Carqueja (Pterospartum tridentatum) is an endemic species and various bioactive compounds have been identified in its aqueous extract. The aim of this study was to protect the natural antioxidants from the aqueous extract of carqueja by encapsulation in Ca-alginate microbeads and Ca-alginate microbeads containing 10% and 20% (w/v) of inulin. The microbeads produced by electrostatic extrusion technique had an average diameter from 625 μm to 830 μm depending on the portion of inulin. The sphericity factor of the hydrogel microbeads had values between 0.014 and 0.026, while freeze dried microbeads had irregular shape, especially those with no excipient. The reduction in microbeads size after freeze drying process (expressed as shrinkage factor) ranged from 0.338 (alginate microbeads with 20% (w/v) of inulin) to 0.523 (plain alginate microbeads). The expressed radical scavenging activity against ABTS and DPPH radicals was found to be between 30% and 40% for encapsulated extract, while the fresh extract showed around 47% and 57% of radical scavenging activity for ABTS and DPPH radicals, respectively. The correlation between antioxidant activity and the total phenolic content were found to be positive (in both assay methods, DPPH and ABTS), which indicate that the addition of inulin didn't have influence on antioxidant activity. The presence of inulin reduced stiffness of the hydrogel, and protected bead structure from collapse upon freeze-drying. Alginate-inulin beads are envisaged to be used for delivery of aqueous P. tridentatum extract in functional food products.

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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.

Maria Teresa Coelho ae RESUMO. Este artigo relata algumas experiências de utilização de entrevistas com crianças e reflete sobre sua utilidade e limitações. A entrevista com crianças é uma técnica ainda relativamente pouco explorada na literatura. Em nosso próprio trabalho -baseado principalmente em observação direta -entrevistas individuais ou em grupo foram utilizadas esporadicamente, a título de complementar dados observacionais, oferecer material qualitativo para exploração posterior ou responder a certos tipos de pergunta. Com base nessa experiência, estruturamos este texto em termos de situações-exemplo ou casos, dos quais alguns ressaltam aspectos problemáticos ou limitadores, e outros ilustram empregos dessa técnica que consideramos bem-sucedidos.Palavras-chave: entrevista com crianças, metodologia, relato verbal. USING INTERVIEWS WITH CHILDRENABSTRACT. This paper reports some experiences with the use of interviews with young children, and reflects on the usefulness and limitations of this technique. Interviews with children are relatively underexplored in the literature. In our own work, which is mainly based in direct observation, interviews were used as a complementary resource, for comparisons with observational data, in order to obtain qualitative data for further exploration or to answer certain types of questions. On the basis of these experiences, the paper was structured in the form of examples or cases, some of which highlight limitations or problems of the technique, and others present what we consider successful utilizations.