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Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)

• Sodium salt of alginic acid, a linear copolymer of -D-mannuronic acid

“major component” and -L-guluronic acid “minor component”.

Uses:

1) As thickening agent and emulsion stabilizer.

2) Alginate textile fibers are used as absorbable haemostatic dressings.

3) In biochemistry labs for immobilizing enzymes

4) Mild laxative.

2) Agar

It is the dried hydrophilic colloidal substance obtained from various red algae:

1) Gelidium, e.g., G. amansii Japan

2) Gracilaria, e.g. G. confervoides Australia
3) Pterocladia New Zealand

Collection: Algae is collected in the summers, spread on beach and bleached in

sun.

Preparation:

Seaweeds are washed with water (24 hr) and extracted with hot dilute acid,

then with water (30 hr). The hot aqueous extract is cooled then congealed in ice

machine. The agar ice block is crushed, melted, and filtered. The separated agar

is dried by dry air and powdered.

Properties:

Yellowish-white strips or coarse powder.

Swells in water, and by heating, 1% solution can be prepared which forms a stiff

jelly on cooling.

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