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1

Hurmann, Eliéte Moura de Souza. "Atividade antimicrobiana de Trichoderma viride e Trichoderma stromaticum." Universidade Estadual do Oeste do Parana, 2016. http://tede.unioeste.br:8080/tede/handle/tede/1823.

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Fundação Araucária
Trichoderma spp. is a promising antagonist, the development and use of products based on this organism gives us the opportunity not only to reduce health risks, but also costs and environmental damage. This work aimed to analyze the efficiency of Trichoderma viride extracts and Trichoderma stromaticum against some microorganisms of interest in clinical medicine, agriculture and fish farming. Among them Colletotrichum musae, banana anthracnose causes, Saprolegnia, which affects fish eggs and some bacteria that cause harm to human health. The dichlorometane extracts were tested at various concentrations, and as positive control a commercial antimicrobial. Inhibition of the pathogen was verified directly by paired cultivation technique. The antimicrobial activity of the extracts was evaluated by disk diffusion and the determination of minimum inhibitory concentration (MIC) by microdilution test broth. In situ tests were done in the fruit inoculating the pathogenic fungus and treated with the extracts and the sensory analysis where it was determined the acceptance of the product. In cultivation paired the Trichoderma spp. inhibited the growth of pathogens being 0.05% significance level. In the disk diffusion test results were positive, and for E. coli and Aeromonas hydrophila gave the best results. MIC against microorganisms of the extracts ranged from 50% to 3,125%. Given the results presented, it is concluded that the extracts were effective in in vitro inhibition of the microorganisms as well as their application in the fruits did not alter the organoleptic characteristics.
O Trichoderma spp. é um antagonista promissor, o desenvolvimento e uso de produtos à base deste microrganismo nos oferece a oportunidade, não apenas de reduzir os riscos da saúde, mas também custos e danos ambientais. Assim, este trabalho teve por objetivo analisar a eficiência dos extratos de Trichoderma viride e Trichoderma stromaticum contra alguns microrganismos de interesse na clínica médica, agricultura e piscicultura. Dentre eles o Colletotrichum musae, causador da antracnose da banana, Saprolegnia, que acomete ovas de peixes e algumas bactérias que causam danos à saúde humana. Os extratos diclorometânicos foram testados em várias concentrações, tendo como controle positivo um antimicrobiano comercial. A inibição do patógeno foi verificada, de forma direta pela técnica de cultivo pareado. A atividade antimicrobiana dos extratos foi avaliada por disco-difusão e pela determinação da concentração inibitória mínima (MIC) por teste de microdiluição em caldo. Foram feitos testes in situ no fruto inoculando o fungo patogênico e tratados com os extratos e a análise sensorial onde foi determinada a aceitação do produto. No cultivo pareado os Trichoderma spp. inibiram o crescimento dos patógenos sendo 0,05% de significância. No teste de disco-difusão os resultados foram positivos, sendo que para Aeromonas hydrophila e E. coli obteve-se os melhores resultados. O MIC (concentração inibitória mínima)dos extratos contra os microrganismos variou de 50% a 3,125 %. Diante dos resultados apresentados, evidenciou-se que, os extratos foram eficientes na inibição in vitrodos microrganismos testados, bem como sua aplicação nos frutos não alterou as características organolépticas dos mesmos.
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2

Parzianello, Francini Requia. "USO DE POLÍMEROS EM FORMULAÇÕES PARA ARMAZENAMENTO DE Trichoderma harzianum E Trichoderma viride." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/4851.

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Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul
Trichoderma spp. is one of the most studied funguses as a biocontrol agent, being antagonistic to various plant pathogens in different cultures. This work aimed the production of liquid bio formulate of Trichoderma harzianum and Trichoderma viride based on biopolymer Xanthan Gum (GX) and carboxymethylcellulose (CMC) and the polymer polyvinylpyrrolidone (PVP).The bio formulates were composed of glycerol 10.0 gL -1, yeast extract 0.5 gL -1, MgSO 4 .7 H 2 0 0.2 gL -1, K 2 HPO 4 0.5 gL -1 and NaCl 0.1 gL -1. These amounts were determined by assessing the shortest period of time between the inoculation and sporulation of the fungus in Petri dishes containing PDA culture medium (potato dextrose agar) and bio formulates. The purpose of the use of these products were to make available a formulation that presents 180 days of shelf validity, as regarding the survival parameters (number of spores), evaluated using a Neubauer chamber and infectivity in vitro evaluated by testing direct confrontation with Fusarium oxysporum Schlecht . The evaluations were performed at intervals of 30, 60, 90, 120 and 180 days. The treatments used were G 1 P 1 C 2 (GX, 1.0 gL -1; PVP, 1.0 gL -1; CMC, 2.0 g L -1), G 0.5 P0.5 C1 (GX, 0.5 gL -1; PVP, 0.5 gL -1; CMC, 1.0 g L -1), G 2P 2C (GX, 2.0 gL -1; PVP, 2.0 gL-1) and GPC1 (CMC, 1.0 gL-1), stored in sterile plastic container at room temperature. T. harzianum showed the best result with G 0.5 P0.5C 1 in all periods of assessment. For T. viride none of the treatments was better than the control in the assessed periods. Polymers make possible to develop effective means of storage, extending the life of bio formulates.
Trichoderma spp. é um dos fungos mais pesquisados como agente de biocontrole, sendo antagonista a vários fitopatógenos em diferentes culturas. Este trabalho teve como objetivo a produção de bioformulado líquido de Trichoderma harzianum e Trichoderma viride a base de biopolímeros Goma Xantana (GX) e Carboximetilcelulose (CMC) e o polímero Polivinilpirrolidona (PVP). Os bioformulados foram compostos por glicerol 10,0 gL-1, extrato de levedura 0,5 gL-1, MgSO4.7H20 0,2 gL-1, K2HPO4 0,5 gL-1 e NaCl 0,1 gL-1. As quantidades foram determinadas através da avaliação do menor período de tempo entre a repicagem e a esporulação do fungo em placas de Petri, contendo meio de cultura BDA (batata dextrose ágar) e os bioformulados. A finalidade do uso destes produtos foi disponibilizar uma formulação que apresente 180 dias de validade em prateleira, quanto aos parâmetros sobrevivência (número de esporos), avaliado através de Câmara de Neubauer e infectividade in vitro avaliado através de teste de confrontação direta com Fusarium oxysporum Schlecht. Os intervalos de avaliações ocorreram aos 30, 60, 90, 120 e 180 dias. Os tratamentos utilizados foram G1P1C2 (1,0gL-1 GX, 1,0 gL-1 PVP, 2,0 gL-1 CMC), G0,5P0,5C1 (0,5 gL-1 GX, 0,5 gL-1 PVP, 1,0 gL-1 CMC), G2P2C (2,0 gL-1 GX, 2,0 gL-1 PVP) e GPC1 (1,0 gL-1 CMC), armazenados em embalagens plásticas e estéreis, em temperatura ambiente. T. harzianum apresentou melhor resultado com G0,5P0,5C1 em todos períodos de avaliação. Para T. viride nenhum dos tratamentos foi melhor do que o controle nos períodos avaliados. Os polímeros permitem desenvolver meios eficazes de armazenamento, prolongando a vida útil de bioformulados.
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3

Ulhoa, Cirano Jose. "Chitinolytic system in Trichoderma harzianum." Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335203.

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4

Chondrogianni, J. "Biosynthesis and synthesis of Trichoderma isonitriles." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371517.

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5

Muthumeenakshi, Sreenivasaprasad. "Molecular taxonomy of the genus Trichoderma." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264087.

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6

Voltatodio, Maria Luiza. "Caracterização bioquímica e biofísica da Celobiohidrolase II do fungo Trichoderma harzianum IOC3844 produzida por expressão homóloga." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-19102012-090550/.

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O esgotamento das reservas, especialmente do petróleo mais fino, aliado à crescente demanda energética e à necessidade inadiável de reduzir as emissões de carbono para a atmosfera, sinalizam para a necessidade da busca de novas fontes de energia renováveis e limpas. As preocupações com o aquecimento global têm feito crescer o interesse mundial pelos biocombustíveis. O novo conceito de biocombustíveis de segunda geração corresponde à produção de etanol combustível a partir de biomassa lignocelulósica como matéria-prima. No entanto, para tornar possível a utilização da biomassa é necessária a conversão das moléculas constituintes da parede celular em açúcares fermentáveis. A tecnologia mais promissora para a conversão dessa biomassa lignocelulósica à etanol combustível é com base na hidrólise enzimática da celulose usando celulases. Alguns microrganismos como o fungo Trichoderma SSP. secretam um eficiente complexo enzimático de celulases. Tendo as celobiohidrolases, elevada importância na hidrólise primária da celulose, o objetivo desse trabalho foi realizar a caracterização bioquímica e biofísica a celobiohidrolase II (CBHII) do complexo de celulases do fungo filamentoso Trichoderma harzianum IOC 3844. A enzima depois de purificada mostrou uma melhor atividade contra o substrato pNPC a 60°C em pH 4,8. Estudos de eletroforese capilar mostraram apenas moléculas com uma unidade de glicose para um substrato simples inicial contendo 5 glicoses. Análises de dicroísmo circular mostraram um padrão de estrutura secundária predominante em alfa hélice, e na análise da estrutura terciária, o espectro de emissão da CBHII mostrou um comprimento de onda de fluorescência máxima a 333nm em pH5,0, indicando que os triptofanos estão parcialmente expostos ao solvente. Ensaios utilizando a técnica de espalhamento de luz a baixo ângulo, permitiram a geração de um modelo tridimensional o qual mostrou-se domínios globulares unidos por um linker, e as posições relativas entre eles, demonstrando grande similaridade com enzimas CBHII já descritas na literatura, e sendo assim, de grande interesse biotecnológico para hidrólises de biomassas.
The depletion of reserves, especially of refined oil , with increased energy demands and the urgent need to reduce the carbon emissions on the atmosphere, signals the necessity to search for new sources of energy renewable and clean. Concerns about global warming have led to an increased world interest in biofuels. The new concept of second generation biofuels corresponds to fuel ethanol production from biomass lignocellulosic feedstock. However, to make possible the use of biomass is necessary the conversion of cell-wall molecules into fermentable sugars. The most promising technology for the conversion of lignocellulosic biomass to ethanol fuel is based on the enzymatic degradation of cellulose using cellulase. Some microorganisms such Trichoderma ssp. secretes an efficient enzymatic complex of cellulase. Since the cellobiohydrolases are highly importance in the primary hydrolysis of cellulose, the objective of this study was to perform the biochemical and biophysical characterization of cellobiohydrolase II (CBHII) present into the cellulase complex from the Trichoderma harzianum IOC 3844. The enzyme showed its better activity against pNPC at 60°C and pH 4,8. Capillary electrophoresis showed only glucose molecules as the final product of C5 oligosaccharide hydrolysis. Circular dichroism analysis showed a pattern of secondary structure mainly composed of alpha helix, and the tertiary structure analysis by the emission spectrum of the CBHII showed a wavelength of maximum fluorescence at 33nm at pH 5, indicating that the tryptophans are exposed to solvent. The three dimensional model generated by SAXS showed a structure with two globular domains joined by a linker, and the relative positions among them exhibited great similarity with CBHII described on the literature, and thus, presenting a great biotechnological interest for hydrolysis of biomass.
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7

Carneiro, Andréia Aparecida Jacomassi [UNESP]. "Produção de β-glucanases por Trichoderma reesei e Trichoderma harzianum e aplicação na hidrólise de β-glucanas." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/103972.

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As glucanas fúngicas têm sido muito estudadas por apresentarem respostas biológicas benéficas à saúde. O Agaricus blazei, conhecido popularmente como cogumelo do sol, é um basidiomiceto que apresenta propriedades funcionais devido às β-glucanas. Os fungos Trichoderma harzinaum e Trichoderma reesei foram capazes de se desenvolverem em Agaricus blazei em pó como única fonte de carbono produzindo β-1,3-glucanases, analisadas por superfície de resposta. As enzimas hidrolisaram β-glucanas de A. blazei e produziu glucose e diferentes glucooligossacarídeos. As enzimas brutas do T. harzianum e T. reesei hidrolisaram menos de 15 % de glucana e em torno de 40 % de laminarina (β-1,3 glucana comercial), após 60 minutos, respectivamente. Utilizando a β-1,3-glucanase bruta de T. harzianum foram detectados gentiobiose e laminaritriose nos hidrolisados enzimáticos de β- glucana e laminarina, enquanto a laminaritetraose, celotetraose e celotriose foram identifificados e quantificados apenas nos hidrolisados de β-glucana de A. blazei. A ação da β- 1,3-glucanase bruta de T. reesei sobre a laminarina e glucana de A. blazei resultou em glicose e gentiobiose. O que sugere uma possível diferença na ação catalítica das duas enzimas. As enzimas parcialmente purificadas do T. harzianum e T. reesei hidrolisaram 47 e 85 % de laminarina, respectivamente. A β-1,3-glucanase purificada de T. harzianum não degradou a glucana de A. blazei, e a enzima purificada de T. reesei degradou 2,6 % de glucana, após 60 minutos, no entanto, gentiobiose e laminaritriose foram detectados no hidrolisado de laminarina. Utilizando a enzima parcialmente purificada de T. reesei gentiobiose foi detectado no hidrolisado de glucana e de laminarina, e celotriose e laminaritriose foram detectados apenas no hidrolisado de laminarina. A fim de conhecer melhor...
Fungal glucans have been studied extensively because of their biological responses, which have been shown to possess health benefits. Agaricus blazei, commonly known as mushroom of the sun, is a basidiomycete that has functional properties because of its β-glucans. The fungi Trichoderma harzinaum and Trichoderma reesei were able to develop in a powdered form of A. blazei, which served as the only carbon source. The result was the production of β- 1,3-glucanases, which were analyzed using response surface methodology. The enzymes hydrolyzed the β-glucans of A. blazei, and produced glucose and different glucooligosaccharides. The crude enzymes of T. harzianum and T. reesei hydrolyzed less than 15% of glucan and approximately 40% of laminarin after 60 minutes, respectively. Using crude β-1,3-glucanase from T. harzianum, gentiobiose and laminaritriose were detected in enzymatic hydrolysates of β-glucan and laminarin, while laminaritetraose, cellotriose and celotetraose were identified and quantified only in the hydrolysates of the β-glucan of A. blazei. The action of the crude β-1,3-glucanase of T. reesei on the laminarin and glucan of A. blazei resulted in glucose and gentiobiose. These results suggest a possible difference in the catalytic action of the two enzymes. The partially purified enzymes of T. harzianum and T. reesei hydrolyzed 47% and 85% of laminarin, respectively. The purified β-1,3-glucanase from T. harzianum did not degrade the glucan of A. blazei, and the purified enzyme from T. reesei degraded 2.6% of the glucan after 60 minutes; however, gentiobiose and laminaritriose were detected in the hydrolyzates of laminarin. Using partially purified enzymes from T. reesei, gentiobiose was detected in the hydrolyzates of both glucan and laminarin, and laminaritriose and cellotriose and were detected... (Complete abstract click electronic access below)
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8

Carneiro, Andréia Aparecida Jacomassi. "Produção de β-glucanases por Trichoderma reesei e Trichoderma harzianum e aplicação na hidrólise de β-glucanas /." Rio Claro : [s.n.], 2012. http://hdl.handle.net/11449/103972.

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Orientador: Roberto da Silva
Banca: Adalberto Pessoa Junior
Banca: Inês Conceição Roberto
Banca: Eleonora Cano Carmona
Banca: Eleni Gomes
Resumo: As glucanas fúngicas têm sido muito estudadas por apresentarem respostas biológicas benéficas à saúde. O Agaricus blazei, conhecido popularmente como cogumelo do sol, é um basidiomiceto que apresenta propriedades funcionais devido às β-glucanas. Os fungos Trichoderma harzinaum e Trichoderma reesei foram capazes de se desenvolverem em Agaricus blazei em pó como única fonte de carbono produzindo β-1,3-glucanases, analisadas por superfície de resposta. As enzimas hidrolisaram β-glucanas de A. blazei e produziu glucose e diferentes glucooligossacarídeos. As enzimas brutas do T. harzianum e T. reesei hidrolisaram menos de 15 % de glucana e em torno de 40 % de laminarina (β-1,3 glucana comercial), após 60 minutos, respectivamente. Utilizando a β-1,3-glucanase bruta de T. harzianum foram detectados gentiobiose e laminaritriose nos hidrolisados enzimáticos de β- glucana e laminarina, enquanto a laminaritetraose, celotetraose e celotriose foram identifificados e quantificados apenas nos hidrolisados de β-glucana de A. blazei. A ação da β- 1,3-glucanase bruta de T. reesei sobre a laminarina e glucana de A. blazei resultou em glicose e gentiobiose. O que sugere uma possível diferença na ação catalítica das duas enzimas. As enzimas parcialmente purificadas do T. harzianum e T. reesei hidrolisaram 47 e 85 % de laminarina, respectivamente. A β-1,3-glucanase purificada de T. harzianum não degradou a glucana de A. blazei, e a enzima purificada de T. reesei degradou 2,6 % de glucana, após 60 minutos, no entanto, gentiobiose e laminaritriose foram detectados no hidrolisado de laminarina. Utilizando a enzima parcialmente purificada de T. reesei gentiobiose foi detectado no hidrolisado de glucana e de laminarina, e celotriose e laminaritriose foram detectados apenas no hidrolisado de laminarina. A fim de conhecer melhor... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Fungal glucans have been studied extensively because of their biological responses, which have been shown to possess health benefits. Agaricus blazei, commonly known as "mushroom of the sun," is a basidiomycete that has functional properties because of its β-glucans. The fungi Trichoderma harzinaum and Trichoderma reesei were able to develop in a powdered form of A. blazei, which served as the only carbon source. The result was the production of β- 1,3-glucanases, which were analyzed using response surface methodology. The enzymes hydrolyzed the β-glucans of A. blazei, and produced glucose and different glucooligosaccharides. The crude enzymes of T. harzianum and T. reesei hydrolyzed less than 15% of glucan and approximately 40% of laminarin after 60 minutes, respectively. Using crude β-1,3-glucanase from T. harzianum, gentiobiose and laminaritriose were detected in enzymatic hydrolysates of β-glucan and laminarin, while laminaritetraose, cellotriose and celotetraose were identified and quantified only in the hydrolysates of the β-glucan of A. blazei. The action of the crude β-1,3-glucanase of T. reesei on the laminarin and glucan of A. blazei resulted in glucose and gentiobiose. These results suggest a possible difference in the catalytic action of the two enzymes. The partially purified enzymes of T. harzianum and T. reesei hydrolyzed 47% and 85% of laminarin, respectively. The purified β-1,3-glucanase from T. harzianum did not degrade the glucan of A. blazei, and the purified enzyme from T. reesei degraded 2.6% of the glucan after 60 minutes; however, gentiobiose and laminaritriose were detected in the hydrolyzates of laminarin. Using partially purified enzymes from T. reesei, gentiobiose was detected in the hydrolyzates of both glucan and laminarin, and laminaritriose and cellotriose and were detected... (Complete abstract click electronic access below)
Doutor
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9

Grinyer, Jasmine. "Proteomic analysis of the biological control fungus Trichoderma." Doctoral thesis, Australia : Macquarie University, 2007. http://hdl.handle.net/1959.14/12407.

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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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10

Dodd-Wilson, Sarah Louise. "Biochemical and Molecular characterisation of Trichoderma species." Thesis, University of Auckland, 1996. http://hdl.handle.net/2292/1916.

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The growing importance of many Trichoderma strains as biological control agents and producers of valuable metabolites and enzymes has made their distinction from other Trichoderma isolates essential. However, the use of morphological and cultural characters alone to differentiate individuals within the genus Trichoderma to a level that is most informative has proved difficult due to a lack of reliable characters. In this study, alternative biochemical and molecular techniques were assessed for their ability to differentiate between isolates of the genus Trichoderma. Fifty isolates representing the Trichoderma species T. atroviride, T. hamatum, T. inhamatum, T. koningii, T. virens, T. viride and five morphological sub-groupings of the T. harzianum species were examined. ITS sequence data, RAPD PCR and the ability of an isolate to produce the metabolite 6-pentyl-α-pyrone (PAP) were all used to differentiate between morphologically indistinguishable isolates. Altogether four levels of variation were recognised. The greatest level of resolution was achieved with the RAPD PCR technique, followed by both morphological characters and sequence data from the ITSI region of the ribosomal gene complex. Sequence data from the ITS2 region provided the third level of resolution. The fourth level of resolution was achieved with both sequence data from the second variable region (D2) of the 28S-like ribosomal gene and determination of an isolate's ability to produce the metabolite PAP. Based on these results, it was proposed that a new taxonomic system be established in which individuals of the genus Trichoderma are distinguished by a combination of morphological, cultural. biochemical and molecular characters. Sequence data and RAPD PCR data were also tested for their reliability in estimating the phylogeny of Trichoderma. Sequence data from the ITSI region proved to be the most reliable for predicting the phylogeny of morphologically defined species, whereas RAPD data was most useful for predicting the unrooted phylogeny of strains of morphologically identical isolates (i.e. isolates with less than 10% nucleotide divergence). None of the data employed in the present study were able to resolve all the species tested. It was concluded that additional sequence from a more variable region would be required to achieve this. In addition to the characterisation and phylogenetic studies, two approaches were undertaken in an attempt to isolate a gene(s) vital to the production of the antifungal metabolite PAP, a metabolite believed to be important in the biological control activity of a number of the isolates under investigation. Both attempts were unsuccessful and additional studies undertaken to determine how important PAP is in the biological control activity of Trichoderma isolates were inconclusive. Nevertheless, a natural PAP deficient mutant was identified among the 50 isolates under investigation. Furthermore, synthetic PAP was found to inhibit the infection of lentil seedlings by Sclerotium rolfsii when 10 mg was added to a pot containing six seedlings and three viable sclerotia of the pathogen. The metabolite did not appear to have any detrimental effects on the growth and development of the seedlings.
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11

Lajoie, Denis. "Lactose hydrolases de Trichoderma reesei MCG-80." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq26227.pdf.

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12

Saraiva, NatÃlia Nogueira. "Estudo QuÃmico do Fungo Antagonista Trichoderma harzianum." Universidade Federal do CearÃ, 2009. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=4663.

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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
A investigaÃÃo do potencial quÃmico de Trichoderma harzianum, um fungo antagonista, foi realizada. A composiÃÃo de Ãcidos graxos produzidos pelo fungo cultivado em Czapeck, peptona e caldo de batata, variando a fonte de carbono (glicose e manitol), nesse Ãltimo meio, foi determinada por CG/EM. Foram identificados os seguintes Ãcidos graxos na forma dos seus Ãsters metÃlicos: hexadecanÃico (C16:0), octadecanÃico (C18:0), 9-octadecenÃico (C18:1) e 9,12-octadienÃico (C18:2). Dos extratos orgÃnicos do fungo cultivado em peptona por 16 dias e BD (Batata-dextrose) por 24 dias foi possÃvel isolar o manitol e o composto antimicrobiano viridiofungina A, respectivamente. Extratos e fraÃÃes foram submetidos a testes antitumorais frente Ãs linhagens tumorais humanas MDA-MB435 (mama), HCT-8 (cÃlon) e SF-295 (glioblastoma) e cinco das fraÃÃes testadas apresentaram CI50 75% em pelo menos duas linhagens tumorais. A atividade alcooldesidrogenases (ADHs) de T. harzianum foi identificada e o microrganismo foi empregado como biocatalisador na reduÃÃo da (R)- carvona, acetofenona e seis alquilfenonas. Na maioria dos casos, os produtos de biorreduÃÃo foram obtidos.
The chemical potential of Trichoderma harzianum, an antagonist fungus, was investigated. The fatty acid composition of this fungus grown in Czapeck, peptone and potato, with different carbon source (glycose and manitol) in the later medium, was determined after GC/MS analysis. The following fatty acids, as their methyl esters, were identified: hexadecanoic (C16:0), octadecanoic (C18:0), 9-octadecenoic (C18:1) and 9,12-octadienoic (C18:2). From the organic extracts of the microorganism cultivated in peptone (16 days) and potatodextrose (21 days) broths, manitol and the antimicrobial viridiofungin A were isolated, respectively. Extracts and fractions were submitted to antitumor assays against the human cell tumor lines MDA-MB435 (mama), HCT-8 (colon) e SF-295 (glioblastoma) and five of them showed IC50 75 % in two or three cell lines. Alcohol dehydrogenases (ADHs) activity of T. harzianum was identified and this microorganism was used as biocatalyst in the reduction of (R)-carvone, acetophenone and six akylphenones. In most cases, the products of the bioreductions were obtained.
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13

Vaz, Madalena. "Caracterização do gene LIP2 de Trichoderma harzianum." Master's thesis, Instituto Politécnico de Bragança, Escola Superior Agrária, 2010. http://hdl.handle.net/10198/5816.

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Os fungos do género Trichoderma abrangem um grupo de fungos extremamente comuns em solos de todas as zonas climáticas. São eficientes produtores de enzimas com aplicações industriais, ou na natureza, estando envolvidos na degradação da parede celular dos fitopatogénios bem como na degradação de outros fungos, matéria orgânica e nutrientes secretados pelas raízes. As estirpes de Trichoderma produzem enzimas extracelulares e antibióticos com efeitos antifúngicos, sobretudo T. harzianum, T. virens e T. viride, sendo por isso usados como agentes de biocontrolo. De entre as enzimas de degradação das paredes celulares produzidas, encontram-se β-1,3 e β-1,6 glucanases, quitinases e proteases. Pensa-se que também as lipases poderão estar envolvidas na actividade enzimática de biocontrolo. Este trabalho teve como objectivo a caracterização do gene lip2 de Trichoderma harzianum, para isso recorreu-se a um conjunto de ferramentas de biologia molecular, bem como o recurso a programas bioinformáticos, de forma a efectuar a caracterização do gene, contribuindo assim para um melhor conhecimento deste. Procedeu-se à clonagem do gene lip2 num sistema de expressão, usando o vector pET-28a(+), e à avaliação da expressão da proteína lip2 por gel de SDS-PAGE em diferentes tempos de indução. Os resultados obtidos na clonagem indicaram uma banda total de 6584pb o que comprovou o sucesso da clonagem. A expressão da proteína após 8 horas de indução manifestou-se pela presença de uma banda de peso molecular estimado de 44kDa, observada por gel SDS-PAGE.T
richoderma spp. covers a group of fungi extremely common in soils of all climatic areas. These fungi are efficient enzyme producers, with indústrial applications, or in nature, involved in the degradation of the cell wall of the phytopathogens as well as in the degradation of other fungi, organic matter and nutrients secreted by roots. Trichoderma strains produce extracellular enzymes and antibiotics with antifungal effects, mainly T. harzianum, T. virens and T. viride, being by this way used as biocontrol agents. Among the degradation enzymes of the cells walls produced, are β-1,3 and β-1,6 glucanases, chitinases and proteases. Lipases could also be involved in enzymatic activity related with biocontrol. This work intention was the characterization of the lip2 gene of the T. harzianum, thus were used a set of tools from molecular biology and bioinformatics tools in order to perform the study, contributing for a better knowledge of the gene. Lip2 gene was cloned in an expression system, using the pET-28a(+) vector, and the expression evaluation of the lip2 protein was made in a SDS-PAGE gel at different induction times. The obtained results in the cloning showed a 6584bp band indicating that the cloning was well succeeded. The protein expression was verified at 8 hours of induction by the presence of a band with an estimated molecular weight of 44kDa, in a SDS-PAGE gel.
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Zhang, Qin. "COLLECTION OF TRICHODERMA REESEI CELLULASE BY FOAMING." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1195069754.

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15

Heikinheimo, Lea. "Trichoderma reesei cellulases in processing of cotton /." Espoo : Technical Research Centre of Finland, 2002. http://www.vtt.fi/inf/pdf/publications/2002/P483.pdf.

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16

Saraiva, Natália Nogueira. "Estudo Químico do Fungo Antagonista Trichoderma harzianum." reponame:Repositório Institucional da UFC, 2009. http://www.repositorio.ufc.br/handle/riufc/10370.

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SARAIVA, N. N. Estudo Químico do Fungo Antagonista Trichoderma harzianum. 2009. 126 f. Dissertação (Mestrado em Química) - Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2009.
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The chemical potential of Trichoderma harzianum, an antagonist fungus, was investigated. The fatty acid composition of this fungus grown in Czapeck, peptone and potato, with different carbon source (glycose and manitol) in the later medium, was determined after GC/MS analysis. The following fatty acids, as their methyl esters, were identified: hexadecanoic (C16:0), octadecanoic (C18:0), 9-octadecenoic (C18:1) and 9,12-octadienoic (C18:2). From the organic extracts of the microorganism cultivated in peptone (16 days) and potatodextrose (21 days) broths, manitol and the antimicrobial viridiofungin A were isolated, respectively. Extracts and fractions were submitted to antitumor assays against the human cell tumor lines MDA-MB435 (mama), HCT-8 (colon) e SF-295 (glioblastoma) and five of them showed IC50 75 % in two or three cell lines. Alcohol dehydrogenases (ADHs) activity of T. harzianum was identified and this microorganism was used as biocatalyst in the reduction of (R)-carvone, acetophenone and six akylphenones. In most cases, the products of the bioreductions were obtained.
A investigação do potencial químico de Trichoderma harzianum, um fungo antagonista, foi realizada. A composição de ácidos graxos produzidos pelo fungo cultivado em Czapeck, peptona e caldo de batata, variando a fonte de carbono (glicose e manitol), nesse último meio, foi determinada por CG/EM. Foram identificados os seguintes ácidos graxos na forma dos seus ésters metílicos: hexadecanóico (C16:0), octadecanóico (C18:0), 9-octadecenóico (C18:1) e 9,12-octadienóico (C18:2). Dos extratos orgânicos do fungo cultivado em peptona por 16 dias e BD (Batata-dextrose) por 24 dias foi possível isolar o manitol e o composto antimicrobiano viridiofungina A, respectivamente. Extratos e frações foram submetidos a testes antitumorais frente às linhagens tumorais humanas MDA-MB435 (mama), HCT-8 (cólon) e SF-295 (glioblastoma) e cinco das frações testadas apresentaram CI50 75% em pelo menos duas linhagens tumorais. A atividade alcooldesidrogenases (ADHs) de T. harzianum foi identificada e o microrganismo foi empregado como biocatalisador na redução da (R)- carvona, acetofenona e seis alquilfenonas. Na maioria dos casos, os produtos de biorredução foram obtidos.
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17

Lima, Fernanda Blauth de. "Secretômica de Trichoderma atroviride e Trichoderma harzianum frente a Guignardia e citricarpa, agente etiológico da Pinta Preta dos Citros." reponame:Repositório Institucional da UCS, 2016. https://repositorio.ucs.br/handle/11338/1141.

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Os agentes de controle biológico têm recebido grande reconhecimento, e o seu uso tem contribuído como um complemento ou substituição de agroquímicos. No entanto, existem poucos estudos sobre o controle biológico da Pinta Preta dos Citros, causada pelo fungo Guignardia citricarpa, o que impede o seu mercado in natura, além de prejudicar a sua exportação pelo uso intensivo de insumos químicos para controlar este patógeno. Os fungos do gênero Trichoderma são agentes de controle utilizados em todo o mundo contra vários fitopatógenos relevantes. Este estudo visou identificar proteínas extracelulares secretadas por T. atroviride T17 e por T.harzianum T1A, eficazes para o controle de G. citricarpa. Por eletroforese bidimensional (2D) foram obtidos perfis de proteínas secretadas por Trichoderma em meio de glicose (controle) e em meio suplementado com micélio desativado de G. citricarpa. As proteínas foram identificadas por LC-MS/MS mostrando que ambas as espécies secretam proteínas diferentes. Foram identificadas 68 proteínas das 178 diferencialmente expressas por T. harzianum, sendo a maioria relacionada aos mecanismos de biocontrole, mesmo no meio controle. Foi verificado que em contato com o patógeno a expressão de proteínas relacionadas com o metabolismo primário diminui. Por outro lado, Trichoderma atroviride mostrou uma maior expressão de proteínas relacionadas com biocontrole na presença de micélio do patógeno. Nesta espécie identificamos 59 proteínas de 116 diferencialmente expressas, principalmente proteínas relacionadas com a degradação da parede celular: α- manosidase, quitinase, mutanase, glicosidase, endoquitinase e, algumas famílias de glicoside hidrolases. Os resultados indicam que estas espécies apresentam um elevado potencial como agentes de controle de G. citricarpa. Os resultados são pioneiros em detalhar a interação de Trichoderrma com G. citricarpa, por meio da análise do secretoma.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES.
Biological control agents (BCA) have received great recognition, and their use has contributed as a complement or replacement of agrochemicals. However, there are few studies on the biological control of Black spot of citrus, caused by the fungus Guignardia citricarpa, which prevents the market in natura, besides damaging their export by the intensive use of chemical inputs to control this pathogen. Trichoderma fungi are the most applied worldwide BCA against various relevant plant pathogens. The purpose of this study was to identify extracellular proteins secreted by T. atroviride T17 and of T. harzianum T1A, which are effective for the control of G. citricarpa. Bidimensional electrophoresis (2D) allowed obtaining the secreted protein profiles of Trichoderma grown in glucose medium (control) and in medium containing inactivated mycelium of G. citricicarpa. From the 178 differentially expressed proteins by T. harzianum, 68 were identified, most of them related to biocontrol mechanisms, even in the control medium. In the presence of the pathogen, the expression of proteins related to the metabolism decreases. On the other hand, Trichoderma atroviride showed higher expression of proteins related to biocontrol pathogen when grown in the presence of pathogen mycelium, when compared to the control medium. From the 116 differentially expressed proteins, 59 were identified, mainly proteins related to fungi cell wall degradation such as α-mannosidase, chitinase, mutanase, glycosidase, endochitinase and, some families of glycoside hydrolases. The results indicate that these species have a high potential as biocontrol agents of G. citricicarpa. These results are pioneers in to detail the Trichoderrma interaction with G. citricicarpa through the secretome analysis.
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Ben, Amira Maroua. "Etude de la relation mycoparasitaire Trichoderma harzianum avec Fusarium solani chez l’Olivier ; caractérisations moléculaires et fonctionnelles des aquaporines chez Trichoderma harzianum." Thesis, Université Clermont Auvergne‎ (2017-2020), 2018. http://www.theses.fr/2018CLFAC009/document.

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La lutte biologique par utilisation de micro-organismes a indéniablement un potentiel de développement considérable. Dans un contexte multidisciplinaire et fondamental de physio-phytopathologie moléculaire et répondant à d’éminents enjeux appliqués et attendus par les acteurs de la profession oléicole et les consommateurs, nous nous sommes projetés dans l’étude des propriétés intrinsèques d’un agent de biocontrôle fongique, Trichoderma harzianum (souche Ths97) contre l’agent de la fusariose Fusarium solani (souche Fso14), qui sévit sévèrement sur une culture pérenne majeure pour la Tunisie, l’oléiculture. Deux axes de recherche ont été menés. Dans le premier axe, nous avons démontré que Ths97 est un agent de biocontrôle efficace contre la virulence de F. solani Fso14. Cette capacité s’accompagne d’une accumulation des défenses chez le partenaire végétal, des accumulations qui sont d’autant plus fortes quand l’agent bénéfique est en présence du pathogène (événements de priming). De même, des tests in vitro montrent que Ths97développe des activités mycoparasites envers F. solani Fso14, en émettant des structures d’infection classiques tels des enroulements et accolements d’hyphes, des appressoria et des papilles. Quant au second axe d’étude, nous avons étudié la superfamille des perméases Major Intrinsic Proteins (MIP) dans le genre Trichoderma. Cette famille multigénique n’a jamais été étudiée chez un agent fongique hyperparasite. Sept membres MIP sont présents chez T. harzianum, et se classent en 3 sous-groupes, les AQP, les AQGP et les XIP. La modélisation des structures tridimensionnelles et les fonctions putatives de transport pour l’eau et quelques polyols ont été étudiées. Enfin, leurs patrons transcriptionnels ont été suivis chez Ths97 in planta en situation d’antagonisme et in vitro en situation de parasitisme vis-à-vis de Fso14, et montrent que 4 MIP sont exprimées et régulées différentiellement selon que Ths97 est au contact de Fso14 ou pas. Nos travaux ont donc mis en lumière que Ths97 doit être considéré comme un agent biofongicide et biostimulateur de défenses végétales, puis que les MIP seraient impliqués dans les relations trophiques que met en place T. harzianum avec son environnement. Ces données devraient intégrer le développement de procédés plus efficaces et/ou plus durables pour la protection des cultures d’oliviers en Tunisie ainsi qu’à travers le monde
Biological disease control through the use of microorganisms has a great potential for future use in integrated pest management. In a multidisciplinary and fundamental context of molecular physio-phytopathology and to provide solutions for the actors in the olive profession and the consumers, we have been studying the activity of a fungal biocontrol agent, Trichoderma harzianum (strain Ths97) against the olive tree pathogen Fusarium solani (strain Fso14), which causes major problems for olive production in Tunisia and elsewhere. The project consists of two parts. In the first part, we have demonstrated that Ths97 is a biocontrol agent effective against the F. solani Fso14 pathogen. Induction of plant defence responses by Ths97 was shown to be partly responsible for the biocontrol effect. In vitro tests further showed that Ths97 develops mycoparasitic activities towards F. solani Fso14, by forming infection structures such as hyphae windings and wedges, appressoria and papillae. In the second part of the study, we investigated the Major Intrinsic Proteins (MIP) superfamily in the Trichoderma genus. This multigenic family has never been investigated in a hyperparasitic fungal species. Seven MIP members are present in T. harzianum, and are classified into 3 subgroups: AQP, AQGP and XIP. Their three-dimensional structures and their putative involvement in transport of water and certain polyols have been examined. Finally, their transcription profiles were monitored in Ths97 in planta in antagonistic situations and in vitro in a parasitic situation with Fso14 and show that 4 MIP are expressed and regulated differentially during the interaction. Our work has shown that Ths97 must be considered as a biological control agent and biostimulator of plant defences, and that MIPs are involved in the trophic relationships between T. harzianum and the environment. These data contributes to the further development of T. harzianum as an efficient biocontrol agent for sustainable protection of olive trees in Tunisia and around the world
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19

Hajji, Mohamed El. "Trichorzianines A VII et A IIIc, peptides antifongiques de Trichoderma harzianum." Paris 6, 1986. http://www.theses.fr/1986PA066467.

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20

Chahal, Parminder Singh. "Cellulase production from lignocellulosic materials by Trichoderma reesei." Thesis, University of Ottawa (Canada), 1987. http://hdl.handle.net/10393/5536.

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21

Narra, Hema Prasad. "Genomics and biocontrol efficacy in the genus Trichoderma." Thesis, University of Reading, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553099.

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Forty-two Trichoderma isolates were characterized using various molecular and morphological approaches. Morphological identification using conidial and growth characters did not provide sufficient information for reliable species identification. ITS sequences clearly separated all the biocontrol isolates from the pathogenic isolates of T. harzianum. Endochitinase gene sequence based analysis of the isolates revealed similar pattern of grouping to that of ITS except for two isolates (Tv 2 and TRC 1), whereas beta-tubulin gene phylogeny resulted in a better resolution of the isolates belonging to the section Pachybasium. Isolates belonging to Trichoderma sections Trichoderma and Longibrachiatum grouped similarly when analyzed by ITS, endochitinase and beta-tubulin sequences. Though morphological and ITS sequence analysis differentiated pathogenic isolates from biocontrol isolates of Trichoderma, the endochitinase and beta-tubulin genes did not, presumably due to the functional nature of these genes in the fungus. Significant differences were observed in biocontrol efficacy when Trichoderma isolates were applied against Fusarium culmorum in wheat. No correlation was observed between biocontrol efficacy and phylogenetic relationship of the isolates. Significant growth enhancement was observed when Trichoderma was applied to the soil. Antagonistic mixtures performed poorly when compared to individual application of the biocontrol isolates. Genetic diversity inferred from ISSR data revealed a high level of inter- and intra-specific variability. All isolates clustered into 27 different groups distributed into six clusters. Sequence variations observed in endochitinase gene and ITS regions were successfully used for development of strain- and species-specific primers with a very high level of specificity and sensitivity of down to l0pg/μ1 of DNA concentration in conventional end-point PCR. The study reveals the efficiency of molecular markers for species identification and explores the genetic diversity among the isolates and their impact on biocontrol efficacy.
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Deane, Eddie Edward. "Trichoderma harzianum chitinase : biochemical, molecular and biocontrol properties." Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261167.

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23

Carter, Jonathan Philip. "Population biology of Trichoderma spp. used as inoculants." Thesis, University of Reading, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329046.

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24

Ribeiro, Ana Paula dos Santos. "Produção de quitinases por fermentação por trichoderma sp." [s.n.], 2000. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267564.

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Orientador: Telma Teixeira Franco
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Enzimas quitinolíticas, como as quitinases, presentes nos reinos animal, vegetal e fúngico, constituem um importante grupo de enzimas associadas com o metabolismo e degradação de substratos insolúveis como a quitina. Neste trabalho foi realizado um estudo para a verificação da influência da fonte de carbono livre (glicose e lactose) e das condições de cultivo (agitação e pH) na produção de quitinase da linhagem de Trichoderma sp. T 6. As fermentações foram realizadas a 27°C, retirando-se amostras a cada 12 horas ao longo de 72 horas de fermentação para determinação da atividade quitinolítica, proteolítica, açúcares redutores e pH. Foi avaliado o efeito das três variáveis sobre a produção de quitinase por Trichoderma sp. T6. As melhores condições encontradas para o meio contendo glicose, foram agitação de 200 rprn, pH 6,0,0,3% de glicose atingindo uma média de produção de enzima de 1,92 U/rnL. Para os meios de cultura contendo lactose, a máxima produção de quitinase se deu nos ensaios 5,6 e 7 (0,5% lactose) com 0,76,0,75 e 0,85 U/rnL, respectivamente. Foi observada formação de proteases desde o início da fermentação nos ensaios contendo lactose. A hidrólise enzimática com o caldo bruto do ensaio de máxima produção quitinolítica foi acompanhada por 8 horas produzindo dois oligossacarídeos predominantes, o mono e o di-acetilquitobiose
Abstract: Chitynolytics enzymes, as chitinases, constitute an important group of enzymes related with metabolism and degradation of insoluble substract as chitin present in animal, plants and fungi. In this work studies of carbon source (glucose and lactose) and cultivation conditions (agitation and pH) to produce chitinase by Trichoderma sp. T6 were carried out. The effect of carbon source, agitation and pH upon chitinase production by Trichockrma sp. T6 was investigated. Fermentations were performed at 27°C, and samples were withdraw every 12 hours during 72 hours of fermentation in order to assay both chitinolytic and proteolytic activity, as well as reducing sugar and pH. The optimal conditions for chitinase production found in glucose medium were 200 rpm (agitation), 6,0 (pH) and 0,3% (glucose) achieving an average value of 1,92 V/roL. Liquid culture medium with lactose showed maximum production of chitinase at 5th, 6th and 7th experiments (0,5% lactose) with 0,76, 0,75 and 0,85 V/roL, respectively. lt was observed that proteases were formed at beginning of fermentation in the experiments using lactose. Chitin hydrolysis by the raw broth of maximum chitinolytic activity was followed for 8 hours and the two predominant oligosaccharides, were mono and di-acetylchitobiose, respectively
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química
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Santos, Karina Roterdanny Araújo dos. "Análise da tolerância á resistência em Trichoderma harzianum." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7940.

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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
The presence of heavy metals in the soil has increased, causing many problems of an agricultural nature. Trichoderma are a species which is among the most well know and used biocontrol agents wordwide, as well as possessing qualities such tha parasitism and antibiosis, they have great resistance to metals and can also absorb them. Therefore, it is necessary for more detailed studies of the resistance of this fungus to metals and to research further the processes involved. In this work, we aimed to better understand the tolerance of T. harzianum to aluminum chloride, though a series of experiments performed in BDA, MEX e MYG, as well Bradford tests for quantification of proteins. In addition, we evaluated the gene response to metal stress through the sequencing RNA samples obtained when the fungus was created in BDA medium and submitted to concentrations of 1.5 and 3.0 mg / mL of aluminum chloride, 1.5 mg / mL, the fungus showed significant inhibition. It was observed that T. harzianum showed higher mycelial growth when grown in BDA medium compared to MEX and MYG, presenting levels of protein secretion inversely proportional to increasing concentrations of aluminum. The amount of transcriptionspecific factors of the stress response was increased, as well as the induction of genes involved in G-mediated cell signaling and increase in genes involved in vacuolar transport and carrier proteins. A repression of genes encoding proteins associated with cellular processes important for the growth of T. harzianum was also observed. These results show that T. harzianum is resistant to aluminum since it is able to tolerate and absorb large concentrations of this metal, which is commonly harmful to agriculture.
A presença de metais pesados no solo tem sido cada vez mais frequente, aumentando dentre vários problemas, os de cunho agrícola. Espécies de Trichoderma estão entre os agentes de biocontrole mais conhecidos e empregados mundialmente, pois além de possuir ações como parasitismo e antibiose, possui grande resistência a metais, podendo também absorvê-los. Sendo assim, faz-se necessário, estudos mais aprofundados a cerca da resistência desse fungo a metais, envolvendo pesquisas que esclareçam melhor os processos envolvidos. Neste trabalho, objetivamos melhor compreensão a cerca da tolerância de Trichoderma harzianum ao alumínio, através do seu crescimento em diferentes meios de cultura com variadas concentrações do metal. Avaliamos também a secreção de proteínas quando o fungo crescia na presença de alumínio. Além disso, analisamos a resposta gênica ao estresse pelo metal através do sequenciamento de amostras de RNA obtidas quando o fungo foi crescido em meio BDA e submetido às concentrações de 1,5 e 3,0 mg/mL de cloreto de alumínio. Foi possível constatar que T. harzianum apresenta maior crescimento micelial quando crescido em meio BDA, comparado aos meios MEX e MYG, apresentando níveis de secreção de proteínas inversamente proporcionais às concentrações crescentes de alumínio. Foi observada alteração na expressão gênica através do aumento da quantidade de determinados fatores de transcrição de resposta a estresse, além da indução de genes envolvidos em sinalização celular mediada por proteína G e aumento em genes envolvidos com transporte vacuolar e proteínas transportadoras. A repressão de genes que codificam proteínas associadas a processos celulares importantes para o crescimento de T. harzianum também foi observada. No entanto, nossos resultados evidenciam que T. harzianum apresenta resistência significativa ao alumínio, uma vez que se mostra capaz de tolerar e absorver grandes concentrações deste metal, comumente prejudicial à agricultura.
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26

Carvalho, Filho Magno Rodrigues de. "Trichoderma spp. como agentes de biocontrole de Cylindrocladium." reponame:Repositório Institucional da UnB, 2008. http://repositorio.unb.br/handle/10482/1818.

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Fitopatologia, 2008.
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Um breve levantamento de patógenos foliares em área de produção comercial de mudas de eucalipto em um viveiro comercial de eucalipto no município de Luziânia (GO) revelou a ocorrência de cinco patógenos: C. scoparium, Pleospora sp., Hainesia sp., Pestalotiopsis sp. e Rhizoctonia solani (Capítulo I). Dentre esses patógenos de eucalipto (Eucalyptus sp.), destaca-se a mancha foliar causada pelo Cylindrocladium spp. Morgam (Teleomorfo: Calonectria sp. De Not). Esta enfermidade é especialmente importante em viveiros para a produção de mudas de eucaliptos, especialmente na clonagem de híbridos da espécie. O controle da doença tem sido baseado, principalmente, no tratamento das plantas com a aplicação de fungicidas em todos os estágios da clonagem do eucalipto. No capitulo II, foram testados os meios de cultura líquidas SG (Sacarose-Glicose), BD (Batata-Dextrose) e SDY (Extrato de levedura) para a produção de esporos de C. scoparium. O meio liquido SG possibilitou a produção de conídios dos dois isolados do patógeno que se mostraram infectivos em folhas de eucalipto. Para elaborar um programa de controle biológico contra doenças de plantas, é necessária seleção de antagonistas bem adaptados com alto grau de controle contra os fitopatógenos e, preferencialmente, que promovam o crescimento e enraizamento das miniestacas. Neste trabalho foram selecionados cinco isolados de Trichoderma por meio de testes in vitro e in vivo, foi avaliado o controle biológico de dois isolados de Cylindrocladium scoparium em folhas destacadas, a habilidade dos isolados do antagonista como produtores do hormônio de crescimento ácido Indolacético (AIA) e quanto à capacidade de colonização endofítica, em mudas de clones híbridos (G-100) de eucalipto. Estudou-se a promoção de crescimento e enraizamento de mudas de Eucalyptus urophillla obtidas por sementes e no híbrido G-100 (Eucalyptus grandis x Eucalyptus urophilla) obtido por clonagem. Também foi estudada a capacidade de esporulação dos isolados de Trichoderma em dois substratos sólidos: grãos de arroz parboilizado de milheto. Os experimentos in vitro consistiram em pareamento de colônias e exposição do patógeno a metabólitos voláteis e não voláteis produzidos por Trichoderma spp. Observaram-se alterações morfológicas em hifas e inibição no crescimento micelial de C. scoparium. Em folhas destacadas de eucalipto, os cinco isolados de Trichoderma conferiram proteção contra a doença, sendo que o isolado CEN 517 de C. scoparium mostrou-se mais agressivo comparado ao CEN 494 de C. scoparium, quando quantificados os níveis de incidência da mancha foliar. Os dados obtidos na esporulação dos antagonistas em arroz parboilizado e milheto revelaram grande variação entre esses isolados. O isolado CEN 262 (T. harzianum) apresentou maior produção de esporos em ambos os substratos, aos 07 e 11 dias de incubação (capítulo III). Nos experimentos para a avaliação da promoção de crescimento,utilizando cinco isolados de Trichoderma selecionados nos ensaios de laboratório, o isolado CEN 262 apresentou um incremento significativo da matéria seca das raízes, da parte aérea e da altura das mudas. In vitro, constatou-se a produção de AIA pelos seguintes isolados: CEN 209, CEN 500 e CEN 262. O isolado CEN 262 apresentou concentração do hormônio 19 vezes maior que o CEN 209. Os isolados CEN 162, CEN 262, CEN 498 demonstraram capacidade de colonizar raízes de eucalipto (capítulo IV). _________________________________________________________________________________ ABSTRACT
A brief survey of leaf pathogens in a commercial production area of eucalyptus seedlings in a commercial nursery in the municipality of Luziânia (GO) showed the occurrence of five pathogens: C. scoparium, Pleospora sp., Hainesia sp., Pestalotiopsis sp. and Rhizoctonia solani (Chapter I). Among these pathogens of eucalyptus (Eucalyptus spp.), leaf spot caused by Cylindrocladium spp. Morgam (Teleomorph: Calonectria sp. de Not) stands out. This disease is especially important in nurseries that produce eucalyptus seedlings, especially in the cloning of hybrid species. Control of the disease has been based mainly on treating plants with fungicides at all stages of eucalyptus cloning. In Chapter II, liquid culture media SG (Sucrose-Glucose), BD (Potato-Dextrose) and SDY (Yeast extract) were tested to produce spores of C. scoparium. The SG liquid medium enabled the production of conidia of two pathogen isolates, which were showed to be infective in eucalyptus leaves. To draw up a biological control program against plant diseases, it is necessary and appropriate to select well adapted antagonists with a high degree of control against the plant pathogens and, preferably, to promote growth and rooting of the minicuttings. In this study five isolates of Trichoderma were selected through in vitro and in vivo tests. The biological control of two isolates of Cylindrocladium scoparium in detached leaves was evaluated, as well as the ability of the antagonist isolates to produce indoleacetic acid (IAA) growth hormone and for endophytic colonization in seedlings of hybrid clones (G-100) of eucalyptus. The promotion of plant and root growth was studied in Eucalyptus urophillla seedlings obtained from seeds and in the hybrid G-100 (Eucalyptus urophilla x Eucalyptus grandis) obtained by cloning. The capacity of Trichoderma isolates to sporulate in two solid substrates, grains of parboiled rice and millet, was also studied. The in vitro experiments consisted of pairing colonies and exposing the pathogen to volatile and non-volatile metabolites produced by Trichoderma spp. Morphological changes were observed in hyphae and inhibition of micelial growth of C. scoparium. On detached eucalyptus leaves, the five Trichoderma isolates gave protection against the disease, and isolate CEN 517 of C. scoparium proved to be more aggressive than CEN 494 of C. scoparium, when the levels of incidence of leaf spot were quantified.The results obtained for sporulation of antagonists in grains of parboiled rice and millet showed great variation between these isolates. The isolate CEN 262 (T. harzianum) showed higher production of spores in both substrates, at 07 and 11 days of incubation (Chapter III).In experiments to evaluate growth promotion, using five isolates of Trichoderma selected in laboratory tests, isolate CEN 262 (Trichoderma harzianum) showed a significant increase in dry roots, shoots and height of the seedlings. In vitro, the production of IAA was observed in the following isolates: CEN 209, CEN 500 and CEN 262. Isolate CEN 262 presented concentration of the hormone that was 19 times greater than that of CEN 209. CEN 162, CEN 262 and CEN 498 isolates demonstrated capacity to colonize roots of eucalyptus (Chapter IV).
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27

Cochet-Giraud, Nelly. "Les Cellulases de Trichoderma reesei production et application /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37604010n.

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28

Serrano, Carreon Leobardo. "Etude sur le métabolisme des lipides et la production de 6-pentyl-alpha-pyrone par deux espèces du genre trichoderma." Dijon, 1992. http://www.theses.fr/1992DIJOS050.

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Les mécanismes impliqués dans la biosynthèse des lactones à cycle insaturé sont peu connus. Le métabolisme des lipides dans la production de lactones à cycle saturé par voie microbiologique a été, par contre, souvent cité comme l'étape clé du processus de biogenèse. Ainsi, l'étude du métabolisme des lipides et de sa relation possible avec la biosynthèse de 6-pentyl-alpha-pyrone par deux champignons filamenteux du genre trichoderma a été le sujet de ces recherches. L'influence de la nature des sources de carbone et d'azote a été étudiée en vue de stimuler l'accumulation des lipides chez trichoderma harzianum et trichoderma viride. Malgré la capacité de ces champignons à accumuler des lipides, la biosynthèse de 6-pentyl-alpha-pyrone reste limitée. Cette faible production n'est pas due a une retro inhibition de la biosynthèse de la lactone par elle-même. Des expériences sur des cultures de trichoderma sp. Avec l'acide (1-14c) linoléique, ou l'acide (u-14c) linoléique, ou du (5-14c) mevalonate de sodium ont été réalisées. D'après les résultats obtenus la 6-pentyl-alpha-pyrone proviendrait du métabolisme de l'acide gras et la beta-oxydation des acides gras serait à l'origine de la formation de la pyrone par ces microorganismes. Trichoderma sp. Peut produire, a partir du ricinoléate de méthyle, quatre fois plus de 6-pentyl-alpha-pyrone que par culture sur un milieu d'accumulation des lipides à base de glucose. A un degré moindre le même phénomène est observé sur oléate et lin oléate de methyle. Ces résultats soulignent l'importance de l'hydroxyle sur la molécule d'acide gras. Un schéma de biosynthèse est proposé pour expliquer la formation de 6-pentyl-alpha-pyrone à partir du ricinoleate de méthyle
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29

Trocoli, Rafael Oliva. "Trichoderma, biodiversidade e aplicação no controle da fusariose do abacaxizeiro: caracterização molecular de agentes de biocontrole (Trichoderma spp.) de Fusarium guttiforme." reponame:Repositório Institucional da UFRB, 2013. http://www.repositorio.ufrb.edu.br/handle/123456789/879.

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O abacaxizeiro (Ananas comosus) representa uma das poucas alternativas agrícolas de geração de renda para agricultores familiares do semiárido do Nordeste brasileiro. A fusariose do abacaxizeiro, doença causada por Fusarium guttiforme (Fgt), ocasiona elevadas perdas na produção, sendo este o principal fator limitante para a cultura. O uso de fungos do gênero Trichoderma, que têm demonstrado resultados robustos no controle de vários fitopatógenos constitui uma alternativa de controle. Todavia, pesquisas dessa natureza com foco no biocontrole de Fgt são escassas. Neste estudo, Trichoderma spp. foram isolados de espécies vegetais da Caatinga. Os isolados com maior potencial de biocontrole de Fgt foram selecionados por meio de testes in vitro e em casa de vegetação (Capítulo 1). Em campo, os isolados TC77 (953,30 gramas), TC26 (951,05 g) e TC36 (927,23g) apresentaram os maiores índices de controle da doença expresso em peso médio de fruto (Capítulo 2). Análises BOX-PCR dos isolados de Trichoderma spp. originaram 14 grupos genéticos (Grg), os quais foram submetidos a testes de biocontrole de Fgt in vitro. Nestes, o Grg 3 (TC09), Grg 9 (TC10) e Grg 5 (TC14) demonstraram os melhores desempenhos na redução da colonização do patógeno. Sequências de fragmentos da região ITS e do gene TEF1-α de cada isolado foram usadas nas análises filogenéticas. Os isolados TC26 e TC36 (Grg10) foram identificados como T. koningiopsis, e o isolado TC77 (Grg09) como T. atroviride. Independente do potencial de biocontrole, outras cinco espécies foram identificadas entre os isolados estudados: T. virens; T. longibrachiatum; T. dorotheae; T. cremeum; e T. stromaticum. Prováveis novas espécies foram representadas pelos isolados TC06, TC23, TC26 e TC93 (Capítulo 3). Futuramente, formulações desses isolados poderão ser usadas em escala comercial, o que justifica novos estudos com foco na sua precisa identificação e descrição de novas espécies
Tese submetida ao Colegiado de Curso de Pós-Graduação em Ciências Agrárias da Universidade Federal do Recôncavo da Bahia como requisito para obtenção do Grau de Doutor em Ciências Agrárias.
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30

Curach, Natalie Claire. "An investigation into the hex1 gene and gene promoter for the enhancement of protein production in Trichoderma reesei." Phd thesis, Australia : Macquarie University, 2005. http://hdl.handle.net/1959.14/71199.

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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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31

Poggi-Parodi, Dante. "Une approche de biologie systémique pour développer des souches industrielles performantes de Trichoderma reesei." Electronic Thesis or Diss., Paris 6, 2014. http://www.theses.fr/2014PA066721.

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La compréhension de la régulation de la synthèse et sécrétion de cellulases dans le champignon Trichoderma reesei a fortement évolué ces dernières années. Cependant, le coût de production de cellulases reste encore un des principaux problèmes pour la production de bioéthanol à partir de lignocellulose. C’est dans ce contexte que mon projet de thèse s’inscrit, dans l’amélioration de la production de cellulases de T. reesei et son adaptation aux conditions industrielles. D’abord, nous avons réalisé une analyse du transcriptome sur une lignée de souches améliorées dans des conditions proches du procède industrielle avec lactose comme inducteur. Cette étude nous a permis de trouver des gènes spécifiquement régulés dans la souche plus performante, probablement impliqués dans sa grande capacité de production de cellulases. Dans un deuxième temps, nous avons identifié parmi les gènes régulés du transcriptome lesquels impliquées dans la production de cellulases. A cet effet, des souches mutées ont été construites et leur phénotype évalué. Trois de ces gènes mutés ont affecté la production de cellulase et leur fonction ont dévoilé des nouvelles mécanismes régules. Finalement, nous avons exploré les différences d’expression lorsque nous utilisons un hydrolysat de lignocellulose comme inducteur de cellulases à la place du lactose. Une étude du transcriptome dans ces conditions, nous a permis de caractériser les différences de régulation des gènes entre ces inducteurs. En outre, nous avons identifié un groupe des gènes probablement impliqué dans la détoxification qui peuvent être utilisés dans le futur pour développer une souche résistante aux inhibiteurs
A lot of progress had been done in recent years to understand the regulation of synthesis and secretion of cellulases in the fungus Trichoderma reesei. However, the production cost of cellulases still remains one of the most important limiting steps in the production of bioethanol from lignocellulose. It is in this context that my PhD project has been developed: to genetic engineering T. reesei strains to increase its cellulase production and its adaptation to industrial conditions. First, we conducted a transcriptome analysis to an improved lineage of industrial strains during cellulase production following conditions close to the industrial process (lactose as inducer and fed-batch culture in bioreactor). We found specifically regulated genes for the most performant strain, possibly involved in its high cellulase production capacity. Then, we identified which regulated genes from transcriptome were involved in cellulase production. For this purpose mutated strains for highly regulated genes were constructed and their phenotype assessed. Three mutated genes showed to impact cellulase production and their function gave us an insight into new mechanisms being regulated. Finally, we explored the expression differences when we used a lignocellulose hydrolysate as cellulases inducer instead of lactose. A transcriptomic study of cellulases production on lignocellulose hydrolysates and lactose, allowed us to characterize the differences in regulated genes between these inducers. In addition, a group of genes probably related to detoxification was identified and could be used in the future to develop an inhibitor resistant strain
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Pereira, Beatriz Merchel Piovesan. "Produção de enzimas por fungo filamentoso para hidrólise de material lignocelulósico." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266713.

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Orientadores: Aline Carvalho da Costa, José Geraldo da Cruz Pradella
Dissertação (mestrado) - Universidade Estadual de Campoinas, Faculdade de Engenharia Química
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Resumo: A produção de enzimas lignocelulolíticas por Trichoderma reesei RUT-C30 foi otimizada em frascos agitados e bioreatores de 0,5 e 3L visando maximizar os títulos enzimáticos e produtividade volumétrica. Para isso, foram testadas como fontes de carbono (1% m/v) bagaço de cana-de-açúcar pré-tratado por processo hidrotérmico (BH) ou por explosão a vapor, com (BED) e sem (BEX) deslignificação, em meio contendo proteose peptona, tween 80 e solução salina. Celulose comercial Celufloc200 (CE) foi testada para comparação. Maior produção de enzimas celulolíticas foi obtida com a utilização de BED (1,38 ± 0,11 FPU/mL) quando em comparação com CE (0,78 ± 0,14 FPU/mL) em frascos agitados, sendo esse material utilizado como fonte de carbono nos demais ensaios. A produção de hemicelulases (xilanases) foi similar para os dois meios (em U/mL): 18,03 ± 1,56 para BED e 20,04 ± 1,50 para CE. A variação da concentração da solução salina, da fonte de carbono e dos nutrientes permitiu aumento da produção de enzimas celulolíticas para 1,89 ± 0,12 (meio com o dobro de solução salina) e 2,73 ± 0,09 (meio com 2% m/v de BED e nutrientes proporcionais) em frascos agitados. A suplementação da fonte de carbono com farelo de soja, sacarose, licor de pré-tratamento, lactose e glicerol foi estudada e farelo de soja foi selecionado como suplemento do meio. A elaboração de um meio de mistura contendo o dobro de solução salina, farelo de soja e nutrientes proporcionais à concentração da fonte de carbono (meio MIX) permitiu o aumento da produção de enzimas para, em FPU/mL: 3,33 ± 0,10 (MIX15: contém 1,5% m/v de BED), 3,78 ± 0,33 (MIX20) e 3,67 ± 0,34 (MIX30) em frascos agitados. As atividades de xilanases foram superiores a 130 U/Ml utilizando os meios de mistura. Em bioreator de 3L a produção de enzimas celulolíticas utilizando o meio MIX15 atingiu 2,29 ± 0,20 FPU/mL. Para o meio padrão (BED 1% m/v) o pico de atividade obtido foi de 1,14 ± 0,32 FPU/mL. O aumento da concentração da fonte de carbono em bioreator para 3% (m/v) a partir do meio MIX15 resultou no aumento da atividade celulolítica para 4,20 ± 0,34 FPU/mL. Os picos de atividade de xilanases atingiram valores superiores a 180 U/mL em bioreator. O desempenho do coquetel enzimático produzido no meio MIX15 foi avaliado na hidrólise de BED e BH, e comparado ao coquetel produzido no meio padrão e a um coquetel comercialmente disponível (Sigma). Os valores de conversão de celulose em glicose foram superiores para o coquetel MIX15 em relação aos demais coquetéis ao se utilizar 3 ou 5% de sólidos, com ou sem adição de beta-glucosidase comercial (Novozym 188)
Abstract: The production of lignocellulolytic enzymes by Trichoderma reesei RUT-C30 was optimized in shake flasks and 0.5 and 3L bioreactors to maximize the enzymatic titles and volumetric productivity. The carbon sources considered were sugar cane bagasse (1% w/v) pretreated by the hydrothermal process (BH) or steam explosion, with (BED) and without (BEX) delignification. The medium contained proteose peptone, Tween 80 and saline solution. Commercial cellulose Celufloc200 (CE) was used for comparison. Increased production of cellulolytic enzymes in flasks was obtained with BED as carbon source (1.38 ± 0.11 FPU / ml) when compared to CE (0.78 ± 0.14 FPU / ml), and this material was selected as carbon source for further studies. The production of hemicellulases (xylanases) was similar for the two carbon sources (U / mL): 18.03 ± 1.56 with BED and 20.04 ± 1.50 with CE. Variation of the concentration of the salt solution, carbon source and nutrients led to an increased production of cellulolytic enzymes: 1.89 ± 0.12 (medium with doubled saline solution concentration) and 2.73 ± 0.09 (medium with 2% w/v BED and nutrients proportional to the carbon source) in shake flasks. Supplementation of the carbon source with soybean meal, sucrose, pretreatment liquor, lactose and glycerol was studied and soybean meal has been selected as supplement. The preparation of a mixture medium containing doubled saline solution, soybean meal and nutrients proportional to the concentration of the carbon source allowed increasing the production of enzymes for (in FPU / ml): 3.33 ± 0.10 (MIX15 - containing 1.5% w/v BED) , 3.78 ± 0.33 (MIX20) and 3.67 ± 0.34 (MIX30) in shake flasks. Xylanase activities were higher than 130 U/mL. In a 3L bioreactor, production of cellulolytic enzymes using MIX15 medium reached 2.29 ± 0.20 FPU / mL. For the standard medium (BED 1% w/v) the peak activity was 1.14 ± 0.32 FPU / mL. Increasing the concentration of the carbon source in the bioreactor to 3% w/v starting from MIX15 resulted in a cellulolytic activity of 4.20 ± 0.34 FPU / mL. Xylanase activity reached values higher than 180 U/mL in the bioreactor. The performance of the enzyme cocktail produced in MIX15 medium was evaluated for the hydrolysis of BED and BH, and compared to the cocktail produced in the standard medium and to a cocktail commercially available (Sigma). The values of conversion of cellulose to glucose were higher for the cocktail MIX15 compared to the other cocktails when using 3 or 5% solids, with or without adding commercial beta-glucosidase (Novozym 188)
Mestrado
Desenvolvimento de Processos Químicos
Mestra em Engenharia Química
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33

Melo, Laryssa da Silva. "Identificação molecular e produção de enzimas celulolíticas por Trichoderma spp." Universidade Federal do Amazonas, 2009. http://tede.ufam.edu.br/handle/tede/2254.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Trichoderma are anamorphic fungi belonging to the class of Hifomicetos, also called imperfect fungi, or asexual conidial and whose gender Hypocrea teleomorph. They are free-living fungi, distributed throughout the world and found in different soil temperatures, especially those containing organic matter. Usually are not considered important human pathogens, but there are some reports indicating occasional pathogenicity of some species. Its easy handling and in vitro, stability and viability of colonies preserved this kind are a big target for biotechnology research. Because of these characteristics were isolated Trichoderma from plant Victoria amazonica, Rollinia sp. Murraya paniculata and Strychnos cogens; wood Scleronema micranthum, known as cardeiro; jatoba (Hymenaea courbaril), land of cubiu culture (Solanum sessiliflorum) and Indian black earth, in order to identify the molecular biology, the species level, such isolates and to assess their ability to produce cellulolytic enzymes. Of the 30 lines obtained were cultured spore, which were preserved in mineral oil, Castellani and method in 10% glycerol. From the suspension in glycerol, each sample was inoculated in 20ml of 10μL BD and cultivated 26oC, 100 rpm for 40:00 h. Next was extracted genomic DNA, performed PCR of specific regions of the ITS-1 and ITS-2 ribosomal DNA sequencing and subsequently. For the production of enzymes, the isolates were first grown in induction medium. Were inoculated 10μL of spore solution (glycerol 10%) in 50 mL of solution Manachini where the substratum was used to carboxymethylcellulose. The fungi were incubated at 27 ° C, 120 rpm for 120 hours. The dosage of CMCase was performed using the method of acid Dinitrosalicílico. For the determination of β-glucosidase was used p-nitrophenyl-β-D-glucopyranoside (PNPG) as substrate for the enzyme. The total protein concentration was determined by the Bradford method, using the reagent concentrate commercial Bio-RadTM and bovine serum albumin (ASB) as standard. The result of molecular identification of the first 13 samples revealed the species: T. harzianum, T. koningii, T. asperellum, T. viride, T. ovaslisporum, T. hamatum, T. piluliferum and T. koningiopsis, with a percentage between 96 and 99% identity and 100% reliability. The results indicated CMCase enzyme to low values, less than 0.100 U / mL with the exception of T. koningii (MPCE 10 3.2), T. harzianum (MPCE 2 2.2a), both isolates of M. paniculata, and isolate 1437 identified as Trichoderma sp., from Indian black earth, which showed slightly higher levels of 0.112 and 0.103 and 0.105 U / mL, respectively. For β-glucosidase, the results showed high activity in the vast majority of isolates with emphasis on T. harzianum MPCE 3 3.1 (10.45 U / mL) and T. piluliferum Vrc 2 3.2 (9.71 U / mL). All isolates produced protein in culture medium containing carboxymethylcellulose as substrate inducer
Trichoderma são fungos anamórficos pertencentes à classe dos hifomicetos, também chamados fungos imperfeitos, assexuais ou conidiais e que têm como teleomorfo o gênero Hypocrea. São fungos de vida livre, distribuídos em todo o mundo e encontrados em solos de diversas temperaturas, especialmente naqueles que contém matéria orgânica. Geralmente não são considerados importantes patógenos humanos, mas existem alguns relatos indicando patogenicidade ocasional em algumas espécies. Sua fácil manipulação e cultivo in vitro, estabilidade e viabilidade das colônias preservadas, fazem desse gênero um grande alvo para as pesquisas biotecnológicas. Por tais características, foram isolados Trichoderma das plantas Victoria amazonica, Rollinia sp., Murraya paniculata e Strychnos cogens; da madeira Scleronema micranthum, conhecida como cardeiro; de jatobá (Hymenaea courbaril), do solo de cultura de cubiu (Solanum sessiliflorum) e de terra preta de índio, com o objetivo de identificar, pela biologia molecular, em nível de espécie, tais isolados, bem como avaliar sua capacidade de produção de enzimas celulolíticas. Das 30 linhagens obtidas foram realizadas culturas monospóricas, as quais foram preservadas em óleo mineral, método Castellani e em glicerol 10%. A partir da suspensão em glicerol, de cada amostra foi inoculado 10μL em 20mL de BD e cultivado a 26oC, a 100 rpm por 40:00h. Em seguida foi extraído o DNA genômico, deste realizada a PCR específica para as regiões ITS-1 e ITS-2 do DNA ribossômico e posteriormente o sequenciamento. Para a produção de enzimas, os isolados foram previamente cultivados em meio indutor. Foram inoculados 10μL da solução de esporos (Glicerol 10%) em 50mL de solução de Manachini onde o substrato indutor utilizado foi a carboximetilcelulose. Os fungos foram incubados a 27°C, 120 rpm durante 120 horas. A dosagem de CMCase foi efetuada com base no método do Ácido Dinitrosalicílico. Para a dosagem de β-glucosidase foi utilizado o pnitrofenil- β-D-Glucopiranosídeo (pNPG) como substrato para a enzima. A concentração de proteínas totais foi determinada pelo método de Bradford, utilizando-se o reagente concentrado comercial da Bio-RadTM e albumina de soro bovino (ASB), como padrão. O resultado da identificação molecular das primeiras 13 amostras nos revelaram as espécies: T. harzianum, T. koningii, T. asperellum, T. viride, T. ovaslisporum, T. hamatum, T. piluliferum e T. koningiopsis, com um percentual entre 96 e 99% de identidade e 100% de confiabilidade. Os resultados enzimáticos para CMCase indicaram valores baixos, inferiores a 0,100 U/mL com exceção de T. koningii (MPCe 10 3.2), T. harzianum (MPCe 2 2.2a), ambos isolados de M. paniculata, e o isolado 1437 identificado como Trichoderma sp., proveniente de terra preta de índio, que apresentaram valores um pouco mais altos de 0,112 e 0,103 e 0,105 U/mL, respectivamente. Para β-glucosidase, os resultados apresentados mostraram alta atividade na grande maioria dos isolados com destaque para T. harzianum MPCe 3 3.1(10,45U/mL) e T. piluliferum Vrc 2 3.2 (9,71 U/mL). Todos os isolados produziram proteínas em meio de cultura contendo carboximetilcelulose como substrato indutor
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34

Souza, Bárbara Lizandra Perini de. "Fusão de protoplastos entre Penicillium echinulatum e Trichoderma harzianum para obtenção de variabilidade visando a produção de celulases." reponame:Repositório Institucional da UCS, 2007. https://repositorio.ucs.br/handle/11338/881.

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O estudo de fungos celulolíticos tem-se mostrado relevante, tendo em vista o interesse econômico do complexo celulases, especialmente na indústria têxtil e, mais recentemente, para propósitos energéticos. No presente trabalho, a fusão de protoplastos foi utilizada para combinar genótipos de mutantes parcialmente desreprimidos para produção de celulases de Penicillium echinulatum (9A02S1B9) e richoderma harzianum (AS5CH3), utilizando a técnica do doador morto, buscando-se obter recombinantes com maior produção de celulases. Nesta estratégia, ambas as linhagens tiveram seu micélio tratado com Glucanex 0,01 g/mL, para quebra da parede celular. Os protoplastos resultantes da linhagem portadora de marca de resistência ao benomil (9A02S1B9) foram inativados por calor (técnica do doador morto) de 60oC antes da etapa de fusão, a qual após foi induzida por PEG4000 e Ca2+, com protoplastos da linhagem sensível ao benomil (AS5CH3). A partir de um produto de fusão, foram selecionados 24 sub-clones, após estratégias de estabilização e seleção para precocidade e eficiência na formação de halo de hidrólise de celulose em placas de Petri. Os produtos de fusão apresentaram morfologia e esporulação semelhantes a um dos parentais, sendo treze semelhantes à Penicillium, nove semelhantes à Trichoderma e dois mostrando formas alteradas. Os produtos de fusão que segregaram para morfologia de T. harzianum apresentaram a característica de resistência ao benomil, sendo capazes de crescer e esporular em meios contendo até 100 μg/mL deste inibidor. A morfologia, o perfil de bandas, obtidos por RAPD, e o padrão de secreção de celulases dos produtos de fusão foram sempre mais semelhantes a um dos parentais. Os clones apresentaram variação quanto ao halo de hidrólise de celulose em placas de Petri e na atividade sobre papel filtro FPAases, -glicosidase ou endoglicanase, quando crescidas em cultivo submerso ou em estado sólido. Desta variabilidade, verificaram-se aumentos significativos para algumas das linhagens em relação aos parentais. A aplicação da metodologia de fusão de protoplastos para obter recombinantes entre P. echinulatum e T. harzianum, empregando a técnica do doador morto, mostrou-se adequada na geração de variabilidade para produção de celulases.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The study of cellulolytic fungi has proved to be important, considering economic interest of the cellulase complex, especially in the textile industry and, more recently, for energy purposes. In this work, the protoplast fusion was used to combine genotypes of mutants partially non repressed for cellulases production of Penicillium echinulatum (9A02S1B9) and Trichoderma harzianum (AS5CH3) using the technique dead donor, intending to obtain recombinants with higher cellulases production. In this strategy, both strains had their mycelium treated with Glucanex  0,01 g/mL, to lyse the cell wall. The protoplast obtained from the benomyl-resistant (9A02S1B9) were heat-inactivated (technique of dead donor) at 60ºC, before the step of fusion, induced by PEG4000 and Ca2+, with protoplast of the sensitive-benomyl strain (AS5CH3). Twenty four sub-clones were selected from one fusion product, after stabilization and selection strategies for precocity and efficiency in the formation clearing zones of by cellulose hydrolysis in Petri plates. The fusion products showed similar morphology and sporulation to one of parents, thirteen similar to Penicillium, nine similar to Trichoderma and two showed altered forms. The fusion products which segregate to the morphology of T. harzianum resistance to benomyl, being able to grow and sporulate in media containing up to 100 μg/mL of this inhibitor. The morphology, the profile of bands, obtained by RAPD, and the pattern of cellulase secretion by fusion products were ever more similar to one of parents. The fusants presented variation in the halo of cellulose hydrolysis in Petri plates, and in the activity on filter paper (FPAases), - glicosidase or endoglicanase, when grown submerged cultivation or solid state. From this variability, significant improvement was verified for some of the parental strains. The application of the protoplast fusion methodology to obtain recombinant between P. echinulatum and T. harzianum, using the technique of dead donor, has proved to be adequate to generate variability in the production of cellulases.
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35

Crivelente, Horta Maria Augusta 1981. "Análise do transcriptoma de Trichoderma harzianum para a bioprospecção de enzimas hidrolíticas = Analysis of Trichoderma harzianum transcriptome for bioprospecting of hydrolytic enzymes." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316510.

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Orientadores: Anete Pereira de Souza, Sindélia Freitas Azzoni
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Buscando contribuir com o desenvolvimento da tecnologia de produção do etanol de segunda geração, o presente estudo analisa o transcriptoma de T. harzianum IOC-3844 utilizando técnicas de sequenciamento high-thoughput. O principal objetivo dessas análises foi identificar, caracterizar e catalogar os transcritos expressos por T. harzianum relacionados com a degradação de substratos complexos, como o bagaço de cana de açúcar, revelando o conjunto de genes envolvidos na degradação da biomassa. A análise do transcriptoma do fungo Trichoderma harzianum sob condições que induzem a degradação da biomassa permitiu a identificação de sequências de genes potencialmente eficazes no processo de biodegradação, uma etapa essencial à compreensão do processo de hidrólise enzimática. O sequenciamento resultou em 246 milhões de sequências com 72 pb, o que corresponde a 14,7 GPB analisados. Após a montagem , 32.494 contigs foram gerados, submetidos à identificação e classificados de acordo com sua identidade. Todas as sequências de contigs foram comparados com o banco de dados do NCBI, Gene Ontology (GO terms), Enciclopédia de Genes Kyoto (KEGG), Carbohydrate Active-Enzymes (CAZYmes). Foram identificados 487 CAZymes no transcriptoma, inclusive aquelas ligadas as reações químicas de despolimerização de celulose e hemicelulose. As sequências classificadas como atividade catalítica (6.975) e atividade reguladora (143) podem estar envolvidas com esse tipo de reação.A análise permitiu definir o principal conjunto de genes envolvidos na degradação da celulose e de hemicelulose do T. harzianum , e genes acessórios relativos à despolimerização de biomassa. Uma análise dos níveis de expressão permitiu determinar os conjuntos de genes diferencialmente expressos em diferentes condições de cultivo. Os resultados obtidos acrescentam conhecimento sobre a constituição do genoma, as atividades de expressão gênica do fungo Trichoderma harzianum e fornece informações importantes a respeito dos mecanismos genéticos de degradação de biomassa que o fungo utiliza. As informações obtidas poderão ser utilizadas para outras espécies de fungos filamentosos com potencial para a biodegradação
Abstract: In order to contribute to the development of second-generation ethanol technology, this study analyzes the transcriptome of T. harzianum IOC-3844 using high-thoughput sequencing techniques. The main objective of this analysis was to identify, characterize and catalog the transcripts expressed by T. harzianum related to the degradation of complex substrates such as sugar cane bagasse, revealing the set of genes involved in the degradation of biomass. The analysis of the transcriptome of the fungus Trichoderma harzianum under conditions that induce the degradation of biomass allowed the identification of genes potentially effective in the biodegradation process, an essential step for understanding the enzymatic process. Sequencing resulted in 246 million sequences with 72 bp, which corresponds to 14.7 GBP analyzed. After assembly, 32,494 contigs were generated, identified and classified according to their identity. All sequence contigs were compared with NCBI database, Gene Ontology (GO terms), Kyoto Encyclopedia of Genes (KEGG), Carbohydrate Active-Enzymes (CAZYmes). 487 CAZymes were identified in the transcriptome, including those related to reactions of cellulose and hemicellulose depolymerization. Sequences classified as catalytic activity (6,975) and regulatory activity (143) may be involved with this type of reaction. This analysis define the set of genes involved in the degradation of cellulose and hemicellulose of T. harzianum, and accessories genes related to depolymerization of the biomass. An analysis of expression levels was used to calculate the set of differentially expressed genes in different culture conditions. The results add to knowledge about the composition of the genome and gene expression activity of the fungus Trichoderma harzianum, and provides important information regarding the genetic mechanisms of biomass degradation that the fungus uses. The information obtained may be used for other species of filamentous fungi with potential for biodegradation
Doutorado
Genetica Vegetal e Melhoramento
Doutora em Genética e Biologia Molecular
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36

Duff, Sheldon Joseph Blaine 1956. "Studies on cellulase production with pure and mixed fungal fermentations." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72840.

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37

Brito, Fabiane Silva. "Detecção e avaliação in vitro do crescimento de Trichoderma spp. isolados de composto frente à fitopatógenos." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/92688.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Agroecossistemas, Florianópolis, 2009
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A compostagem é um processo que garante o retorno da matéria orgânica e nutrientes ao solo. Estudos apontam o composto como um meio naturalmente supressivo a patógenos de plantas, o que pode estar relacionado com a presença de Trichoderma spp. no meio. Os objetivos do presente trabalho foram: comparar três métodos de isolamento de Trichoderma spp. do composto; compreender a colonização do composto com uma semana, um e dois anos de maturação comparado com o solo de áreas adjacentes ao pátio de compostagem; e verificar características úteis de Trichoderma spp. para a utilização no controle biológico de fitopatógenos. Método de iscas; diluição em série de soluções do solo e plaqueamento direto de fragmentos de composto, foram os métodos utilizados para o isolamento de Trichoderma spp. O método de plaqueamento direto foi considerado o mais viável para verificar a presença de Trichoderma spp. Esse método foi utilizado para selecionar oito isolados de Trichoderma spp.; três do composto de um ano (N1, N2 e N3), três do composto de dois anos (M1, M2 e M3), e dois do solo da mata adjacente ao pátio (S2 e S3). Os isolados M1 e M2 foram identificados, respectivamente, como Trichoderma asperellum e Hypocrea lixii. Todos os isolados foram comparados com Trichoderma asperellum de formulação comercial (TC) quanto ao crescimento micelial, esporulação em BDA (batata-dextrose-ágar) e confrontados com Sclerotinia sclerotiorum. Em seguida, apenas um dos isolados (M2) do composto de dois anos e o TC foram confrontados com S. sclerotiorum, Rhizoctonia sp. e Fusarium solani. O crescimento micelial entre isolados do composto e do solo foram semelhantes. Isolados do composto de um ano apresentaram a maior esporulação. Isolados do composto de dois anos competiram melhor frente aos patógenos, por espaço e nutrientes, um dos possíveis mecanismos para a supressividade natural do composto.
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38

Askolin, Sanna. "Characterization of the Trichoderma reesei hydrophobins HFBI and HFBII /." [Espoo, Finland] : VTT Technical Research Centre of Finland, 2006. http://www.vtt.fi/inf/pdf/publications/2006/P601.pdf.

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39

Torrie, Joan P. "Extracellular beta-D-mannanase activity from Trichoderma harzianum E58." Thesis, University of Ottawa (Canada), 1991. http://hdl.handle.net/10393/7732.

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In this work, 4 yeasts (Pichia wickerhammi, Candida wickerhammi, Pichia stipitis CBS5776, Pichia stipitis CBS5876), and 5 fungi (Theivalia spp., Thermoascus aurantiacus, Tyromyces palustris A, Aspergillus niger, Trichoderma harzianum), known to excrete enzymes capable of hydrolyzing polysaccharides found in association with $\beta$-D-mannans, were assessed for their ability to degrade $\beta$-D-mannans. The $\beta$-D-mannanase activity found in the culture filtrate of T. harzianum was selected for further study and a 'cellulase-free' $\beta$-D-mannanase isolated from culture filtrates of T. harzianum grown on medium supplemented with 1% w/v locust bean gum studied. $\beta$-D-Mannanase activity was detected in T. harzianum culture filtrates from media supplemented with 1% (w/v) Avicel, locust bean gum galactomannan, konjac root glucomannan, or spruce wood water-solubles. Medium supplemented with 1% (w/v) mannose did not induce $\beta$-D-glucomannanase or $\beta$-D-galactomannanase activity. However, when 0.5% (w/v) $\beta$-D-galactomannan was added with mannose, $\beta$-D-mannanase activity was detected in the culture filtrate. Growth of the fungus on mannan-rich locust bean gum resulted in the highest specific $\beta$-D-glucomannanase and $\beta$-D-galactomannanase values. A zymogram assay was developed to selectively detect $\beta$-D-mannanase activity in crude culture filtrates. The presence of different polysaccharides in the growth medium resulted in different $\beta$-D-mannanase zymogram profiles. Analyses of the protein profiles of the culture filtrates separated by isoelectric focusing revealed several bands having $\beta$-D-mannanase and endoglucanase activity. A protein band having $\beta$-D-mannanase activity but lacking detectable cellulase activity was identified. This enzyme was purified to homogeneity via a sequence involving ultrafiltration, ion exchange and gel filtration. This 'cellulase-free' $\beta$-D-mannanase has the highest reported pI for a fungal $\beta$-D-mannanase. The isolated enzyme had a molecular weight of 42.9 $\pm$ 4 kD, an optimum temperature of 60-65$\sp\circ$C, an optimum pH of 5.8, a pI of 6.55, and possessed at least 75% of maximum activity over a pH range from 3.21-6.8. Enzymatic activity was stable during 12 months of storage at 4$\sp\circ$C. $\beta$-D-mannanase activity was resistant to pepsin, $\alpha$-chymotrypsin, trypsin, and Staphylococcus V8 protease. The effect of metal ions, detergent and solvents on $\beta$-D-mannanase activity was also determined. Although the enzyme did not degrade Avicel or Solka floc, it did associate with both celluloses. Enzyme associated with these celluloses remained active towards locust bean gum galactomannan. The overall efficiency of the enzyme (V$\sb{\rm max}$/K$\sb{\rm m})$ for the target substrate, locust bean gum galactomannan, was reduced by the presence of 1.0% w/v Avicel. Of the four $\beta$-D-mannans tested, the enzyme had greatest overall efficiency towards konjac glucomannan. However, deacetylation of konjac glucomannan lowered the efficiency of the enzyme by 41.5%. (Abstract shortened by UMI.)
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40

Punshon, Christine Angela. "Survival of Trichoderma harzianum, biotype Th4, after heat treatments." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0017/MQ55704.pdf.

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41

Wallace, R. J. "Fungicide resistance of Trichoderma spp. colonising freshly-felled timber." Thesis, University of Portsmouth, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316411.

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42

Adams, Paul. "Potential Use of Trichoderma harzianum (T22) in land remediation." Thesis, University of Surrey, 2006. http://epubs.surrey.ac.uk/741/.

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43

Belshaw, N. J. "The nuclear matrix and gene expression in Trichoderma reesei." Thesis, University of East Anglia, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296346.

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44

GARCIA, NUÑEZ HILDA GUADALUPE 266328, Nuñez Hilda Guadalupe García, and Campos Angel Roberto Martínez. "Evaluación de los mecanismos de acción biológica de Trichoderma." Tesis de doctorado, Universidad Autónoma del Estado de México, 2016. http://hdl.handle.net/20.500.11799/66029.

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Este trabajo describe los mecanismos de control biológico que se expresan en Trichoderma, además mediante la aplicación de los marcadores ITS y Tef1α se realiza la caracterización taxonómica de 10 cepas de Trichoderma aisladas en la región hortícola de Tenango y a través de pruebas de confrontación dual se determina su capacidad antagónica contra diferentes patógenos fúngicos de la papa
El presente trabajo demostró que en la Peñuela localidad del Municipio de Zinacantepec, Estado de México, en los últimos años, el cultivo de la papa (Solanum tuberosum) se ha visto afectado por la presencia de agentes patógenos principalmente hongos como P. infestans, F. avenaceum, Alternaria sp y Rhizoctonia sp. causantes de enfermedades que degradan la calidad del tubérculo tales como Tizón temprano, Damping off, Tizón tardío y Rizoctoniasis respectivamente. La caracterización morfológica ayudó a ubicar taxonómicamente a nivel de género a los cuatro hongos patógenos. Pero, para el caso de Fusarium fue necesaria la caracterización molecular lo cual permitió comprobar que F. avenaceum es una especie patógena para el cultivo de papa en esta zona de estudio. Ya que esta especie es reportada como patógena de cultivos de gramíneas como la avena, sin embargo, se encontró que rompió las barreras agroecológicas y ahora daña a este tubérculo. También con herramientas moleculares utilizando los marcadores ITS y Tef1α se ubicaron taxonómicamente a diez cepas nativas de Trichoderma; 6 cepas como T. asperellum (TL2, TL4, TX7, TX8, TT6,TF8) y 4 cepas como Hipocrea lixii (TL5,TL6,TF10 TJ6), el teleomorfo de T. harzianum. Como estrategia ecológica y con la finalidad de conocer el potencial de biocontrol de estas cepas de Trichoderma se realizaron pruebas de antagonismo mediante cultivos duales enfrentando a los patógenos que afectan el cultivo de papa Alternaria sp., Rhizoctonia sp. P. infestans y Fusarium avenaceum. Los resultados registraron diferencias significativas en el porcentaje de biocontrol de las cepas de Trichoderma sobre los patógenos. Donde la cepa TX8 (T. asperellum) registró los porcentajes más altos de inhibición sobre, F. avenaceum, Alternaria sp y P. infestas con 100%, 100% y 98.12%, respectivamente Para el caso de Rhizoctonia sp., H. lixii presentó los porcentajes de inhibición más altos 65% y 51% para las cepas TF10 y TL5 respectivamente. La cepa TL4 (T. asperellum) hacia los cuatro patógenos mostró el valor más bajo de antagonismo. La respuesta antagónica de la cepas nativas de Trichoderma desencadeno mecanismos de acción biológica, donde el más frecuente fue la competencia hacia Alternaria sp. y Rhizoctonia sp. y P. infestans mientras que para F. avenaceum la antibiosis fue el mecanismo que favoreció el antagonismo. Sin embargo, también el micoparasitismo en algunos casos se presentó junto con la competencia hacia P. infestans y Rhizoctonia sp.
CONACyT UAEMEX COMECyT
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45

Gómez, Mendoza Diana Paola. "Proteômica aplicada à caracterização do secretoma de Trichoderma harzianum." reponame:Repositório Institucional da UnB, 2013. http://repositorio.unb.br/handle/10482/13439.

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Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia Molecular, 2013.
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Trichoderma harzianum é um fungo filamentoso capaz de secretar enzimas hidrolíticas ao meio extracelular as quais agem despolimerizando componentes da biomassa vegetal como celulose e hemicelulose. O conjunto de proteínas secretadas por uma célula é denominado de secretoma, uma subpopulação do proteoma total. Amostras correspondentes ao secretoma de T. harzianum foram obtidas por fermentação submersa (SmF) em meio sintético suplementado com 1 %(m/v) de glicose, celulose, xilana ou bagaço de cana como fonte de carbono. Os secretomas foram posteriormente submetidos à análise proteômica seguindo duas abordagens distintas, eletroforese bidimensional (2-DE) seguida de espectrometria de massas MALDI-TOF/TOF para a identificação de polimorfismos proteicos provenientes do gel, e LC-MS/MS para identificação do total de proteínas presentes em cada amostra. Os secretomas de T. harzianum foram igualmente tratados com a enzima PNGase F a fim de detectar presença de proteínas glicosiladas e mudanças no perfil bidimensional das amostras. O crescimento nas diferentes fontes de carbono resultou na identificação de diversos grupos de proteínas extracelulares que incluíram glicosil hidrolases como celulases, xilanases, pectinases e quitinases, bem como proteínas associadas à parede celular fúngica como hidrofobinas e proteínas elicitoras e um alto número de proteínas putativas, cuja expressão diferencial parece estar regulada pela natureza e complexidade da fonte de carbono utilizada na cultura. Adicionalmente este trabalho apresenta evidência sobre a ocorrência de complexos multienzimáticos no secretoma do fungo após o crescimento por SmF em bagaço de cana, graças à utilização de técnicas eletroforéticas, enzimológicas e espectrométricas como BN-PAGE, zimografia e LC-MS/MS, respectivamente. Os resultados indicam que proteínas secretadas por T. harzianum naturalmente envolvidas na desconstrução de substratos (hemi) celulolíticos e quitinolíticos formam parte de elementos oligoméricos constituídos por subunidades de diferente especificidade catalítica que aparentemente são requeridas para uma conversão eficiente e específica dos polímeros da biomassa. _______________________________________________________________________________________ ABSTRACT
Trichoderma harzianum is a filamentous fungus able to secret hydrolytic enzymes to the extracellular medium which act degrading the biopolymeric components of plant biomass such as cellulose and hemicellulose in fermentable sugars. This set of secreted proteins corresponds to the secretome, a subset of the proteome. The samples related to the T. harzianum secretome were obtained by submerged fermentation (SmF) in synthetic medium supplemented with1% (w/v) glucose, cellulose, xylan or sugarcane bagasse as a carbon source. The secretomes were explored by two different proteomic approaches, gel-based proteomics using two-dimensional electrophoresis (2-DE) followed by MALDI-TOF/TOF mass spectrometry for the identification of the protein polymorphisms from the gel, and gel-free proteomics using LC-MS/MS for identification of the total of protein present in each sample. The T. harzianum secretomes were also treated with the enzyme PNGase F in order to detect the presence of glycosylated proteins and changes in the dimensional profile of the samples. Growth on different carbon sources resulted in the identification of several groups of extracellular proteins such as glycoside hydrolases including cellulases, xylanases, pectinases, chitinases, as well as cell-wall associated hydrophobins and elicting proteins, and putative proteins whose differential expression appears to be regulated by the nature and complexity of the carbon sources used in the culture. In addition the occurrence of multienzymatic complexes in the secretome after SmF growth in sugarcane bagasse containing medium was demonstrated by means of electrophoretic, spectrometric and enzymologic techniques, such as BN-PAGE, zimography, and LC-MS/MS, respectively. The results indicate that enzymes and proteins secreted by T. harzianum naturally involved in the deconstruction of (hemi) cellulolytic and chitinolytic substrates are part of oligomeric elements composed of subunits with different catalytic specificities apparently required for specific and efficient conversion of biomass polymers.
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46

Steindorff, Andrei Stecca. "Genômica estrutural e funcional de fungos do gênero Trichoderma." reponame:Repositório Institucional da UnB, 2016. http://repositorio.unb.br/handle/10482/20049.

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Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia Molecular, 2016.
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O controle biológico é um processo complexo que inclui diferentes mecanismos e uma diversidade de vias metabólicas. Espécies de Trichoderma harzianum são conhecidas por sua atividade de biocontrole contra patógenos de plantas. Para melhor entender os mecanismos utilizados por T. harzianum no controle biológico, no presente trabalho foi sequenciado o genoma do isolado TR274 usando sequenciamento Illumina, assim como seu respectivo transcritoma na interação direta com Scletotinia sclerotiorum ou na presença de sua parede celular. A montagem do genoma feita utilizando o programa AllPaths-LG cobertura máxima de 100x, resultou em 2282 contigs, tamanho do genoma de 40,8 Mb e um conteúdo GC de 47.7%, similar aos outros genomas de Trichoderma. Um total de 13932 genes foram anotados. Análise do Core Eukariotic Genes Dataset (CEGMA) sugere que o genoma está 100% completo e 97,9% das sequencias de RNA-seq alinharam corretamente no genoma. A análise filogenética usando proteínas ortólogas com todas as espécies de Trichoderma sequenciadas no JGI, confirmam a divisão nas seções Tricoderma (T. asperellum e T. atroviride), Longibrachiatum (T. reesei, T. citrinoviride e T. longibrachiatum) e Pachibasium (T. harzianum e T. virens). Das proteínas ortólogas anotadas, 8242 compõem proteínas compartilhadas por todas as espécies, as proteínas espécie específicas variam de 262 (T. reesei) a 1803 (T. longibrachiatum). Os dois genomas de T. harzianum analisados sugerem uma alta similaridade entre eles, mesmo tendo sido isolados de locais e continentes distintos, um de solo de cerrado no Brasil e outro de solo de jardim na Inglaterra. Análises de genes envolvidos com o metabolismo secundário, CAZymes, transportadores, proteases e fatores de transcrição foram feitas. A seção Pachibasium expandiu virtualmente todas as categorias analisadas quando comparada com as outras seções. Análise CAFE mostrou uma correlação positiva entre estas expansões e o tamanho dos genomas. O subgrupo C1 das quitinases foi completamente perdido pela seção Longibrachiatum. Estes resultados sugerem que estas famílias proteicas tem um importante papel nos seus respectivos fenótipos. As abordagens transcritômicas mostraram que a interação entre T. harzianum e S. sclerotiorum é bem complexa e envolve a produção de metabólitos secundários e síntese de transportadores antes e durante o contato, com uma modulação principalmente de enzimas hidrolíticas após o contato. Dos genes encontrados diferencialmente expressos na condição de crescimento em parede celular, 86,8% foram também encontrados diferencialmente expressos na interação direta. Cerca de 25% de todo o genoma de T. harzianum foi modulado durante a interação com S. sclerotiorum. _________________________________________________________________________________________________ ABSTRACT
Biological control is a complex process, which requires many mechanisms and a high diversity of biochemical pathways. Trichoderma harzianum species complex are well known for their biocontrol activity against many plant pathogens. To gain new insights into the biocontrol mechanism employed by T. harzianum, we sequenced genome of the isolate TR274 with its transcriptome during direct interaction with the fungal pathogen Sclerotinia sclerotiorum and its cell wall, using Illumina sequencing. Whole genome assembly was performed using AllPaths-LG, with a maximum coverage of 100x. The assembly resulted in 2282 contigs, with an estimated genome size of 40.8 Mb and GC content of 47.7%, similar to other Trichoderma genomes. Using the JGI Annotation Pipeline we predicted 13,932 genes, with high transcriptome support. Core Eukariotic Genes Dataset (CEGMA) tests suggested 100% genome completeness and 97.9% of RNA-SEQ reads mapped to the genome. The phylogenetic comparison using orthologous proteins with all Trichoderma genomes sequenced at JGI, corroborates the Trichoderma section division described previously (T. asperellum and T. atroviride), Longibrachiatum (T. reesei, T. citrinoviride and T. longibrachiatum) and Pachibasium (T. harzianum and T. virens). A Venn diagram was built with orthologs proteins, with 8242 composing the core protein group and species specific varying from 262 proteins (T. reesei) to 1803 (T. longibrachiatum). The comparison between two Trichoderma harzianum CBS 226.95 and TR274 isolates, suggests a high genome similarity. Analyses of the secondary metabolites, CAZymes, transporters, proteases and transcription factors were performed. The Pachybasium section expanded virtually all categories analyzed compared with the other sections. CAFE analysis showed positive correlation between these families and genome size. The chitinase subgroup C1 was completely absent in Longibrachiatum section members. These results suggest that these proteins families play an important role on their respective phenotypes. Transcriptome analysis suggests that the interaction between T. harzianum and S. sclerotiorum is complex, involving production of secondary metabolites and transporters before and during the contact, with a modulation of CAZymes after contact. A total of 86.8% of differentially expressed genes during growth on Sclerotinia sclerotiorum cell wall were found during direct interaction. Approximately the 25% of whole T. harzianum genome was seen to be modulated during the interaction with S. sclerotiorum.
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47

Araujo, Alyson Silva de. "Biochar e Trichoderma harzianum no controle de Macrophomina phaseolina." reponame:Repositório Institucional da UnB, 2018. http://repositorio.unb.br/handle/10482/32072.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, Programa de Pós-Graduação em Agronomia, 2018.
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Macrophomina phaseolina é um importante patógeno habitante do solo, associado ao “damping- off” e podridões de raízes e caules em mais de 700 espécies de plantas. O uso de biochar (BCH) de lodo de esgoto, aplicado ao solo, tem despertado interesse em diferentes estudos para o controle de doenças em plantas, proporcionando uma inibição ou mesmo suprimindo fitopatógenos. O controle biológico é evidenciado por ser uma alternativa eficaz para o manejo de diferentes fitopatógenos. Trichoderma é um dos mais estudados e utilizados agentes de biocontrole de doenças vegetais em todo o mundo. O objetivo desse trabalho foi avaliar os efeitos da aplicação ao solo de BCH, Trichoderma harzianum e da associação BCH + T. harzianum sobre M. phaseolina em aspectos agronômicos das culturas de soja, milho, feijão e algodão inoculadas ou não com o fitopatógeno. Foi avaliado o efeito direto de concentrações (0,0; 0,5; 1,0; 2,0; 5,0 e 10,0%) de BCH sobre o crescimento micelial de isolados de M. phaseolina. Foi observado ainda a capacidade de biocontrole por meio do uso do pareamento de cultura (T. harzianum x M. phaseolina) com ou sem biochar. Além disso, foi avaliado o uso de BCH, do T. harzianum, e da associação BCH + T. harzianum em plantas de feijão e soja para controle de M. phaseolina em experimento conduzido em casa de vegetação. Biochar de lodo de esgoto, pirolisado a 500 oC e utilizado em baixa concentração (0,5%), possui efeito direto no controle in vitro de diferentes isolados de M. phaseolina. No entanto, concentrações mais elevadas do BCH estimulou o crescimento do fungo. Trichoderma harzianum (linhagem 1306) inibiu o crescimento micelial de M. phaseolina, em meio de cultura com ou sem biochar. Macrophomina phaseolina afeta negativamente: (a) a germinação e sobrevivência de plantas de soja e; (b) a germinação, sobrevivência e número de vagens de plantas de feijão comum. O isolado 428 de M. phaseolina reduziu todos os índices agronômicos (germinação, sobrevivência, número de vagens, massa fresca e seca) de plantas de feijão. O uso de BCH aumentou o número de vagens em plantas de soja, inoculadas ou não com M. phaseolina. A associação T. harzianum + BCH de lodo de esgoto aumentou o número de vagens, massa fresca e seca de plantas de feijão, inoculadas ou não com M. phaseolina.
Macrophomina phaseolina is an important soil pathogen, associated with “damping-off” and root and stem rot in more than 700 plant species. The use of biochar (BCH) of sewage sludge applied to the soil, has aroused interest in studies for the control of diseases in plants, providing an inhibition of plant pathogens. Biological control is evidenced as an effective alternative for the management of different phytopathogens. Trichoderma is one of the most studied and used biocontrol agents of plant diseases worldwide. The objective of this work was to evaluate the effects of BCH, Trichoderma harzianum and BCH + T. harzianum on M. phaseolina and on agronomic aspects of soybeans, maize, beans and cotton inoculated or not with M. phaseolina. The direct effect of concentrations (0.0, 0.5, 1.0, 2.0, 5.0 and 10.0%) of BCH on the mycelial growth of M. phaseolina isolates was evaluated. It was also observed the biocontrol capacity using culture pairing (T. harzianum x M. phaseolina) with or without biochar. In addition, the use of BCH, T. harzianum, and the association BCH + T. harzianum in bean and soybean plants were evaluated for M. phaseolina control in a greenhouse experiment. Biochar of sewage sludge, pyrolyzed at 500 oC and used in low concentration (0.5%), has direct effect on the in vitro control of isolates of M. phaseolina. However, higher concentrations of BCH stimulated fungal growth. Trichoderma harzianum (strain 1306) inhibited the mycelial growth of M. phaseolina, in culture medium with or without biochar. Macrophomina phaseolina negatively affects: (a) the germination and survival of soybean plants, and; (b) the germination, survival and number of pods of common bean plants. Isolate 428 from M. phaseolina reduced all agronomic characteristics (germination, survival, number of pods, fresh and dry mass) of bean plants. The use of BCH increased the number of pods in soybean plants, inoculated or not with M. phaseolina. The association of T. harzianum + BCH of sewage sludge increased the number of pods, fresh and dry mass of bean plants, whether or not inoculated with M. phaseolina.
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48

Almança, Marcus André Kurtz. "Aspectos da interação arroz-Trichoderma spp. em solos alagados." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/28047.

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Espécies de Trichoderma são bastante estudadas atualmente para o controle biológico de fitopatógenos habitantes do solo e para a promoção de crescimento de plantas. Entretanto, cada vez mais se busca conhecer o comportamento deste antagonista em diferentes ambientes e os possíveis mecanismos envolvidos na sua interação com as plantas e os fitopatógenos. O objetivo deste trabalho foi avaliar o comportamento de isolados de Trichoderma spp. em ambiente alagado, cultivado com diferentes cultivares de arroz e os possíveis mecanismos que podem estar envolvidos nesta interação. Em todo o trabalho foram utilizados seis isolados de Trichoderma spp. e sete cultivares de arroz. Foram analisadas a sobrevivência em solo sob inundação, emergência, massa seca e altura de plantas de diferentes cultivares de arroz, além da produção de protease, AIA e sideróforos. Verificou-se que os isolados de Trichoderma spp. testados sobreviveram em solo sob inundação e ainda aumentaram a sua população nestas condições. Os isolados THAR e TSP2 proporcionaram efeito negativo na emergência das plantas das cultivares 416 e 418. Quanto à altura somente o isolado TSP2 foi superior a testemunha na cultivar 421. Entretanto, houve diferença significativa entre os isolados nas cultivares 418 e 420. Na variável peso seco houve diferença entre os isolados, mas nenhum foi superior a testemunha na cultivar 416. Na comparação das cultivares quando tratadas com o mesmo isolado, observou-se que na emergência de plantas, houve diferença na testemunha e no isolado TSP2. Para altura de plantas houve diferença das cultivares dentro dos tratamentos e também na testemunha. Para peso seco somente houve diferença na testemunha. Todos os isolados produziram sideróforos, com a mesma intensidade de cor. Quanto à produção de AIA, três dos cinco isolados testados produziram este composto, com destaque para o isolado TARV. Todos os isolados testados produziram proteases, porém houve diferença entre isolados no diâmetro da colônia. Conclui-se que Trichoderma spp. é capaz de sobreviver em solo sob inundação e também apresenta um comportamento diferenciado com cultivares de arroz. Além disto, os isolados testados produzem compostos que podem estar envolvidos nos mecanismos de controle de fitopatógenos e promoção de crescimento de plantas de arroz.
Trichoderma spp. are extensively studied for the biological control of soil borne plant pathogens and to promote growth of plants. However, it is necessary to keep studying the behavior of the antagonist in different environments and the possible mechanisms involved in its interaction with plants and plant pathogens. The purpose of this study was to evaluate the survival ability of isolates of Trichoderma spp. in an flooded environment with different rice varieties and the possible mechanisms that acting in this interaction. Six Trichoderma spp. isolates and seven rice cultivars were used in this experiments. The survival in paddy soil, plant emergency, dry weight and height of different rice cultivars of rice in addition to the production of protease, IIA and siderophores by the strains were evaluated. We observed that the isolates of Trichoderma spp. tested survived in paddy soil and also increased the population in these conditions. The isolates THAR and TSP2 caused negative effect on the emergence of the plants of cultivars 416 and 418. As for the height alone the isolate TSP2 was higher than control in cultivar 421. However, there was a significant difference between the isolates in the cultivars 418 and 420. In variable dry weight there was difference only between isolates, but none was higher than the control in cultivar 416. In the comparison of cultivars when treated with the same isolate, it was observed that in emergence of plants there was a difference in the control and in isolate TSP2. For height of plants there was a difference of cultivars within the treatments and also in control. For dry weight only difference was alone in control. All isolates produced siderophores, with the same intensity of color. As for the production of IIA, three of the five isolates tested produced this compound, with an emphasis on the isolate TARV. All isolates produced proteases, but there was difference between isolates in colony diameter. So it appears that Trichoderma spp. is able to survive in paddy soil and also presents a different behavior with cultivars of rice. In addition, it isolates the producing compounds that may be involved in the mechanisms of control of plant pathogens and promote growth of rice plants.
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49

Chan, Ho Tong Laetitia. "Amélioration du champignon cellulolytique Trichoderma reesei par reproduction sexuée." Thesis, Paris, Institut agronomique, vétérinaire et forestier de France, 2017. http://www.theses.fr/2017IAVF0017.

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Abstract:
Dans le cadre de la production de bioéthanol de deuxième génération, l’ingénierie génétique de Trichoderma reesei est une des solutions envisagées pour diminuer le coût de l’étape d’hydrolyse enzymatique. Elle permet d’améliorer les performances de sécrétion de ce champignon filamenteux producteur de cellulases et les propriétés de ces enzymes. Comme de nombreux champignons industriels, T. reesei a longtemps été considéré comme possédant exclusivement un cycle asexuel. La mise en évidence récente d’un cycle de reproduction sexuée chez ce champignon filamenteux ouvre de nouvelles perspectives d’amélioration des souches utilisées en biotechnologie. Cependant, comme toutes les souches industrielles de T. reesei dérivent de l’isolat sauvage QM6a, elles sont toutes de type sexuel MAT1-2 et stériles en tant que femelles. L’objectif de ce travail de thèse est de mettre en place la reproduction sexuée comme outil génétique et d’amélioration des performances des souches industrielles. Son utilisation en complément des outils d’ingénierie génétique permet de combiner des caractères intéressants ou d’en générer de nouveaux, de stabiliser les souches industrielles en éliminant les mutations non désirées, de s’affranchir des marqueurs de sélection et d’identifier les gènes et mutations responsables d’un caractère d’intérêt. La première partie de ce travail a été consacré à l’optimisation de la reproduction sexuée puis à l’étude des étapes et des mécanismes de la reproduction sexuée entre souches sauvages et hyperproductrices. Dans un deuxième temps, nous avons mis en place la reproduction sexuée entre des souches hyperproductrices femelles stériles, à l’aide de la stratégie originale de la « souche assistante », qui a abouti au rétablissement partiel de leur reproduction sexuée. Afin de compléter ce rétablissement, une étude de l’étape de fécondation que nous supposons être l’étape problématique dans notre stratégie a été initiée. Parallèlement, l’exploitation de la reproduction sexuée entre souches sauvage et hyperproductrices a permis de générer une souche hyperproductrice de cellulases, de type sexuel MAT1-1 donc compatible avec toutes les souches industrielles, femelle fertile et possédant une activité β-glucosidase améliorée. Enfin, la reproduction sexuée associée à la génétique classique (« Bulk Segregant Analysis ») et aux techniques de séquençage haut débit a été mise en oeuvre pour permettre l’identification de mutations impliquées dans des phénotypes d’intérêt
Genetic engineering of Trichoderma reesei is one of the solutions considered to reduce the cost of the enzymatic hydrolysis step in second-generation ethanol production processes. It allows the improvement of the secretory performances of this cellulase producer fungus and the properties of its enzymes. Like many industrial fungi, T. reesei has long been considered to possess exclusively an asexual cycle. The recent discovery of a sexual reproduction cycle in this filamentous fungus opens up new prospects of improvement for strains used in biotechnology. However, all industrial strains of T. reesei are derived from the wild isolate QM6a and therefore possess the MAT1-2 mating type and are female sterile.The aim of this work was to develop sexual reproduction as a genetic tool and to improve the performance of the industrial strains. In combination with the genetic engineering tools, it would enable combination of interesting traits or generation of new ones, improve strains stability by purging deleterious mutations, selection markers elimination and identification of genes and mutations responsible of interesting characteristics.The first part of this work was dedicated to the optimization of sexual reproduction and to the study of the steps and mechanisms of sexual reproduction between wild-type and hyperproducer strains. In a second step, we set up sexual reproduction between female sterile hyperproducer strains, using the original "assistant strain" strategy, which resulted in the partial restoration of their sexual reproduction. A study of the fertilization step was also initiated, as we suspect it to be the blocking point in our strategy. In a second part, we took advantage of sexual reproduction between wild-type and hyperproducer strains for (i) the generation of a MAT1-1 mating-type strain compatible with all industrial strains, female fertile and possessing improved β-glucosidase activity and (ii) the implementation of a bulk segregation analysis associated with high-throughput sequencing techniques to identify mutations involved in phenotypes of interest
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50

Lo, Chi-Ming. "Cellulase Production by Trichoderma Reesei Rut-C30." University of Akron / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=akron1205776927.

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