Rapid screening of fermentation broths for flavones using tandem mass spectrometry

Fermentation broth extracts were rapidly screened for the presence of daidzein and genistein with an approach utilizing the desorption chemical ionization (DCI) and thermospray (TS) ionization modes in conjunction with tandem mass spectrometry (MS/MS). DCI/MS/MS techniques are utilized to rapidly determine the presence of both flavone structures, while TS/liquid chromatographic/MS/MS techniques are utilized for further elucidation and confirmation of the flavone structures. The method is based on the fact that flavone structures undergo similar collisionally activated dissociations (CAD) corresponding to cleavage through the benzopyrone substructure and loss of CO and H2O molecules. A direct comparison, both chromatographic and spectral, to authentic standards is used to confirm the presence of daidzein and genistein.