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Biology and Biotechnology of Environmental Stress Tolerance in Plants, Volume 3

polyaromatic compounds. The mechanism behind the detoxification is that

many bacteria use the pollutant as the sole source of carbon and energy.

Bacteria such as Mycobacterium, Escherichia, and Bacillus are commonly

used for the bioremediation of heavy metals and PAHs. The mechanism of

use of PAHs as the source of carbon as they break down the substances

like anthracene, pyrene, naphthalene, phenanthrene, and benzopyrene in the

presence of heavy metals such as Cd, Cu, Cr, and Pb that are reported to

have occurred with PAHs. The enzyme used by the microbes for aerobic

degradation is methane monooxygenase which acts against a wider range

of compounds that includes chlorinated aliphatic trichloroethylene and

1,2-dichloroethane.

1.4.1.1.2 Anaerobic Bacteria

There use isn’t as prevalent as aerobic bacteria. These are primarily used

for the bioremediation of the polychlorinated biphenyls (PCBs) which are

present in the river sediments, dechlorination of the solvent trichloroethylene

(TCE) and chloroform.

1.4.1.2 FUNGI

The group of fungus was reported to be used as the bioagent for bioreme­

diation of soil. The fungi such as the white-rot fungus Phanaerochaete

chrysosporium was reported to have the ability to degrade the extremely

diverse range of pollutants and heavy metals. The growth of the fungus was

accelerated by the addition of straw, sawdust, and corn cobs where it acts as

the substrate. Moreover, the heavy metal pollutant might also be remediated

by the fungal communities such as Pleurotus, Acremonium, and Fusarium.

However, the microbial consortia were reported to be associated with the

effective strategies for remediation of heavy metals and PAHs. There are

some well-established techniques where the process of immobilization

(Huang et al., 2016) and compost (Poulsen & Bester, 2010) can protect the

microbes from heavy metals and PAHs, thereby enhancing the activity of

microorganisms.

1.4.1.3 ALGAE

Several species of algae have shown the ability to biosorb organic and inor­

ganic pollutants, specifically heavy metals and even radioactive substances.