Red Algae
Red algae, also known as Rhodophyta, are the primary source of commercially obtained agar-agar. Agar-agar is a gelatinous substance derived from the cell walls of red algae. This seaweed is abundant in marine environments, particularly in the colder waters of the world's oceans. Red algae are known for their vibrant red or purplish coloration, which comes from the pigments phycoerythrin and phycocyanin.

Extraction Process
The process of extracting agar-agar involves boiling and purifying the seaweed to obtain the gelatinous substance. The red algae are harvested from the ocean, washed to remove impurities, and then boiled in water to release the agar-agar. The mixture is then filtered to remove any remaining debris, and the agar-agar is allowed to solidify into a gel-like substance.

Uses of Agar-Agar
Agar-agar has a wide range of applications in various industries, including food, pharmaceuticals, and cosmetics. In the food industry, agar-agar is used as a gelling agent in products such as jelly, desserts, and confectionery. It is also used as a vegetarian alternative to gelatin. In the pharmaceutical industry, agar-agar is used to make capsules and as a thickening agent in suspensions. In the cosmetics industry, agar-agar is used in skincare products for its moisturizing and emulsifying properties.

Conclusion
In conclusion, red algae are the primary source of commercially obtained agar-agar due to their abundance in marine environments and the gelatinous substance found in their cell walls. The extraction process involves boiling and purifying the seaweed to obtain agar-agar, which has a wide range of uses in various industries.