You must have seen algae kids. Whenever you come across a body of water, take note to observe carefully the green strands swimming around. They are what we call as algae. They are lower plants and unlike the huge trees, have a simple body structure. But don’t underestimate these tiny plants as they are highly useful.
Algae have been used since ages for a variety of applications. Let’s look at some of their main uses.
1. Agar Agar: Agar is a mucilage produced mainly by red algae. It is used as a culture media for bacteria in laboratories, and also to prepare medicines and cosmetics. It s a gel like substance. Algal species that serve as sources of Agar Agar- Gelidium, Gracillaria and Gigartina.
2.Alginic Acid: It is a carbohydrate which is obtained from cell walls of weeds. Used mainly in manufacture of plastic and artificial fibre. Also as a thickener in food industry, cosmetics etc. Also used in Rubber industry. Algal species that serve as sources of Alginic acid- Ascophyllum, Laminaria, Lessonia, Macrocystis.
3. Carrageenin: It is again a cell wall polysaccharide and is a mucilage kind of product. Used in cough remedies, food, textile, leather and brewing, toothpastes, deodorants and paints. Algal species that serve as source of Carrageenin- Chondrus crispus (a red alga).
4. Diatomite: It is a rock like deposit formed from cell walls of diatoms. It is fire proof. Used as a filter for oil, solvents, insulation of refrigerators, boilers, hot and cold pipes, silver polish base, wine and paper industry.
5. Glue from Algae- Glue obtained is called as funori. Species- Gleopeltis furcata.
6. Iodine from Algae- Laminaria, Fucus, Eklonia and Eisenia.
7. Bromine from Algae- Rhodomela and Polysiphonia.
8. Algae in Agriculture- Blue green algae can fix nitrogen. Examples- Anabaena, Oscillatoria princeps, Oscillatoria formosa, Spirulina, Nostoc, Cylindrospermum. Used a s a fertilizer in rice fields. Sometimes algae can also help to reclaim alkaline soils.
9. Algae in Medicine-Chlorellin obtained from Chlorella (an antibiotic). Carrageenin extract is used as a blood coagulant. Laminaria species because of their high iodine content are used in making goitre medicines.
10. Algae as food- Yes, who would have thought that these slimy looking atrocious creatures can be eaten. Not so much in India but if you go to Europe or Japan, you can eat these algae and they taste good too.
Nostoc– in Brazil
Laminaria– (Kombu) in Japan
Porphyra– (Laver) in England
So next time you see the algae, remember, it is not just a weed but also provides many useful products.