Evaluation of Selective Media for Isolation of Staphylococcus aureus from Agricultural Products

Abstract

-Five kinds of selective media, such as mannitol salt agar (MSA), Baird-Parker agar (BPA), BairdParker supplemented with rabbit plasma fibrinogen (BPA+RPF), CHROMagar Staphylococcus aureus (CSA), and Petrifilm Staph Express count system (Petrifilm), were compared to recommend the optimum selective media for isolation of Staphylococcus aureus from agricultural products. Seventy four target and non target bacteria were inoculated on five selective media to analyze sensitivity and specificity. In the recovery test of injured S. aureus cells, S. aureus was exposed to acid (1% lactic acid for 10 min), heat (60 o C for 90s), and cold (−20 o C for 1h) conditions. And artificially contaminated agricultural products (iceberg lettuce, green pepper, and cherry tomato) was enumerated on five selective media. The sensitivity of BPA+RPF, CSA, Petrifilm, MSA, and BPA were 100%, 100%, 100%, 90.5%, 90.5%, respectively. In addition, the specificity of BPA+RPF, CSA, MSA, BPA and Petrifilm were 100%, 100%, 84.6%, 75.0%, 67.3%, respectively. However, no difference among five selective media was observed in recovery on injured S. aureus cell and enumeration from agricultural products. This results suggest that BPA+RPF and CSA are the optimum media for detection of S. aureus from agricultural products.

Bactericidal Efficacy of Fumagari OPP®, Fumigant Against Staphylococcus aureus

“…과거의 식중독 발생은 고기류와 생선 등 단백질이 풍부 한 식품에 의한 식중독이 대부분을 차지하고 있었으나, 최 근에는 과일과 채소 등에서 비롯된 식중독 사례가 증가하 고 있으며, 신선과채류를 통해 발생하는 식중독의 대부분 은 주변 환경으로부터 오염된 식품을 섭취하여 발생하는 것으로 보고되고 있다 2,3) . .…”