Salmonella and shigella can be differentiated from other enterobacteriaceae member by isolation on:
**Core Concept**
Salmonella and Shigella are two important pathogens within the Enterobacteriaceae family, which can cause severe gastrointestinal infections. Differentiating these organisms from other Enterobacteriaceae members is crucial for accurate diagnosis and treatment. They can be distinguished based on their ability to grow on specific media.
**Why the Correct Answer is Right**
The correct answer is based on the fact that Salmonella and Shigella can be differentiated by their ability to grow on **Bismuth Sulfite Agar (BSA)**. Salmonella species can grow on BSA, producing black colonies, whereas Shigella species cannot. This is due to the presence of a specific enzyme in Salmonella, **sulfite reductase**, which allows it to reduce sulfite ions and form black colonies.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not relevant to the differentiation of Salmonella and Shigella from other Enterobacteriaceae members.
* **Option B:** This option is incorrect because it does not accurately describe a method for differentiating Salmonella and Shigella.
* **Option D:** This option is incorrect because it is not a specific medium used for the differentiation of Salmonella and Shigella.
**Clinical Pearl / High-Yield Fact**
When performing stool cultures to diagnose gastrointestinal infections, it is essential to use selective media like BSA to differentiate between Salmonella and Shigella from other Enterobacteriaceae members.
**Correct Answer:** C. Bismuth Sulfite Agar (BSA)