Isolation and Identification of Staphylococcus

As many as 20 g of each collected ready-to-eat food sample was blended with 225 mL of buffered peptone water (Merck, Germany). Next, the solutions were homogenized using a stomacher (Interscience, Saint-Nom, France). Consequently, 5 mL of the produced solution was transferred to 50 mL of Trypticase Soy Broth (TSB, Merck, Germany) supplemented with 10% NaCl and 1% sodium pyruvate, which was then incubated for 18 h at 35 °C. Next, a loopful culture was transferred to the Baird-Parker agar supplemented with an egg yolk tellurite emulsion (Merck, Germany) and incubated at 37 °C for about 24 h. Black shiny colonies surrounded with 2- to 5-mm clear zones were identified based on gram staining, hemolytic activity on the sheep blood agar (Merck, Germany), catalase test, coagulase test (rabbit plasma), oxidase test, OF glucose test, bacitracin sensitivity test (0.04 U), mannitol fermentation on the Mannitol salt agar (Merck, Germany), urease activity, nitrate reduction, phosphatase, deoxyribonuclease (DNase, Merck, Germany) test, Voges-Proskauer (VP) (Merck, Germany) test, and carbohydrate (xylose, sucrose, trehalose and maltose, fructose, lactose, and mannose) fermentation test [13 (link)].