Resultados da pesquisa - "PEst-OE/AGR/UI0245/2014"

Catálogo de Publicações - "PEst-OE/AGR/UI0245/2014"

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  1. 1

    Novel hydrogels based on yeast chitin-glucan complex: Characterization and safety assessment

    Publicação
    por Araújo, Diana
    Outros Autores: Delgado Alves, Vitor; Lima, Sofia A.C.; Reis, Salette; Freitas, Filomena; Reis, Maria A.M.
    Chitin-glucan complex (CGC) was used for the first time for the preparation of hydrogels. Alkali solvent systems, NaOH and KOH solutions, either at 1 or 5 mol/L, were used for CGC dissolution using a freeze-thaw procedure (freezing at −20 °C and thawing at room temperature; four cycles). The CGC solutions thus obtained were subjected to dialysis that induced the spontaneous gelation of the biopolymer, yielding translucid hydrogels with a yellowish coloration. Although all CGC hydrogels exhibited porous microstructures, high water content (above 97%) and good mechanical properties, their morphology, viscoelastic properties and texture were influenced by the type of solvent system used for CGC dissolution, as well as by their ionic strength. The K-based hydrogels presented a less compact network with larger pores and exhibited lower elastic properties. The Na-based hydrogels, on the other hand, exhibited a denser structure with smaller pores and a stiffer gel structure. These results show that it is possible to prepare CGC hydrogels with differing characteristics that can be suitable for different applications. Furthermore, all hydrogels were non-cytotoxic towards L929 fibroblasts and HaCaT keratinocytes. This study demonstrates CGC can be used to prepare biocompatible hydrogels with properties render them promising biomaterials
    2020 artigo Portugal acesso aberto
  2. 2

    In vitro shoot cultures of pterospartum tridentatum as an alternative to wild plants as a source of bioactive compounds

    Publicação
    por Gonçalves, José Carlos
    Outros Autores: Coelho, Maria Teresa; Diogo, Maria da Graça; Alves, Vitor D.; Bronze, Maria Rosário; Coimbra, Manuel A. et al.
    The aim of this study was to evaluate the composition of aqueous extracts of in vitro shoot cultures and wild plants of Pterospartum tridentatum in order to promote the use of this plant material as a possible source of bioactive compounds. The extraction yield from wild plants compared with in vitro shoot cultures was lower. The total phenolic contents of in vitro shoots were significantly lower compared with those of wild plants. The phenolic profiles of in vitro shoots were very similar to those of wild plants, regardless of the source. However, taxifolin-6-C-glucoside, as well as rutin and isoquercitrin, were not present in extracts of in vitro shoots. An interesting result was the higher molar percentages of rhamnose and uronic acids detected in in vitro shoots compared with the wild plants, which can make the in vitro plant material very useful for obtaining these compounds.
    2018 artigo Portugal acesso aberto