http://hdl.handle.net/1822/18 CEB Pesquisar o canal pesquisa http://repositorium.sdum.uminho.pt/simple-search http://hdl.handle.net/1822/10431 T&iacute;tulo: The inhibitory effect of an RGD-human chitin-binding domain fusion protein on the adhesion of fibroblasts to reacetylated chitosan films<br/><br/>Autor: Carvalho, Vera; Domingues, Lucília; Gama, Miguel<br/><br/>Resumo: Biomaterials used for tissue engineering applications must provide a structural support for the tissue development and also actively interact with cells, promoting adhesion, proliferation, and differentiation. To achieve this goal, adhesion molecules may be used, such as the tripeptide Arg-Gly-Asp (RGD). A method based on the use of a carbohydrate-binding module, with affinity for chitin, was tested as an alternative approach to the chemical grafting of bioactive peptides. This approach would simultaneously allow the production of recombinant peptides (alternatively to peptide synthesis) and provide a simple way for the specific and strong adsorption of the peptides to the biomaterial.A fusion recombinant protein, containing the RGD sequence fused to a human chitin-binding module (ChBM), was expressed in E. coli. The adhesion of fibroblasts to reacetylated chitosan (RC) films was the model system selected to analyze the properties of the obtained proteins. Thus, the evaluation of cell attachment and proliferation on polystyrene surfaces and reacetylated chitosan films, coated with the recombinant proteins, was performed using mouse embryo fibroblasts 3T3. The results show that the recombinant proteins affect negatively fibroblasts anchorage to the materials surface, inhibiting its adhesion and proliferation. We also conclude that this negative effect is fundamentally due to the human chitin-binding domain. http://hdl.handle.net/1822/10428 T&iacute;tulo: Production, characterization and application of activated carbon from brewer’s spent grain lignin<br/><br/>Autor: Mussatto, Solange I.; Fernandes, Marcela; Rocha, George J. M.; Órfão, José J. M.; Teixeira, J. A.; Roberto, Inês Conceição<br/><br/>Resumo: Different types of activated carbon were prepared by chemical activation of brewer’s spent grain (BSG) lignin using H3PO4 at various acid/lignin ratios (1, 2, or 3 g/g) and carbonization temperatures (300, 450, or 600 °C), according to a 22 full-factorial design. The resulting materials were characterized with regard to their surface area, pore volume, and pore size distribution, and used for detoxification of BSG hemicellulosic hydrolysate (a mixture of sugars, phenolic compounds, metallic ions, among other compounds). BSG carbons presented BET surface areas between 33 and 692 m2/g, and micro- and mesopores with volumes between 0.058 and 0.453 cm3/g. The carbons showed high capacity for adsorption of metallic ions, mainly nickel, iron, chromium, and silicon. The concentration of phenolic compounds and color were also reduced by these sorbents. These results suggest that activated carbons with characteristics similar to those commercially found and high adsorption capacity can be produced from BSG lignin. http://hdl.handle.net/1822/10426 T&iacute;tulo: The Weaponisation of Mycotoxins<br/><br/>Autor: Paterson, R. R. M.; Lima, Nelson http://hdl.handle.net/1822/10424 T&iacute;tulo: Pulsed electric field reduces the permeability of potato cell wall<br/><br/>Autor: Gómez Galindo, Federico; Vernier, P. Thomas; Dejmek, Petr; Vicente, A. A.; Gundersen, Martin A.<br/><br/>Resumo: The effect of the application of pulsed electric fields to potato tissue on the diffusion of the fluorescent dye FM1-43 through the cell wall was studied. Potato tissue was subjected to field strengths ranging from 30 to 500 V/cm, with one 1 ms rectangular pulse, before application of FM1-43 and microscopic examination. Our results show a slower diffusion of FM1-43 in the electropulsed tissue when compared with that in the non-pulsed tissue, suggesting that the electric field decreased the cell wall permeability. This is a fast response that is already detected within 30 s after the delivery of the electric field. This response was mimicked by exogenous H2O2 and blocked by sodium azide, an inhibitor of the production of H2O2 by peroxidases. http://hdl.handle.net/1822/10419 T&iacute;tulo: A review of current and emergent biofilm control strategies<br/><br/>Autor: Simões, M.; Simões, Lúcia C.; Vieira, M. J.<br/><br/>Resumo: Microbial adhesion to surfaces and the consequent biofilm formation has been documented in many different environments. Biofilms constitute a protected mode of growth that allows microorganisms to survival in hostile environments, being their physiology and behavior significantly different from their planktonic counterparts. In dairy industry, biofilms may be a source of recalcitrant contaminations, causing food spoilage and are possible sources of public health problems such as outbreaks of foodborne pathogens. Biofilms are difficult to eradicate due to their resistant phenotype. However, conventional cleaning and disinfection regimens may also contribute to inefficient biofilm control and to the dissemination of resistance. Consequently, new control strategies are constantly emerging with main incidence in the use of biosolutions (enzymes, phages, interspecies interactions and antimicrobial molecules from microbial origin).The present review will focus on describing the mechanisms involved in biofilm formation and behavior, deleterious effects associated with their presence, and some of the current and emergent control strategies, providing new insight of concern for food industry.