study provides strong support for the concept that microorganisms use different sets
of genes for the utilization of the petroleum hydrocarbons depending on its concentration in its environment (Wang et al. 2019b).
The downregulation of several chemotaxis related proteins at high concentrations
of crude oil may indicate that, at these concentrations, chemotaxis may be inhibited
in P. aeruginosa, although at lower concentrations, it uses chemotaxis to locate the
hydrocarbon molecules. The concentration of hemolysin (UniProt ID: W1MWQ1), a
bio-emulsifier produced by P. aeruginosa was also found to increase >3-fold at the
higher concentration of crude oil (Wang et al. 2019b).
11.7 Strategies for Bioremediation
Bioremediation is a process whereby biological degradation processes are utilized to
eliminate, attenuate, or transform organic contaminant and pollutants to mainly
carbon dioxide, water, and biomass, in order to mitigate risks (Ite and Ibok 2019).
Microbial bioremediation represents the most “eco-sensible” strategy for the
removal of petroleum hydrocarbon contamination, being the most economical
mechanism as well as the method which causes the least damage to the ecosystem.
It is therefore considered an environmentally sustainable “green” approach for
tackling oil pollution.
Bioremediation strategies may be carried out in situ (decontamination process is
effected at the site of contamination) or ex situ (contaminated material is removed
from the original position to a treatment plant, on site or at another location).
11.7.1 Use of Microbial Consortia
As individual bacterial species or strains often do not have the required genetic/
metabolic diversity to degrade the entire spectrum of components in crude oil, the
general strategy is to use microbial consortia comprising several different species, or
mixed consortia of bacteria and fungi, to achieve complete degradation. It has been
proposed that microbial consortia used in bioremediation efforts should be tailored
to suit the particular condition of the contaminated site as well as the polluting
hydrocarbon classes. Such a strategy may also require the introduction of different
microbial consortia at different stages of the remediation process to ensure complete
removal of hydrocarbon contaminants (Truskewycz et al. 2019).
Knowledge of the microbes’ capacities for biodegradation and the interaction
between the organisms is important for developing optimally functioning bioremediation systems. In microbial communities, individual species may interact with each
other in a synergistic relationship that produces a cocktail of bioactive compounds,
which may include oxidative and hydrolytic enzymes that have been implicated in
processing of various hydrocarbon fractions. Perera et al. (2019) reported a naturally
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of genes for the utilization of the petroleum hydrocarbons depending on its concentration in its environment (Wang et al. 2019b).
The downregulation of several chemotaxis related proteins at high concentrations
of crude oil may indicate that, at these concentrations, chemotaxis may be inhibited
in P. aeruginosa, although at lower concentrations, it uses chemotaxis to locate the
hydrocarbon molecules. The concentration of hemolysin (UniProt ID: W1MWQ1), a
bio-emulsifier produced by P. aeruginosa was also found to increase >3-fold at the
higher concentration of crude oil (Wang et al. 2019b).
11.7 Strategies for Bioremediation
Bioremediation is a process whereby biological degradation processes are utilized to
eliminate, attenuate, or transform organic contaminant and pollutants to mainly
carbon dioxide, water, and biomass, in order to mitigate risks (Ite and Ibok 2019).
Microbial bioremediation represents the most “eco-sensible” strategy for the
removal of petroleum hydrocarbon contamination, being the most economical
mechanism as well as the method which causes the least damage to the ecosystem.
It is therefore considered an environmentally sustainable “green” approach for
tackling oil pollution.
Bioremediation strategies may be carried out in situ (decontamination process is
effected at the site of contamination) or ex situ (contaminated material is removed
from the original position to a treatment plant, on site or at another location).
11.7.1 Use of Microbial Consortia
As individual bacterial species or strains often do not have the required genetic/
metabolic diversity to degrade the entire spectrum of components in crude oil, the
general strategy is to use microbial consortia comprising several different species, or
mixed consortia of bacteria and fungi, to achieve complete degradation. It has been
proposed that microbial consortia used in bioremediation efforts should be tailored
to suit the particular condition of the contaminated site as well as the polluting
hydrocarbon classes. Such a strategy may also require the introduction of different
microbial consortia at different stages of the remediation process to ensure complete
removal of hydrocarbon contaminants (Truskewycz et al. 2019).
Knowledge of the microbes’ capacities for biodegradation and the interaction
between the organisms is important for developing optimally functioning bioremediation systems. In microbial communities, individual species may interact with each
other in a synergistic relationship that produces a cocktail of bioactive compounds,
which may include oxidative and hydrolytic enzymes that have been implicated in
processing of various hydrocarbon fractions. Perera et al. (2019) reported a naturally
280
S. Jayasena and M. Perera