Test for carbohydrates, qualitative test of carbohydrates, identification test of carbohydrates, carbohydrates test , carbohydrates by Raj kumar, qualitative test of carbohydrates for students

1. By Raj Kumar Kumawat (B.Pharm)
Bharti Pharmacy College

2. CARBOHYDRATE MIXTURE
MOLISCH TEST (Common test for carbohydrates)Positive
Carbohydrates
IODINE TEST
Positive(+ve) Negative (- ve)
Starch, Dextrin
(Blue purple )
Glucose, fructose, maltose, sucrose
BENEDICT TEST+ve - ve
Reducing Sugar Non Reducing Sugar
Sucrose
Barfoed Test
+ ve - ve
Monosaccharides
Glucose and fructose
Disaccharides
Maltose and lactose
OSAZONE TEST
Sunflower Crystals- Maltose
&
Puff shaped Crystals- Lactose
SELIVANOFF’S TESTPPT
Fructose Glucose
Needle shaped crystals with Osazone
test
*PPT means presipitate

3.  Procedure: In test tube 1- 2 ml solution of carbohydrate is
mixed with molisch reagent .
 Molisch’s reagent:- 10% alcoholic solution of α- napthol.
 About 1 ml of concentrated Sulphuric acid is added along
with the side of tube.
 Result: Purple colour gives the confirmation of
carbohydrates.

4.  Procedure: Carbohydrate mixture
treated with iodine solution.
 Result: Blue colour gives the
confirmation of polysaccharides.

5.  Procedure: Carbohydrates mixture treated with
Benedict’s reagent.
 Benedict’s reagent:- Copper sulphate solution.
 Result: Green colour gives the confirmation of
reducing sugars.
 Reducing sugars: Glucose, Fructose, Maltose,
Lactose

6.  Procedure: Carbohydrates mixture treated with
Barfoed’s reagent.
 Barfoed’s reagent:- Copper sulphate and
Acetic acid solution.
 Result: Red colour gives the confirmation of
mono & disaccharides.

7.  Procedure: Carbohydrates mixture treated with
phenyl hydrazine and acetic acid solution.
 Result: Crystals formation.
 Sun flower shaped crystals- Maltose
 Puff shaped crystals- Lactose
 Needle shaped crystals- Glucose and Fructose
 Reducing sugars: Glucose, Fructose, Maltose,
Lactose

8.  Procedure: Carbohydrates mixture treated with
seliwanoff’s reagent.
 Seliwanoff’s reagent:- Resorcinol crystals with
concentrated hydrochloric acid.
 Result: Precipitate gives the confirmation of fructose
(ketose sugar) & no precipitation gives the
confirmation of glucose (aldehyde sugar) .

9.  Procedure: Carbohydrates mixture treated with Fehling
solution A & B.
 Fehling solution A:- Solution of copper sulphate
 Fehling solution B:- Potassium sodium tartrate
(Rochelle salt)
 Result: Brownish red colour gives the confirmation of
reducing sugars.
 Reducing sugars: Glucose, Fructose, Maltose, Lactose

10.  Procedure: Carbohydrates mixture treated with Tollen’s
reagent and add ammonium hydroxide drop.
 Tollen’s reagent:- A solution of Silver nitrate (AgNO3)
and Ammonia(NH3).
 Result: Silver colour gives the confirmation of reducing
sugars.
 Reducing sugars: Glucose, Fructose, Maltose, Lactose

11. THANKS