Determination of Fusarium-mycotoxins beauvericin and enniatins with liquid chromatography-tandem mass spectrometry (LC-MS/MS)

A liquid chromatography-mass spectrometric method was developed and validated to determine Fusarium mycotoxins beauvericin and enniatins (A, A(1), B, B-1) in grain samples. For the first time, a triple quadrupole mass spectrometer with multiple reaction monitoring was used for the analysis of these mycotoxins, which allowed the simultaneous structural identification of the analytes. The sample preparation involved direct purification of sample extracts with reversed-phase-solid phase extraction, enabling the avoidance of time consuming and loss-causing liquid-liquid extractions. The method validation included the determination of selectivity, repeatability, limit of detection, limit of quantification, recovery, and linearity. The developed method proved to be sensitive and repeatable for the analysis of the mycotoxins; in grain matrix. Since the method was originally developed solely for beauvericin, the recoveries of some enniatins remained rather low, except at the lowest spiking level. This was due to the natural contamination of grain matrix with enniatins B and B-1, which resulted in higher recoveries for these mycotoxins. The mean recoveries for beauvericin and enniatins A, A(1), B, and B-1 were 76- 82%, 55 -66%, 71-80%, 57 -103%, and 68-116%, respectively. The calculated limits of quantification for beauvericin and enniatins; A, A(1), B, and B-1 were 0.2, 0.2, 0.7, 0.9, and 1.5 mug/kg, respectively.