atividade de transfrutosilação, com a liberação de glucose e síntese de 1-cestose (FOS) no meio. Transfrutosilação também foi observada no meio que teve inulina como fonte de carbono. O micélio deste fungo apresentou alterações visíveis em meio sólido nas condições frutose e inulina, sendo mais hialino do que nas demais condições. A quantidade de quitina na parede celular deste fungo crescido por cinco dias foi maior nas condições frutose e inulina com relação às demais. As análises de expressão relativa de genes mostraram indução dos genes de quitina sintase 4 e 5 nestas duas condições em relação à sacarose. A partir dos resultados, pode-se concluir que as fontes de carbono oferecidas foram utilizadas pelos fungos, que as mesmas afetaram a composição de açúcares da parede celular e a expressão de genes de síntese de componentes da parede e que estes fungos são promissores para a produção de FOS, pois possuem enzimas que hidrolisam a inulina, além de enzimas que sintetizam oligossacarídeos a partir de sacarose por transfrutosilação / Abstract: Fructooligosaccharides (FOS) are low molecular weight fructans produced by microbes and plants. Interest in FOS has been increasing since they are considered as functional food ingredients with benefical effects in human nutrition. With the aim of examining how the production of FOS and the composition of the cell wall of filamentous fungi are affected by the carbon source, Fusarium solani (URM 3338) and Neocosmospora vasinfecta (URM 3329) were cultured in media containing five different carbon sources (sucrose, inulin, glucose, fructose or glucose plus fructose) and samples were taken at 5, 10 and 15 days of growth. From the filtered culture medium, pH, total carbohydrates, reducing sugars and proteins, the presence of FOS and inulinase and invertase activities were analyzed. Mycelium biomass was measured and the cell wall was isolated and its composition in neutral sugars, uronic acids and chitin analyzed. The expression of b-1,3-glucan synthase and chitin synthase genes was also evaluated. Both fungi utilized all the carbon sources for growing. In sucrose- and inulin-containing media, hydrolytic activity was detected in F. solani generating glucose, fructose and FOS as products. When grown on solid culture media, visible changes were observed in mycelium of this fungus only in fructose, but the amount of chitin in the cell wall was higher in the sucrose and inulin-containing media when compared to other carbon sources. The expression b-1,3-glucan synthase gene was induced and chitin synthase 5 gene repressed on sucrose and inulin media. N. vasinfecta showed transfructosilation activity when was grown in sucrose, with release of glucose and synthesis of 1-kestose (FOS) in the culture medium. Transfructosilation was also observed in the inulin-containing medium. The mycelium showed visible changes when the fungus was cultured in solid medium with fructose or inulin as carbon sources. The amount of chitin in the cell wall of this fungus when grown for five days in inulin or fructose was higher in comparison to other carbon sources. The analysis of gene expression showed induction of chitin synthase 4 and 5 genes in these two conditions in relation to sucrose. From the results it can be concluded that the carbon sources affected growth, enzymic activity, composition of the cell wall and gene expression in F. solani and N. vasinfecta, and that these fungi are promising organisms for FOS production since they secrete enzymes that hydrolyze inulin or synthesize oligosaccharides from sucrose by transfructosylation / Doutorado / Biologia Celular / Doutora em Biologia Celular e Estrutural
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Produção de quitina, quitosana e biossurfactante, por Cunninghamella elegans UCP/WFCC 0542 em meio suplemento com residuários agroindustriaisSouza, Daniele Gilvanise de 01 December 2015 (has links)
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Previous issue date: 2015-12-01 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / One of the biggest challenges in biotechnological production is to produce high value-added products at a low cost. In this context, the filamentous fungus Cunninghamella elegans presents in its cell wall large amounts of chitin and chitosan, but is also able to produce
biosurfactants. Chitin and chitosan has a vast field of biotechnological applications, and the bioremediation has been used in the removal and recovery of different waste, pollutant biotransformation and textile effluent discoloration. These biopolymers have linear structures
with monomeric units β-1,4-N-acetyl-D-glucosamine and β-1,4-D-glucosamine, respectively. Furthermore, the surfactants are compounds synthesized by micro-organisms having properties such as reducing surface and interfacial tension, emulsification, solubilization and dispersion phases, being widely applied in the petrochemical industry. Studies with C. elegans UCP/WFCC 0542 were performed in order to evaluate their biotechnological potential for the production of chitin, chitosan and biosurfactant with the use of agroindustrial
residues (corn steep liquor and soybean oil waste), using a central composite design rotational 2². The biopolymers chitin and chitosan were obtained by alkali-acid treatment with 1M sodium hydroxide, and subsequent use of 2% acetic acid. The surface-active properties
of the biosurfactant were evaluated by measuring the surface tension of the metabolic liquid cell-free. Biomass production by C. elegans was 8.12 g/L with yields of 0.095 mg/g chitin and 0.036 mg/g of chitosan with a deacetylation degree of 87.44% in the proposed condition. The
biosurfactant obtained in condition 8 of planning with 2.15% of corn steep liquor and 5.22% soybean oil waste has demonstrated the best surface tension with 28.20 mN/m-1 and showed stability against to different environmental conditions, having anionic character and
its preliminary biochemical composition suggests that the isolated biosurfactant consists of proteins and lipids. Also this proved effective in the removal of petroleum derivatives hydrophobic compounds, removing 55.15% of motor oil, 71.42% of crude petroleum, 77.46%
of kerosene and 96.41% of diesel oil in sand beach. Biosurfactant toxicity tests with Brassica oleracea seeds proved their non-toxic nature. The results show the biotechnological potential of C. elegans from alternative and low cost agroindustrial substrates, allowing its use in bioremediation process in environmental recovery. / Um dos grandes desafios na produção biotecnológica é a produção de insumos de alto valor agregado a um baixo custo. Neste contexto, o fungo filamentoso Cunninghamella elegans apresenta em sua parede celular grandes quantidades de quitina e quitosana, como também
é capaz de produzir biossurfactantes. A quitina e quitosana apresentam um vasto campo de aplicações biotecnológicas, e na biorremediação vem sendo utilizado na remoção e recuperação de diferentes resíduos, biotransformação de poluentes e descoloração de
efluente têxtil. Estes biopolímeros possuem estruturas lineares, com unidades monoméricas β-1,4-N-acetil-D-glicosamina e β-1,4-D-glicosamina, respectivamente. Por outro lado, os biossurfactantes são compostos sintetizados por micro-organismos, apresentando
propriedades como a redução da tensão superficial e interfacial, emulsificação, solubilização e dispersão de fases, sendo muito aplicado na indústria petroquímica. Estudos com Cunninghamella elegans UCP/WFCC 0542 foram realizados com objetivo de avaliar o seu potencial biotecnológico para a produção de quitina, quitosana e biossurfactante com a utilização de resíduos agroindustriais (milhocina e óleo de soja pós-fritura), através de um delineamento central composto rotacional de 2². Os biopolímeros quitina e quitosana foram
obtidos através de tratamento álcali-ácido, com hidróxido de sódio 1M, e posterior emprego de ácido acético a 2%. As propriedades tensoativas do biossurfactante foram avaliadas pela determinação da tensão superficial do líquido metabólico livre de células. A produção de
biomassa por C. elegans foi de 8,12 g/L de com rendimentos de 0,095 mg/g de quitina e 0,036 mg/g de quitosana, com um grau de desacetilação de 87,44%, na condição proposta. O biossurfactante obtido na condição 8 do planejamento com 2,15% de milhocina e 5,22% de óleo de soja pós-fritura demonstrou a melhor tensão superficial com 28,20 mN/m-1 e apresentou estabilidade frente a diferentes condições ambientais, possuindo caráter aniônico e sua composição bioquímica preliminar sugere que o biossurfactante isolado seja constituído por proteínas e lipídeos. Também este se mostrou eficiente na remoção de compostos hidrofóbicos derivados do petróleo, com remoção de 55,15% de óleo de motor, 71,42% de petróleo bruto, 77,46% de querosene e 96,41% de óleo diesel em areia de praia.
Testes de toxicidade do biossurfactante com sementes de Brassica oleracea provaram seu caráter atóxico. Os resultados obtidos demonstram o potencial biotecnológico de C. elegans a partir substratos agroindustriais alternativos e de baixo custo, possibilitando o seu emprego em processo de biorremediação na recuperação ambiental.
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Bioprospecção de fungos filamentosos (Ascomycetes) isolados de sedimento de mangue para produção do complexo enzimático celulolítico utilizando resíduos agroindustriais com substratos.Mororó, Maria Cleudenôra Cássia 30 August 2017 (has links)
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Previous issue date: 2017-08-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES# / #2075167498588264571# / #600 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq# / #-2555911436985713659# / #600 / Cellulases (E.C. 3.2.1.4) are enzymes responsible for the degradation of cellulose, are molecules capable of accelerating chemical reactions and breaking the chemical bonds between glucose units. Cellulases correspond to the complex consisting of three enzymes endoglucanases, exoglucanases and beta-glucosidases, with diverse applications, being the microbial biotechnological processes responsible for a great part of the world economy, yet the costs of production are still very high. In this context, 25 strains of filamentous fungi (Ascomycetes) isolated from mangrove sediments of Rio Formoso, PE, Brazil, were investigated to investigate the production potential of the enzymes of the cellulolytic complex. The initial studies were carried out by selecting the fungi with the highest enzymatic activity, through the detection of cellulolytic activity in solid synthetic medium, with carboxymethylcellulose (CMC) as the substrate. The results indicated the presence of the cellulase enzyme through the formation of halo in 3 strains of the genus Trichoderma, 3 strains of the genus Aspergillus and 1 strain of the genus Penicillium. The most representative enzymatic indices were those of Penicillium sp. UCP 0279 with Index of 2,2, followed by Aspergillus flavus UCP 1413 with enzymatic index of 1,7. Submerged fermentations were carried out to evaluate the endoglucanase activity, exoglucanase and β-glycosidase, using agroindustrial residues, tangerine peel, pineapple peel, pineapple crown, wheat bran and corn bran as substrate. The results indicated a CMCase activity of 20.2 IU / mL for Penicillium sp. UCP 0279, with wheat bran as substrate in 72 h of fermentation and an activity of 18.3 IU / mL in 24 h with the pineapple crown. For the Aspergillus flavus UCP 1413, the yield was 14.9 IU / mL and 14.5 IU / mL with the residues of corn bran and pineapple peel respectively, and both results were obtained with 24 h of fermentation. The FPase activity for Penicillium sp. UCP 0279, using pineapple peel as substrate had 45.5 IU / mL and the tangerine peel 42.8 IU / mL, both in fermentation at 48 h. For A. flavus UCP 1413 the pineapple crown presented 25.0 IU / mL enzymatic activity in 24 h and the pineapple peel 14.4 U / mL at the same time. In the activity of the enzyme β-glycosidase, Penicillium sp. UCP 0279 showed a production of 18.2 IU / mL in 24 h, with the pineapple crown residue and the pineapple peel had 9.1 IU / mL in 48 h. The A. flavus UCP 1413 presented with 96 h of fermentation an activity of 16.9 U / mL and 14.5 U / mL, with wheat bran and corn bran, respectively. / As celulases (E.C. 3.2.1.4) são enzimas responsáveis pela degradação da celulose, são moléculas capazes de acelerar reações químicas e realizar a quebra das ligações químicas existentes entre as unidades de glicose. As celulases correspondem ao complexo constituído por três enzimas endoglucanases, exoglucanases e beta-glicosidases, com diversas aplicações, sendo os processos biotecnológicos microbianos responsáveis por uma grande parcela da economia mundial, contudo os custos de produção ainda são muito elevados. Neste contexto, foi realizada a bioprospecção de 25 linhagens de fungos filamentosos (Ascomycetes) isolados de sedimentos de mangue do município Rio Formoso, PE, Brasil, investigando o potencial de produção das enzimas do complexo celulolítico. Os estudos iniciais foram realizados selecionando os fungos com maior atividade enzimática, através da detecção da atividade celulolítica em meio sintético sólido, tendo como substrato a carboximetilcelulose (CMC). Os resultados indicaram a presença da enzima celulase através da formação do halo em 3 linhagens do gênero Trichoderma, 3 linhagens do gênero Aspergillus e 1 linhagem do gênero Penicillium. Os índices enzimáticos mais representativos foram os de Penicillium sp. UCP 0279 com Índice de 2,2, seguido de Aspergillus flavus UCP 1413 com índice enzimático de 1,7. Em seguida, foram realizadas fermentações submersas para avaliação da atividade endoglucanase, exoglucanase e β-glicosidase, utilizando resíduos agroindustriais, casca de tangerina, casca de abacaxi, coroa de abacaxi, farelo de trigo e farelo de milho como substrato. Os resultados indicaram uma atividade para CMCase de 20,2 UI/mL para Penicillium sp. UCP 0279, com farelo de trigo como substrato em 72 h de fermentação e com a coroa de abacaxi observou-se uma atividade de 18,3 UI/mL em 24 h. Para o Aspergillus flavus UCP 1413, a produção foi de 14,9 UI/mL e 14,5 UI/mL com os resíduos de farelo de milho e de casca de abacaxi respectivamente, e ambos os resultados foram obtidos com 24 h de fermentação. A atividade FPase para Penicillium sp. UCP 0279, usando casca de abacaxi como substrato apresentou 45,5 UI/mL e a casca de tangerina 42,8 UI/mL, ambos em fermentação a 48 h. Para A. flavus UCP 1413 a coroa de abacaxi apresentou 25,0 UI/mL de atividade enzimática em 24 h e a casca de abacaxi 14,4 U/mL no mesmo tempo. Na atividade da enzima β-glicosidase o Penicillium sp. UCP 0279 apresentou uma produção de 18,2 UI/mL em 24 h, com o resíduo da coroa de abacaxi e com a casca de abacaxi apresentou 9,1 UI/mL em 48 h. O A. flavus UCP 1413 apresentou com 96 h de fermentação uma atividade de 16,9 U/mL e 14,5 U/mL, com farelo de trigo e farelo de milho respectivamente.
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