Polycyclic aromatic hydrocarbons (PAHs) are a class of organic compounds that have accumulated in the natural environment mainly as a result of anthropogenic activities such as the combustion of fossil fuels. Interest has surrounded the occurrence and distribution of PAHs for many decadesdue to their potentially harmful effects to human health. This concern has promptedresearchers to address ways to detoxify/remove these organic compounds from the natural environment. Bioremediation is one approach that has been used to remediate contaminated land and waters, and promotes the natural attenuation of the contaminants using the in situ microbial community of the site. This review discusses the variety of fungi and bacteria that are capable of these transformations, describes the major aerobic and anaerobic breakdown pathways, and highlights some of the bioremediation technologies that are currently available.  2005 Society of Chemical Industry

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Bioremediation of polycyclic aromatic hydrocarbons: current knowledge and future directions

Bioremediation approaches for organic pollutants: a critical perspective

Polycyclic aromatic hydrocarbons (PAHs) include a group of organic priority pollutants of critical environmental and public health concern due to their toxic, genotoxic, mutagenic and/or carcinogenic properties and their ubiquitous occurrence as well as recalcitrance. The increased awareness of their various adverse effects on ecosystem and human health has led to a dramatic increase in research aimed towards removing PAHs from the environment. PAHs may undergo adsorption, volatilization, photolysis, and chemical oxidation, although transformation by microorganisms is the major neutralization process of PAH-contaminated sites in an ecologically accepted manner. Microbial degradation of PAHs depends on various environmental conditions, such as nutrients, number and kind of the microorganisms, nature as well as chemical property of the PAH being degraded. A wide variety of bacterial, fungal and algal species have the potential to degrade/transform PAHs, among which bacteria and fungi mediated degradation has been studied most extensively. In last few decades microbial community analysis, biochemical pathway for PAHs degradation, gene organization, enzyme system, genetic regulation for PAH degradation have been explored in great detail. Although, xenobiotic-degrading microorganisms have incredible potential to restore contaminated environments inexpensively yet effectively, but new advancements are required to make such microbes effective and more powerful in removing those compounds, which were once thought to be recalcitrant. Recent analytical chemistry and genetic engineering tools might help to improve the efficiency of degradation of PAHs by microorganisms, and minimize uncertainties of successful bioremediation. However, appropriate implementation of the potential of naturally occurring microorganisms for field bioremediation could be considerably enhanced by optimizing certain factors such as bioavailability, adsorption and mass transfer of PAHs. The main purpose of this review is to provide an overview of current knowledge of bacteria, halophilic archaea, fungi and algae mediated degradation/transformation of PAHs. In addition, factors affecting PAHs degradation in the environment, recent advancement in genetic, genomic, proteomic and metabolomic techniques are also highlighted with an aim to facilitate the development of a new insight into the bioremediation of PAH in the environment.

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Current State of Knowledge in Microbial Degradation of Polycyclic Aromatic Hydrocarbons (PAHs): A Review

Bioremediation of soils contaminated with polycyclic aromatic hydrocarbons, petroleum, pesticides, chlorophenols and heavy metals by composting: Applications, microbes and future research needs

http://dzumenvis.nic.in/Microbes%20and%20Metals%20Interaction/pdf/Impact%20of%20composting%20strategies.pdf

Impact of composting strategies on the treatment of soils contaminated with organic pollutants.

Induction of PAH-catabolism in mushroom compost and its use in the biodegradation of soil associated phenanthrene

The degradation of benzene in pasteurized spent mushroom substrate (SMS) was assessed. Following a 3 month enrichment in the presence of a variety of BTEX compounds, the extent of [U-14C]benzene mineralization in the pasteurized SMS increased with increasing incubation temperature (18°C<37°C<50°C). The concentration as well as the chemical composition used to enrich the compost's degradative activity was also shown to be involved in determining the extent of benzene mineralization. SMS induced on a 12.5 mM BTEX mixture mineralized more benzene than composts induced using 500 μM benzene, 500 μM o-xylene, or 2.5 mM BTEX mixture. In the absence of a pre-enrichment period, benzene mineralization was minimal.

Terry R. Fermor

Papers

Impact of composting strategies on the treatment of soils contaminated with organic pollutants.

Induction of PAH-catabolism in mushroom compost and its use in the biodegradation of soil associated phenanthrene

Factors affecting the mineralization of [U-14C]benzene in spent mushroom substrate

Enhanced mineralization of UL-14C-pentachlorophenol by mushroom composts.

Bioremediation: use of composts and composting technologies.