Polyphasic approach including maldi-tof mass spectrometry to characterise aflatoxigenic species of aspergillus section flavi Conference Paper uri icon

abstract

  • Aflatoxins are toxic compounds which are produced as secondary metabolites by the fungi Aspergillus flavus, A. parasiticus and A. nomius growing on a variety of food products and are known to be carcinogenic, mutagenic, teratogenic and immunosuppressive1,2. Aspergillus is a large genus, with a complex taxonomy. The genus is easily identified by its characteristic conidiophore, but species identification and differentiation is complex, mainly because it is traditionally based on a range of morphological features. One includes the aflatoxigenic species referred above A. flavus, A. parasiticus and A. nomius, which cause serious problems in agricultural commodities, and the other one includes the non-aflatoxigenic species A. oryzae, A. sojae and A. tamarii, traditionally used for production of fermented foods. Species from A. flavus group are morphologically and genetically very similar, and are therefore difficult to differentiate by both cultural and molecular methods. Matrix Assisted Laser Desorption Ionization Time-of-Flight (MALDI-TOF) Mass Spectrometry has already shown high potentialities in discriminating very closely related taxa. In this work is presented a polyphasic approach including MALDI-TOF MS to discriminate A. flavus group strains.

publication date

  • January 1, 2009