Bioremediation for Environmental Management

Environmental Management involves control of emissions and effluents into air, water or soil. Bioremediation makes a better effective approach possible. Microbes bioremediate the environment as they biodegrade the pollutants to obtain energy. Among aromatics, phenols and their derivatives form the principal group of environmental contaminants. Even at low levels they are toxic and they pose a threat to the biosphere because of their recalcitrant nature. We have isolated a microorganism which is capable of degrading phenolic compounds even at high concentrations. The available taxonomic evidences have suggested that the bacterial strain is a novel species within the genus Arthrobacter. The microorganism has the ability to degrade various aromatic pollutants. It has been hypothesized that biodegradation of aromatics in soil can be enhanced by introducing plants which exude phenolic compounds through their roots. There is evidence for root exudates enhancing the expression and activity of specific enzymes that degrade aromatics. Plants release 10-20% of total carbon during photosynthesis through their roots in the soil. Such root exudates are rich in biodegradable organic molecules that stimulate microbial growth. Plants provide nutrients necessary for the microbes to thrive, while microbes provide a healthier soil environment. Aromatic compounds in root exudates such as phenol have been shown to induce dioxygenase enzymes which initiate the biodegradation process. We have made an attempt to show that the enzymes involved in the metabolism of phenolic compounds in the soil bacteria isolated from the contaminated site are induced by the root exudates and the specific activities of the enzymes in the isolate is remarkably high compared to other microorganisms. Hence, bioremediation plays an increasingly important role as a result of new and emerging techniques and processes