Planta Med 2010; 76 - P545
DOI: 10.1055/s-0030-1264843

Mass spectrometry in microbial metabolomic analysis as an analytical tool for dereplication strategy

E Crevelin 1, L Beraldo de Moraes 1, I Soares de Melo 2
  • 1University of São Paulo, Chemistry, Bandeirantes Avenue, 14040901 Ribeirão Preto, Brazil
  • 2Brazilian Company for Agricultural Research – Embrapa, Laboratory of Environmental Microbiology, SP Highway, 13820–000 Jaguariúna, Brazil

Metabolomics is the quantitative analysis of wide arrays of metabolites, including seoncdary metabolites, in biological samples. Metabolic profiling focuses on a group of metabolites while metabolic fingerprinting deal with global screening approach to classify samples based on metabolite patterns. The application of MS for analysis of secondary metabolites has grown over the last two decades, and today MS is the most important detector method in biotechnology [1]. Dereplication accelerates the discovery of novel natural products by eliminating repetitive work on known compounds. MS has been used for the dereplication of natural products because it is sensitive and provides information about the molecular mass, molecular formula and substructure of molecules [2], allowing dereplication of natural products at their early stages of purification and characterization. The aim of this study was to analyze metabolite profiles of crude extracts obtained from actinomycetes in differents cultivation medium by direct infusion MS and LC/MS. There are differences in the production of secondary metabolites in response to the growth conditions. The dereplication strategy for the analysis of the secondary metabolites has been developed. First, full scan total ion chromatogram (TIC), scanning m/z 100–1200, was acquired in both positive and negative modes. Ionization of compounds was better in positive mode. The dereplication was carried out in the mass range of m/z 750–900. The data suggest that the secondary metabolites located in this mass range belong to class of macrotetrolides and macrolides antibiotics (Figure 1). Compounds were isolated by a bioassay-guided fractionation using the microalga Chlorella vulgaris as test organism.

Fig.1: Chemical structures of macrotetrolides and 16-membered macrolide antibiotics

Acknowledgements: FAPESP, CAPES and CNPq

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