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

Carbohydrate Introduction

Definition:

Carbohydrate are naturally occurring compounds of carbon,

hydrogen and oxygen, in which the ratio of the number of atoms of hydrogen

to those of oxygen in the molecule is the same as in the molecule of water

“H2O, 2 : 1”.

The molecular formula of carbohydrate can therefore be written C x(H 2O) x,

but not every compound written in this form is a carbohydrate (e.g. acetic acid,

CH 3COOH or C 2(H 2O) 2, is not a carbohydrate). On the other hand, there are

several true sugars which do not possess the required formula or ratio of H: O, for

example the deoxy sugar such as: rhamnose (C 6H 12O 5), digitoxose (C 6H 12O 4),

cymarose (C 7H 17O 4); amino sugars and uronic acids), but they are covered by the

definition and retain the sugars in their structure and properties.

Carbohydrates can be also described as polyhydroxy aldehydes,

polyhydroxy ketones or compounds that can be hydrolyzed to them.
The term “Carbohydrates” is still in use beside the equivalent name

“Saccharide”, which is derived from the Latin word of sugar “Saccharum” as the

simple members at the family carbohydrate have sweet taste.

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