Microbes in Human Welfare
Beneficial Microbes: Household, Industrial and Sewage
Microbes are those living beings which are generally unicellular and are visible only under a microscope.
Microbes cause a large number ofdiseases in human beings, plants and animals. But not allmicrobes are pathogenic. Several microbes are useful to man in diverse ways.
Micro-organisms such as Lactobacillus and others commonly called lactic acid bacteria (LAB) are used to make curd from milk.
In baking industries, baker’s yeast or Saccharomyces cerevisiae is used for making breads. Certain dishes such as idliand dosa are made from dough fermented by microbes.
A number of traditional drinks like cider, toddy etc. are made by fermentation by microbes.
Microbes are also used for fermentation of fish, soyabean and bamboo shoots.
In cheese industries, certain Bacteria and fungi are used to impart particular texture, taste and flavor to cheese.
Microbes are used to synthesise a number of industrial products like lactic acid, acetic acid which are valuable to human beings.
Microbes especially yeasts have been used for the production of beverageslike wine, beer, whisky, brandy, etc.by the process of fermentation.
Antibiotics like penicillin are also produced by useful microbes.
Microbes are used for the production of enzymes like lipase, pectinase and streptokinase.
Microbes arealso being usedto treat sewage (waste water) by the process of activated sludge formation.
Beneficial Microbes: Biogas, Biocontrol and Biofertiliser
Biogas is a mixture of methane and carbon dioxide.
It is produced by anaerobic breakdown of organic matter by the bacteria known as methanogens, exampleMethanobacterium.
Biogas is an effective fuel for cooking, electricity production and water heating.
Biocontrol is the practice of using natural enemies of pests for destroying them.
An organism that is used to control a pest is called a biocontrol agent.
Several microorganisms are used as biocontrol agents.
Biocontrol methods use fungal herbicides, bacterial insecticides and entomopathogenic fungi to control pests.
The bacterium Bacillus thuringiensis (Bt) kills large number of insects like moths and aphids, and it is used as an insecticide.
Entomopathogenic fungi like Hirsutellathompsonii kill their host insects after growing in them.
GM crops have been developed with insect- resistant Bt genes incorporated in them.
Chemical fertilisers have considerably deteriorated our environment and caused environmental pollution.
So,biofertilisers are used to add nutrient to the soil.
Biofertilisers include the use of various microorganisms like bacteria (Rhizobium, Azotobacter), fungi and cyanobacteria (Aulosira, Nostoc, Oscillatoria) to increase soil fertility.