4.1
Introduction
In the soil, microorganisms (MOs) establish the balance between organic and
inorganic substances, between living and nonliving matter. The formation of CO 2
under the action of biodegradation–mineralization of MOs is the basic stage of the
biogeochemical cycle of carbon. The carbon cycle is carried out simultaneously and
in combination with the oxygen and hydrogen cycle: by photosynthesis of green
plants from CO 2 and H 2 O organic compounds containing H which are formed and
O 2 is released; during the total decomposition of organic substances (OSs), C and H
are released by the participation of O in the form of CO 2 and H 2 O, respectively. The
cycles of the other elements (N, P, S, etc.) are also related to the C cycle.
All of the microbial species are omnivorous capable of degradation of all OSs of
biological origin. Several synthetic, xenobiotic organic compounds (nonexistent
compounds, human creations) are not biodegradable. Such compounds are
pesticides, detergents, medicines, and some plastics. They pose a great danger to
the environment by long-term pollution (Behera and Prasad 2020a).
Soil MOs play a role in soil fertility, transforming OSs into inorganic substances.
MOs also play a role in the breakdown of rocks and the formation of sulfates and
nitrates. Some of them fix atmospheric nitrogen, and others produce the necessary
CO 2 in the primary production of higher plants. MOs are widespread in nature
everywhere, with greater plasticity and adaptability than any other living organism.
The activity of MOs results in the degradation of the substrate through their vital
activity, inducing a series of biochemical transformations of their living environment
(Behera and Prasad 2020b).
The term degradation of the substrate is used since MOs use complex substances
in the substrate to make them simpler. All activity of MOs is based on biochemical
transformations, under favorable environmental conditions (temperature, pH, presence or absence of oxygen, and substrate), determined by the catalysts represented
by enzymes secreted by MOs.
All reactions to the transformation of substances through MOs are enzymatic
reactions that occur within their cell or in the environment under the action of
enzymes secreted on the substrate. For human activity, this natural activity of
MOs is important. It is represented by the decomposition of organic matter
(OM) from the soil, the rotting of natural products, etc., as well as their activity in
some polluted, anthropically degraded areas, artificial arrangements, and industrial
premises.
In nature, MOs live in complex biocenoses along with other types of living
creatures in complex interrelations whose knowledge is important for the proper
control and use of these processes in practical applications.
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M. Butu et al.
Introduction
In the soil, microorganisms (MOs) establish the balance between organic and
inorganic substances, between living and nonliving matter. The formation of CO 2
under the action of biodegradation–mineralization of MOs is the basic stage of the
biogeochemical cycle of carbon. The carbon cycle is carried out simultaneously and
in combination with the oxygen and hydrogen cycle: by photosynthesis of green
plants from CO 2 and H 2 O organic compounds containing H which are formed and
O 2 is released; during the total decomposition of organic substances (OSs), C and H
are released by the participation of O in the form of CO 2 and H 2 O, respectively. The
cycles of the other elements (N, P, S, etc.) are also related to the C cycle.
All of the microbial species are omnivorous capable of degradation of all OSs of
biological origin. Several synthetic, xenobiotic organic compounds (nonexistent
compounds, human creations) are not biodegradable. Such compounds are
pesticides, detergents, medicines, and some plastics. They pose a great danger to
the environment by long-term pollution (Behera and Prasad 2020a).
Soil MOs play a role in soil fertility, transforming OSs into inorganic substances.
MOs also play a role in the breakdown of rocks and the formation of sulfates and
nitrates. Some of them fix atmospheric nitrogen, and others produce the necessary
CO 2 in the primary production of higher plants. MOs are widespread in nature
everywhere, with greater plasticity and adaptability than any other living organism.
The activity of MOs results in the degradation of the substrate through their vital
activity, inducing a series of biochemical transformations of their living environment
(Behera and Prasad 2020b).
The term degradation of the substrate is used since MOs use complex substances
in the substrate to make them simpler. All activity of MOs is based on biochemical
transformations, under favorable environmental conditions (temperature, pH, presence or absence of oxygen, and substrate), determined by the catalysts represented
by enzymes secreted by MOs.
All reactions to the transformation of substances through MOs are enzymatic
reactions that occur within their cell or in the environment under the action of
enzymes secreted on the substrate. For human activity, this natural activity of
MOs is important. It is represented by the decomposition of organic matter
(OM) from the soil, the rotting of natural products, etc., as well as their activity in
some polluted, anthropically degraded areas, artificial arrangements, and industrial
premises.
In nature, MOs live in complex biocenoses along with other types of living
creatures in complex interrelations whose knowledge is important for the proper
control and use of these processes in practical applications.
82
M. Butu et al.