Antimicrobial Resistance of Coagulase-Negative Staphylococci Isolated from Spontaneously Fermented Sausages

The antimicrobial susceptibility of coagulase-negative staphylococci isolated from spontaneously fermented sausages was assessed using both traditional and molecular methods. Isolates were tested for sensitivity to vancomycin, ampicillin, erythromycin, tetracycline, gentamycin and oxacillin by the disk diffusion method and quantitative-qualitative epsilometer test. PCR was used for the detection of resistance genes mecA, ermB, tetK and tetM. The identified coagulase-negative staphylococci were Staphylococcus epidermidis (69 %), S. capitis (5 %) and S. warneri (2.5 %). S. epidermidis showed a high rate of phenotypical resistance to tetracycline and erythromycin (44.4 % of strains). Molecular evaluation of resistance determinants revealed tetK or tetM genes in eight S. epidermidis strains. Although S. epidermidis is not classical food poisoning bacteria, its presence in food could be of public health significance due to the possible spread of antimicrobial resistance determinants. Our findings implicate that spontaneous meat fermentation could result in products with a potential hazard to consumers.