knowledge mind: algae:economic importance

algae:economic importance

Algae are important in the field of agriculture and industry in addition used as food, fodder and manure.

Algae are important as a source of food in some coastal parts of the world.
In the pacific islands the red,brown and green algae form a regular portion of diet.
In india spirogyra and oedogonium are dried and used in soup preparations.
In Europe ulva is used for soup preparation.
The colonies of nostoc are boiled and used as food in brazil.
Porphyra a red algae is considered a taste ful dish in England and it is common diet in korea,japan and china.
It is rich in vitamin b and c.
Seaweeds like porphyra tenera(red alga) and laminaria(brown alga) are consumed by the coastal people of china and japan.
Caulerpa racemosa(green alga) is cultivated in Philippines as a source of food in japan about 25% of the daily diet consists of seaweeds.

In Norway,france,usa,Denmark and new Zealand,seaweeds are used as fodder for animals.
In great Britain,france,Scandinavia and pacific coasts of usa,kelps are chopped for sheep and chicken.
Some countries have even developed small industries for processing the weeds such as ascophyllum,focus and laminaria into suitable cattle feed.
The processed food is given to cattle,poultry and pigs. A red alga rhodymenia is used as a cattle fodder in france.

Algae are useful as a source of many commercial products.
The major products commonly derived from them are 1)agar agar,2)carrageenin,3)alginic acid and 4)diatomite

1)agar agar:

It is mucilage produced by certain red algae and stored with cellulose in the cell wall.
Main sources of agar aaagar are:gelidium,gracilaria,gigartina
Other sources of agar agar are camphylaephora,hypnea,furcellaria
Agar agar is a gelatinous,clear,nitrogen free extract from the above mentioned genera of red algae.
This extract is a solid which melts between90 to 100 f at lower temperature it changes back to a solid.
Uses:preparation of foodstuffs.
Forms a base for culture media for bacteria,fungi,algae and other tissues.
Preparation of certain medicines,cosmetics,leather and textile industry

2)alginic acid:

Algin is a carbohydrate which occurs in the middle lamella and primary walls of a few seaweeds.
The soluble calcium of alginic acid is known as algin.
The insoluble extract is alginic acid.
The salts of alginic acid found in the cell walls of the algae are called alginates
Sources:ascophyllum,laminaria,lessonia,macrocystis
Uses:used as thickness in food industry cosmetics and textile industry
Used in preparing plastics and artificial fibers
Also used in rubber industry
They are of great value as emulsifiers,as gelling agents of confectionaries,paints and ice creams.

3)carrageenin:

it is cell wall polysaccharide and is a mucilaginous extract.
Source:a red alga chondrus crispus
Uses:in food,textiles,pharmaceuticals,leather and brewing industry used as a component of toothpastes,deodorants,cosmetics and paints.

4)diatomite/kkieselguhr:

it is a rock like deposit formed from the indestructible siliceous frustules of the the past diatoms that had collected over many millions of years on the floor of the sea to form organic sediments.
These diatomaceous earth which is put to several commercial uses.
Property:it is a white substance firm but usually soft and light.
It is highly porous and insoluble.
It has abrasive qualities,is chemically inert and is fire proof.
Uses:used as filters for oils and other solutions in industry
Used in insulations of refrigerators,boilers,hot and cold popes.
Sound proof rooms and in furnaces.
Used in polishes for metals.
Used in manufacture of dynamite.
Used as a constituent of some tooth powder and bleaching powders.

the seaweeds,mostly brown and red algae are used as organic fertilizers
They are richer in potassium but poor in nitrogen and phosphorus than the farm manureturbinaria is used as a fertilizer around palm trees.
Concentrated liquid extracts of sea weeds are sold as liquid fertilizers as also insecticides.
The seaweed products aid in binding sandy soils ass well as in the breakdown of clayey soils.

Many seaweeds contain a high percentage of iodine contents and are thus used in the preparation of various goitea medicines.
Chlorellin an antibiotic is obtained from chlorella.
Agar agar forms the basis of many medicines used as laxatives.
Carrageenin extract acts as a blood coagulant.

Sewage consists of many domestic and industrial wastes.
It contain many organic and inorganic constituents in dissolved or suspended stage.
The disposal of this sewage is mainly an aerobic process and this oxygenation is facilitated mainly by some algae e.g. chlamydomonas,chlorella,euglena,scenedesmus etc.
The aeration of sewage is essential,especially in smaller sewage bodies or ponds to avoid unpleasant odour.

Soil conservation is effected by algae to a great extent.
After rains,the members of chlorphyceae develop and check soil erosion on disturbed on burned soils.

Algae grow luxuriantly in water.
Reservoirs meant for domestic water supplies.
They produce bad tastes in drinking water and also interfere with the filtration process of water.
Common algae found in reservoirs of water supply are chlamydomonas,volvox etc.