3.3.1 Microbial Treatments for Bioremediation
Microorganisms account for half of our planet’s biomass; however, very little (5%)
is known about the microbial diversity in the biosphere (Curtis and Reinhard 1994).
Microbes have a high capability of multiplication that offers a more economical and
eco-friendly strategy for the reduction of environmental pollutants; also, it keeps a
simpler way to biodegrade many xenobiotic compounds. The present microbial
remediation researches focus on degrading persistent organic compounds by isolating and identifying specific microorganism or consortium of microorganism which
can breakdown the substances, such as benzene, phenol, toluene, atrazine, etc. Even
complex
compounds,
such
as
polychlorinated
biphenyl
(PCBs),
dichlorodiphenyltrichloroethane (DDT), and hexachlorocyclohexane (HCH), can
also be degradable by appropriate microbes (Saleh et al. 1980; Yagi and Sudo
1980; Dmochewitz and Ballschmiter 1988; Solis et al. 2012). According to the
literature, the microbial strains used to degrade different chemicals are typically
extracted from environmental samples (wastewaters, sludge, manure, and polluted
soil) and developed with traditional enrichment techniques. Several documentations
have been reported about the microbial sources, including fungi, bacteria, yeasts,
algae, and actinomycetes (Lim et al. 2010).
The effluents from textile industries contain a variety of organic and inorganic
compounds, as it relies on its source for its particular existence and concentrations.
Fatty acids, carbohydrates, and proteins are the common organic matters present in
the textile effluents. Heavy metals, salts, sulfides, sulfates, and nitrates are also
observed extensively as inorganic pollutants. Although microorganisms may express
enzymes that are capable of degrading the most recalcitrant pollutants, still issues do
remain. The application of enzyme technology is well-known not only in textile
production industry, as a way of destiny, but also in bioremediation processes.
Therefore, enzymology can be considered as a key stone for environmental biotechnology, in specific, biological remediation, be it aerobic or anaerobic. For bioremediation, the most studied enzymes are lignin peroxidase (EC 1.11.1.14), manganese
peroxidase (EC 1.11.1.13), and laccases (EC 1.10.3.2). Among these, laccases
possess tremendous potential for bioremediation, because of their remarkable hydrolyzing ability to allow a wider spectrum of applications (Ellis et al. 2012).
Enzymes are versatile biocatalysts, with an increasing number of applications in
biotechnology. Fascinatingly, its properties allow them to attract and get advantage
for conventional treatments against pollutants. The key challenges of the bioengineering strategy include the development of protocol for the production of precious
enzymes, using recombinant DNA techniques and deployment of such techniques,
in order for a desired lacquer to be manufactured under large-scale yield and robust
industrial applications. This strategy can be a valuable scope to push the enzyme
ideally suited for industrial applications (Rodriguez-Couto 2013).
The efficacy of dyes decolorization is stated to have enzymes from both anaerobic
and aerobic systems, typically from white-rot fungus, Phanerochaete
chrysosporium. The laccases and manganese/lignin peroxidases that are capable of
206
K. Rajan et al.
Microorganisms account for half of our planet’s biomass; however, very little (5%)
is known about the microbial diversity in the biosphere (Curtis and Reinhard 1994).
Microbes have a high capability of multiplication that offers a more economical and
eco-friendly strategy for the reduction of environmental pollutants; also, it keeps a
simpler way to biodegrade many xenobiotic compounds. The present microbial
remediation researches focus on degrading persistent organic compounds by isolating and identifying specific microorganism or consortium of microorganism which
can breakdown the substances, such as benzene, phenol, toluene, atrazine, etc. Even
complex
compounds,
such
as
polychlorinated
biphenyl
(PCBs),
dichlorodiphenyltrichloroethane (DDT), and hexachlorocyclohexane (HCH), can
also be degradable by appropriate microbes (Saleh et al. 1980; Yagi and Sudo
1980; Dmochewitz and Ballschmiter 1988; Solis et al. 2012). According to the
literature, the microbial strains used to degrade different chemicals are typically
extracted from environmental samples (wastewaters, sludge, manure, and polluted
soil) and developed with traditional enrichment techniques. Several documentations
have been reported about the microbial sources, including fungi, bacteria, yeasts,
algae, and actinomycetes (Lim et al. 2010).
The effluents from textile industries contain a variety of organic and inorganic
compounds, as it relies on its source for its particular existence and concentrations.
Fatty acids, carbohydrates, and proteins are the common organic matters present in
the textile effluents. Heavy metals, salts, sulfides, sulfates, and nitrates are also
observed extensively as inorganic pollutants. Although microorganisms may express
enzymes that are capable of degrading the most recalcitrant pollutants, still issues do
remain. The application of enzyme technology is well-known not only in textile
production industry, as a way of destiny, but also in bioremediation processes.
Therefore, enzymology can be considered as a key stone for environmental biotechnology, in specific, biological remediation, be it aerobic or anaerobic. For bioremediation, the most studied enzymes are lignin peroxidase (EC 1.11.1.14), manganese
peroxidase (EC 1.11.1.13), and laccases (EC 1.10.3.2). Among these, laccases
possess tremendous potential for bioremediation, because of their remarkable hydrolyzing ability to allow a wider spectrum of applications (Ellis et al. 2012).
Enzymes are versatile biocatalysts, with an increasing number of applications in
biotechnology. Fascinatingly, its properties allow them to attract and get advantage
for conventional treatments against pollutants. The key challenges of the bioengineering strategy include the development of protocol for the production of precious
enzymes, using recombinant DNA techniques and deployment of such techniques,
in order for a desired lacquer to be manufactured under large-scale yield and robust
industrial applications. This strategy can be a valuable scope to push the enzyme
ideally suited for industrial applications (Rodriguez-Couto 2013).
The efficacy of dyes decolorization is stated to have enzymes from both anaerobic
and aerobic systems, typically from white-rot fungus, Phanerochaete
chrysosporium. The laccases and manganese/lignin peroxidases that are capable of
206
K. Rajan et al.