Integrative approaches for assessing the ecological sustainability ofin situbioremediation

Abstract

Application of microbial metabolic potential (bioremediation) is accepted as an environmentally benign and economical measure for decontamination of polluted environments. Bioremediation methods are generally categorized into ex situ and in situ bioremediation. Although in situ bioremediation methods have been in use for two to three decades, they have not yet yielded the expected results. Their limited success has been attributed to reduced ecological sustainability under environmental conditions. An important determinant of sustainability of in situ bioremediation is pollutant bioavailability. Microbial chemotaxis is postulated to improve pollutant bioavailability significantly; consequently, application of chemotactic microorganisms can considerably enhance the performance of in situ degradation. The environmental fate of degradative microorganisms and the ecological consequence of intervention constitute other important descriptors for the efficiency and sustainability of bioremediation processes. Integrative use of culture-dependent, culture-independent methods (e.g. amplified rDNA restriction analysis, terminal restriction fragment length polymorphism, denaturing/thermal gradient gel electrophoresis, phospholipid fatty acid, etc.), computational and statistical analyses has enabled successful monitoring of the above aspects. The present review provides a detailed insight into some of the key factors that affect the efficiency of in situ bioremediation along with a comprehensive account of the integrative approaches used for assessing the ecological sustainability of processes. The review also discusses the possibility of developing suicidal genetically engineered microorganisms for optimized and controlled in situ bioremediation.

Metabolism Dependent Chemotaxis of Pseudomonas aeruginosa N1 Towards Anionic Detergent Sodium Dodecyl Sulfate

“…Results observed are in accordance with previous reports, which indicate that biodegradable xenobiotic compounds also act as chemoattractants [2,[5][6][7]. Many aromatic acids have been reported to be attractants for Pseudomonas putida PRS2000 [8]. Chemotaxis of Burkholderia sp.…”

“…It has been reported that members of the genus Pseudomonas are known to degrade and metabolize a wide variety of xenobiotic compounds and also that they show chemotactic response towards many of these compounds. These include naphthalene [2], chlorinated benzoates and 4-hydroxybenzoate [3,4], methyl parathion and p-nitrophenol [5], benzene, toluene, and trichloroethylene [6], nitro-benzoates and amino-benzoates [7], and aromatic acids [8]. It is believed that chemotaxis plays an important role in metabolism of xenobiotic compounds as it increases the availability of the chemical to the microbe and plays a positive role in metabolism of xenobiotic compounds [9].…”

Microbial degradation of pesticide: A review

“…The Pseudomonas sp. 1G is reported for biotransformation of imidacloprid (Pandey et al, 2009), Leifsonia sp. (Anhalt et al, 2008).…”

Pesticide-Derived Aromatic Amines and Their Biotransformation

“…Finally, soils treated by bioremediation may be re-used, at least for industrial crops, if acceptable target pollutant levels are reached (Mougin et al, 2009). However, current strategies generally categorized into ex situ and in situ bioremediation have not yet yielded the expected efficiency (Pandey et al, 2009). Fundamental research is needed to reduce cost and to increase performance of bioremediation techniques.…”