**6.4 Bioremediation**

Due to industrialization, dumping or burying of harmful wastes in the soil or water stream resulted in degradation of surrounding cultivable or arable lands. By tapping these affected soil environments one can discover the microbes degrading the harmful hydrocarbons. As microbes are directly involved in carbon cycles, they may play a role in breaking down the carbon present in the harmful hydrocarbons. Using a function-driven metagenomic approach, new metabolic pathways involved in the biodegradation of aromatic compounds can be discovered. Many rhizospheric microbes produce biosurfactant; these biomolecules play vital role in motility, signaling, and biofilm formation, indicating that biosurfactant governs plant–microbe interaction. In agriculture, biosurfactants can be used for plant pathogen elimination and for increasing the bioavailability of nutrient for beneficial plant associated microbes. Biosurfactants can widely be applied for improving the agricultural soil quality by soil remediation. These biomolecules can replace the harsh surfactant presently being used in million dollar pesticide industries [88]. Studies related to adaptation of microbes in toxic environments may give rise to trace new metagenomic communities useful for efficient bioremediation.
