This document discusses disaccharides, which are formed through a condensation reaction between two monosaccharides that results in the removal of a water molecule. It classifies the main disaccharides - sucrose, lactose, and maltose. Sucrose is formed from glucose and fructose and is non-reducing. Lactose is formed from glucose and galactose and is reducing. Maltose is formed from two glucose molecules and is also reducing. The document provides the structures and functions of these three disaccharides.

1. 1. • DISACCHARIDES
2. • FORMATION
3. • CLASSIFICATION
A. SUCROSE
B. LACTOSE
C. MALTOSE
4. •BIBLIOGRAPHY

2.  When two monosaccharide are combined by
Glycosidic linkage, a disaccharide is formed.
 Therefore they yield two molecules of same
or different monosaccharide on hydrolysis.
 General formula of Disaccharides :
Cn(H2O)n-1
 The disaccharides just like monosaccharides
are white crystalline, sweet solids. However,
even though they are soluble in water, they
are too large to pass through cell
membranes.

3.  Disaccharides are formed when two
monosaccharides are joined together and a
molecule of water is removed, a process
known as dehydration reaction.
 For example;
Milk sugar (lactose) is made from glucose
and galactose.
 Sugar from sugar cane and sugar beet
(sucrose) is made from glucose and fructose.
 Maltose, another notable disaccharide,is
made up of two glucose molecules.

4.  There are two different types of
disaccharides:
 I. Reducing disaccharides, in which one
monosaccharide, still has a free hemiacetal
unit.
Example: i. LACTOSE
ii. MALTOSE
 II. Non-reducing disaccharides, in which
neither monosaccharide has a free hemiacetal
unit.
Example: i. SUCROSE

5. .
The glucose part had the aldehyde at carbon1
,and the fructose part had the ketone group at
carbon 2. Since the linkage is 1,2, neither group
is free. Therefore, sucrose is not a reducing
sugar.

6.  The molecule is a disaccharide derived from
glucose and fructose with the molecula formula
C12H22O11.
 Sucrose is commonly known as table sugar.
 It is a white, odourless, crystalline powder with
a sweet taste.
 FUNCTIONS
 Used in syrup preparation, tablet manufacture,
nutrient and demulcent .
 Sucrose is also used in preparation of dextran
(apolysaccharide used as plasma substitute).

7. STRUCTURE:
It has a 1,4- glycosidic linkage, acts as a reducing sugar
because both of the original aldehyde group were on
carbon 1, and one of them is free to react.

8.  Lactose is a disaccharide derived from the
condensation of Galactose and Glucose
 Lactose is commonly called Milk Sugar.
 It is Dextrorotatory
 Lactose requires you have an enzyme called
lactase to digest the disaccharide.
FUNCTIONS
 Widely used in food industry.
 Also used as filler in tablets

9. STRUCTURE:
The aldehyde groups are at carbon 1 in each of the original
glucose molecules. Since the linkage is 1,4, one free aldehyde
group remains. Therefore, maltose acts as a reducing sugar.

10.  Maltose, is a disaccharide formed from two
units of glucose.
 Maltose is commonly called Malt Sugar.
 It is produced commercially by hydrolysis of
starch.
FUNCTIONS
 Converted to glucose and used as an energy
source for growing embryo in seed.
 Used in alcohol production.