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Utilização de subprodutos da indústria de biodiesel na alimentação de ruminantes

ABDALLA, Adibe Luiz; SILVA FILHO, José Cleto da; GODOI, Antonio Roberto de; CARMO, Carolina de Almeida; EDUARDO, José Luiz de Paula
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
46.49%
Com a introdução de óleo vegetal na cadeia produtiva do biocombustível no Brasil, é esperado o aumento da demanda por plantas oleaginosas e oferta de fibras vegetais resultantes da extração do óleo. Considerando a alimentação animal como elo entre a produção de biodiesel e a pecuária, propomos o estudo da utilização de subprodutos destes empreendimentos na alimentação visando aumentar a produtividade e diminuir a emissão de gases de efeito estufa pelos animais, gerando créditos de carbono e atendendo ao interesse da iniciativa privada. A técnica de produção de gases in vitro tem sido utilizada no LANA-CENA/USP com a finalidade de estudar o efeito de alimentos que possuem metabólitos secundários bioativos, na fermentação ruminal e degradabilidade da matéria orgânica (MOVD), bem como, no estudo da produção de metano. Resultados recentes mostraram que a substituição total do farelo de soja por tortas de algodão, dendê, mamona e pinhão manso proporcionou menor produção total de gases; e que a produção de metano foi significativamente afetada pela inclusão das tortas, sendo que o farelo de soja apresentou produção de metano de 15,3 mL/g MOVD. Diversos trabalhos mostram que as tortas e farelos apresentam características nutricionais adequadas para inclusão na dieta de ruminantes...

Use of Experimental Design for the Optimization of the Production of New Secondary Metabolites by Two Penicillium Species

PIMENTA, Eli F.; VITA-MARQUES, Aline M.; TININIS, Aristeu; SELEGHIM, Mirna H. R.; SETTE, Lara D.; VELOSO, Katyuscya; FERREIRA, Antonio G.; WILLIAMS, David E.; PATRICK, Brian O.; DALISAY, Doralyn S.; ANDERSEN, Raymond J.; BERLINCK, Roberto G. S.
Fonte: AMER CHEMICAL SOC Publicador: AMER CHEMICAL SOC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.39%
A fractional factorial design approach has been used to enhance secondary metabolite production by two Penicillium strains. The method was initially used to improve the production of bioactive extracts as a whole and subsequently to optimize the production of particular bioactive metabolites. Enhancements of over 500% in secondary metabolite production were observed for both P. oxalicum and P. citrinum. Two new alkaloids, citrinalins A (5) and B (6), were isolated and identified from P. citrinum cultures optimized for production of minor metabolites.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); FAPESP as BIOTA/BIOprospecTA[05/60175-2]; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); FAPESP as BIOTA/BIOprospecTA[06/61693-0]

Identificação, produção de antimicrobianos e complexos enzimáticos de isolados de actinomicetos; Identification, production bioactive metabolites and complex enzymatic isolated of actinomycetes

Rodrigues, Katiane
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
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46.52%
A compostagem é um processo biológico natural de degradação da matéria orgânica realizado espontaneamente no ambiente pelos microrganismos. Entre estes microrganismos os actinomicetos são bactérias Gram-positivas com grandes concentrações de G+C em seu DNA. Os actinomicetos são responsáveis pela decomposição de resíduos complexos em leira de compostagem. Eles são bastante conhecidos devido a sua capacidade de produzir inúmeros compostos bioquimicamente ativos como: antibióticos, vitaminas e enzimas. O objetivo desse trabalho foi isolar e identificar actinomicetos de processo de compostagem e avaliar a sua capacidade de sintetizar enzimas extracelulares e metabólitos ativos contra bactérias e leveduras patogênicas. Foram realizadas 10 coletas em uma leira de compostagem composta de resíduos domésticos. Os isolados foram identificados através de microbiologia clássica utilizando análise morfológica das estruturas reprodutivas e provas bioquímicas. A atividade enzimática foi avaliada utilizando amido, carboximetilcelulose, tween 80, caseína, pectina, óleo de oliva e gelatina como substrato. Foram isolados 195 actinomicetos com predomínio dos gêneros Streptomyces sp. (66,1%) e Nocardia sp. (25,1%). Na avaliação da atividade bioativa contra bactérias e leveduras patogênicas 47...

Bioactive Metabolites Produced by Penicillium sp.1 and sp.2, Two Endophytes Associated with Alibertia macrophylla (Rubiaceae)

Oliveira, Camila M.; Silva, Geraldo H.; Regasini, Luis O.; Zanardi, Lisineia M.; Evangelista, Alana H.; Young, Maria C. M.; Bolzani, Vanderlan da Silva; Araujo, Angela R.
Fonte: Verlag Z Naturforsch Publicador: Verlag Z Naturforsch
Tipo: Artigo de Revista Científica Formato: 824-830
ENG
Relevância na Pesquisa
46.34%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Processo FAPESP: 03/02176-7; In the course of our continuous search for bioactive metabolites from endophytic fungi living in plants from the Brazilian flora, leaves of Alibertia macrophylla (Rubiaceae) were submitted to isolation of endophytes, and two species of Penicillium were isolated. The acetonitrile fraction obtained in corn from a culture of Penicillium sp.1 afforded orcinol (1). on the other hand, Penicillium sp.1 cultivated in potato-dextrose-broth furnished two different compounds, cyclo-(L-Pro-L-Val) (2) and uracil (3). The chromatographic fractionation of the acetonitrile fraction obtained from Penicillium sp.2 led to three dihydroisocoumarins, 4-hydroxymellein (4), 8-methoxymellein (5) and 5-hydroxymellein (6). Compounds 5 and 6 were obtained from the Penicillium genus for the first time. Additionally, metabolites 1-6 were evaluated for their antifungal and acetylcholinesterase (AChE) inhibitory activities. The most active compounds 1. and 4 exhibited detection limits of 5.00 and 10.0 mu g against Cladosporium. cladosporioides and C. sphaerospermum, respectively. Compound 2 showed a detection limit of 10.0 mu g...

New bioactive metabolites produced by Phomopsis cassiae, an endophytic fungus in Cassia spectabilis

Silva, Geraldo H.; Araújo, Ângela R.; Telesa, Helder L.; Trevisana, Henrique C.; Bolzani, Vanderlan da Silva; Young, Maria C. M.; Pfenning, Ludwig H.; Eberlind, Marcos N.; Haddad, Renato; Costa-Netoe, Claudio M.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1463-1466
ENG
Relevância na Pesquisa
46.16%
Two new metabolites, ethyl 2,4-dihydroxy-5,6-dimethylbenzoate (1) and phomopsilactone (2) were isolated from Phomopsis cassiae, an endophytic fungus in Cassia spectabilis. Their structures were elucidated by 1D and 2D NMR, MS and IR spectral data. Compounds 1 and 2 displayed strong antifungal activity against the phytopatogenic fungi Cladosporium cladosporioides and C. sphaerospermum, as well as cytotoxicity against human cervical tumor cell line (HeLa), in in vitro assays. ©2005 Sociedade Brasileira de Química.

Involviment of cannabinoids CB1, CB2 recepotrs and KAPT channel in the anti-hiperalgesic effect mediated by dipyrone and its bioactives metabolites : Envolvimento dos receptores canabinóides CB-1 e CB-2 e canais KATP do tecido periférico na analgesia mediada pela dipirona e seus metabólitos bioativos; Envolvimento dos receptores canabinóides CB-1 e CB-2 e canais KATP do tecido periférico na analgesia mediada pela dipirona e seus metabólitos bioativos

Gilson Goncalves dos Santos
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 18/12/2014 PT
Relevância na Pesquisa
46.16%
A dipirona (metamizol) é um pró-fármaco analgésico utilizado no controle da dor moderada, sendo metabolizada em dois metabolitos bioativos: 4-metil-aminoantipirina (4-MAA) e 4-aminoantipirina (4-AA). O objetivo deste estudo foi investigar a participação de receptores canabinóides periféricos, CB1, CB2 e canais de KATP sobre o efeito anti-hiperalgésico da dipirona, 4-MAA ou 4- AA. Para indução de hiperalgesia, PGE2 (100 ng/pata ) foi administrada localmente na pata traseira de ratos Wistar machos, e o limiar hiperalgésico mecânico foi quantificado por Von- Frey eletrônico, antes e três horas após a injeção. Dipirona, 4-MAA ou 4-AA foram administrados 30 minutos antes do Von Frey. Os antagonistas seletivos do receptor CB1 (AM251), CB2 (AM630) e glibenclamida, um bloqueador KATP (80 ug) ou ODQ um inibidor de cGMP (32 ?g) foram administrados 30 minutos antes da Dipirona, 4-MAA ou 4 -AA. O ODN-antisense para reduzir a expressão do receptor CB1 (30 ?g) foi administrado por via intratecal, uma vez por dia durante quatro dias consecutivos. A hiperalgesia mecânica induzida pela PGE2 foi reduzida pela dipirona, 4-MAA, e 4-AA de maneira dose-dependente. AM251 ou ODN-antisense contra o receptor neuronal CB1, mas não AM630...

Antimicrobial activity of extracellular metabolites from antagonistic bacteria isolated from potato (Solanum phureja) crops

Granada García,Sinar David; Rueda Lorza,Antoni; Peláez,Carlos Alberto
Fonte: Grupo Paulista de Fitopatologia Publicador: Grupo Paulista de Fitopatologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2014 EN
Relevância na Pesquisa
46.16%
Microorganisms for biological control are capable of producing active compounds that inhibit the development of phytopathogens, constituting a promising tool toob tain active principles that could replace synthetic pesticides. This study evaluatedtheability of severalpotentialbiocontrol microorganismsto produce active extracellular metabolites. In vitro antagonistic capability of 50 bacterial isolates from rhizospheric soils of "criolla" potato (Solanum phureja) was tested through dual culture in this plant with different plant pathogenic fungi and bacteria. Isolates that showed significantly higher antagonistic activity were fermented in liquid media and crude extracts from the supernatants had their biological activities assessed by optical density techniques. Inhibitory effecton tested pathogens was observed for concentrations between 0.5% and 1% of crude extracts. There was a correlation between the antimicrobial activity of extracts and the use of nutrient-rich media in bacteria fermentation. Using a bioguided method, a peptidic compound, active against Fusarium oxysporum, was obtained from the 7ANT04 strain (Pyrobaculum sp.). Analysis by nuclear magnetic resonance and liquid chromatography coupled to mass detector evidenced an 11-amino acid compound. Bioinformatic software using raw mass data confirmed the presence of a cyclic peptide conformed by 11 mostly non-standard amino acids.

New bioactive metabolites produced by Phomopsis cassiae, an endophytic fungus in Cassia spectabilis

Silva,Geraldo H.; Teles,Helder L.; Trevisan,Henrique C.; Bolzani,Vanderlan da S.; Young,Maria C. M.; Pfenning,Ludwig H.; Eberlin,Marcos N.; Haddad,Renato; Costa-Neto,Claudio M.; Araújo,Ângela R.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2005 EN
Relevância na Pesquisa
46.16%
Two new metabolites, ethyl 2,4-dihydroxy-5,6-dimethylbenzoate (1) and phomopsilactone (2) were isolated from Phomopsis cassiae, an endophytic fungus in Cassia spectabilis. Their structures were elucidated by 1D and 2D NMR, MS and IR spectral data. Compounds 1 and 2 displayed strong antifungal activity against the phytopatogenic fungi Cladosporium cladosporioides and C. sphaerospermum, as well as cytotoxicity against human cervical tumor cell line (HeLa), in in vitro assays.

Modulation of antimicrobial metabolites production by the fungus Aspergillus parasiticus

Bracarense,Adriana A.P.; Takahashi,Jacqueline A.
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
Relevância na Pesquisa
46.29%
Biosynthesis of active secondary metabolites by fungi occurs as a specific response to the different growing environments. Changes in this environment alter the chemical and biological profiles leading to metabolites diversification and consequently to novel pharmacological applications. In this work, it was studied the influence of three parameters (fermentation length, medium composition and aeration) in the biosyntheses of antimicrobial metabolites by the fungus Aspergillus parasiticus in 10 distinct fermentation periods. Metabolism modulation in two culturing media, CYA and YES was evaluated by a 2² full factorial planning (ANOVA) and on a 2³ factorial planning, role of aeration, medium composition and carbohydrate concentration were also evaluated. In overall, 120 different extracts were prepared, their HPLC profiles were obtained and the antimicrobial activity against A. flavus, C. albicans, E. coli and S. aureus of all extracts was evaluated by microdilution bioassay. Yield of kojic acid, a fine chemical produced by the fungus A. parasiticus was determined in all extracts. Statistical analyses pointed thirteen conditions able to modulate the production of bioactive metabolites by A. parasiticus. Effect of carbon source in metabolites diversification was significant as shown by the changes in the HPLC profiles of the extracts. Most of the extracts presented inhibition rates higher than that of kojic acid as for the extract obtained after 6 days of fermentation in YES medium under stirring. Kojic acid was not the only metabolite responsible for the activity since some highly active extracts showed to possess low amounts of this compound...

Formation of Methylated and Phosphorylated Metabolites During the Fermentation Process of Verdamicin

Lee, B. K.; Condon, R. G.; Wagman, G. H.; Weinstein, M. J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1976 EN
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36.63%
In an attempt to understand the biosynthetic processes leading to the formation of verdamicin (end product), we have examined the patterns of the formation of methylated and phosphorylated metabolites, which resulted from either the addition of l-[methyl-14C]methionine or [32P]KH2PO4 to the fermentation. Incorporation of label from l-[methyl-14C]methionine into the bioactive sisomicin, verdamicin, and the chromatographically polar components increased with the progression of time. Two methylated bioinactive metabolites were found in the culture broth after removal of the methylated bioactive metabolites. In contrast to the bioactive metabolites, incorporation of the methyl-14C label into the two methylated bioinactive metabolites decreased with the progression of time. A phosphorylated bioinactive metabolite (nonmethylated) was also found in the culture broth, fermented in the presence of [32P]KH2PO4. The role of the phosphorylated metabolite in the biosynthesis of the bioactive metabolites cannot yet be explained.

Low Water Activity Induces the Production of Bioactive Metabolites in Halophilic and Halotolerant Fungi

Sepcic, Kristina; Zalar, Polona; Gunde-Cimerman, Nina
Fonte: Molecular Diversity Preservation International Publicador: Molecular Diversity Preservation International
Tipo: Artigo de Revista Científica
Publicado em 27/12/2010 EN
Relevância na Pesquisa
46.44%
The aim of the present study was to investigate indigenous fungal communities isolated from extreme environments (hypersaline waters of solar salterns and subglacial ice), for the production of metabolic compounds with selected biological activities: hemolysis, antibacterial, and acetylcholinesterase inhibition. In their natural habitats, the selected fungi are exposed to environmental extremes, and therefore the production of bioactive metabolites was tested under both standard growth conditions for mesophilic microorganisms, and at high NaCl and sugar concentrations and low growth temperatures. The results indicate that selected halotolerant and halophilic species synthesize specific bioactive metabolites under conditions that represent stress for non-adapted species. Furthermore, adaptation at the level of the chemical nature of the solute lowering the water activity of the medium was observed. Increased salt concentrations resulted in higher hemolytic activity, particularly within species dominating the salterns. The appearance of antibacterial potential under stress conditions was seen in the similar pattern of fungal species as for hemolysis. The active extracts exclusively affected the growth of the Gram-positive bacterium tested...

Search for Hydrophilic Marine Fungal Metabolites: A Rational Approach for Their Production and Extraction in a Bioactivity Screening Context

Le Ker, Carine; Petit, Karina-Ethel; Biard, Jean-François; Fleurence, Joël
Fonte: Molecular Diversity Preservation International Publicador: Molecular Diversity Preservation International
Tipo: Artigo de Revista Científica
Publicado em 10/01/2011 EN
Relevância na Pesquisa
36.49%
In the search for bioactive natural products, our lab screens hydrophobic extracts from marine fungal strains. While hydrophilic active substances were recently identified from marine macro-organisms, there was a lack of reported metabolites in the marine fungi area. As such, we decided to develop a general procedure for screening of hydrophobic metabolites. The aim of this study was to compare different processes of fermentation and extraction, using six representative marine fungal strains, in order to define the optimized method for production. The parameters studied were (a) which polar solvent to select, (b) which fermentation method to choose between solid and liquid cultures, (c) which raw material, the mycelium or its medium, to extract and (d) which extraction process to apply. The biochemical analysis and biological evaluations of obtained extracts led to the conclusion that the culture of marine fungi by agar surface fermentation followed by the separate extraction of the mycelium and its medium by a cryo-crushing and an enzymatic digestion with agarase, respectively, was the best procedure when screening for hydrophilic bioactive metabolites. During this development, several bioactivities were detected, confirming the potential of hydrophilic crude extracts in the search for bioactive natural products.

Optimization of Culturing Conditions for Improved Production of Bioactive Metabolites by Pseudonocardia sp. VUK-10

Usha Kiranmayi, Mangamuri; Sudhakar, Poda; Sreenivasulu, Kamma; Vijayalakshmi, Muvva
Fonte: The Korean Society of Mycology Publicador: The Korean Society of Mycology
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.65%
The purpose of the present study was to investigate the influence of cultural and environmental parameters affecting the growth and bioactive metabolite production of the rare strain VUK-10 of actinomycete Pseudonocardia, which exhibits a broad spectrum of in vitro antimicrobial activity against bacteria and fungi. Production of bioactive metabolites by the strain was high the in modified yeast extract-malt extract-dextrose (ISP-2) broth, as compared to other tested media. Glucose (1%) and tryptone (0.25%) were found to be the most suitable carbon and nitrogen sources, respectively, for optimum production of growth and bioactive metabolites. Maximum production of bioactive metabolites was found in the culture medium with initial pH 7 incubated with the strain for four days at 30℃, under shaking conditions. This is the first report on the optimization of bioactive metabolites by Pseudonocardia sp. VUK-10.

A Preliminary Study of the Algicidal Mechanism of Bioactive Metabolites of Brevibacillus laterosporus on Oscillatoria in Prawn Ponds

Jia, Wen; Huang, Xianghu; Li, Changling
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 09/03/2014 EN
Relevância na Pesquisa
46.49%
The algae, Oscillatoria, is commonly found in prawn ponds and can lead to reduced productivity. We examined metabolites of the bacteria Brevibacillus laterosporus for algicidal qualities. To determine the possible algicidal mechanisms of these bioactive metabolites, different amounts of sterile filtrate of bacterial suspensions were added to cultures containing Oscillatoria. The dry weight, the concentrations of chlorophyll-a (chl-a), phycobiliprotein (PC, phycocyanin; APC, allophycocyanin; PE, phycoerythrin), and MDA (malondialdehyde) and the activities of SOD (superoxide dismutase), POD (peroxidase), and CAT (catalase) of algae were measured during the algicidal application. The results showed that lower concentrations of the sterile filtrate (addition ≤ 4 mL) accelerated the growth rate of Oscillatoria, but significant inhibition and lysis were observed with higher concentrations (addition ≥ 8 mL). In two trials (the additions were 8 mL and 10 mL, respectively), the algal dry weights were reduced by 26.02% and 45.30%, and the chl-a concentrations were decreased by 46.88% and 63.73%, respectively, after seven days. During the algicidal treatment, the concentrations of PC, APC, PE, and MDA and the activities of SOD, POD...

Major bioactive metabolites from marine fungi: A Review

Hasan, Saba; Ansari, Mohammad Israil; Ahmad, Anis; Mishra, Maitreyi
Fonte: Biomedical Informatics Publicador: Biomedical Informatics
Tipo: Artigo de Revista Científica
Publicado em 30/04/2015 EN
Relevância na Pesquisa
46.49%
Biologists and chemists of the world have been attracted towards marine natural products for the last five decades. Approximately 16,000 marine natural products have been isolated from marine organisms which have been reported in approximately 6,800 publications, proving marine microorganisms to be a invaluable source for the production of novel antibiotic, anti tumor, and anti inflammatory agents. The marine fungi particularly those associated with marine alga, sponge, invertebrates, and sediments appear to be a rich source for secondary metabolites, possessing Antibiotic, antiviral, antifungal and antiyeast activities. Besides, a few growth stimulant properties which may be useful in studies on wound healing, carcinogenic properties, and in the study of cancers are reported. Recent investigations on marine filamentous fungi looking for biologically active secondary metabolites indicate the tremendous potential of them as a source of new medicines. The present study reviews about some important bioactive metabolites reported from marine fungal strains which are anti bacterial, anti tumour and anti inflammatory in action. It highlights the chemistry and biological activity of the major bioactive alkaloids, polyketides, terpenoids, isoprenoid and non-isoprenoid compounds...

Effects of different culture conditions on biological potential and metabolites production in threePenicilliumisolates

Reis, Filipa S.; Ćirić, Ana; Stojković, Dejan; Barros, Lillian; Ljaljević-Grbić, Milica; Soković, Marina; Ferreira, Isabel C.F.R.
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.43%
The genus Penicillium is well known for its importance in drug and food production. Certain species are produced on an industrial scale for the production of antibiotics (e.g. penicillin) or for insertion in food (e.g. cheese). In the present work, three Penicillium species, part of the natural mycobiota growing on various food products were selected– P. ochrochloron, P. funiculosum and P. verrucosum var. cyclopium. The objective of our study was to value these species from the point of view of production of bioactive metabolites. The species were obtained after inoculation and growth in Czapek and Malt media. Both mycelia and culture media were analyzed to monitor the production of different metabolites by each fungus and their release to the culture medium. The concentrations of sugars, organic acids, phenolic acids and tocopherols, were determined. Antioxidant activity of the phenolic extracts was evaluated, as also the antimicrobial activity of phenolic acids, organic acids and tocopherols extracts. Rhamnose, xylose, fructose and trehalose were found in all the mycelia and culture media; the prevailing organic acids were oxalic and fumaric acids, and protocatechuic and p-hydroxybenzoic acids were the most common phenolic acids; γ-tocopherol was the most abundant vitamin E isoform. Generally...

Aislamiento y determinación estructural de metabolitos bioactivos con potencial aplicación en apicultura y agricultura obtenidos a partir de cultivos de hongos; Isolation and structural determination of bioactive metabolites with potential use in apiculture and agriculture from fungal cultures

Gallardo, Gabriela Laura
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2009 SPA
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46.21%
En esta tesis se describe el aislamiento, bioguiado a través de ensayos de actividad antifúngica y/o antibacteriana, y la elucidación estructural de los metabolitos presentes en los cultivos de hongos provenientes de diversas fuentes naturales. Las especies analizadas Alternaria brassicicola, A. raphani, Aspergillus restrictus, Trichoderma koniigii y Ascosphaera apis fueron aisladas de polen de colmenas ubicadas en el apiario del INTA (Instituto Nacional de Tecnología Agropecuaria) de la ciudad de Balcarce, Buenos Aires, Argentina. De Alternaria brassicicola y A. raphani se aislaron los compuestos 1-4, siendo el ácido tenuazónico, compuesto 2, el responsable de la actividad antibacteriana frente a la bacteria P. larvae, patógena de las larvas de las abejas melíferas. El compuesto 1, ácido D-allo-tenuazónico, es aislado por primera vez como producto natural. De Aspergillus restrictus se aisló el compuesto 3, conocido como pseurotina A3. Del hongo entomopatógeno de las larvas de las abejas melíferas, Ascosphaera apis, se aislaron los compuestos 6-8, siendo 6 y 8 monoterpenos de estructura química no informada previamente. Los compuestos 6 y 8 mostraron actividades antibióticas, antifúngicas y antioxidantes moderadas...

Bioactive metabolites from the Andean flora. Antituberculosis activity of natural and semisynthetic azorellane and mulinane diterpenoids

González Collado, Isidro; Escalante Erosa, Fabiola; Yam Puc, Alejandro; Bórquez, Jorge; Said Fernández, Salvador; Ardiles, Alejandro; Peña Rodríguez, Luis Manuel; Becerril Montes, Pola; San Martín, Aurelio; Loyola, Luis Alberto; Molina Salinas, Glor
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artículo de revista
EN
Relevância na Pesquisa
46.34%
Artículo de publicación ISI.; Natural products are recognized as an important source of new and better pharmaceuticals for the treatment of diseases such as tuberculosis. The azorellane and mulinane diterpenoids represent an interesting group of bioactive metabolites produced by Andean plants belonging to the Azorella, Mulinum, Laretia and Bolax genus. Testing of natural and semisynthetic azorellanes and mulinanes against two Mycobacterium tuberculosis strains showed that while most changes in the structure of the natural metabolites result in the loss of antituberculosis activity, methylation of the C-20 carboxyl group improves the biological activity of the corresponding derivatives.; LAL wishes to acknowledge FONDECYT-Chile support for this project (Grant No. 1060339). The evaluation of antituberculosis activity in this collaborative work was supported by Instituto Mexicano del Seguro Social (Project 2008-1908-4). Research was performed under the auspices of the EULADIV Alfa Project, FOMIXYucata ´n Project No. 66262 and Programa de Cooperacio´n Bilateral Mexico-Chile.

Bioprospecção de actinobactérias associadas à esponja marinha Aplysina fulva: isolamento, caracterização e produção de compostos bioativos; Bioprospecting of actinobacteria associated with marine sponge Aplysina fulva: isolation, characterization and production of bioactive compounds

Silva, Fábio Sérgio Paulino da
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 03/11/2015 PT
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36.55%
Este estudo descreve a diversidade de actinobactérias isoladas da esponja marinha Aplysina fulva e o potencial destes microorganismos como produtores de metabólitos bioativos com propriedades fungicidas e herbicidas. Actinobactérias são prolíficas produtoras de compostos farmacologicamente importantes, pois cerca de 70% dos antibióticos naturalmente derivados que estão atualmente em uso clínico são produzidos por estes microorganismos. Entretanto este valor é ainda inexpressivo na indústria agrícola. Agroquímicos sintéticos ainda são dominantes no mercado apesar de estarem menos efetivos contra plantas daninhas e patógenos cada vez mais resistentes. Neste trabalho, um total de 21 actinobactérias foram isoladas com a utilização de meios seletivos. Análises filogenéticas baseadas no sequenciamento parcial do gene que codifica para o rRNA 16S mostrou que estes microorganismos pertencem a oito gêneros do filo Actinobacteria: Kocuria; Citricoccus; Terrabacter; Gordonia; Agrococcus; Tsukamurella; Brevibacterium e Streptomyces. Os extratos de todos os isolados foram testados para verificar a produção de metabólitos secundários com propriedades fungicidas contra os fungos fitopagênicos de importância agrícola: Pythium aphanidermatum; Phytophthora capsici e Magnaporthe grisea. O extrato bruto de 43% dos isolados mostrou atividade fungicida para ao menos um dos patógenos. O perfil químico do extrato dos isolados com bioatividade positiva foram similares mesmo entre gêneros diferentes. Os metabólitos do Streptomyces ASPSP 103 foram mais eficientes devido à forte inibição contra todos os patógenos testados. Portanto este isolado foi selecionado e testado para atividade herbicida por meio de screening que teve início com testes de atividade algicida contra a microalga Selenastrum capricornutum. Acreditamos que actinobactérias associadas a esponjas marinhas desempenham um papel de defesa química contra microalgas que possam obstruir os porócitos asfixiando o animal...

A fast method using a new hydrophilic–lipophilic balanced sorbent in combination with ultra-high performance liquid chromatography for quantification of significant bioactive metabolites in wines

Silva, Catarina L.; Pereira, Jorge; Wouter, Van G.; Giró, Carme; Câmara, José S.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /10/2011 ENG
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This manuscript describes the development and validation of an ultra-fast, efficient, and high throughput analytical method based on ultra-high performance liquid chromatography (UHPLC) equipped with a photodiode array (PDA) detection system, for the simultaneous analysis of fifteen bioactive metabolites: gallic acid, protocatechuic acid, (−)-catechin, gentisic acid, (−)-epicatechin, syringic acid, p-coumaric acid, ferulic acid, m-coumaric acid, rutin, trans-resveratrol, myricetin, quercetin, cinnamic acid and kaempferol, in wines. A 50-mm column packed with 1.7-μm particles operating at elevated pressure (UHPLC strategy) was selected to attain ultra-fast analysis and highly efficient separations. In order to reduce the complexity of wine extract and improve the recovery efficiency, a reverse-phase solid-phase extraction (SPE) procedure using as sorbent a new macroporous copolymer made from a balanced ratio of two monomers, the lipophilic divinylbenzene and the hydrophilic N-vinylpyrrolidone (Oasis™ HLB), was performed prior to UHPLC–PDA analysis. The calibration curves of bioactive metabolites showed good linearity within the established range. Limits of detection (LOD) and quantification (LOQ) ranged from 0.006 μg mL−1 to 0.58 μg mL−1...