Principles of Biochemistry (2+1)

3.3.4.1 Agar

Agar is a polymer made up of subunits of the sugar galactose .The word agar comes from the Malay word agar-agar (meaning jelly). It is also known as kanten or agal-agal (Ceylon agar).

Structure: It is an unbranched polysaccharide obtained from the cell walls of some species of red algae or seaweed. Agar polysaccharides serve as the primary structural support for the algae's cell walls.

Uses: Gracilaria, Gelidium, Pterocladia and other red algae are used in the manufacture of the all-important agar. Agar can be used as a vegetarian gelatin substitute, a thickener for soups, in jellies, ice cream and desserts, as a clarifying agent in brewing, a laxative and for paper sizing fabrics. It is used widely as a growth medium for microorganisms and for microbiological and biotechnological applications.