Aprendizagem baseada na resolução de problemas: uma experiência educacional no estudo do perfil químico dos resíduos agroindustriais da Piper Nigrum L.

Abstract

This educational research is about the characterization of the chemical profile of agro-industrial waste produced from Piper Nigrum L. production by gas chromatography−mass spectrometry (GC-MS) and Fourier Transform Ion Cyclotron mass spectrometry (FT-ICR MS) using the positive ion (ESI (+)) and negative ion ESI (ESI(-)). This characterization was developed with chemistry undergraduate students, of the Federal University of Espirito Santo, in the course of Waste Treatment in Environment, applied Problem-Based Learning methodology. The objective of this study was to bring the chemistry undergraduate students to the scientific research environment. We chose this research theme because the state of Espirito Santo is the biggest in producing and exporting black pepper to the international market. However, worldwide demand involves a manufacturing process that generates a large amount of agro-industrial waste of Piper Nigrum L. that is placed in the environment. Thus, we can discuss this issue in the educational context. The chemical profile, identified by the students, using analytical techniques, consisted mainly of the presence of three classes of secondary metabolites: amides, fatty acids and, terpenes. These substances present in the agro-industrial waste of Piper Nigrum L. are constituents of the leaves, roots, and fruits of black pepper. So, we can think about the possibility to use these wastes as an alternative biological substrate in the extraction of these substances. This study, in addition to bringing undergraduate students closer to the scientific method, aroused the interest and curiosity of the students, as they carried out all the proposed activities with zeal and dedication, acquiring new learning, and developing skills of the scientific reading, communication, and critical thinking. Therefore, we can say that the proposal for this study is favorable to the teaching of chemistry.