At present, the world is reeling under the problem of different environmental
pollutions, viz., soil, water, and air pollution, as a result of anthropogenic activities,
intensive inorganic agriculture, industrial revolution releasing a wide array of
xenobiotics. Across the world, scientists are trying to overcome pollution through
physical, chemical, and thermal processes. The major drawbacks of these methods
include their labor-intensive nature, high cost, and undesirable changes in the treated
soil's physical, chemical and biological characteristics. The only alternative solution to
overcome this challenge is microorganisms. The microorganisms transform the various
substances through their metabolic activity. It mainly depends on two processes.
growth and cometabolism. Growth refers to the process which results in complete
degradation (mineralization) of organic pollutants. Hence, the only source of carbon
and energy in growth is an organic pollutant.
On the other hand, cometabolism refers to the process in which the metabolism of an
organic compound takes place in the presence of a growth substrate, which is used as
the primary source of carbon and energy. For maintaining the global carbon cycle and
renewing our environment, microorganisms have an essential role to play. The various
microbial activities are comprehended in biodegradation, bioremediation, and
biotransformation. Substances transformed by microorganisms include a wide range of
synthetic compounds and other chemical substances like hydrocarbons and heavy
metals, which have toxic ecological effects. However, in most cases, this statement is
concerned with the potential degradabilities of microorganisms estimated under ideal
growth conditions using selected laboratory cultures.