Question

Match List-I with List-II
List-I (Milk enzymes):
(A) Alkaline phosphatase
(B) Plasmin
(C) Lactoperoxidase
(D) Superoxide dismutase
List-II (Location):
(I) Plasma
(II) Serum
(III) Fat globule membrane
(IV) Casein micelles
Choose the correct answer from the options given below:

• (A) - (III), (B) - (IV), (C) - (II), (D) - (I)
• (A) - (II), (B) - (III), (C) - (I), (D) - (IV)
• (A) - (III), (B) - (IV), (C) - (I), (D) - (II)
• (A) - (I), (B) - (III), (C) - (IV), (D) - (II)

Hint:

Remember that Alkaline Phosphatase is associated with fat, so it is located on the Fat Globule Membrane.
Plasmin is a protease that degrades casein, so it is naturally bound to Casein Micelles.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Milk contains a variety of indigenous enzymes distributed across its different physical phases: the fat phase, the colloidal casein phase, and the soluble whey (serum/plasma) phase.
Detailed Explanation:
Let us match each milk enzyme with its typical structural location in milk:
- (A) Alkaline phosphatase: This enzyme is lipophilic and is primarily located on the milk fat globule membrane (FGM) (III). During cream separation, it concentrates with the fat phase.
- (B) Plasmin: This is a major proteolytic enzyme in milk. It is primarily bound to the casein micelles (IV), where it can slowly degrade \(\beta\)-casein and \(\alpha_{s1}\)-casein, influencing cheese ripening and age-gelation in UHT milk.
- (C) Lactoperoxidase: This is one of the most abundant enzymes in milk. It is soluble and is located in the skim milk phase or milk plasma (I). It is part of the lactoperoxidase antimicrobial system.
- (D) Superoxide dismutase: This antioxidant enzyme is primarily located in the milk serum (II) (the soluble whey phase).
Combining these individual matches:
\[ (A) \rightarrow (III), \quad (B) \rightarrow (IV), \quad (C) \rightarrow (I), \quad (D) \rightarrow (II) \] This matches option (C).

Step 2: Final Answer:
The correct match is (A) - (III), (B) - (IV), (C) - (I), (D) - (II).