Occurrence and characterization of staphylococcus aureus in meat and meat products marketed in Mansoura, Egypt

ABSTRACT

The present study aims to evaluate the occurrence and characterize Staphylococcus aureus in meat and meat products marketed in Mansoura, Egypt based on their antimicrobial-resistance pattern and production of enterotoxins. A total of 250 meat samples, categorized as 80 fresh beef samples besides 85 ground beef and 85 beef burger purchased from supermarkets and butchers' shops distributed in Egypt for isolation of Staphylococcus aureus. All isolates were screened for susceptibility to twelve antimicrobial discs. Minimal inhibitory concentration was carried out by twofold serial dilution in nutrient broth. Plasmid and genomic DNA| extraction were done. Polymerase chain reactions were performed for amplification of enterotoxin-encoding genes [sec and seg] Twenty five samples were isolated and identified as S. aureus. Sixty eight isolates were multidrug resistant since they were resistant to at least three different antimicrobial classes. Plasmids isolation from all isolates revealed that 76% of these isolates harbored plasmids. Fifteen isolates [60%] exhibited similar plasmid band size. The size of this plasmid was approximately 23 kbp. For seg gene, it was amplified in 8 isolates [32%] of S. aureus isolates at 550 bp. Five [63%] of the isolates harbored seg gene were multidrug resistant. On the other hand, none of the S. aureus isolates harbored sec gene. The present study confirmed the high prevalence of newly discovered enterotoxin genes [seg] in meat derived staphylococcus aureus and the association between the presence of this gene and multiple drug resistant phenomena