Abstract A sulfated polysaccharide fraction from the red alga Gracilaria intermedia (PLS) was obtained by papain digestion (60 °C, 30 min). The extract was subjected to colorimetry and turbidimetry analysis, Fourier transform infrared (FTIR) spectroscopy, 1H, 13 C and 2D 1H COSY nuclear magnetic resonance (NMR) and gas chromatography/mass spectrometry analysis. Antioxidant activity tests were performed (chelation of ferrous ion, total antioxidant capacity, and scavenging of DPPH radicals); significant activity of the extract indicated that these polysaccharides may be used as non-synthetic antioxidants. The rheological behavior of aqueous polysaccharide solutions was studied at 25 ± 1 °C using steady-shear and dynamic oscillatory measurements. All the solutions analyzed showed pseudoplastic behavior and potential to act as a thickening agent, as proved through a preliminary comparison with a commercial product used for this application.

O Projeto "Aprendiz" é uma iniciativa do Programa de Educação Tutorial da Biologia da UFC, cuja ação de destaque é o incentivo à reativação de laboratórios de aulas práticas de ciências em escolas públicas de Fortaleza. O objetivo desta pesquisa é investigar as expectativas e dificuldades dos docentes para a implantação de atividades experimentais, durante a aplicação do "Projeto Aprendiz", bem como a superação destes obstáculos. Buscamos desvelar o potencial que a interação universidade/escola pública, professores e licenciandos possui para a formação de docentes de Ciências e Biologia. Apesar das diversas dificuldades, o trabalho conjunto de professores em exercício e futuros docentes trouxe contribuição para a formação de ambos. Com a pesquisa, professores, licenciandos e pesquisadores tiveram a possibilidade de expressar suas concepções e refletir sobre a realização de atividades práticas nas escolas públicas.

The "Apprentice Project" is an initiative of the Ceará Federal University (UFC) for Tutorial Biology Education, which focus on promoting incentives to reactivate science practice lab classes in public schools in the city of Fortaleza, Brazil. The objective of this research is to investigate the expectations and difficulties that some teachers had found in implementing experimental activities during the Apprentice Project, as well as to overcome those difficulties. We tried to determine the potential that the interaction among university, public school, teachers, and pre-service teachers has on science/biology teacher education. Despite the difficulties, the collaborative work contributed to the education of teachers and pre-service teachers. Due to this research, teachers, pre-service teachers, and researchers had the possibility of expressing their conceptions and reflecting on the experimental activities in public schools.