Question

Glycosidic linkage between C\(_1\) of \(\alpha\)-glucose and C\(_2\) of \(\beta\)-fructose is found in:

• A. maltose
• B. sucrose
• C. lactose
• D. amylose

Hint:

Sucrose is a non-reducing sugar as both anomeric carbons of glucose and fructose are involved in glycosidic linkage.

Answer 1

The Correct Option is B

Step 1: Understanding Glycosidic Linkage
Glycosidic bonds are covalent bonds formed between sugar molecules through dehydration synthesis.
The type of glycosidic bond determines the digestibility and function of the disaccharide.
Step 2: Comparison of Linkages
Maltose consists of two glucose units linked by a C\(_1\)-C\(_4\) \(\alpha\)-glycosidic bond.
Sucrose has a glycosidic bond between C\(_1\) of \(\alpha\)-glucose and C\(_2\) of \(\beta\)-fructose.
Lactose is made up of galactose and glucose with a C\(_1\)-C\(_4\) glycosidic bond.
Amylose consists of glucose monomers linked by C\(_1\)-C\(_4\) \(\alpha\)-glycosidic bonds.
Final Answer: Since sucrose contains an \(\alpha\)-glucose and a \(\beta\)-fructose linked at C\(_1\)-C\(_2\), the correct answer is (B).

Answer 2

Sucrose contains the glycosidic linkage between C₁ of α-glucose and C₂ of β-fructose.

Sucrose is a disaccharide formed by the condensation of one molecule of α-glucose and one molecule of β-fructose. The unique glycosidic bond in sucrose is an α(1→2)β linkage, meaning the anomeric carbon (C₁) of the α-glucose unit is linked to the anomeric carbon (C₂) of the β-fructose unit.

This bond formation locks both the glucose and fructose units in their respective ring forms and prevents them from mutarotation, which is why sucrose is a non-reducing sugar. The α(1→2)β glycosidic bond is crucial in defining the chemical and physical properties of sucrose, making it an important sugar in biological systems and the food industry.