Osazone Test- Definition, Principle, Procedure, Result, Uses


Osazone test is a chemical test that is used to detect and differentiate reducing sugars from non-reducing sugars. Reducing sugars are carbohydrates that can reduce other compounds by donating electrons or hydrogen atoms. Non-reducing sugars are carbohydrates that cannot do so. Examples of reducing sugars are glucose, fructose, lactose, maltose, etc. Examples of non-reducing sugars are sucrose, trehalose, etc.

Osazone test is based on the reaction of reducing sugars with phenylhydrazine, a chemical compound that contains nitrogen and hydrogen atoms. Phenylhydrazine reacts with the carbonyl group (C=O) of the reducing sugar and forms a yellow-colored crystalline compound called osazone. Osazone has a characteristic shape, solubility, melting point, and time of formation that can be used to identify the type of reducing sugar.

Osazone test is also known as phenylhydrazine test because phenylhydrazine is the main reagent used in this test. Osazone test was first developed by German chemist Emil Fischer in 1884. He used this test to determine the structure and configuration of different sugars.

Osazone test is a simple and inexpensive test that can be performed in a laboratory with basic equipment and materials. Osazone test can be used for various purposes such as identifying unknown sugars, locating sugars in plant tissues, studying the metabolism of sugars, etc. Osazone test is one of the oldest and most widely used tests for carbohydrate analysis.