TraceMedia™ TCBS/ SS is a pre-poured agar medium on 90mm petri dishes used for culturing and isolating Vibrio, Salmonella, and Shigella from clinical specimens and research purposes.
- TraceMedia™ TCBS/ SS consists of Thiosulfate Citrate Bile Salts Sucrose Agar (TCBS) and Salmonella Shigella Agar (SS).
- Thiosulfate Citrate Bile Salts Sucrose Agar (TCBS): This medium is used for selective culturing to isolate Vibrio. It differentiates V. cholerae from other Vibrio species based on their ability to ferment sucrose.
- Salmonella Shigella Agar (SS): This selective medium is used for the isolation and differentiation of Salmonella and Shigella.
- TraceMedia™ TCBS/ SS contains proteose peptone and yeast extract, providing nitrogen compounds, complex B vitamins, and other essential growth nutrients while inhibiting gram-positive bacteria and coliforms. Sodium thiosulfate acts as a good sulfur source, combined with iron citrate, which detects the production of hydrogen sulfide. Bromothymol blue and thymol blue serve as pH indicators.
- The alkaline pH of the medium enhances the recovery of V. cholerae and V. alginolyticus, resulting in yellow colonies on TCBS Agar due to sucrose fermentation. V. parahaemolyticus and V. vulnificus do not ferment sucrose and produce blue-green colonies.
- SS Agar is a selective medium in which gram-positive bacteria are inhibited by bile salts, resulting in vibrant green and sodium citrate. Peptone provides a source of nitrogen and carbon, long-chain amino acids, vitamins, and necessary nutrients for growth. Lactose is a fermentable carbohydrate. The vibrant green color, bile salts, and thiosulfate selectively inhibit gram-positive bacteria and coliforms. Some enteric organisms reduce sodium thiosulfate to form sulfite and H2S gas.
- After incubation for the specified time, typically 16-24 hours, observe the colony growth on the surface of the petri dish.
- Further identification of isolated bacteria requires appropriate testing methods.