Microbes are the first
living creatures that have appeared on the earth. They
have flourished on the earth for at least 3.8 Ga (Ga=
109 years) of its 4.5 Ga existence. They formed the
first biosphere and continue to carry out a multitude
of essential geochemical activities that prepared the
Earth for the eventual evolution of macroscopic life.
Microorganisms are found everywhere in nature, owing
to the existence of extremophiles, and adapted to generally
hostile environments. Extremophiles abundant in deep
hydrothermal vents, sub seafloor sediments, hypersaline
lagoons, methane seeps, deserts, geysers and beneath
the surface of rocks. Some of the microbes are known
to survive longer duration in vacuum, or to be unusually
resistant to radiation. It is estimated that 50% of
the living protoplasm on this planet is microbial. Microorganisms
are the basis for the all ecosystems processes and often
well associated with themselves and higher organisms.
Due to their relationship with all plant and animal
groups and their abundance (in terms of biomass) in
virtually all habitats, man has long exploited this
metabolic wealth for food production and preservation,
management of pests and pathogens, generating biofuels,
monitoring pollutants, cleaning up of oil spills, industrial
wastewater treatment and largely used for the development
of health care applications (i.e. produce of medicinal
compounds).
Ecologically microbes are most important
for the restoration of contaminated environment. The
processes of bioremediation is an economical, versatile,
environment friendly and efficient treatment strategy,
and a rapidly developing technology to degrade and or
detoxify chemical substances such as petroleum products,
aliphatic and aromatic hydrocarbons, industrial discharges,
pesticides and their metabolites and metals. Because
of the biodiversity of microbes in nature, they can
able to degrade variety of chemical and toxic pollutants.
Hence the effects of contamination on environment can
be minimized to larger extend. Besides that they are
also the key players in the health and sustainability
of aquaculture.
Types of microorganisms
Classification
of Microorganisms – Taxonomy |
