Biotransformation of the triketone herbicide Mesotrione by a Bacillus strain. Metabolite profiling using liquid chromatography/electrospray ionization quadrupole-time of flight mass spectrometry.

Stéphanie Durand (1) , Bertrand Legeret (1) , Anne-Sophie Martin (1) , Martine Sancelme (1) , A.M. Delort (1) , Pascale Pascale Besse, P. Besse-Hoggan Besse-Hoggan (1) , Bruno Combourieu (1)

1 SEESIB - Synthèse et étude de systèmes à intêret biologique

The metabolic pathway involved in the biotransformation of the herbicide mesotrione by the bacterial strain Bacillus sp. 3B6 was investigated by a reliable liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry (LC/ESI-QTOF-MS) method. The LC/ESI-MS method, both in positive and negative mode, with the assistance of MS2 fragments and isotopic pattern analyses, allowed us to identify five metabolites. This work constitutes the first complete monitoring of mesotrione degradation kinetics. Among the transformation products found by both techniques, one was formed by intramolecular cyclization between a hydroxylamine and a keto function, which is quite a rare biological reactivity process. For each identified metabolite, a fragmentation pathway is proposed for negative and positive mode

Domaines: Chimie analytique

Stéphanie Durand, Bertrand Legeret, Anne-Sophie Martin, Martine Sancelme, A.M. Delort, et al.. Biotransformation of the triketone herbicide Mesotrione by a Bacillus strain. Metabolite profiling using liquid chromatography/electrospray ionization quadrupole-time of flight mass spectrometry.. Rapid Communications in Mass Spectrometry, 2006, 20, pp.2603-2616. ⟨10.1002/rcm.2627⟩. ⟨hal-00118463⟩