A QuEChERS Cyanin based Chromogenic Method for the Sensitive Identification of MRSA from Various Food Sources and its Molecular Characterization

Abstract

Methicillin resistant Staphylococcus aureus harbouring other virulence factors in food is a serious threat to food safety. Delayed detection of MRSA may lead to fatal consequences due to the challenging treatment methods. To address the issue, early prognosis is prerequisite. We report one step QuEChERS detection method wherein, a media with selective agents such as cefoxitin, cyanidin, lithium chloride and methicillin (CCLM) was formulated for the specific cultivation and detection of MRSA within 5 hours. Direct application of the newly developed method was tested by screening food for MRSA and its comparison with conventional biochemical and molecular characterization. Growth of MRSA in the CCLM media was observed within 4 hours. This highly specific method is sensitive to detect 104 CFU/mL visually and 101 CFU/mL spectrophotometrically. 25% of food samples harboured MRSA which points to an immediate need of consideration by the authorities. The newly designed QuEChERS cyanin based chromogenic detection system is unequivocal with the conventional and molecular method of MRSA detection and can be of great use in diagnostic and in food safety laboratories.