What are the hydrolysis products of the following ? Lactose
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Solution and Explanation
• Lactose is a disaccharide commonly found in milk, consisting of two monosaccharide units.
• Hydrolysis involves the breaking of the glycosidic linkage by the addition of a water molecule.
• This reaction is usually catalyzed by dilute acids or the enzyme lactase.
Step 1: Determine the structural units of Lactose
Lactose is composed of one molecule of D-galactose and one molecule of D-glucose.
Specifically, these units are linked by a \(\beta\)-1,4-glycosidic bond (between C1 of galactose and C4 of glucose).
Step 2: Describe the chemical hydrolysis
When lactose reacts with water in the presence of the enzyme lactase or an acid catalyst: \[ C_{12}H_{22}O_{11} + H_{2}O \rightarrow C_{6}H_{12}O_{6} + C_{6}H_{12}O_{6} \]
The glycosidic bond is cleaved, yielding an equimolar mixture of \(\beta\)-D-galactose and \(\beta\)-D-glucose. The final answer is Galactose and Glucose.
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