Antimicrobial resistance of staphylococcus aureus in dairy products from Kedah / S. Sasidharan and B. Prema

This research focused on the isolation and characterization of S. aureus from dairy products using conventional methods and also on their antimicrobial resistance pattern. A total of 50 dairy samples was used for the isolation of the S. aureus before subjected to an antibiotic susceptibility test. Of 50 samples examined, 5 (10 %) were contaminated with S. aureus. Sample 29 showed resistance to methicillin and vancomycin. Sample 18 showed intermediate response to tetracycline. The other samples were susceptible to all the antibiotics tested. Broth microdilution test was conducted on all the 5 samples using ampicillin and tetracycline to measure the Minimum Inhibitory Concentration (MIC). Samples 2, 10, 14, 18 and 29 that were tested with tetracycline showed MIC of 25.00 µg/mL, 6.25 µg/mL, 6.25 µg/mL, 3.13 µg/mL and 12.50 µg/mL respectively. The understanding of antimicrobial resistance of S. aureus enables the development of preventive strategies to limit the existing resistance and to avoid the emergence of new strains of resistant S. aureus. This calls for the better control of sources of food contamination.