Carbohydrates are polyhydroxy aldehyde or ketone compounds that contain at least 3 carbon atoms and a carbonyl functional group that is either an aldehyde or keto group. They are defined as compounds that yield these derivatives upon hydrolysis. Carbohydrates serve important biomedical roles as the chief source of energy, constituents of lipids and proteins, and degradation products that act as promoters or catalysts. Inherited deficiencies in carbohydrate metabolic pathways can cause diseases like galactosemia and glycogen storage diseases.

1. CHEMISTRY OF
BIOMOLECULE
S
CARBOHYDRATE
S

2. CARBOHYDRATES
Definition: Carbohydrates are defined chemically as
 Aldehyde or ketone derivatives of the higher polyhydric alcohols, or
compounds which yield these derivatives on hydrolysis.
 Polyhydroxy aldehyde or ketone compounds which produce them on
hydrolysis are called as carbohydrates.
 carbohydrates are polyhydroxy compounds with at least 3 carbon atoms,
essentially containing potentially active carbonyl carbon either that of
aldehyde and ketone.
 Polyhydroxy compounds (poly-alcohols) that contain a carbonyl (C=O)
group.

3. CHEMICAL DEFINITION OF CARBOHYDRATES
Polyhydroxyl: Having more than one hydroxyl group. (-OH)
Functional Group: It is a specific group of atoms or bonds which
are part of a larger hydrocarbon chain.(Provide a specific
chemical behaviour).
For carbohydrates, the functional group is the carbonyl group
which may be either
Aldehyde Group (H-C=O)
Or
Keto Group (C=O)

5. Biomedical Importance of Carbohydrates
• Chief source of energy.
• Constituents of compound lipids and conjugated proteins.
• Degradation products act as “promoters” or ‘catalysts’.
• Certain carbohydrate derivatives are used as drugs like cardiac glycosides/antibiotics.
• Lactose principal sugar of milk—in lactating mammary gland.
• Degradation products utilized for synthesis of other substances such as fatty acids, cholesterol,
amino acid, etc.
• Constituents of mucopolysaccharides which form the ground substance of mesenchymal tissues.
 Inherited deficiency of certain enzymes in metabolic pathways of different carbohydrates can
cause diseases, e.g. galactosemia, glycogen storage diseases (GSDs), lactose intolerance, etc.
 Derangement of glucose metabolism is seen in diabetes mellitus.