Question

Cobalt is present in -

• A. Vitamin \(\text{B}_{12}\)
• B. Vitamin \(\text{B}_6\)
• C. Vitamin C
• D. Vitamin A

Hint:

Since Vitamin \(\text{B}_{12}\) is synthesized exclusively by microorganisms and is not present in plant tissues, vegans and strict vegetarians are highly prone to Vitamin \(\text{B}_{12}\) deficiency (leading to pernicious anemia) and must consume fortified foods or supplements.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Certain essential vitamins contain metal ions coordinated at the center of their chemical ring structures, which are vital for their biological activity.

Step 2: Detailed Explanation:
- Vitamin \(\text{B}_{12}\) is chemically known as cobalamin (such as cyanocobalamin or methylcobalamin).
- Its molecular structure features a corrin ring coordinated around a central Cobalt ion (\(\text{Co}\)).
- This cobalt ion is essential for the vitamin's role as a coenzyme in nucleic acid synthesis, red blood cell maturation, and neurological functions.
- Vitamin \(\text{B}_6\) (pyridoxine), Vitamin C (ascorbic acid), and Vitamin A (retinol) do not contain metal ions.

Step 3: Final Answer:
Cobalt is present in Vitamin \(\text{B}_{12}\), which corresponds to option (A).