EXPERIMENT NO 01. ANALYSIS OF TRAGACANTH BY CHEMICAL TEST | PHARMACOGNOSY AND PHYTOCHEMISTRY – I PRACTICAL.

 PHARMACOGNOSY AND PHYTOCHEMISTRY – I PRACTICAL.

EXPERIMENT NO.1

Aim: Analysis of Tragacanth by chemical tests.

Reference: 1. Mayur R. Bhurat, Md. Rageeb Md. Usman, Sanjay A. Nagdev, Practical Pharmacognosy & Phytochemistry – I, Published by S. Vikas And Company (Medical Publisher) page. No. 8 – 9.

2. Dr. K.R Khandelwal, Dr. Vrunda sethi, Textbook of Practical Pharmacognosy, Pubished by Nirali Prakashan, Twenty-fifth Edition, page. No. 27.19

Requirements:

Apparatus: Test tubes, Beaker, Holder, Burner, Water bath, Tripod stand, Copper gauze etc.

Chemicals: a-naphthol, Conc.H2,SO4, Comc.HCL, Sodium hydroxide, Barium Chloride, Ferric Chloride, Copper oxide, Ammonium Hydroxide, Lead acetate, Ruthenium Red, Iodine, Potassium hydroxide , Soda lime, Fehling solution A & B.

Theory:

Biological Source: A dried exudation obtained from the stems and branches of Astragalus gummifer Labillardiere and other Asiatic species of Astragalus.

Family: Leguminosae.

Description:

Color: White to slight yellow color.

Odor: Odorless.

Taste: Mucilaginous taste.

Shape: The gum seeps from the plant in twisted ribbons or flakes that can be powdered.

Solubility: 1 g of the sample in 50 ml of water swells to form a smooth, stiff, opalescent mucilage; insoluble in ethanol and does not swell in 60% (w/v) aqueous ethanol. ”

Chemical Constituents: Tragacanthin (water soluble part), bassorin (water insoluble part), Galactouronic acid, galactopyranose, arabino-rhamnose, xylopyranose are formed from tragacanth on hydrolysis.

Uses: Demulcent, emollient, thickening agent, emulsifying agent, binding agent.

Chemical Test of Tragacanth:

Sr.No	Chemical test	Observation	Inference
A)	Preliminary Test.   1. Colour	White	Acacia, Tragacanth, Agar, Starch
	2. Odour	Odorless	Acacia, Tragacanth, Agar, Starch
	3. Taste	Mucilaginous	Agar, Acacia, Tragacanth, Starch
B)	General Test. 1. Mix small quantity with water and allow to stand	Gummy or mucilaginous nature of drugs and does not dissolve completely.	Gums & Mucilage, such as acacia, tragacanth, agar etc.
C)	Solubility in Alcohol	Soluble	Balsams, Aloes
		Insolube	Acacia, tragacanth, agar, gelatin
	Insoluble in Alcohol. 1. Triturate with water	Particles dissolved without swelling	Acacia
	2.  Mount in alcohol & irrigate with water	Particles swell and ultimately dissolve or become diffused	Tragacanth, agar, gelatin.
	3. Mount in ruthenium red	Stains pink	Agar
	4. Heat with soda lime in a dry test tube	Ammonical vapour	gelatin
	5. Boil about 1 part with 100 parts of water	Stiff jelly like mass on cooling.	Agar
	6. Warm with caustic soda (5%)	Canary yellow	Agar, tragacantt
	7. Mount in N/50 iodine	No colour reaction	Agar,
		Blue specks appears.	Tragacanth
E)	Confirmatory Test: 1. Boil with freshly prepared 10% aqueous ferric chloride solution.	Deep yellow precipitate	Tragacanth may be present
	2. Dissolve tragacanth and Precipitated copper oxide in conc. Ammonium hydroxide.	Stringy precipitate	Tragacanth may be present
	3. To 5 ml of 0.5 % w/v aqueous solution of sample, add 0.5 ml of HCL and heat for 30 minutes on water add 1.5 ml, of NaOH solution to neutralize and add Fehling’s solution A and B in equal quantities (mixed before) and warm over water bath.	Red ppt of cuprous oxide	Tragacanth may be present
	4. To 0.5 % w/v solution add 20 % w/v solution of lead acetate	Heavy flocculant white precipitate	Distinction from acacia
	5. If powder is warmed with 5% alcoholic KOH solution	Canary yellow colour	Tragacanth confirmed

Result: The given Sample of Crude drug was identified by performing the chemical test and the sample was found to be Tragacanth.