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Soil Microorganisms and Nematodes for Bioremediation and Amelioration

Quite recently, the use of the extraction from algae in the remediation of

wastewater has recently gained interest from the scientific community

which is reported to have great potential as it fixes carbon dioxide (CO2).

Moreover, the algae biomass also contributed to the feedstock for biofuel

production (Huang et al., 2010). Moreover, the recent study by Yamamoto

et al. (2008) suggested that the microalgae were used first time for the reme­

diation of organically enriched sediments. Algae is also useful for the wider

range of organic pollutants which includes PAHs, petroleum hydrocarbons,

polychlorinated biphenyls (PCBs), explosives like trinitrotoluene (TNT) and

pesticides. In addition to it, algae are also used for the biomonitoring and

restoration of the aquatic system and lead to having favor in the phytoex­

traction and biodegradation of many organic pollutants available in the soil.

Moreover, complex formation Ion exchange, and electrostatic interaction aid

in the biosorption of heavy metal ions by algae (Zeraatkar et al., 2016).

1.4.2 GENERAL MECHANISMS FOR MICROBIAL BIOREMEDIATION

In the presence of xenobiotic substances, which have the potential to damage

environmental health and functioning, microorganisms use a variety of

ways to interact and survive. As far as the degradation of organic pollut­

ants are concerned, these rather act as carbon source for microbes which

are consumed either in the presence or absence of oxygen producing less or

non-toxic substrate products. Quite naturally, rapid, and complete degrada­

tion of pollutants is brought under aerobic condition. The key reaction of

aerobic biodegradation is oxidation, which is catalyzed by oxygenase and

peroxidases. Various groups of organisms, such as denitrifiers, methanogens,

and sulfidogens, are actively involved in the bioremediation process under

anaerobic bacteria circumstances.

By combining fermenters and acetogens, as well as methanogens and

sulfate reducers, carbon molecules are decomposed step by step, creating

methane, CO2, ammonia, and hydrogen sulfide. In most cases, anaerobic

degradation mechanisms have been deemed inferior to aerobic degradation.

Anaerobic procedures, on the other hand, have proven to be efficient and

significantly less expensive than aerobic treatment when substantial loads of

easily degraded organic components are present. Microbes with a variety of

methods, including metal-organic complexation, metal-ligand degradation,

oxidation, methylation, enzymatically, metal efflux pumps, intracellular, and

extracellular metal sequestration, and metal exclusion, reclaim heavy metals