Résumé
Abstract Biosurfactants have many advantages over synthetic surfactants but have higher production costs. Identifying microorganisms with high production capacities for these molecules and optimizing their growth conditions can reduce cost. The present work aimed to isolate and identify a fungus with high biosurfactant production capacity, optimize its growth conditions in a low cost culture medium, and characterize the chemical structure of the biosurfactant molecule. The fungal strain UFSM-BAS-01 was isolated from soil contaminated with hydrocarbons and identified as Fusarium fujikuroi. To optimize biosurfactant production, a Plackett-Burman design and a central composite rotational design were used. The variables evaluated were pH, incubation period, temperature, agitation and amount of inoculum in a liquid medium containing glucose. The partial structure of the biosurfactant molecule was identified by nuclear magnetic resonance spectrometry. F. fujikuroi reduced surface tension from 72 to 20 mN m−1 under the optimized conditions of pH 5.0, 37 °C and 7 days of incubation with 190 rpm agitation. The partial identification of the structure of the biosurfactant demonstrated the presence of an α,β-trehalose. The present study is the first report of the biosynthesis of this compound by F. fujikuroi, suggesting that the biosurfactant produced belongs to the class of trehalolipids.
Sujets)
Tensioactifs/métabolisme , Tréhalose/métabolisme , Microbiologie industrielle/méthodes , Fusarium/métabolisme , Tensioactifs/composition chimique , Température , Milieux de culture/métabolisme , Fermentation , Fusarium/croissance et développement , Fusarium/composition chimique , Concentration en ions d'hydrogèneRésumé
Abstract Biosurfactants have many advantages over synthetic surfactants but have higher production costs. Identifying microorganisms with high production capacities for these molecules and optimizing their growth conditions can reduce cost. The present work aimed to isolate and identify a fungus with high biosurfactant production capacity, optimize its growth conditions in a low cost culture medium, and characterize the chemical structure of the biosurfactant molecule. The fungal strain UFSM-BAS-01 was isolated from soil contaminated with hydrocarbons and identified as Fusarium fujikuroi. To optimize biosurfactant production, a PlackettBurman design and a central composite rotational design were used. The variables evaluated were pH, incubation period, temperature, agitation and amount of inoculum in a liquid medium containing glucose. The partial structure of the biosurfactant molecule was identified by nuclear magnetic resonance spectrometry. F. fujikuroi reduced surface tension from 72 to 20 mN m1 under the optimized conditions of pH 5.0, 37 °C and 7 days of incubation with 190 rpm agitation. The partial identification of the structure of the biosurfactant demonstrated the presence of an ,-trehalose. The present study is the first report of the biosynthesis of this compound by F. fujikuroi, suggesting that the biosurfactant produced belongs to the class of trehalolipids.
Résumé
Abstract Production of a bioherbicide for biological control of weeds requires a series of steps, from selection of a suitable microbial strain to final formulation. Thus, this study aimed to select fungi for production of secondary metabolites with herbicidal activity using biological resources of the Brazilian Pampa biome. Phytopathogenic fungi were isolated from infected tissues of weeds in the Pampa biome. A liquid synthetic culture medium was used for production of metabolites. The phytotoxicity of fungal metabolites was assessed via biological tests using the plant Cucumis sativus L., and the most promising strain was identified by molecular analysis. Thirty-nine fungi were isolated, and 28 presented some phytotoxic symptoms against the target plant. Fungus VP51 belonging to the genus Diaporthe showed the most pronounced herbicidal activity. The Brazilian Pampa biome is a potential resource for the development of new and sustainable chemical compounds for modern agriculture.
Sujets)
Produits biologiques/métabolisme , Champignons/métabolisme , Herbicides/métabolisme , Phylogenèse , Brésil , ARN ribosomique 5.8S/génétique , ADN intergénique , Mauvaises herbes/microbiologie , Fermentation , Champignons/isolement et purification , Champignons/classification , Champignons/génétiqueRésumé
In this research it was evaluated the production of biobutanol by
Neste trabalho, foi avaliada a produção de biobutanol por
Résumé
The family Brassicaceae has been very studied due to the pharmacologic properties of the glucosinolates (GLS) and their hydrolysis products, which are associated with the action of an endogenous thioglucosidase myrosinase. Factors such as climate, soil, genotype, seasonal variation, processing, extraction quantification can affect the enzyme activity and stability, leading to increase or decrease the hydrolysis of GLS. Based on this aspect, the main objective of this work is present a review concerning the glucosinolate-myrosinase system, influence of climate and genotype to seasonal variation in the glucosinolate-myrosinase system, effect of thermal and high hydrostatic pressure treatments on the GLS content, as well as, the isolation and quantification of GLS from Brassica.
Résumé
This work is focused on the evaluation of the anti anti-inflammatory activity of fractionated extracts of Salvia officinalis in experimental model of peritonitis. The extract of Salvia officinalis was produced by maceration with ethanol and fractionated by increasing the polarity of the solvents from hexane to methanol in a thin layer chromatographic column with Silica Gel 60 as stationary phase. The acute induced-peritonitis assay was used as model of inflammation, were the fractionated extracts of S. officinalis were administered subcutaneously. After 4h of induction of inflammation the number of total circulating leukocytes was not increased in animals that received the methanol extract. After the induction of inflammation, all animals except those treated with the fraction of ethyl acetate and methanol showed an increased number of circulating neutrophils. The results obtained suggesting the occurrence of inhibition of the total leukocytes recruitment in the circulating blood after the induced-inflammatory process by ethyl acetate and methanolic extracts of S. officinalis in a single dose of 25 μg.kg-1. It was concluded that the extracts of S. officinalis could be used as anti-inflammatory agent.
Résumé
A progeny of Cambona-4, a female maté plant (Ilex paraguariensis) selected by its agronomical characteristics and mild flavor, was evaluated using RAPD markers in order to identify its male parents. Using RAPD markers specifics of each one of the four potential males, the paternity of 84 out of 107 offsprings was confirmed. The majority of the offsprings (83.3%) were ascribed to pollen donor A, while male plants B, C, and D represented 11.9, 4.8, and 0%, respectively. The highly desirable agronomical characteristics and product quality of Cambona-4/pollen donor A offsprings, identified by RAPD markers, lead to the planting of an orchard Cambona-4 and pollinator A to obtain bi-clonal commercial seeds
Uma progênie da matriz feminina de erva-mate (Ilex paraguariensis) denominada Cambona-4, selecionada pelas suas características agronômicas e sabor suave, foi avaliada por marcadores RAPD para a identificação dos respectivos parentais masculinos. Usando-se fragmentos específicos de RAPD de cada um dos quatro polinizadores potenciais, a paternidade de 84 de 107 descendentes foi confirmada. A maioria dos descendentes (83,3%) foi atribuída ao polinizador A, enquanto os polinizadores B, C e D representaram 11,9; 4,8 e 0%, respectivamente. As características agronômicas e de qualidade do produto, oriundas da progênie Cambona-4/polinizador A, identificado pelos marcadores RAPD, direcionaram o plantio de um pomar a partir do cruzamento destas para obtenção de sementes comerciais biclonais.
Sujets)
Ilex paraguariensis , PollinisationRésumé
The use of compressed carbon towards extracting semi-volatile compounds present in maté leaves (Ilex paraguariensis St. Hil.) is due to the growing interest in mate constituents to develop new products in the cosmetic, pharmaceutical and food industries. The objective of this work was to assess the chemical distribution of semi-volatile compounds in 20 native populations of maté collected all over Brazil. The extracts of bulk samples (30 plants) of each population were obtained by the high-pressure carbon dioxide extraction technique, and analyzed by GC/MSD. The quantification of compounds (caffeine, theobromine, phytol, squalene, vitamin E, eicosane, pentatriacontane, and stigmasterol) showed significant variations within the different populations and compounds analyzed, which are not related to geographical origin or macroclimate characteristics. The results pointed out to the importance of genetic and local environmental factors on the chemical composition of this species.
A extração empregando dióxido de carbono a altas pressões em erva-mate (Ilex paraguariensis St. Hil.), tem sido justificada pelo crescente interesse desta matriz vegetal ou de parte de seus constituintes na formulação de novos produtos, tais como cosméticos e medicamentos, entre outros. Neste contexto, o objetivo do presente trabalho é avaliar a distribuição química de compostos semi-voláteis em 20 populações de erva-mate coletadas em toda área de distribuição desta espécie no Brasil. 30 plantas foram selecionadas para produzir a amostra de cada população. Os extratos de cada amostra foram obtidos por extração com dióxido de carbono a alta pressão e, posteriormente, foram analisados por CG/EM. A quantificação de alguns compostos semi-voláteis presentes nos extratos (cafeína, teobromina, fitol, esqualeno, vitamina E, eicosano, pentatriacontano e stigmasterol), apresentaram variações significativas entre as concentrações dos diferentes compostos analisados nas diferentes populações, os quais não estão relacionados com origem geográfica ou com características de macroclima. Os resultados apontam para a importância dos fatores genéticos e/ou fatores de microclima sobre a composição química desta espécie.