Biofilmes de Cunninghamella e sua versatilidade como biocatalisador em estudos de quimiodiversidade, metabolismo e biorremediação

Abstract

Introduction: Cunninghamella is a filamentous fungi genus capable of metabolizing a huge variety of xenobiotics in a regio- and stereselectively manner, due to its monooxygenase enzymatic system Cytochrome P450, analogue to mammalians, and its conjugation enzymes. It can be considered, then, as one of the best microbial models documented in biotransformations aiming production of chemodiverse derivatives, mammalian metabolites and in environmental pollutants bioremediation. OBJECTIVES: Thus, the general objective was to apply Cunninghamella species as biocatalyst in generation of quimiodiverse derivatives from morin, microbial model of mammalian metabolism of clonazepam and bioremediator of l-cyhalothrin. Methodology: Free cells and biofilms of C. echinulata ATCC 9244 and C. elegans DSM1908 were grown in PDSM and SDB liquid medium and applied as biocatalysts in these reactions. Flavonoid derivatives and mammalian benzodiazepine metabolites were identified and characterized by High Performance Liquid Chromatography coupled to High Resolution Mass Spectrometry, and their biotransformation kinetics were studied. Pesticide degradation products were identified and characterized by Gas Chromatography coupled to Mass Spectrometry and Nuclear Magnetic Resonance 19F. Results and discussion: 7-methylmorin, morin-3-O-glycoside, morin-7-O-glycoside, hydroxy-morin and hydroxy-flavanone derivatives were obtained from biotransformation with free fungal cells and biofilms, being hydroxy-morin and hydroxy-flavanone derivatives derived exclusively from bioprocessing with biofilms. As mammalian metabolites, 7-aminoclonazepam and 7-acetoamide clonazepam were obtained, and fungal biofilms were capable of exclusively producing 7- aminoclonazepam. In these studies, reaction catalyzed by biofilms showed higher yield. The pesticide l-cyhalothrin was degraded via hydrolysis of central ester bond biocatalysed by fungal cells, yielding its acid and alcohol moieities. Conclusions: Cunninghamella proved to be an effective biocatalyst in these three fields here proposed, with biofilms evidenced as an important strategy for greater enzymatic production and reactional selectivity.