Made available in DSpace on 2016-08-19T12:56:37Z (GMT). No. of bitstreams: 1 Francisco Reivilandio.pdf: 1587328 bytes, checksum: 64f5702f7917c2248cddce09472cef03 (MD5) Previous issue date: 2011-06-10 / Jamaican pepper, Pimenta dioica Lindl, is a species belonging to the family of Myrtacea, measuring 6m to 15m high, very aromatic in all its parts. It is originally from Central America and West India and with great economic importance in the market of essential oils. The extraction of the essential oil of Pimenta dioica L seeds was carried out by using the method of hydrodistillation known as Cleverger system. It was extracted from a maximum volume of oil in the period of four hours with a yield of 2.8% m/m. The UV spectrophotometric techniques, mass spectrometry and gas chromatography, as well as the physical constants, density, color and appearance were used to identify the compound eugenol and other constituents of the essential oil of P. dioica L. Through the technique of external standard and standard addition it was quantified with a eugenol percentage of 76.98%, forming the major component. The essential oil of Pimenta dioica L was applied to the phyto pathogenic fungi species Fusarium oxysporum f. sp. lycopersici, Fusarium oxysporum f. sp. passiflorae, Fusarium subglutinans f. sp ananas., Fusarium oxysporum f. sp. vasinfectum and Fusarium oxysporum f. sp. cubense resulting in a total inhibition of mycelial growth of all species tested for a period of ten days of evaluation. / A pimenta da Jamaica, Pimenta dioica Lindl, é uma espécie vegetal pertencente à família Mirtacea, medindo de 6 a 15 m de altura, muito aromática em todas as suas partes. É originaria da América Central e Oeste da Índia e com grande importância econômica no mercado de óleos essenciais. A extração do óleo essencial das sementes da P. dioica foi realizada pelo método da hidrodestilação utilizando o sistema Cleverger. Foi extraído um volume máximo de óleo no tempo de quatro horas com um rendimento de 2,8 %m/m. As técnicas espectrofotométricas de UV, espectrometria de massa e cromatografia gasosa, assim como as constantes físicas, densidade, cor e aparência foram utilizadas para identificar o composto eugenol e os demais constituintes do óleo essencial da P. dioica. Através da técnica de padrão externo e adição de padrão quantificou-se o eugenol com um percentual de 76,98 %, constituindo-se o componente majoritário. O óleo essencial da P. dioica foi aplicado em fungos fitopatogênicos das espécies Fusarium oxysporum f. sp. lycopersici, Fusarium oxysporum f. sp. passiflorae, Fusarium subglutinans f. sp. ananas, Fusarium f. sp. vasinfectum e Fusarium oxysporum f. sp. cubense, obtendo-se uma inibição total do crescimento micelial de todas as espécies testadas por um período de dez dias de avaliação.

O uso de plantas na cura de enfermidades tem sido objeto de muitos estudos e desde épocas remotas está ligado ao desenvolvimento cultural de civilizações. Estudos anteriores em espécies de Myristicaceae descrevem a ocorrência da classe de lignóides como principal metabólito secundário. Variedades de estruturas químicas e de atividades biológicas são atribuídas aos lignóides. Estes metabólitos encontram-se acumulados em todas as partes da planta, principalmente nos frutos, onde os compostos predominantes são neolignanas. O presente trabalho foi realizado com Virola molissima que se encontra dispersa na Reserva Adolpho Ducke, situada nas proximidades de Manaus-AM. Os frutos foram coletados durante o mês de novembro, estação de seca na região. Não existe registro de estudo fitoquímico desta espécie. A partir de extratos de pericarpos, arilos, tegumentos e amêndoas dos frutos da Virola molissima foram isoladas por fracionamento cromatográfico as neolignanas tetrahidrofurânica, ariltetralônica e diarilbutânica. As neolignanas isoladas foram identificadas por comparação de seus dados de Ressonância Magnética Nuclear de Hidrogênio e de Carbono Treze, com aqueles descritos na literatura. A atividade antifúngica da neolignana ariltetralônica, pura ou em mistura, foi testada contra basidiomicetos Pycnoporus sanguineus, Trametes villosa e Lenzites trabeas. Estes fungos são xilófagos e causam o apodrecimento da madeira. / The use of plants in the treatment of diseases has been object of many studies, and since remote ages, the issue is linked to the cultural development of civilizations. Previous studies on Myristicaceous species described the occurrence of lignoids as its main secondary metabolites, which are known by varieties of chemical structures and biological activities. These lignoids are accumulated in all parts of the plant, mainly in the fruits, where the major constituent are neolignans. Present work was carried out on Virola molissima dispersed in Adolpho Ducke Reserve, located around Manaus, Amazon State, Brazil. Its fruits were collected during November, a month of dry season in this region. This species has not been phytochemically studied. Tetrahydrofuran, aryltetralone and dibenzylbutane neolignans were isolated from the extracts of pericarps, arils, seed coats and seeds of V. molissima fruits, by chromatographic fractionations. The structures of the isolated neolignans were elucidated through a Nuclear comparison between Magnetic Resonance of 1Hidrogen and 13Carbon data, and those described in the literature. The antifungal activity of the aryltetralone neolignan, pure or in mixture, was assayed against basidiomycetes Pycnoporus sanguineus, Trametes villosa and Lenzites trabeas. These fungi are xylophagus and they cause the decay of the wood.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-04-15T19:16:37Z No. of bitstreams: 1 edilenebolutaribaptista.pdf: 6189497 bytes, checksum: 9b5a9896c31c59b43d9001520bb0f8c9 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-04-24T03:18:16Z (GMT) No. of bitstreams: 1 edilenebolutaribaptista.pdf: 6189497 bytes, checksum: 9b5a9896c31c59b43d9001520bb0f8c9 (MD5) / Made available in DSpace on 2016-04-24T03:18:16Z (GMT). No. of bitstreams: 1 edilenebolutaribaptista.pdf: 6189497 bytes, checksum: 9b5a9896c31c59b43d9001520bb0f8c9 (MD5) Previous issue date: 2015-12-11 / As dermatofitoses são doenças fúngicas que nos animais são causadas principalmente por microrganismos dos gêneros Microsporum spp e Trichophyton spp. Afetam os tecidos queratinizados resultando no aparecimento de lesões em anel e alopecia e podem ser transmissíveis ao homem. Na busca por tratamentos naturais alternativos aos fármacos sintéticos de toxicidade conhecida, os óleos essenciais destacam-se por possuírem uma composição química complexa e diversas ações farmacológicas conhecidas. O objetivo do presente trabalho foi desenvolver uma formulação veterinária de uso tópico com óleo essencial para tratamento da dermatofitose e avaliar a sua estabilidade. Foram realizadas a caracterização morfológica dos fungos Trichophyton mentagrophytes ATCC 11480, Microsporum canis ATCC 32903 e Microsporum gypseum ATCC 14683; a identificação e quantificação dos componentes químicos dos óleos essenciais da Pimenta pseudocaryophyllus (Gomes) L.R. Landrum e do Eucalyptus smithii e, posteriormente, a análise de seus potenciais antifúngicos. Uma formulação tópica (creme aniônico tipo O/A) com o óleo da P. pseudocaryophyllus foi desenvolvida e submetida a 50 °C e 90% de Umidade Relativa - UR por 3 meses para o estudo de estabilidade acelerada. Durante esse período, foram avaliados os parâmetros organolépticos e físico-químicos da formulação, além do estudo termoanalítico, espectroscópico na região do infravermelho e de cromatografia gasosa (CG). Os resultados para a P. pseudocaryophyllus foram mais promissores indicando uma concentração inibitória mínima (CIM) de 250 μg/mL para os três fungos e uma concentração fungicida mínima (CFM) de 250 μg/mL para o M. canis e de 1000 μg/mL para T. mentagrophytes e M. gypseum. A formulação contendo o óleo da P. pseudocaryophyllus na concentração de 1% (m/m) mostrou-se eficaz no combate fúngico e, por meio da microscopia eletrônica de varredura (MEV), foram observadas as principais alterações morfológicas nas hifas e macroconídeos dos fungos causadas pelos óleos e pela formulação. Durante o estudo de estabilidade a formulação manteve-se estável em relação aos parâmetros organolépticos e físicoquímicos, apresentando apenas uma perda na concentração de eugenol (composto majoritário do óleo essencial) comprovada por CG. Por meio de técnicas termoanalíticas foi possível verificar a estabilidade térmica e avaliar a compatibilidade entre os excipientes e o óleo essencial. De forma geral, os resultados encontrados para a formulação foram satisfatórios, porém vale ressaltar que os estudos termoanalíticos ainda não substituem os estudos convencionais de estabilidade e que para avaliar a real toxicidade dessa formulação, testes de segurança precisam ser realizados antes da comercialização do produto. / Dermatophytosis are fungal diseases and they are caused in animals by microorganisms of the genus Microsporum spp and Trichophyton spp. Tissues containing keratin are affected resulting in ring lesions and alopecia and it can be transmitted to humans.Trying to find alternative natural treatments, the essential oils are notable for having a complex chemical composition and many known pharmacological actions. The objective of this study was to develop a veterinary formulation for topical use with essential oil to treat the dermatophytosis and evaluate its stability. A morphological characterization of the fungi Trichophyton mentagrophytes ATCC 11480, Microsporum canis ATCC 32903 and Microsporum gypseum ATCC 14683 was performed and also the identification and quantification of chemical components of the essential oils of Pimenta pseudocaryophyllus (Gomes) L.R. Landrum and the Eucalyptus smithii and, subsequently , the analysis of their potential antifungal. A topical formulation (anionic cream type O/A) with the oil of P. pseudocaryophyllus was developed and submitted to 50 °C and 90% relative humidity for 3 months to study of accelerated stability. During this period, physical, chemical and organoleptic parameters of the formulation were evaluated, in addition to thermoanalytical, infrared spectroscopic and gas chromatography (GC) study. The results for P. pseudocaryophyllus were more promising indicating a minimum inhibitory concentration (MIC) of 250 μg mL-1 for all three fungi and minimum fungicidal concentration (MFC) of 250 μg mL-1 for M. canis and 1000 μg mL-1 for T. mentagrophytes and M. gypseum. The formulation containing the oil of P. pseudocaryophyllus with a concentration of 1% (w/w) was effective in combating fungal and, by scanning electron microscopy (SEM), the main morphological changes in hyphae and fungal macroconidia caused by oils and the formulation were observed. During stability study, the formulation was stable in relation to physical, chemical and organoleptic parameters, with only a loss in eugenol concentration (major compound of the essential oil) confirmed by GC. It was possible to verify, by thermoanalytical techniques, the thermal stability and to evaluate the compatibility of the excipients and the essential oil. In general, the results of formulation were satisfactory, but it´s important to emphasize that the thermoanalytical studies does not replace conventional stability studies. To evaluate the real toxicity of this formulation, safety tests need to be performed before to marketing the product.

Made available in DSpace on 2014-08-20T14:38:01Z (GMT). No. of bitstreams: 1 tese_isabel_madrid.pdf: 2158071 bytes, checksum: 0cdf6bd60773cb623d04e6df539e8aa9 (MD5) Previous issue date: 2011-02-25 / Sporotrichosis has been receiving attention in any world in the several areas of the health as an important fungal disease. So, this work aimed: (i) to study cases of sporotrichosis diagnosed in the south region of Rio Grande do Sul in a period of ten years, (ii) to study the morphological and pathogenicity characteristics of S. schenckii isolates, (iii) to determine the sensitivity of S. schenckii isolates to the commercial disinfectants. Sporotrichosis cases were analysed as for geographical distribution, it clinical forms of the disease, presence of the fungus in different anatomical sites and tecidual inflammatory response. The 42 S. schenckii isolates originating from clinical cases, environment isolates and reference strains used in the phenotypic study were evaluated as for macromorphology in Sabouraud agar added of chloramphenicol, potato agar and ágar lactrimel, incubated 25ºC and 35ºC for 21 days. The micromorphology was analyzed in potato agar to 25ºC whereas the termotholerance was evaluated in ágar Sabouraud added of 1% yeast extract, incubated 41ºC for seven days. Ultraestructural study of nine clinical isolates and two reference strains of S. schenckii were carried by transmission electron microscopy. Susceptibility of 12 S. schenckii isolates to disinfectants was performed by the techniques of broth microdilution, agar diffusion and direct exposute test. The 103 cases of sporotrichosis in animals demonstrated that this is an endemic mycosis in the south region of Rio Grande do Sul being more frequent in young felines and adult dogs. The felines developed disseminated cutaneous form with more frequency. Therefore, in canines, the fixed cutaneous form was predominant though it has taken place in 18.2% of the dog to respiratory form with absence of cutaneous lesions. Research of the S. schenckii in nails, oral cavity, conjunctival mucosa, blood and testicles demonstrated high fungal positivity in samples of oral cavity (45.2%) and testicles (46.6%). The study of the hematological alterations related with the clinical form of the disease demonstrated that animals with the cutaneous fixed form of the mycosis do not present alterations in the blood count. However, animals with the cutaneous disseminated form develop important alterations characterized mainly for leucocytosis with neutrophilia and anaemia. Morphological analyzes of 42 clinical and environmental isolates of S. schenckii demonstrated macro and micromorphogical differences in the different culture medium utilized. In the thermotolerance evaluation 26.2% isolates were capable of growth at 41oC, specially isolates of feline sporotrichosis. The ultraestructural study showed presence of granules of melanin in all S. schenckii isolates of canine sporotrichosis and correlation among melanin and cell wall thickness. In vitro evaluation of disinfectants demonstrated chlorexidine digluconate antifungal activity in the microdilution broth and agar diffusion techniques and the sodium hypochlorite showed best performance in the direct exposure test. The presence of the organic matter interfered in the antifungal action of both disinfectants. Sodium hypochlorite showed better results with total elimination of the fungal load in the absence of organic matter and a reduction of 60 % of the fungal load in the presence of this. / A esporotricose tem se destacado mundialmente nas diversas áreas da saúde como uma importante doença fúngica. Assim, este trabalho teve como objetivos: (i) estudar casos de esporotricose diagnosticados na região sul do Rio Grande do Sul num período de dez anos, (ii) estudar as características morfológicas e de patogenicidade de isolados de Sporothrix schenckii, (iii) determinar a suscetibilidade de S. schenckii a desinfetantes comerciais. Os casos de esporotricose foram analisados quanto a distribuição geográfica, forma clíinica da doença, presença do fungo em diferentes sítios anatômicos e resposta tecidual. Os 42 isolados de S. schenckii provenientes de casos clínicos, isolados do ambiente e cepas de referência utilizados no estudo fenotípico foram avaliados quanto a macromorfologia em ágar Sabouraud acrescido de cloranfenicol, ágar batata e ágar lactrimel incubados a 25ºC e 35ºC por 21 dias. A micromorfologia foi avaliada em ágar batata a 25ºC enquanto que a termotolerância foi avaliada em ágar Sabouraud acrecido de extrato de levedura 1% incubado a 41ºC por sete dias. O estudo ultraestrural dos nove isolados clínicos e duas cepas de referência de S. schenckii foi realizado por microscopia eletrônica de transmissão. A suscetiblidade de 12 isolados de S. schenckii a desinfetantes foi realizada pelas técnicas de microdiluição em caldo, difusão em agar e teste de exposição direta. Os 103 casos de esporotricose em animais demonstraram que esta é uma micose endêmica na região sul do Rio Grande do Sul ocorrendo com mais freqüência em felinos jovens e cães adultos. Os felinos desenvolveram principalmente a forma cutânea disseminada enquanto que em caninos, a forma cutânea fixa foi a mais freqüente embora tenha ocorrido em 18,2% dos caninos, a forma respiratória com ausência de lesões cutâneas. A pesquisa do fungo S. schenckii em unhas, cavidade oral, mucosa conjuntival, sangue e testículos revelou alta positividade fúngica em amostras de testículos (46,6%) e cavidade oral (45,2%). O hemograma de animais com a forma cutânea fixa não apresentou alterações nos valores hematológicos enquanto que aqueles com a forma cutânea disseminada apresentaram alterações tanto no leucograma como no eritrograma, caracterizadas por leucocitose por neutrofilia e anemia normocítica e normocrômica. A análise morfológica de 42 isolados clínicos e do ambiente de S. schenckii demonstrou diferenças macro e micromorfológicas nos diferentes meios de cultivo utilizados. Na avaliação da termotolerância obteve-se 26,2% dos isolados termotolerantes, sendo a maioria proveniente de casos de esporotricose felina. O estudo ultraestrutural revelou presença de grânulos de melanina em todos os isolados de S. schenckii originados de esporotricose canina e correlação entre presença de melanina e espessura da parede celular. A avaliação in vitro de desinfetantes demonstrou maior ação antifúngica do digluconato de clorexidina nas técnicas de microdiluição em caldo e difusão em agar enquanto que o hipoclorido de sódio apresentou melhor eficácia na técnica de exposição direta. A presença de matéria orgânica interferiu na ação antifúngica de ambos os desinfetantes, entretanto, o hipoclorito de sódio apresentou melhores resultados com inativação total da carga fúngica na ausência de matéria orgânica e redução de 60% da carga fúngica na presença desta.

Orientadores: Telma Teixeira Franco, Carlos Raimundo Ferreira Grosso / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-07T12:03:40Z (GMT). No. of bitstreams: 1 OliveiraJunior_EnioNazarede_D.pdf: 5260922 bytes, checksum: 838753bbbf60bb35edf5aeb62dbbc33e (MD5) Previous issue date: 2006 / Resumo: Na primeira etapa deste trabalho foi feita uma revisão de literatura referente à atividade antifúngica de quitina, quitosana e seus derivados contra diferentes tipos de microrganismos, como bactérias, fungos e leveduras. Nesta revisão são descritos importantes desenvolvimentos relativos a aplicação de quitosana e seus derivados como substância antimicrobiana contra bactérias, fungos e leveduras, hipóteses envolvidas na suas atividades antimicrobianas e efeitos na qualidade e armazenagem de vegetais frescos tratados com quitosana e seus derivados. A segunda etapa deste trabalho se refere a produção e caracterização de quitosanas com diferentes graus de polimerização (DP) obtidas por tratamento térmico e quitosanas com diferentes graus de acetilação (FA) obtidas por desacetilação alcalina. A terceira etapa deste trabalho refere-se à avaliação dos efeitos da atividade antifúngica de quinze amostras de quitosana com diferentes graus de polimerização e diferentes graus de acetilação contra quatro fungos fitopatogênicos (Alternaria alternata, Botrytis cinerea, Penicillium expansum e Rhizopus stolonifer). Os crescimentos fúngicos foram avaliados em micro placas de 96 reservatórios e medidos em leitor de microplacas. A atividade antifúngica de quitosana aumentou com o decréscimo do FA. O efeito da combinação de quitosana com menor FA e maior DP teve a mais alta atividade fungistática contra os fungos A. alternata e B. cinerea. Os resultados tendem a indicar que os grupamentos amino protonados (NH3 +) foram um importante fator envolvido no efeito antifúngico. Os fungos mais resistentes foram Penicillium expansum e Botrytis cinerea e os mais sensíveis foram Alternaria alternata e Rhizopus stolonifer. Na quarta etapa deste trabalho foi investigado o efeito de quitoligômeros no crescimento dos mesmos fungos analisados na terceira etapa. Verificou-se que misturas de quitoligômeros de DP 5 a 8, DP 2 a 12 e de DP 2 a 11, apresentaram baixo ou nenhum efeito no crescimento fúngico na concentração máxima de 1,000 µg × mL-1. A última etapa deste trabalho refere-se às mudanças morfológicas nas hifas dos fungos tratados com quitosana. As micrografias obtidas por microscopia eletrônica de varredura com emissão de campo mostraram que os micélios fúngicos tratados com quitosana estavam agregados, excessivamente ramificados, inchados e de comprimentos reduzidos / Abstract: In the first step of this work, a literature review concerning antimicrobial activity of chitin, chitosan and their derivatives against different groups of microorganisms, such as bacteria, yeast and fungi was made. Important developments related to applications of chitosan and their derivatives, as an antimicrobial substance against bacteria, fungi and yeasts, hypotheses involved in the antimicrobial activities and effects on storability and quality of fresh vegetables treated with chitosan and its derivatives are described in this present review. The second step of this work, concerns the production of chitosans with different degrees of polymerization (DP) by thermal treatment and chitosans with different degrees of acetylation (FA) by alkaline deacetylation. The third step of this work, concerns the evaluation of antifungal effects of fifteen chitosans with different degrees of polymerization and different degrees of acetylation against four phytopathogenic fungi (Alternaria alternata, Botrytis cinerea, Penicillium expansum and Rhyzopus stolonifer) by using the 96-well microtiter plate and a microplate reader. Antifungal activity of chitosans increased with FA decreasing. Combination effect of chitosan with low FA and high DP showed the highest fungistatic activity against A. alternata and B. cinerea. The results indicated that free amino groups protonated (NH3 +) were an important factor for antifungal effect. The most resistant fungi were Penicillium expansum and Botrytis cinerea and the most sensitive fungi were Alternaria alternata and Rhizopus stolonifer. In the fourth step of this work, it was investigated the effect of chitooligomers in the fungal growth of the same target fungi analyzed in the third step. The results suggested that chitooligomer mixtures of DP 5 to 8, DP 2 to 12 and DP 2 to 11 showed low or no effect on the fungal growth at concentration of 1,000 µg × mL-1. The last step of this work, concerns the morphological changes on hyphae of fungi treated with chitosan. Mycelial aggregation and morphological structural changes as excessive branching, swelling of the cell wall and hyphae size reduction were observed in the micrographs obtained by scanning electron microscopy field emission / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-01-27T09:53:10Z No. of bitstreams: 1 camilasoaresfurtadocouto.pdf: 1669181 bytes, checksum: 87973d12c5cb4fed37df8f6a9afc5413 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-01-27T11:08:10Z (GMT) No. of bitstreams: 1 camilasoaresfurtadocouto.pdf: 1669181 bytes, checksum: 87973d12c5cb4fed37df8f6a9afc5413 (MD5) / Made available in DSpace on 2016-01-27T11:08:10Z (GMT). No. of bitstreams: 1 camilasoaresfurtadocouto.pdf: 1669181 bytes, checksum: 87973d12c5cb4fed37df8f6a9afc5413 (MD5) Previous issue date: 2014-07-10 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A esporotricose é uma importante micose subcutânea, que pode afetar seres humanos e animais, cujo principal agente etiológico é o Sporothrix schenkii. O tratamento de micoses vem sendo motivo de preocupação, devido à ocorrência de recidivas e surgimento de linhagens resistentes aos antifúngicos convencionais (sintéticos). Desta forma, há uma crescente busca por novos fármacos de origem sintética ou oriundo de fontes naturais eficazes e com novos mecanismos de ação. O objetivo deste trabalho foi identificar os componentes dos óleos essenciais de Baccharis trimera e Origanum vulgare por meio da cromatografia gasosa, investigar seus potenciais antifúngicos in vitro frente a quatro linhagens de Sporothrix schenckii e duas de S. brasiliensis. A anfotericina B e o cetoconazol foram utilizados como fármacos de referência. Os ensaios antifúngicos foram realizados por meio da triagem microbiológica e estabelecidas as concentrações inibitórias mínimas (CIM) e fungicidas mínimas (CFM) para as substâncias de interesse. A análise cromatográfica do óleo essencial de B. trimera demonstrou que o β-pineno (23,4%) foi o componente majoritário e no óleo de O. vulgare foi o γ-terpineno (30,5%) . Os valores de CIM e de CFM para o óleo de B. trimera e O. vulgare foram, respectivamente, 125 μg/mL e 62,5 μg/mL para a linhagem A; 500 μg/mL e 62,5 μg/mL para a linhagem B; 125 μg/mL e 125 μg/mL para o isolado S. schenckii ATCC 1099-18; 32,25 μg/mL e 125 μg/mL para o S. brasiliensis ATCC 5110; 62,5 μg/mL e 250 μg/mL para S. brasiliensis IPEC 17943 e 125 μg/mL e 500 μg/mL para o S. schenckii IPEC 15383. A ação dos dois óleos essenciais foi caracterizada como fungicida. Através das imagens de microscopia eletrônica de varredura (MEV), pode ser observado que os óleos essenciais provocam os mesmos tipos de alterações que os fármacos de referência, e em alguns casos em maior intensidade. Os resultados obtidos até o momento revelaram-se promissores e estimulam a continuidade da pesquisa. / Sporotrichosis is an important subcutaneous mycosis, that can affect humans and animals, which is the main etiological agent Sporothrix schenkii. The treatment of fungal infections has been of concern due to the occurrence of relapses and the emergence of strains resistant to conventional antifungal drugs (synthetic). Thus, there is a growing search for new and effective natural products with novel mechanisms of action. The objective was to identify the components of the essential oils of Origanum vulgare and Baccharis trimera and investigate their potential antifungal in vitro against four strains of S. schenckii and two of S. brasiliensis. Amphotericin B and ketoconazole were used as reference drugs. Antifungal assays were performed by means of microbiological screening and established the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) for the substances of interest. The chromatographic analysis of the essential oil of B. trimera demonstrated that β - pinene (23.4%) was the major component and in O. vulgare oil was the γ - terpinene (30.5%) . The MIC and MFC values for oil B. trimera and O. vulgare were, respectively, 125 μg/mL and 62.5 μg/mL for strain A; 500 μg/mL and 62.5 μg/mL for strain B; 125 μg/mL e 125 μg/mL for S. schenckii ATCC 1099-18; 32.25 μg/mL and 125 μg/mL for strain S. brasiliensis ATCC 5110; 62.5 μg/mL and 250 μg/mL for S. brasiliensis IPEC 17943; 125 μg/mL and 500 μg/mL for S. schenckii IPEC 15383. The action of the essential oil was characterized as a fungicide. Through the images of scanning electron microscopy may be noted that the essential oils cause the same kinds of changes that reference drugs, and in some cases greater intensity. The results obtained so far have shown promise and stimulate continuing research.

The increased use of antibiotics, antifungal agents and disinfectants in the last decades has resulted in development of microbial resistance to these drugs. Candida species are the fourth most common cause of hospital-acquired bloodstream infection and kill 40% of those patients. Natural antimicrobial peptides are promising candidates for the development of new agents to treat yeast and bacterial infections, as their presumed mechanism of action differs significantly from the mechanism of action of current drugs. This work is focused on several peptides isolated from the venom of wild bees and their synthetic analogues and the identification of the most effective ones against non-pathogenic Saccharomyces cerevisiae and several pathogenic Candida species. Antifungal activity of eight cationic antimicrobial peptides was tested and compared under various conditions. The overall susceptibility of pathogenic yeast species to currently used antifungal drugs and the antimicrobial peptides was screened with the aim to identify potential synergistic and species-specific effects. The effect of antimicrobial peptides on membrane potential was measured by a fluorescent probe (diS-C3(3)), and the relative hyperpolarization of plasma membrane was shown for each peptide. The effect of antimicrobial peptides on...

The continuous emergence of drug-resistance pathogens is a global concern. As a result, substantial effort is being expended to develop new therapeutics and mechanisms for controlling microbial growth to avoid entering a "post-antibiotic" era in which commonly used antibiotics are no longer effective in treating infections. In this work, we investigate the efficacy and application of ceragenins as non-peptide mimics of antimicrobial peptides (AMPs). First, this work examines the susceptibility of drug-resistant Gram-negative bacteria. The susceptibility of colistin-resistant clinical isolates of Klebsiella pneumoniae to ceragenins and AMPs suggests that there is little to no cross-resistance between colistin and ceragenins/AMPs. Furthermore, Lipid A modifications are found in bacteria with modest changes in susceptibility to ceragenins and with high levels of resistance to colistin. Next, we investigated the potential for cross resistance between chlorhexidine, colistin, AMPs and ceragenins as repeated exposure of bacteria to chlorhexidine might result in cross resistance with colistin, AMPs or ceragenins. Furthermore, a proteomics study on the chlorhexidine-resistant strains showed that chlorhexidine resistance is associated with upregulation of proteins involved in the assembly of LPS for outer membrane biogenesis and virulence factors in Pseudomonas aeruginosa.Second, this dissertation describes the antifungal activity of ceragenins against an emerging multidrug-resistant fungus, Candida auris. We found that lead ceragenins displayed activities comparable to known antifungal agents against C. auris isolates. We also found that fungal cell morphology was altered in response to ceragenin treatment, that ceragenins exhibited activity against sessile organisms in biofilms, and that gel and cream formulations including CSA-44 and CSA-131 resulted in a significant log reduction against established fungal infections in ex vivo mucosal tissues. Finally, a hydrogel film containing CSA-131 was generated on endotracheal tubes (ETTs). ETTs provide an abiotic surface on which bacteria and fungi form biofilms that cause serious infections. In this study, the eluting ceragenin prevented fungal and bacterial colonization of coated ETTs for extended periods while uncoated tubes were colonized by bacteria and fungi. Coated tubes were well tolerated in intubated pigs. The ability of ceragenins to eradicate established biofilms make them attractive potential therapeutics for persistent infections in the lung, including those associated with cystic fibrosis. In ex vivo studies, we initially found that this ceragenin, at concentrations necessary to eradicate established biofilms, also causes loss of cilia function. However, by formulating CSA-131 in poloxamer micelles, cilia damage was eliminated and antimicrobial activity was unaffected. These findings suggest that CSA-131, formulated in micelles, may act as a potential therapeutic for polymicrobial and biofilm-related infections in the lung and trachea.

Validamycin A (Val-A) is an aminoglycoside's antibiotic with anti-fungal activity. Val-A synthesized by Streptomyces hygroscopicus strain depending on the growth and development of this actinomyces. In this study, the effects of Mn and Zn on the antifungal activity and biomass of the Streptomyces hygroscopicus were conducted. The results showed that micronutrients Mn, Zn had significant effects on biomass as well as antifungal activity of strain Streptomyces hygroscopicus- DA15. With the addition of Mn at a concentration of 1μg/l of the nutrient medium, biomass of Streptomyces hygroscopicus was 2.85±0.02g/ml, the anti-fungal Rhizoctoniasolani (R. solani) round diameter reached 3.5±0.2cm. With the addition of Zn=3μg/l of the nutrient medium, biomass of Streptomyces hygroscopicus DA15 was 4.5±0.02g/ml, the anti-fungal R. solani round diameter reached 3.4±0.2cm. / Validamycin A (val-A) là một loại kháng sinh có khả năng kháng nấm, được tổng hợp bởi xạ khuẩn Streptomyces hygroscopicus và phụ thuộc vào quá trình sinh trưởng, phát triển của xạ khuẩn. Bài báo này đánh giá ảnh hưởng của nguyên tố vi lượng Mn, Zn đến hoạt tính kháng nấm Rhizoctonia solani (R. solani) và sinh khối của chủng Streptomyces hygroscopicus DA15. Khi bổ sung Mn vào môi trường nuôi cấy với nồng độ 1μg/l, sinh khối của Streptomyces hygroscopicus- DA15 đạt 2,85±0,02g/ml, đường kính vòng kháng nấm đạt 3,5±0,2cm. Bổ sung Zn vào môi trường nuôi cấy với hàm lượng Zn=3μg/l, sinh khối của Streptomyces hygroscopicus DA15 đạt 4,5±0,02g/ml và đường kính vòng kháng nấm đạt 3,4±0,2cm.

Ce travail de thèse a permis de décrire la contamination importante des grains du café de (Coffea canephora variété robusta) par des moisissures au cours des traitements post récolte des cerises de café par la voie sèche, dans une zone tropicale humide. La stratégie d’échantillonnage mise en place à consister à faire des prélèvements durant deux années successives (2008 et 2009) sur des sites localisés dans les principales zones de production du café en Côte d’Ivoire. A partir de 31 échantillons de cerises, grains et coques de café, 218 souches sauvages de moisissures ont été isolées sur milieu Potato Dextrose Agar (PDA) et identifiées. Ces champignons filamenteux sont répartis comme suit : Aspergillus section Nigri (52%) ; Aspergillus verts (13%), Penicillium (10%), Mucor (16%), Fusarium (4%), autre (5%). Les Aspergillus section Nigri qui comptent le complexe Aspergillus niger agreggate et Aspergillus carbonarius représentent un peu plus de la moitié de la population fongique soit 52%, soit 30% en 2008 et 70% en 2009, de la flore fongique totale. Ce groupe a fait l’objet d’une caractérisation morphologique. L’étude du potentiel mycotoxinogène des Aspergillus section Nigri isolées du café robusta a démontré qu’en plus de l’OTA, certaines souches d’Aspergillus Nigri produiraient de l’aflatoxine. Cependant l’espèce Aspergillus carbonarius reste la plus ochratoxinogène (0,6 µg et 15µg d’OTA/g de milieu gélosé). En plus des moisissures 44 souches de bactéries lactiques (LAB) ont été isolées à partir de la pulpe fraîche de café. Les caractères morphologiques, biochimiques et culturaux ont été étudiés. L’identification moléculaire des bactéries a permis de les classer dans le groupe de Lactobacillus plantarum sp. Après un criblage orienté, deux souches de LAB avec un effet important d’inhibition de croissance des moisissures mycotoxinogènes ont été sélectionnées. Les deux souches de Lactobacillus plantarum ont démontré une activité antifongique contre les souches d’Aspergillus carbonarius hautement ochratoxinogènes. Par conséquent la prévention de la mycotoxinogenèse sur café robusta, pourrait passer par l’inhibition de la croissance de certaines moisissures ochratoxinogènes. Les résultats acquis au cours de ce travail de thèse serviront de base afin de poursuivre cette étude d’une part avec des essais in situ pour tester l’efficacité des LAB sélectionnées et d’autre part, rechercher les biomolécules actives contre la germination des spores contaminants naturels post récolte en particulier des cerises de café en Côte d’Ivoire et des fruits et légumes en général. / One of the objectives of this thesis was to describe the significant contamination of robusta coffee beans (Coffea canephora) by moulds during the post-harvest processing of coffee cherries in the dry process. The sampling strategy was to take samples for two consecutive years (2008 and 2009) from different areas of coffee production in Ivory Coast and on the other hand, from the same area but from coffee producers using different methods of drying of coffee beans. From 31 samples, 218 wild strains of fungi were isolated on Potato Dextrose Agar (PDA) media and identified. These filamentous fungi were as follows: black Aspergilli (52%); green Aspergilli (13%), Penicillium (10%), Mucor (16%), Fusarium (4%) and others (5%). The black Aspergilli were found to include Aspergillus niger and Aspergillus carbonarius representing 52% of the fungal population, with a proportion of 30% in 2008 and 70% in 2009 of the total fungal flora. This group was selected to study more about their mycotoxin production. Most strains grown on media and at specific incubation conditions, were capable of producing one or more kinds of mycotoxins. Analysis of mycotoxins from fungi isolated from less than a hundred robusta coffee showed that ochratoxin A (OTA) was not the only mycotoxin that may contaminate the robusta coffee in Ivory Coast. Indeed, several strains belonging to the species Aspergillus Nigri group had shown their ability to produce not only ochratoxin A but also aflatoxin. However, the species A. carbonarius remains as the most ochratoxigenic strain but it does not produce aflatoxin.In parallel to the isolation of fungi, 44 strains of lactic acid bacteria (LAB) were also isolated from fresh coffee cherries, harvested in Ivory Coast in 2009. The morphological, biochemical and growth characteristics were studied. Molecular identification of strains ranked them to be in the group of Lactobacillus plantarum sp. After a screening experiment, it was possible to select two strains of LAB with a significant effect of inhibiting fungal growth by producing mycotoxins. The two strains of Lactobacillus plantarum showed antifungal activity against strains of Aspergillus carbonarius which is highly ochratoxigenic. Therefore the prevention of mycotoxigenicity of robusta coffee, could be rised by inhibiting the growth of certain ochratoxigenic fungi. The results achieved in this thesis serve as a basis to continue the study on one hand with field trials to test the effectiveness of selected LAB on the other hand, look for active biomolecules against spore germination of contaminants especially the natural post-harvest coffee beans in Ivory Coast and fruits and vegetables in general.