Question

Given below are two statements :
Statement I: Maltose has two\(α-D-glucose\) units linked at \(C_1\) and \(C_4\) and is a reducing sugar.
Statement II: Maltose has two monosaccharides : 
\(α-D-glucose\) and \(β-D-glucose\) linked at \(C_1\) and \(C_6\) and it is a non-reducing sugar.
In the light of the above statements, choose the correct answer from the options given below.

• A. Both Statement I and Statement II are true
• B. Both Statement I and Statement II are false
• C. Statement I is true but Statement II is false
• D. Statement I is false but Statement II is true

Answer 1

The Correct Option is C

To determine the accuracy of the statements provided, let's examine each statement based on the chemistry of maltose.

1. Statement I: Maltose has two \( \alpha-D \)-glucose units linked at \( C_1 \) and \( C_4 \) and is a reducing sugar.
   • Structure of Maltose: Maltose is a disaccharide composed of two glucose molecules. Specifically, it consists of two \( \alpha-D \)-glucose units.
   • Linkage: The glucose units are connected by a glycosidic bond between the \( C_1 \) of one glucose and the \( C_4 \) of the other glucose, termed as an \( \alpha(1 \rightarrow 4) \) glycosidic bond.
   • Reducing Nature: Maltose is classified as a reducing sugar because it contains a free anomeric carbon on the second glucose unit, which can undergo oxidation.
   • Therefore, this statement is true.
2. Statement II: Maltose has two monosaccharides: \( \alpha-D \)-glucose and \( \beta-D \)-glucose linked at \( C_1 \) and \( C_6 \) and it is a non-reducing sugar.
   • Misconception in Structure: This statement erroneously describes the composition of maltose. In reality, maltose consists of two \( \alpha-D \)-glucose units, not a mix of \( \alpha-D \) and \( \beta-D \) glucose.
   • Incorrect Linkage and Nature: The linkage and sugar characterization in this statement are incorrect. The \( C_1 \) to \( C_6 \) linkage is not characteristic of maltose. Also, maltose indeed is a reducing sugar, not non-reducing.
   • Hence, this statement is false.

Conclusion: Based on the analysis, Statement I is true because it accurately describes the structure and properties of maltose, whereas Statement II is false due to incorrect details regarding maltose's composition and properties.

Therefore, the correct answer is: Statement I is true but Statement II is false.