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Soil Microorganisms and Nematodes for Bioremediation and Amelioration

1.3.2.6 BIOFILMS

It consists of an organized population of bacterial, algal, or other cell types

contained in a polymer matrix that is self-produced. Waste can accumulate

within biofilm to toxic levels. Used for treatment of recalcitrant compounds.

1.3.2.7 BIOLEACHING

Involves extraction of desired metal from low-grade ores with the help

of microorganisms. Microorganisms produce acids from reduced sulfur

compounds, and the acids solubilize the desired metals.

1.4 MICROBIAL BIOREMEDIATION: A GREEN TECHNOLOGY FOR

ENVIRONMENTAL REMEDIATION

The industrial revolution in recent decades enabled humans to explore and

exploit natural resources which leads to the deterioration of the environment

and human health. For dealing with environmental pollution, bioremediation

is the most novel and ideal solution for pollution abatement. This approach

uses biological systems for the treatment of contaminants.

1.4.1 MICROORGANISMS INVOLVED IN BIOREMEDIATION

1.4.1.1 BACTERIA

Bacteria are the most important microbes in the clean-up of contaminated

soil and water because they break up dead material into inorganic nutrients

very quickly. Different pesticides including chlorinated pesticides can easily

be digested by bacteria. Bacteria can act on both aerobic and anaerobic

functions by using the enzymatic pathway and catabolic reaction of micro­

organisms to break down soil contaminants or convert them into nontoxic

substances.

1.4.1.1.1 Aerobic Bacteria

The variety of anaerobic bacteria is recognized for the ability to degrade

which includes Pseudomonas, Alcaligenes, Sphingomonas, Rhodococcus,

and Mycobacterium. The aforementioned bacteria were reported to degrade

and decay the pesticide and hydrocarbon which are generally alkanes and