Co-culture of microorganisms isolated from the rhizosphere of Senna spectabilis aiming to produce new bioactive metabolites

Abstract

The search for new sources of natural products have been responsible for the increased use of analytical tools that enable a rapid and efficient analysis of these complex matrixes and is of fundamental importance in the current bioprospecting programs. In this context, the methodologies associated with dereplication methodologies coupled to spectroscopic state of the art technology as well as different in vitro and in vivo bioassays are accelerating the choosing of biologically promising extracts. Our research group "NuBBE" (Nuclei of Bioassays, Biosynthesis and Ecophysiology of Natural Products) has incorporated experimental strategies and chromatographic methods to select, from our bank of extract, lead candidates for further studies. Recently the use of high performance liquid chromatography (HPLC) hyphenated with high resolution mass spectrometry (HRMS) allowed us to analyze plant and endophytic fungi extracts speeding up the selection of biologically active fractions as well as assisting on chemical composition studies of the known bioactive chemotypes and selecting those with novel molecular characteristics for further separation and purification. Innovative spectroscopic techniques using Nuclear Magnetic Resonance (NMR), recently applied on the study of dynamic complex matrixes, are being integrated with HPLC methods mainly due to their robustness, low sample amounts and spectroscopic versatilities. This project aims to understand the molecular relationships present in complex matrices generating a rational approach to study the coexistence between the rhizosphere and microorganisms that inhabit it, making it a rich source of bioactive metabolites. The rhizosphere of Senna spectabilis (Fabaceae) holds a well-known cytotoxic potential, little studied towards their chemical composition and microbial interaction. Additionally, Senna spectabilis's rhizosphere will be rationally explored from which selected microorganism will be grown in co-cultures aiming to validate their cytotoxic potential, as well as to observe unknown microbial interactions. (AU)