Title: - A marine Source Purified Carbohydrates Description: In this video the viewers will come to know about Sodium Alginate that is one of the carbohydrates containing crud drugs obtained from the algal growth of the species of family Phaeophyceae. This drug becomes important since it is obtained from marine source. Here the synonyms, biological sources (scientific names & Family), geographical sources (what are the ocean & countries where it can be collected), chemical constituents, identification tests and uses has been discussed in brief. Portion explained: 1. Synonyms of Sodium Alginate 2. Biological Sources of Sodium Alginate 3. Geographical Sources of Sodium Alginate 4. Collection of Sodium Alginate 5. Description of Sodium Alginate 6. Chemical Constituents of Sodium Alginate 7. Chemical Test of Sodium Alginate 8. Uses of Sodium Alginate

1. SODIUM ALGINATE
BY
Dr. Jitendra Patel
Associate Professor
AIPS, Hyderabad, India.

3. Synonyms
1. Algin,
2. Alginic acid sodium salt,
3. Sodium polymannuronate,
4. Kelgin,
5. Minus,
6. Protanal.

4. Biological Source
• Sodium alginate is the sodium salt of alginic acid.
• Alginic acid is a polyuronic acid composed of
reduced mannuronic and glucoronic acids, which
are obtained from the algal growth of the species
of family Phaeophyceae.
• The common species are Macrocystis pyrifera,
Laminaria hyperborea, Laminaria digitata,
Ascophyllum nodosum and Durvillaea lessonia.
• It is a purified carbohydrate extracted from
brown seaweed (algae) by treatment of dilute
alkali.

5. Geographical Source
• Sea-weeds are found in Atlantic and Pacific
oceans, particularly in coastal lines of Japan,
United States, Canada, Australia and
Scotland. In India, it is found near the coast of
Saurashtra. The largest production of algin is
in United States and U.K.

6. Collection and Preparation
• The brown coloured algae are
used for extraction of alginic
acid. The colour is due to
carotenoid pigment present in
it. M. pyrifera, the principal
source for global supply, is a
perennial plant that lives from 8
to 12 years, and grows, as much
as, 30 cm per day. This giant
kelp is found mainly in Pacific
Ocean. It grows on stands from
15 m to 1.5 km in width and
several km in length. The
mechanical harvesting is done
about four times a year.

7. • Alginic acid is present in the cell wall.
• The seaweeds are harvested, dried,
milled and extracted with dilute
sodium carbonate solution which
results in a pasty mass.
• It is then diluted to separate insoluble
matter. Soft water is only used for
extraction purposes, so as to avoid
incompatibilities.
• It is treated with calcium chloride or
sulphuric acid for conversion into
either calcium alginate or insoluble
alginic acid, which is collected and
purified by thorough washing.
• If calcium is used, it is treated with
hydrochloric acid. Alginic acid so
collected is treated with sodium
carbonate for neutralization and
converted into sodium salt.
• The alginic acid content on dry solid
basis varies from 22% to 35% in all the
varieties of brown algae.

8. Description
Colour White to buff coloured powder
Odour Odourless
Taste Tasteless
Appearance It is available either as a coarse or fi ne powder.
It is readily soluble in water forming viscous
colloidal solution and insoluble in alcohol, ether,
chloroform and strong acids. 1% solution of gum
at 20°C may have a viscosity in the range of 20–
400 centipoises.

9. Identification Tests
1. Precipitate formation with Calcium chloride To a
0.5% solution of the sample in sodium hydroxide, add
one-fifth of its volume of a 2.5% solution of calcium
chloride. A voluminous, gelatinous precipitate is
formed. This test distinguishes sodium alginate from
gum arabic, sodium carboxymethyl cellulose,
carrageenan, gelatin, gum ghatti, karaya gum and
tragacanth gum.
2. Precipitate formation with Ammonium sulphate To a
0.5% solution of the sample in sodium hydroxide, add
one-half of its volume of a saturated solution of
ammonium sulphate. No precipitate is formed. This
test distinguishes sodium alginate from agar, sodium
carboxymethyl cellulose, carrageenan, methyl cellulose
and starch.

10. 3. Test for alginate
Moisten 1–5 mg of the sample with water and
add 1 ml of acid ferric sulphate. Within 5 min,
a cherry-red colour develops that finally
becomes deep purple.
4. 1% solution in water forms heavy gelatinous
precipitate with dilute sulphuric acid.

11. Chemical constituents
• Algin consists chiefly of the sodium salt of alginic
acid, a linear polymer of L-guluronic acid and D-
mannuronic acid; the chain length is long and
varies (mol. wt. from 35,000 to 1.5 × 106) with
the method of isolation and the source of the
algae.
• Mannuronic acid is the major component.. The
alginic acid molecule appears to be a copolymer
of 1, 4-linked mannopyranosyluronic acid units,
of 1, 4-linked gulopyranosyluronic acid units,
and of segments where these uronic acids
alternate with 1, 4-linkages.

12. Uses
• High and medium viscosity grades of sodium alginate
are used in the preparation of paste, creams and for
thickening and stabilizing emulsions.
• It is a good suspending and thickening agent, but a
poor emulsifying agent.
• It is used as binding and disintegrating agent in tablets
and lozenges.
• In food industry, it is used for the preparation of jellies,
ice cream, etc. It is also used in textile industry.
• For pharmaceutical purposes, when desired, it is
sterilized by heating in an autoclave.
• The solution of sodium alginate should not be stored in
metal containers.
• It is preserved by the addition of 0.1% of chloroxylenol,
chlorocresol, benzoic acid or parabenes.
• Potassium, aluminium and calcium alginates are also
used medicinally.

13. • Capsules containing sodium alginate and
calcium carbonate are used to protect
inflamed areas near the entrance to the
stomach.
• The acidity of the stomach causes formation
of insoluble alginic acid and carbon dioxide;
the alginic acid rises to the top of the stomach
contents and forms a protective layer.

14. Thank You