Question

Sucrose on hydrolysis gives:
A. glucose and maltose
B. glucose and lactose
C. glucose and fructose
D. only glucose

Answer 1

Hint: Sucrose is a disaccharide which is formed by the addition of a glucose molecule and a fructose molecule by the formation of a glycosidic bond between them, with the release of a water molecule from it. Thus, sucrose formation is a result of the dehydration process.

Complete step by step answer:

The glycosidic bond formation takes place in between the first carbon of the $\alpha - D - $ glucose molecule and second carbon of the $\beta - D - fructose$ molecule. The hydrolysis of the disaccharide sucrose gives an equimolar mixture of $D - ( + ) - $ glucose and $D - ( - ) - $ fructose. The reaction that takes place here is as follows:
${C_{12}}{H_{22}}{O_{11}} + {H_2}O \to {C_6}{H_{12}}{O_6} + {C_6}{H_{12}}{O_6}$
(Sucrose) (Glucose) (Fructose)
These two monosaccharides formed are held together by a glycosidic linkage between ${C_1}$ of $\alpha - $ glucose and ${C_2}$ of $\beta - $ fructose. Since, the reducing groups of glucose and fructose are involved in glycosidic bond formation, sucrose is a non-reducing sugar. The hydrolysis of sucrose brings about a change in the sign of rotation, from dextro rotator (+) to laevo rotator (-) and the product is named as the invert sugar.
The two monosaccharides are joined together by an oxide linkage formed by the loss of a water molecule. Such a linkage between the two monosaccharide units through oxygen is known as a glycosidic linkage.
Thus, the correct option is C. glucose and fructose.

Note:
For human consumption, sucrose is extracted and refined from either sugarcane or sugar beet. The sugar mills that are present in the tropical regions near where sugarcane is grown, the cane is crushed there and raw sugar is produced which is shipped to other factories for refining into pure sucrose and for the removal of toxic substances and impurities.