Untreated Waste Water

Untreated waste water accommodates a large number of organic and inorganic constituents, noxious micro organisms, and toxic metal components in addition to nutrients. Hence, it is necessary to treat the waste water at the source level, before releasing in to the environment in order to reduce the detrimental effects caused by them. Precisely, protection of environment to sustain public health, aquatic life and other socio-economic concerns are the ultimate goals of waste water management (Tchobanoglous and Burton 1991). Major organic chemical parameters of waste water are, total organic carbon (TOC), biochemical oxygen demand (BOD), chemical oxygen demand (COD) and total oxygen demand (TOD). Acidity and alkalinity, pH, salinity, hardness,

Succinctly, bioaugmentation is the introduction of innate or allochthonous strains or genetically engineered microbes to the contaminated sites in order to hasten up the degradation of hazardous material into innocuous form. Genetically engineered microorganisms have shown enhanced degradative potential towards bioaugmentation of soil polluted with aromatic hydrocarbons. Most of the research work has been established with gram negative bacteria belong to genus Flavobacterium, Achromobacter, Sphingobium, Alcaligens and Pseudomonas. In addition, fungi also have been proved as potential agents for bioaugmentation includes, Absidia, Penicillium, Mucor, Achremonium, Aspergillus and Verticillium. There is no any particular group or solitary microorganism that can be universally applied for augmentation (Mrozik

In bioleaching generally, the solid metals are transformed into their soluble forms by microorganisms. For example, Copper metal is extracted in to the aqueous phase as copper sulfate by the oxidation of copper sulfide ore and the waste residue is discarded through solid wastes (Mishra 2005). Bioleaching is an economically feasible and environmentally friendly remediation technique. Most of the heavy metal retrieving microorganisms are acidophiles, which can able to withstand acidic pH range 2.0-4.0. The inorganic and organic substances secreted by these microbes can dissolve the metals into aqueous media. Commonly used acidophilic bacteria for bioleaching application includes, Acidithiobacillus ferrooxidans, Leptospirillum ferrooxidans, Acidithiobacillus thiooxidans and Sulfolobus sp. Also, fungal species such as Aspergillus niger and Penicillium sp. have been proven for their potentiality towards bioleaching (Mishra