Page 151 - Pharmacognosy-II (06-PG 303)

Constituents:
• Agarose: neutral jelling fraction composed of alternating galactose and 3,6
anhydrogalactose.
• Agaropectin: non jelling fraction but affects the viscosity of the solution,
composed of uronic acid, partially esterified with sulphuric acid.

Chemical tests:
• Positive Molish’s.
• Powder gives crimson red colour with N/50 iodine solution.
• Boil with dil. HCl and filter

a. Examine the residue under microscope (diatoms and sponge spicule)
b. On the filtrate carry out the following tests:

• Fehling’s: positive reduction.
• Add few drops of BaCl2 a white ppt is formed.
Uses:

1.Suspending,thickening and emulsifying agent in pharmacy.
2.Bulk laxative.
3. Nutrient media in bacteriological cultures.
4. Agarose is used for Electrophoresis, affinity and gel filteration
chromatography.

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