Q. What is the commercial importance of algae?

Numerous algae have high nutritional value and are commercialized and consumed as human food they are very popular food in the oriental world. Jelly compounds are extracted from some algae like pastes and glues for industrial and commercial use.

The agar-agar, used as a medium for biological culture in medicines and in laboratories, and the substance known as carrageenin, a component of tooth pastes, cosmetics, hygienic products and paint, are extracted from rhodophyte algae. Diatom algae deposited on the bottom of the sea form diatomites, used in the production of, refractories, filters thermal isolation and cement some algae are used as agricultural fertilizers.