Production and characterization of β-glucosidase from Gongronella butleri by solid-state fermentation

Among the enzymes of the cellulolytic complex, β-glucosidases are noteworthy due to the possibility of their application in different industrial processes, such as production of biofuels, winemaking, and development of functional foods. This study aimed to evaluate the production and characterization of β-glucosidase from the filamentous fungus Gongronella butleri, recently isolated from Cerrado soil and cultivated in agro-industrial residue substrates. The highest production of β-glucosidase, about 215.4 U/g of dry substrate (or 21.5 U/mL), was obtained by cultivation of the microorganism on wheat bran with 55% of the initial moisture, for 96 h at 30°C. This β-glucosidase showed higher catalytic activity at pH 4.5, and a temperature of 65°C. The original enzymatic activity was recovered in a pH range of 3.0-7.5 after 24 h of incubation. The enzyme retained 80% of its catalytic activity when incubated for 1 h at 50°C. The enzyme was strongly inhibited by glucose, an effect that was completely reversed by increasing substrate concentration in the reaction mixture, which is typical for competitive inhibition. High catalytic activity was observed in solutions containing up to 20% ethanol, allowing the application of this enzyme in processes with high alcohol concentrations (for example beverages and biofuels). The significant production of β-glucosidase by the selected strain, along with these enzyme characteristics, highlights the biotechnological potential of the fungus G. butleri.Key words: Microbial enzyme, biofuels, agro-industrial residues, cellulases, hemicellulases

Production of chitosan based films enriched with oregano essential oil for increased antibacterial activity

During the last years, there has been an increasing interest in developing bio-based active films to improve food safety, extend food shelf life and reduce the use of chemical preservatives. Chitosan, a deacetylated derivative of chitin, is a linear polysaccharide consisting of -(1 4) glucosamine and N-acetylglucosamine residues with potential to be used as a food packaging/coating material. This biopolymer can be used in a wide range of applications in the food industry due to several interesting properties such as its biodegradability, biocompatibility, non-toxicity, antimicrobial activity and versatile physical properties such as its film-forming capacity. Recently, different strategies have been explored to improve its natural properties for the development of food packaging/coating materials with enhanced antimicrobial activity. In particular, the incorporation in chitosan films of essential oils (EO) with acknowledged antibacterial properties, as an alternative of synthetic preservatives, is a matter of great interest since they are generally perceived by consumers as being “natural” food additives. Thus, the objective of this work was the production of chitosan films enriched with oregano EO to further improve the natural antimicrobial properties of chitosan. The obtained films which were then evaluated for its antibacterial activity

Avaliação das condições microbiológicas do ar ambiente em unidades de restauração. Resultados preliminares

O presente estudo pretende avaliar a qualidade microbiológica do ar ambiente de unidades de restauração e verificar se as condições existentes obedecem aos valores recomendados pela American Public Health Association (APHA). Foram avaliados os microrganismos mesófilos aeróbios e bolores/leveduras de três unidades de restauração (A, B e C), através da técnica de sedimentação simples, nos seguintes locais: cozinha, sala de refeições e exterior do edifício. Os resultados mostram que a qualidade microbiológica dos ambientes das cozinhas é insatisfatória, apresentando contagens de microrganismos superiores ao valor recomendado (até 30 UFC/cm2/semana). As maiores contagens foram obtidas no período Primavera/Verão. Pelo contrário, valores abaixo do recomendado foram obtidos, na maioria das vezes, nas salas de refeições

Production of chitosan based films enriched with oregano essential oil for increased antibacterial activity

During the last years, there has been an increasing interest in developing bio-based active films to improve food safety, extend food shelf life and reduce the use of chemical preservatives [1]. Chitosan, a deacetylated derivative of chitin, is a linear polysaccharide consisting of β-(I⇒t4) glucosarnine and N-acetylglucosamine residues with potential to be used as a food packaging/coating material. This biopolymer can be used in a wide range of applications in the food industry due to several interesting properties such as its biodegradability, biocompatibility, non-toxicity, antimicrobial activity and versatile physical properties such as its film-forming capacity [I]. Recently, different strategies have been explored to improve its natural properties for the development of food packaging/coating materials with enhanced antimicrobial activity. In particular, the incorporation of essential oils (EO) with recognized antibacterial properties, as an alternative of synthetic preservatives, is a matter of great interest since they are generally perceived by consumers as being "natural" food additives

Effect of protective coatings on the water absorption and mechanical properties of 3D printed PLA

This work aims to study the influence of protective coatings on the water absorption and mechanical properties of 3D printed polyꖖlactic acid (PLA) parts. The PLA parts were fabricated with different levels of the 3D printing process parameters, aiming to define samples with distinct strength and ductility/toughness characteristics. Water absorption tests following the standard ASTM D570�98 were performed on uncoated and coated PLA specimens. The effectiveness of two protective coatings based on acrylic and polyurethane varnish on reducing water absorption was evaluated. Both protective coatings have shown being effective on preventing water absorption by the PLA, with polyurethane presenting the best performance reducing water absorption by 38%. Tensile tests were carried out to determine the ultimate tensile strength, elastic modulus, yield tensile strength, fracture strain and toughness of specimens, before and after the application of protective coatings. The polyurethane protective coating also benefits the tensile properties of PLA parts, increasing the strength and ductility/toughness characteristics of specimens up to 24%

Graded Poisson-Sigma Models and Dilaton-Deformed 2D Supergravity Algebra

Fermionic extensions of generic 2d gravity theories obtained from the graded Poisson-Sigma model (gPSM) approach show a large degree of ambiguity. In addition, obstructions may reduce the allowed range of fields as given by the bosonic theory, or even prohibit any extension in certain cases. In our present work we relate the finite W-algebras inherent in the gPSM algebra of constraints to algebras which can be interpreted as supergravities in the usual sense (Neuveu-Schwarz or Ramond algebras resp.), deformed by the presence of the dilaton field. With very straightforward and natural assumptions on them --like demanding rigid supersymmetry in a certain flat limit, or linking the anti-commutator of certain fermionic charges to the Hamiltonian constraint-- in the ``genuine'' supergravity obtained in this way the ambiguities disappear, as well as the obstructions referred to above. Thus all especially interesting bosonic models (spherically reduced gravity, the Jackiw-Teitelboim model etc.)\ under these conditions possess a unique fermionic extension and are free from new singularities. The superspace supergravity model of Howe is found as a special case of this supergravity action. For this class of models the relation between bosonic potential and prepotential does not introduce obstructions as well.Comment: 22 pages, LaTeX, JHEP class. v3: Final version, to appear in JHE

A 46,XX testicular disorder of sex development caused by a Wilms’ tumour Factorâ 1 (WT1) pathogenic variant

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146930/1/cge13459_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146930/2/cge13459.pd

Equine infectious anemia : prevalence in working equids of livestock herds, in Minas Gerais, Brazil

Estimaram-se, no estado de Minas Gerais, a prevalência e a distribuição espacial da anemia infecciosa eqüina (AIE) em propriedades com eqüídeos de serviço. As amostras de sangue, de 6540 eqüídeos de 1940 rebanhos foram coletadas no período de setembro de 2003 a março de 2004, nos 853 municípios do estado. Utilizaram-se dois testes de laboratório em seqüência: ELISA, usando-se antígeno recombinante gp90, e imunodifusão em gel de ágar (IDGA). As prevalências foram de 5,3% [IC=4,3 a 6,3%] para rebanhos e de 3,1% [IC=2,2 a 3,9%] para animais. O estado de Minas Gerais foi considerado área endêmica para AIE. As mais altas prevalências para rebanhos e para animais foram encontradas na região Norte/Noroeste, seguida pela região Vale do Mucuri/Jequitinhonha. ___________________________________________________________________________________________________________ ABSTRACTThe prevalence and spatial distribution of equine infectious anemia (EIA) were estimated in livestock herds where equids were used as draft power and for transportation in the State of Minas Gerais, Brazil. Serum samples were collected from September/2003 to March/2004 in 853 municipalities of the state. The sample comprised 6,540 equids from 1,940 herds. Two laboratorial tests were performed in sequence: ELISA using a recombinant gp90 protein, following by the AGID. The prevalence in the herds was estimated in 5.3% [CI = 4.3 to 6.3%], and 3.1% [CI = 2.2 to 3.9%] of the animals tested were positive. Minas Gerais was considered an endemic region for EIA. The highest prevalence for herds and animals was found in North/Northwest region (strata) followed by Vale do Mucuri/Jequitinhonha region

Pesquisa do linfonodo sentinela usando uma técnica com base no uso do 99mtecnéssio em dextran 500 e, ou corante azul vital, em pacientes com axila clinicamente negativa

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