Biorremediação e biotransformação como alternativas tecnológicas para remoção de poluentes ambientais e funcionalização de compostos orgânicos

Abstract

Ensuring the quality of the world's water resources is necessary since high concentrations of pollutants in water bodies are increasingly evident. In the present work two biotechnological alternatives for the removal of pollutants through the action of filamentous fungi were addressed. The first approach consisted of the evaluation of the biosorption capacity of the metallic ions Cu(II), Fe(II), and Mn(II) by Penicillium janthinellum and Syncephalastrum racemosum biomasses. The results were analyzed by atomic absorption spectroscopy, indicating considerable percentages of removal of the ions by both microorganisms from the first hour (9.0-42.4%) and reaching high percentages (65.8-98.1%) at the end of 96 h of the experiment. The removal of Fe(II) ions stood out, with a final efficiency greater than 90%, regardless of the biomass use in its fresh form or after drying and spraying. In the second approach, the action of fungi on organic compounds was evaluated in a technique known as biotransformation. The biotransformation capabilities of the emerging pollutant ibuprofen by Aspergillus niger and S. racemosum were evaluated under different culture conditions (time and culture medium). Through the analysis of the nuclear magnetic resonance spectra of the extracts produced, the most efficient conditions for the substrate decomposition were defined, directing the later steps until the isolation of the biotransformation products. The characterization of these products led to ibu-01, a derivative isolated for the first time, with the insertion of a methoxyl group by the action of A. niger on ibuprofen, and the hydroxylated product ibu-02, resulting from the action of S. racemosum and A. niger. The filamentous fungi action for C-H bonds functionalization of some natural products such as trachylobanic acid, longifolene, and isosteviol was also investigated. For isosteviol, derived from the food additive stevioside, its transformation by the action of A. niger was verified, obtaining the hydroxylated products iso-01 and iso-02, and the dihydroxylated product iso-03, which, in the future, may have their action against biological activities evaluated. From the results is possible to infer the potential of these species in the removal of inorganic pollutants and functionalization of environmental pollutants and natural products, indicating the various possibilities of use and the interest in improving these ecological approaches.