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Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)

1) Maltose = malt-sugar

• Is a reducing disaccharide formed from two units of glucose joined with an

(1→4) linkage

• Chemically, it is 4-O-(-D-Glucopyranosyl)-D-glucopyranose.

• It does not occur free in nature. It occurs in germinating cereals as a result of

amylase enzyme on starch.

• It is present as a component of polysaccharides such as starch, dextrin from

which it is liberated as an end product of the action of amylase.

4-O-( -D-glucopyranosyl)-D-glucopyranose

Preparation: It is prepared from starch by partial hydrolysis using malt

o
(containing enzyme salivary amylase or pancreatic amylase, -Amylase) at 55 C.
The solution is boiled to coagulate proteins, filtered, concentrated and left to

crystallize.

Properties: Soluble in water.

• It is a reducing sugar having a potential aldehyde group:

a) Reduces Fehling’s solution, undergoes mutarotation and can form

maltosazone (rosettes of plates or broad needles)

b) Does not reduce Barfoed’s solution.

Uses: Used as a nutrient (malt extract); and as a fermentative reagent

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