Question
Short note on: Sucrose.
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Answer
One of the common disaccharides is sucrose which on hydrolysis gives equimolar mixture of D-(+)glucose and D-(-)fructose.
These two monosaccharides are held together by a glycosidic linkage between $C _1$ of $\alpha- D$ Glucose and $C _2$ of $\beta-D$ fructose.
Since the reducing groups of glucose and fructose are involved in glycosidic bond formation, sucrose is a non reducing sugar.
Sucrose is dextrorotatory but after hydrolysis gives dextrorotatory glucose and laevorotatory fructose.
Since the laevorotation of fructose (-92.4°) is more than dextrorotation of glucose (+52.5°) the mixture is laevorotatory.
Thus, hydrolysis of sucrose brings about a change in the sign of rotation, from dextro (+)
to laevo (-) and the product is named as invert sugar.
These two monosaccharides are held together by a glycosidic linkage between $C _1$ of $\alpha- D$ Glucose and $C _2$ of $\beta-D$ fructose.
Since the reducing groups of glucose and fructose are involved in glycosidic bond formation, sucrose is a non reducing sugar.
Sucrose is dextrorotatory but after hydrolysis gives dextrorotatory glucose and laevorotatory fructose.
Since the laevorotation of fructose (-92.4°) is more than dextrorotation of glucose (+52.5°) the mixture is laevorotatory.
Thus, hydrolysis of sucrose brings about a change in the sign of rotation, from dextro (+)
to laevo (-) and the product is named as invert sugar.
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