We all know starch is an important biomolecule in nature. So there is no denying fact about it. Therefore, I, Mohammad Ahsan Habib, undergraduate student of Genetic Engineering will give you a small brief about starch, its structure, characteristics, function and significance.

1. Starch
Our discussions:
―Definition
―Structure
―Characteristics
―Function
―Significance

2. What is Starch?
―A Polycarbohydrate consisting a large number of
glucose units joined by Glycosidic Bond.
― A carbohydrate reserve for plant body.
―Most important dietary source for higher animal.
― Homopolysaccharide compound.
Source : Potatoes, Wheat, Maize, Rice, Cassava.

3. Structure of Starch
Starch
Amylose
-Water soluble
-Unbranched polysaccharides
-Found (20-25%) in starch by molecular weight
-200-1000 α 1-4 linked D-glucoses monomers
-turns black-blue by reacted with iodine solution
Amylopectin
-Water insoluble
-Branched polysaccharides.
-Found (75-80%) in starch by molecular weight
-2000-200000 α 1-6 linked D-glucoses monomers
-turns red/purple by reacted with iodine solution

5. Identifying a Starch
• Colorless, odorless, tasteless, powder like biochemical
substances.
• Insoluble in Water, ether, alcohol at room
temperature.
• Assumes blue color in iodine solution.
• At high temp.
• Fehling solution is not reduced by starch.
Starch Dextrose Maltose D-Glucose

6. Function of Starch
•Remains as store food in plant body.
•Plant organelle(tubers, rhizomes) store starch for
the next growing season.
•Provide the majority of fuel for our body(store as
glycogen) .

7. Importance of starch
• Mainly taken as food.
• Used in many industries like-glucose, alcohol,
fermented alcohol production.
• Can convert into glucose to produce energy and
carbon molecules.
• Raw materials for the production of paper, glue, gum.