Question

The bacteriological selective media are used for the isolation and identification of Salmonella from seafood are
A. BSA
B. XLD agar
C. HEA
D. TCBS
E. EMB
Choose the correct answer from the options given below:

• A. A and B only
• B. D and E only
• C. A, B and C only
• D. D and E only

Hint:

Remember:
- Salmonella selective media: BSA, XLD, HEA.
- Vibrio selective media: TCBS.
- Coliform selective media: EMB, MacConkey.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Detecting enteric pathogens like Salmonella in seafood requires specific selective and differential growth media to suppress background flora while promoting the growth of the target bacteria.

Step 2: Detailed Explanation:
Let us evaluate each bacteriological medium listed:
- A. BSA (Bismuth Sulfite Agar): Highly selective and differential medium designed specifically for the isolation of Salmonella species.
- B. XLD agar (Xylose Lysine Deoxycholate agar): Standard selective and differential medium used for isolating and identifying Salmonella (which produces characteristic red colonies with black centers due to \(\text{H}_2\text{S}\) production).
- C. HEA (Hektoen Enteric Agar): Highly selective medium used to differentiate Salmonella and Shigella from other enterics.
- D. TCBS (Thiosulfate Citrate Bile Salts Sucrose agar): Specific selective medium for isolating Vibrio species.
- E. EMB (Eosin Methylene Blue agar): General-purpose selective/differential medium for coliforms and E. coli.
Therefore, BSA, XLD, and HEA are the media used for Salmonella isolation.

Step 3: Final Answer:
The correct combination is A, B, and C only, which corresponds to option (C).