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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Fungal endophytes, grasses and competition : an experimental and field approach /

Rakocevic, Tomo. January 2005 (has links)
Thesis (M.Sc.)--York University, 2005. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 79-101). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url%5Fver=Z39.88-2004&res%5Fdat=xri:pqdiss &rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR11880
22

Produção de celulases por fungos endofíticos e aplicação das enzimas na sacarificação do bagaço de cana-de-açúcar /

Marques, Natália Paganini. January 2017 (has links)
Orientador: Daniela Alonso Bocchini / Banca: Luis Henrique Souza Guimarães / Banca: Kelly Johana Dussan Medina / Banca: Jonas Contiero / Banca: Eleni Gomes / Resumo: Atualmente, há um crescente interesse na produção de bioetanol celulósico como biocombustível de segunda geração, sendo uma alternativa promissora aos combustíveis fósseis. Fungos tem sido constantemente isolados na busca por novas fontes de celulases e os endofíticos são interessantes para esta finalidade, por serem potenciais produtores de enzimas de degradação de material vegetal, incluindo celulases, e pouco estudados neste sendido. O presente estudo teve por finalidade a avaliação da influência das condições de cultivo (isolado e co-cultivo) para a produção de celulases pelos fungos endofíticos Botryosphaeria sp. AM01 e Saccharicola sp. EJC04, por meio de metodologias estatísticas, além da utilização dos extratos enzimáticos na sacarificação do bagaço de cana-de-açúcar pré-tratado hidrotérmicamente com NaOH, otimizando-se também esta etapa empregando-se as ferramentas estatísticas citadas. Para a condição de co-cultivo dos fungos, a quantidade de substrato (5,7g) e a umidade inicial do substrato (60,6%) foram otimizadas visando maximizar a produção de endoglunacase (121,56 U/g). Para o cultivo isolado de Botryosphaeria sp. AM01, foi possível a produção de endoglunacase (168,99 U/g), empregando a concentração de NaNO3 a 6,0 g/L e 5,0 g como quantidade de substrato. Para o cultivo isolado de Saccharicola sp. EJC04, obteve-se a condição ótima para produção de β-glicosidase (750,37 U/g) na concentração de ureia de 0,0836 g/L, teor de umidade de 49,2% e quantidade de substrat... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: There is a great interest in the production of cellulosic bioethanol as second generation biofuel and it is a promising alternative to fossil fuels. Fungi have been constantly isolated in the search for new sources of cellulases and the endophytics interesting for this purpose, being potential producers of plant material degrading enzymes, including cellulases, and underexploited in this sense.The present study had as purpose the optimization of culture conditions (monoculture and co-cultivation) for the production of cellulases by the endophytic fungi Botryosphaeria sp. AM01 and Saccharicola sp. EJC04, by statistics methodology, and also the use of enzymatic extracts in saccharification of sugarcane bagasse submitted to hydrothermal pretreatment with NaOH, optimizing this step using those statistical tools. For the fungi co-cultivation, the amount of substrate (5.7g) and the substrate initial moisture (60.6%) were optimized to maximize the production of endoglunacase (121.56 U/g). For the monoculture of Botryosphaeria sp. AM01, it was possible to produce endoglunacase (168.99 U/g), using the concentration of NaNO3 at 6.0 g/L and 5.0 g as substrate amount. For the monoculture of Saccharicola sp. EJC04, the optimal condition for β- glycosidase production (750.37 U/g) was obtained using urea at 0.0836 g/L, initial substrate moisture at 49.2% and substrate amount of 3.84 g. The enzymatic extracts obtained under optimized conditions were used in the saccharification of sugarcane bagasse submitted to alkaline hydrothermal pretreatment with NaOH. The pre-treated bagasse characterization indicated 59.52, 31.62 and 11.32% as the contents of cellulose, hemicellulose and lignin, respectively. The saccharification performed with the enzymatic extract produced by Botryosphaeria sp. AM01 was more efficient in glucose (Full abstract, click on electronic access below) / Doutor
23

Symbiosis in the Context of an Invasive, Non-Native Grass: Fungal Biodiversity and Student Engagement

Lehr, Gavin Charles, Lehr, Gavin Charles January 2018 (has links)
Grasslands in the western United States face severe environmental threats including those brought about by climate change, such as changes in precipitation regimes and altered fire cycles; land-use conversion and development; and the introduction, establishment, and spread of non-native species. Lehmann’s lovegrass (Eragrostis lehmanniana) was introduced to the southwestern United States in the early 1900s. Since its introduction, it has become the dominant grass in the mid-elevation grasslands of southern Arizona, including the Santa Rita Experimental Range (SRER), where it has displaced native grasses including Arizona cottontop, three awns, and gramas. Like all plants in terrestrial ecosystems, this grass harbors fungal symbionts that can be important for its establishment and persistence. This thesis focuses on fungal symbionts of Lehmann’s lovegrass and has two components. First, the diversity and distributions of endophytes in Lehmann’s lovegrass are evaluated in the context of biotic and abiotic factors in the SRER. Culturing from roots and shoots of Lehmann’s lovegrass at points beneath and outside the canopy of native mesquites, which are encroaching on grasslands over time, provides insight into how a single plant species can exhibit local variation in the composition of its symbionts. Second, the thesis is used as the basis for engagement of students in science, technology, engineering, and mathematics (STEM) through the development and implementation of classroom- and field activities centered on endophytes, which help high school students address core learning aims while also gaining real research experience. Engaging students in important questions relevant to their local environment can catalyze interest in science and help students cross the threshold into research. The contributions of such approaches with respect to learning not only fulfills key next-generation science standards and common core objectives, but provides students with a meaningful introduction to the excitement, importance, and accessibility of science.
24

Traditional Chinese medicinal plants and their endophytic fungi: isolation, identification, and bioassay

Huang, Wuyang., 黃午陽. January 2008 (has links)
published_or_final_version / Biological Sciences / Doctoral / Doctor of Philosophy
25

Host-, Geographic-, and Ecological Specificity of Endophytic and Endolichenic Fungal Communities

U'Ren, Jana M. January 2011 (has links)
As one of the most diverse and ecologically important clades of life, fungi are best known as pathogens, saprotrophs, mycorrhizae, and lichens. Yet an enormous amount of previously unknown diversity occurs among endophytic and endolichenic fungi--species-rich, horizontally transmitted fungi that live within asymptomatic photosynthetic structures such as leaves and lichens. Here, I explore the biodiversity of these understudied symbiotrophs and the ecological and biogeographic factors influencing their communities.To evaluate methods currently used in ecological studies of environmental samples of fungi, I assessed inter- and intraspecific divergence of a fast-evolving locus for four genera commonly found as endophytes, and compared analytical methods for identifying and delimiting OTUs. Then I used the most robust methods to show that after soil contact, seeds of a focal tree species contain diverse fungi that are closely related to endophytes and pathogens.To explore the ecological specificity of symbiotrophic fungi, I examined endophytic, endolichenic, and saprotrophic communities inhabiting physically proximate hosts in a biotically rich area of southeastern Arizona. I found that endolichenic fungi are largely distinct from plant-associated fungi, with the exception of a group of ecologically flexible symbionts that occur in lichens and mosses. Although numerous endophytes were found in non-living leaves, fungi that were highly abundant in leaf litter were seldom found as endophytes.To assess symbiotroph biodiversity and ecological specificity at a broad geographic and phylogenetic scale, I isolated>4100 endophytic and endolichenic fungi from diverse communities of plants and lichens across five climatic regions in North America. I found that the abundance, diversity, and composition of these nearly ubiquitous fungi differ as a function of climate, locality, and host. Differences among communities reflect environmental characteristics more strongly than geographic distance.Last, I addressed a series of hypotheses regarding the ecological specificity of fungi inhabiting living and non-living leaves. I show that like endophytes, saprotrophic communities are structured by environmental characteristics, and at small spatial scales by host and leaf status. Yet, differences in communities between living leaves and leaf litter suggest that most endophytes either rapidly complete their life-cycle or are out-competed by robust saprotrophs once leaves senesce.
26

Estudo químico e biológico dos fungos endofíticos Microascus sp. e Nodulisporium sp. assosciados à alga vermelha Asparagopsis Taxiformis /

Santos, Camila Souza. January 2016 (has links)
Orientador: Dulce Helena Siqueira Silva / Banca: Ian Castro-Gamboa / Banca: Geraldo Humberto Silva / Resumo: O presente trabalho apresenta os resultados obtidos sobre o estudo químico e biológico dos fungos endolíticos N odulisporium sp . e M icroascus sp . associados à alga vermelha Asparagopsis taxiformis . Para tanto, fez - se uso das técnicas cromat ográficas de sepa ração CLAE (cromatografia líquida de alta eficiência), CG - EM (cromatografia gasosa acoplada a espectrometria de massas) e cromatografia em coluna (CC), além da avaliação dos potenciais antifúngico, anticolinesterásico e citotóxico dos extratos brutos, fraç ões e subfrações de N odulisporium sp . e M icroascus sp. O estudo químico levou ao isolamento de quatro substâncias pertencentes à classe das diidroisocumarinas (substâncias S 1, S 2, S 10 e S 11 ), duas dicetopiperazinas (substâncias S 3 e S 4 ), um composto fenólico ( S 12 ), uma isoflavona ( S 8 ), um derivado hidroxiimino ( S 9 ), uma mistura contendo uma amida ( S 5 ) e um diol vicinal ( S 6 ), além do isolamento de um composto aromático (substância S 7 ), ainda em fase de identificação. As estruturas das substâncias isoladas foram identificadas com base nos dados espectroscópicos de ressonância magnética nuclear uni e bidimensional (RMN de 1 H, RMN de 13 C, TOCSY - 1D, HSQC, HMBC, COSY e HSQC - TOCSY), UV - Vis e espectrometria de massas (EM). C omporta ressaltar que o diol vicinal ( S 6 ) está sendo descrito pela primeira vez na literatura e que as demais substâncias isoladas não haviam sido relatadas para os gêneros Nodulisporium ou Microascus . A avaliação das atividades antifúngica e anticolineste rásica evidenciaram o potencial de bioatividade de extratos e frações de N odulisporium sp . e M icroascus sp, sendo reveladas atividades forte e moderada frente à s enzimas acetilcolinesterase humana e de enguia elétrica. Este é o primeiro estudo químico e biológico relatado na literatura para os endófitos Nodulisporium sp . e Microascus... / Abstract: This work present s results from the chemical and biological study of endophytic fungal strains of Nodulisporium sp and Microascus sp associated to the red alga Asparagopsis taxiformis . Chromatographic separation techniques as HPLC, GC - MS and CC have been used in addition to bioassays for evaluation of the antifungal, anticholinesterasic and cytotoxic potential of crude extracts, fractions and subfractions of Nodulisporium sp and Microascus sp fungal strains. The c hemical study led to the isolation of four dihydroisocoumarins (compounds S1, S2, S10 and S11 ), two diketopiperazines (compounds S3 and S4 ), one phenolic compound ( S1 2 ), one isoflavone ( S8 ), o ne hydroxyl - imino derivative ( S9 ), a mixture containing one amide ( S5 ) and one novel vicinal diol ( S6 ), in addition to one aromatic compound (compounds S7 ) still under structural investigation. Their structures were identified based on 1D and 2D NMR spectroscopic data ( 1 H and 13 C NMR, TOCSY - 1D, HSQC, HM BC, COSY and HSQC - TOCSY), UV - Vis and mass spectrometry (MS) . Compound S 6 is an aliphatic vicinal diol and is herein described as a novel compound whereas the remaining compounds had not been described before neither for Nodulisporium nor Microascus genera. Antifungal and anticholinesterase activities evaluation of extracts and fractions of Nodulisporium sp e Microascus sp evidenced their strong and moderate potential against human and electric eel acetylcholinesterase enzymes. This is the first report on th e chemical and biological studies of endophytic fungi Nodulisporium sp and Microascus sp, associated to the red algae Asparagopsis taxiformis. Their promising results highlight the outstanding chemodiversity of extracts and fractions from such fungal strai ns from marine environment as well as their bioactivity potential. They also evidence the importance of further investigating such fungal strains aiming at rele... / Mestre
27

Filogenia molecular e metabolismo secundário de espécies de Peperomia / Molecular phylogeny and secondary metabolism from Peperomia species.

Valero Gutiérrez, Lady Yasmin 02 September 2015 (has links)
Árvores evolutivas de espécies de Peperomia baseadas nas regiões de ITS e matK foram confrontadas com perfis metabólicos de extratos brutos obtidos por RMN 1H, HPLC-DAD e LC-ESI-MS. A análise de clusters (HCA) e a análise discriminante de componentes principais (DAPC) suportaram em parte os agrupamentos observados por ITS e matK. As principais classes de metabólicos secundários observadas foram policetídeos, meroterpenos, cromenos, fenilpropanoides e amidas, sendo que foram ainda isolados um policetídeo (malabaricona D) de P. megapotamica; o fenilpropanoide elemicina e a lignana tetraidrofurânica diyangambina de P. rotundifolia; e as flavonas 5,6,7-trimetoxiflavona e 4\',5,6,7- tetrametoxiflavona de P. sincorana. As PKS tipo chalcona sintase (CHS) de peperomias, diferiram daquelas de famílias filogeneticamente próximas como Myristicaceae (Virola) e Lauraceae (Aniba). Como muitos meroterpenos de espécies de Peperomia possuem como núcleo básico o ácido orselínico, produto típico de líquens e bactérias, o gene ácido orselínico sintase (OSAS) foi investigado nas plantas e nos 27 fungos endofíticos isolados de espécies de Peperomia (identificados pelas sequências de ITS1-5.8S-ITS2). Foram amplificadas pelo menos uma PKS (NR, HR e PR) em cada uma das linhagens e AOS em várias delas (UR1, UC3, UF1, UF2, UF3, UF4, GC3, NR1, NC1, NC2, NF1, AR1, AC1, AC4, OC1 e OF1). A homologia de 60% da OSAS amplificada de UR1 com a sequência de Streptomyces viridochromogenes é sugestivo de transferência horizontal de bactéria para fungos. / Phylogenetic tree of Peperomia species based on ITS and matK were compared to the metabolic profiling of crude extracts using 1H NMR, HPLC-DAD and LC-ESI-MS. Cluster analysis (HCA) and discriminant analysis of principal componentes (DAPC) supported significantly the clustering observed by ITS and matK. The major classes of secondary metabolites were polyketides, meroterpenes, chromenes, phenylpropanoids and amides and besides, one polyketide (malabaricone D) of P. megapotamica; the phenylpropanoid elemicin and the tetrahydrofuran lignan diyangambin from P. rotundifolia; and the flavones 5,6,7- trimethoxyflavone and 4\',5,6,7-tetramethoxyflavone were isolated from P. sincorana. The PKS chalcone synthase type (CHS) from peperomia, differed from phylogenetically related families Myristicaceae (Virola) and Lauraceae (Aniba). Since several meroterpenes from Peperomia species have the orsellinic acid as an aromatic core, typical of liquens and bacteria, the orsellinic acid (OSAS) was investigate in the plants and 27 endophytes isolated from Peperomia (identified based on ITS1-5.8S-ITS2 sequences). At least one PKS (NR, HR and PR) were isolated from each strains and AOS were isolated from several strains (UR1, UC3, UF1, UF2, UF3, UF4, GC3, NR1, NC1, NC2, NF1, AR1, AC1, AC4, OC1 and OF1). The 60% of homology observed for OSAS amplified from UR1 with that of Streptomyces viridochromogenes is suggestive of a horizontal transferring from bacteria to fungi.
28

Estudo de fungos endofíticos associados a plantas da família Asteraceae como fontes de metabólitos secundários e em processos de biotransformações / Studies of endophytic fungi found in association with species of Asteraceae as sources of secondary metabolites and on biotransformation processes.

Borges, Warley de Souza 04 July 2008 (has links)
Fungos endofíticos constituem uma fonte promissora e ainda pouco explorada de novas substâncias potencialmente bioativas, que podem ter aplicações na medicina, agricultura e biologia química. Neste trabalho foram isolados cinco fungos endofíticos das folhas de Tithonia diversifolia, os quais foram cultivados em pequena escala e avaliados em diversos bioensaios. O fungo endofítico Phoma sorghina foi cultivado em escala ampliada, produzindo nove substâncias, sendo três derivados antraquinônicos inéditos na literatura. Três fungos endofíticos associados à Viguiera robusta foram estudados. De Colletotrichum gloeosporioides foram isoladas oito substâncias, sendo um derivado dicetopiperazínico e um derivado aminoaçúcar inéditos na literatura. Diaporthe phaesolorum produziu três derivados dicetopiperazinicos, um inédito na literatura. Chaetomium globosum produziu treze substâncias, sendo oito derivados azaphilônicos inéditos. Algumas linhagens endofíticas foram avaliadas em experimentos de biotransformação de três naftoquinonas e da 1-tetralona, catalisando reações de oxidação e redução. O fungo Diaphorte phaseolorum catalisou uma reação de metilação inédita na literatura de biotransformação. / Endophytic fungi are a promising and untapped source of potential biologically active compounds that might be useful as therapeutic and agrochemical agents, or chemical biology tools. In this thesis five endophytic fungi were isolated from the leaves Tithonia diversifolia. All the strains have been cultivated in small scale and the extracts submitted to bioassays. The culture of the endophyte Phoma sorghina was scaled up, affording six known compounds and three novel anthraquinone derivatives. Three endophytes from Viguiera robusta have also been studied as sources of natural products. Colletotrichum gloeosporioides produced six known compounds, one novel aminosugar and one new diketopiperazine derivative. Diaporthe phaesolorum biosynthesized three diketopiperazine derivatives, one novel in the literature. Five known compounds and eight novel azaphilone derivatives were isolated from Chaetomium globosum. Some endophytic strains have been evaluated in biotransformation experiments of three naphthoquinones and 1-tetralone, catalyzing oxidation and reduction reactions. The endophyte Diaphorte phaseolorum catalyzed a novel methylation reaction in the biotransformation literature.
29

Prospecção química e biológica em fungos endofíticos associados a ´Viguiera arenaria´ (Asteraceae) / Chemical and biological prospection in endophytic fungi found in association with Viguiera arenaria (Asteraceae)

Guimarães, Denise Oliveira 10 February 2006 (has links)
Foram isolados 37 fungos endofíticos de Viguiera arenaria (VA1 a VA37), sendo 32 oriundos de folhas e 5 de raízes. Os fungos foram classificados por métodos de biologia molecular, sendo Glomerella cingulata a espécie predominante. Os fungos foram cultivados em culturas fermentativas em duas etapas, em pequena escala, para obtenção dos extratos em AcOEt, BuOH e MeOH. Os extratos em AcOEt foram avaliados em ensaios antimicrobianos, citotóxicos frente a células leucemia T humana (JURKAT) e frente às enzimas GAPDH de Trypanosoma cruzi e APRT de Leishmania tarentolae. Diversos extratos apresentaram atividades biológicas significativas. Os perfis químicos dos extratos em AcOEt foram avaliados através de CLAE-UV e RMN 1H. Os fungos VA1 (Glomerella cingulata) e VA17 (Fusarium sp.), selecionados após as triagens química e biológica, foram cultivados em escala ampliada. A partir do extrato AcOEt do fungo VA1 foram isoladas duas substâncias, nectriapirona (I) e tirosol (II). A nectriapirona apresentou atividade citotóxica significativa contra células de leucemia T humana (linhagens JURKAT) e melanoma (linhagens B16F10). Ergosterol (III) foi isolado do extrato micelial metanólico do fungo VA1. A partir do extrato micelial metanólico do fungo VA5 (G. cingulata), cultivado em pequena escala, foi isolado o manitol (IV). Após do cultivo em escala ampliada do fungo VA17 (Fusarium sp.) foram isolados três derivados dicetopiperazinícos, um oriundo do extrato AcOEt, substância V, ainda não relatada na literatura, e dois do extrato micelial MeOH, fusaperazina B (VI) e substância VII, também inédita na literatura. O isolamento das substâncias foi realizado através de técnicas cromatográficas, como CC, CCDP e CLAE. As estruturas químicas foram elucidadas com auxílio de técnicas espectroscópicas (RMN 1H e 13C, HMQC, HMBC, NOE-diff) e espectrométricas (ESI-MS). Experimentos de modelagem molecular foram realizados com a fusaperazina B (VI), que corroboraram com os dados de NOE-diff, indicando que a conformação dobrada do anel dicetopiperazínico é a mais predominante. Foi ainda realizada avaliação do perfil químico dos extratos obtidos em pequena escala dos fungos classificados como G. cingulata, via CLAE e RMN 1H, verificando-se diferenças químicas significativas, o que pode sugerir variabilidade genética entre as linhagens. O tirosol (II) foi detectado na maioria dos extratos de G. cingulata. / A total of 37 endophytic fungi were isolated from Viguiera arenaria (VA1 to VA37), 32 from the leaves and 5 from the roots. Endophytes were classified by means of molecular biology methods, and Glomerella cingulata was the predominant species. The endophytes were cultured in a two step fermentative process in small scale to give the EtOAc, BuOH and MeOH extracts. The EtOAc extracts were submitted to antimicrobial assays, citotoxic assays against human leukemia T cells (JURKAT) and assays against two enzymes, GAPDH from Trypanosoma cruzi and APRT from Leishmania tarentolae. Several extracts showed promising activities in the bioassays. The chemical profiles of the EtOAc extracts were obtained through HPLC and 1H NMR. Endophytes VA1 (Glomerella cingulata) e VA17 (Fusarium sp.) were cultured in large scale after chemical and biological screenings. Nectriapyrone (I) and tirosol (II) were isolated from the EtOAc extract from VA1. Nectriapyrone showed high citotoxicity against leukemia T human cells (JURKAT) and melanoma cells (B16F10). Ergosterol (III) was isolated from the micelial MeOH extract of VA1. Mannitol (IV) was isolated from the micelial MeOH extract from the fungus VA5 (G. cingulata). Extracts from VA17 (Fusarium sp.), obtained in large scale, yielded three diketopiperazine derivatives. A novel derivative was isolated from the EtOAc extract (compound V). Two derivatives were obtained from the micelial MeOH extract, fusaperazine B (VI) and a new diketopiperazine (VII). The isolation of the compounds was carried out using chromatography techniques (column, prep. TLC, and HPLC) and the identification was achieved by spectroscopic (1D and 2D NMR) and spectrometric methods (ESI-MS). Molecular modeling experiments were carried out with fusaperazine B (VI), showing that the diketopiperazine ring is predominantly in the folded conformation, in agreement with NOE-diff experiments. Significant differences were observed in the HPLC profiles and 1H NMR spectra of the extracts from the G. cingulata strains, which might be related to genetic variability among the strains. Tirosol (II) was detected in the majority of G. cingulata extracts
30

Estudo químico e avaliação da atividade antimicrobiana de fungos endofíticos associados à Paepalanthus chiquitensis (eriocaulaceae) e efeitos de moduladores químicos epigenéticos no cultivo de Pochonia chlamydosporia /

Hilário, Felipe. January 2016 (has links)
Orientador: Lourdes Campaner dos Santos / Coorientador: Taís Maria Bauab / Banca: Daniel Rinaldo / Banca: Rosemeire Cristina Linhari Rodrigues Pietro / Resumo: Este trabalho apresenta os resultados da pesquisa de metabólitos secundários ativos produzidos por fungos endofíticos associados às partes aéreas (folhas, escapos e capítulos) de Paepalanthus chiquitensis (Eriocaulaceae). Entre os 25 fungos isolados da espécie de Eriocaulaceae, o Fusarium sp. foi o fungo mais promissor quanto à atividade antimicrobiana para as cepas de bactérias Gram-negativa Escherichia coli e Salmonella setubal, da bactéria Gram-positiva Staphylococus aureus e para a levedura Candida albicans resistente ao fluconazol, e ainda exibiu a capacidade bactericida e fungicida. Outro fungo selecionado foi o Bipolaris sp. isolado das folhas de P. chiquitensis devido a sua diversidade química. O cultivo dos fungos em Potato Dextrose Broth (PDB) em escala ampliada resultou no extrato acetato de etila (EAcOEt) que foram purificados por métodos cromatográficos em escala preparativa. A identificação/elucidação por métodos espectrométricos e espectroscópicos (EM, IV, UV, RMN mono e bidimensionais) forneceu as substâncias: 3,4-Piridinadiamina, N4-1-metil-5-(3'-buten-1-il) (S1), ácido fusárico (S2), 2-(1H-indol-6-il)-acético (S3), 2-Piridinametilamina-N8-metil-5-hexanoato (S4) e o sesterterpeno terpestacina (S5), Etanoato de etila-2-(2-acetil-4,6-diidroxifenil) (B4) e um alcalóide inédito na literatura (B1). Com este trabalho, observamos que os fungos endofíticos estudados possuem sua química completamente distinta quando comparada com as classes de substâncias isoladas de espécies vegetais de Eriocaulaceae, sendo uma importante fonte de novos produtos naturais com potencial atividade biológica. Este trabalho contempla também o estudo dos efeitos de modificadores epigenéticos e íons metálicos na diversificação metabólica do fungo Pochonia chlamydosporia (ATCC)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work presents the results of the research of active secondary metabolites produced by endophytic fungi associated with the aerial parts (capitulae, scapes and leaves) of Paepalanthus chiquitensis (Eriocaulaceae). Among the 25 species of fungi isolated from the specie of Eriocaulaceae, the Fusarium sp. was the fungus that showed the best biological activity against the strains of Gram-negative bacteria Escherichia coli and Salmonella setubal, the Gram-positive bacterium Staphylococus aureus and Candida albicans yeast resistant to fluconazole. The Fusarium sp also displayed bactericidal and fungicidal effects. The research also presents the chemical studies of the fungus Bipolares sp., isolated from the leaves of P. chiquitensis which was selected due to its chemical profile. The large scale cultivation of both fungi afforded the respective ethyl acetate extracts which were purified by preparative chromatography methods. The chemical structures were elucidated by spectrometric and spectroscopic methods (MS, IR, UV, mono- and bidimensional NMR affording the following substances from the Fusarium sp.: 5-(but-3-en-1-yl)-N4-methylpyridine-3,4-diamine (S1), fusaric acid (S2), 2-(1H-indol-6-yl)-acid (S3), 5-Butil-2-pyridinecarboxamide (S4) and the sesterterpene fusaproliferin (S5), while for the Bipolaris sp.: Acetic acid, (2-acetyl-3,5-dihydroxyphenyl)-, ethyl ester (B4) and a new alkaloid (B1). Herein, we also showed the study of the effects of epigenetic modifiers and metal ions in metabolic diversity from the fungus Pochonia chlamydosporia (ATCC). The presence of anacardic acid in the liquid medium afforded 2.6 times more ethyl acetate extract compared with the PDB (Potato Dextrose Broth) control. Besides, the analysis by analytical HPLC... (Complete abstract click electronic access below) / Mestre

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