The document provides a comprehensive profile of agar, highlighting its biological source from red algae, geographical locations for collection, and its preparation process. It details the chemical constituents, including agarose and agaropectin, and includes various chemical tests for identification and quality assessment of agar. Additionally, the document discusses common adulterants and diverse applications of agar in fields such as pharmaceuticals, microbiology, and food industry.

1. Drug profile of AGAR
PHARMACOGNOSY AND PHYTOCHEMISTRY -I
Unit V
Primary metabolites : Carbohydrates.
Prepared By ,
GORE AVINASH BHARAT
B Pharm. 2nd yr
Roll no. 15
GUIDE : Mr. S.V. GARAD SIR

2. AGAR
❖ SYNONYMS :
➢ Agar agar
➢ Japanese Isinglass
➢ Vegetable Gelatin
❖ FAMILY :
➢ Gelidiaceae
➢ Rhodophyceae (for Red algae)

3. ❖Biological Source
Agar is the Gelatinous substance obtained from :
➢ Red algae like Gracilaria and Pterocladia.
➢ Gelidium Species (like amansii Lamouroux, pristoidesTurn Kiitz)
❖ GEOGRAPHICAL SOURCE :
Japan,Korea ,South Africa,U.S.A., China,India, Australia

6. ❖MORPHOLOGY & MACROSCOPIC
CHARACTERS

7. MORPHOLOGY & MACROSCOPIC CHARACTERS
Colour Yellowish white to gray or Colourless
Odour Odourless
Taste Mucilaginous
Shape Strips,Flakes or Course powder
Size Strips are about 60 cm in length and 4 mm
wide.
Wide sheets are 50 -60 cm long and 10-15
cm wide.
Solubility Insoluble in organic solvents,cold water.
Soluble in hot water and forms a gelatinous
solution after colling hot solution.

8. ❖ CULTIVATION COLLECTION AND
PREPARATION

9. CULTIVATION COLLECTION AND PREPARATION

10. CULTIVATION COLLECTION AND PREPARATION
➢ The algae are collected from May to October in Japan and
manufacturing of Agar is done in winter.
➢ The red algae are grown in the sea,on the support of poles
on,which they develop.
➢ These poles are withdrawn, algae is removed,dried,beaten and
shaken to remove shell and sand.
➢ The algae are bleached by exposure to sunlight or washing with
water.
➢ The washing with water removes the associated salts. Then these
are boiled with acidulated water (one part algae with 55-60 parts
water)for few hours.
➢ Mucilaginous mass is filtered while hot then cooled. The jelly is
formed and cut into bars.
➢ These bars are forced through wire netting and strips are formed.
➢ These are dried in sunlight and freezing and thawing remove
moisture.Finally, agar is dried at 35°C.

11. CULTIVATION COLLECTION AND PREPARATION
GELIDIUM
/GRACILARIA
SUN BLEACHING
HOT EXTRACTION
FILTERATION &
GELLING
NATURAL
FREEZING
WASHING
(DIFFUSION)
THAWING &
DRYING
HYDRAULIC PRESSURE
DRYING CHAMBER
MILLING
AGAR
POWDER
STRIP
/SQARE
AGAR

12. CULTIVATION COLLECTION AND PREPARATION

13. CULTIVATION COLLECTION AND PREPARATION

14. ❖CHEMICAL CONSTITUENTS
Contains two different polysaccharides
➢AGAROSE
• Responsible for the gel property of agar
• Consists of D-galactose and L-galactose unit.
➢ AGAROPECTIN
➢ Responsible for the viscosity of agar solution.
➢ Structure is not known but it believed that it may consist of
sulphonated polysacchride.

15. ❖CHEMICAL TESTS
➢Boil about 1.5 gm agar with 1oo ml of water .Cool the
solution to room temperature.It forms a stiffy jelly.
➢Sample + KOH Canary yellow colour agar
➢Ash of agar is treated with dil.HCL.this on microscopic
examination shows Fragments of Diatoms.
➢Sample +N/50 Iodine Deep crimson to Brown
colour.
➢Positive to Fehling’s solution test.
➢Positive test with Molisch reagent.
➢To agar powder a solution of Ruthenium red is
added.Red colour is formed indicating mucilage.

16. CHEMICAL TESTS
➢ Sample + soda lime NaNH3 is produced
➢ Sample + Million’s reagent No Ppt.
➢ Sample + Tannic acid No Ppt.
➢ It has a swelling index of not less than 10.
❖ADULTERENTS:
 Some of the common adulterants present in agar are
➢Gelatin
The presence of gelatin can be detected by addition of
equal volume of 1% trinitrophenol and 1% of agar
solution; the solution produces turbidity or precipitation.

17. ADULTERENTS:

18. ADULTERENTS:
➢DANISH AGAR
Danish agar has an ash of 16.5–18.5%, it is formed from
Rhodophyceae indigenous to the Denmark costal
region.The Danish agar has a gel strength which is half of its
gel strength of Japanese agar
➢STARCH
The powdered drug is adulterated with starch. Mount the
drug in chloral-iodine solution and observe the starch
grains.

19. ❖USES

20. USES
➢As a Bulk Laxative and in chronic constipation
➢In the preparation of Vaginal capsules and
Suppositories.
➢To prepare nutrient media in Bacteriological Culture.
➢It is used as an Emulsifying agent.
➢Used in Affinity Chromatography.
➢The gels of pure Agarose are used for the
Electrophoresis of proteins.

21. THANK
YOU...