Semi-synthesis of N-alkyl-kappa-carrageenan derivatives and evaluation of their antibacterial activity.

In this article, we describe the semi-synthesis of N-alkyl-kappa-carrageenan derivatives and their antibacterial activity against Staphylococcus aureus (ATCC 6538), Escherichia coli (ATCC 8739), and Pseudomonas aeruginosa (ATCC 9027). Kappa-carrageenan was submitted to partial acid hydrolysis promoting the selective cleavage of α-glycosidic bonds involving 3,6-anhydro-α-D-Galp units, giving rise to reducing low-molecular weight polysaccharide fragments, which were reacted with alkylamines of varying chain lengths by reductive amination. The carrageenan derivatives were characterized by HPSEC-MALLS-RID and 1D and 2D 1H and 13C NMR spectroscopy. The antibacterial activity of N-alkyl-kappa-carrageenan derivatives was compared with N-alkyl-(1-deoxylactitol-1-yl)-amines using a microdilution test, which indicated that inhibitory activity was dependent on the degree of substitution by hydrophobic groups at the polysaccharide structure. Comparing the effect of different N-alkyl chains, those with longer chains showed higher activity.

Active methodology and blended learning: An experience in pharmaceutical care.

BACKGROUND AND PURPOSE: The aim of this study was to analyze the implementation of an active methodology in a blended model of education in the teaching-learning processes of students enrolled in two disciplines: Pharmaceutical Care I and Pharmaceutical Care II, both part of the undergraduate Bachelor of Pharmacy program at the Federal University of Paraná. EDUCATIONAL ACTIVITY AND SETTING: The study design was quasi-experimental, prospective, comparative, following a pre/posttest format, where Pharmaceutical Care classes were the intervention. Identical pre- and post-intervention tests were designed based on Anderson and Krathwohl's (2001) revision of Bloom's taxonomy, and according to the three levels of the cognitive domain: remember and understand; apply and analyze; evaluate and create. FINDINGS: Participants were 133 students enrolled in the two Pharmaceutical Care classes. A significant difference between pre- and posttest results was observed, showing an increase in students' performance in the applied tests at all cognitive levels. This is the first study of its kind involving Pharmaceutical Care and Blended Learning. DISCUSSION AND SUMMARY: By comparing the results of the diagnostic and summative assessments based on Bloom's taxonomy at all levels of the cognitive domain, positive results were observed regarding the students' performance in the two disciplines (Pharmaceutical Care I and II).