BiochemistryNajmiatul Fitria, S.Farm, M.Farm, Apt

Carbohydratesare a group of naturally occurring carbonyl compounds (aldehydes or ketones) that also contain several hydroxyl groups.

Functions:Monossacharides are fuel for celular metabolismMonosaccharides are used in several biosynthesis reactionsMonosaccharides may be converted into space-saving polysaccharides such as glycogen and starch. These molecules provide stored energy for plant and animal cells.Carbohydrates are used to form structural elements, such as chitin in animals and cellulose in plants.Important for an organisms fertilization, development, blood clotting and immune system function.

Carbohydrates include:

single sugars (monosaccharides) and their polymersoligosaccharidespolysaccharides.

Monosaccharides:Are aliphatic aldehyde with sixC atoms, five of which carry a hydroxyl group

Reactions of the monosaccharidesMutarotation, the reaction that interconverts anomers into each other.Glycoside formation, when the anomeric OH group of a sugar reacts with an alcohol, with elimination of water, it yields an Oglycoside.Reduction and oxidation,Epimerization,Esterification,

Types of monosaccharidesaldopentose (D-ribose) and aldohexoses (D-glucose)ketopentose (D-ribulose) and ketohexoses (D-fructose)deoxyaldoses acetylated amino sugarssugar alcohols (sorbitol and mannitol )

DisaccharidesWhen the anomeric hydroxyl group of one monosaccharide is bound glycosidically with one of the OH groups of another, a disaccharide is formed.

As in all glycosides, the glycosidic bond does not allow mutarotation. Since this type of bond is formed stereospecifically by enzymes in natural disaccharides, they are only found in one of the possible configurations ( a or )

Types of disaccharidesMaltose, a breakdown product of the starches contained in malt.Lactose, (milk sugar)Sucrose, sugar cane and sugar beet (cane sugar, beet sugar)

PolysaccharidesConsist of many saccharides as its monomers.

Structural polysaccharides, provide mechanical stability to cells, organs, and organisms. Waterbinding polysaccharides,are strongly hydrated and prevent cells and tissues from drying out.Reserve polysaccharides serve as carbohydrate stores that release monosaccharides as required

Important polysaccharidesMurein, in bacteriaCarbohydrates from algae (e. g., agarose and carrageenan) can also be used to produce gels.Starch, the mostimportant vegetable reserve carbohydrate and polysaccharides from plant cell walls.Chitin, is the most important structural substance in insect and crustacean shells.Glycogen, the reserve carbohydrate of higher animals, is stored in the liver and musculature in particular.