Rapid whole protein quantitation of staphylococcal enterotoxins A and B by liquid chromatography/mass spectrometry

Staphylococcus aureus is an important pathogen and has been indicated as the fifth causative agent of food-borne human illness throughout the world. Staphylococcal enterotoxins (SEs) are toxic compounds excreted mainly by strains of S. aureus. Among these toxins, enterotoxins A (SEA) and B (SEB) are both of the most prevalent compounds in staphylococcal food poisoning. In this work, reverse phase liquid chromatography coupled to ESI mass spectrometry (LC–ESI/MS) has been applied for its rapid identification and quantification. Limit of detection (LOD) values were 0.5 and 0.2 ng for SEA and SEB, respectively and limit of quantification (LOQ) value was 1 ng for both enterotoxins. SEA and SEB have been analyzed as intact proteins in milk and fruit juices. Analytical methods are essential for routine monitoring purposes and safeguard public health and the proposed technique can detect and quantify successfully SEA and SEB in food samples.

► Staphylococcus aureus toxins are one of the most important causes of food poisoning in the world.
► SEA and SEB are the most frequently toxins involved in foodborne diseases.
► We used LC/MS–MS for the rapid identification and quantification of SEA and SEB.
► LC/MS–MS method has been applied successfully in food matrices to quantify SEs.