The problem of limited bioavailability is considered one of the major bottle necks for further progress in soil bioremediation technology Contaminants are believed to be bioavailable only when they are present in the aqueous solution. However, since many pollutants sorb to soil constituents or are dissolved in separate phase liquids, the bulk amounts appear to be unavailable to microorganisms.
The proposed project endeavours to identify and characterise bacterial strategies of promoting bioavailability of hydrophobic pollutants and to evaluate the applicability of the microorganisms for in-situ biotreatment. The project thus represents a completely new approach towards the improvement of bioremediation technology.
In its experimental approach, the project will concentrate on the biodegradation of a major group of hydrophobic pollutants, Polycyclic Aromatic Hydrocarbons (PAHs). PAH degrading bacteria will be examined, which have been selected not only for their metabolic properties, but also for their ability to degrade PAHs provided in the sorbed or NAPL-dissolved state. Using a multi-disciplinary approach, we will examine if such bacteria enhance hydrophobic substrate transfer (i) by means of the emulsifying properties of their cell surfaces and/or (ii) by adhesion to hydrophobic sorbent materials reducing the distance to the sorbed pollutant. The mass transfer-promoting properties of the bacteria will be examined at the physiological level and genetic level. The importance of bacterial characteristics beyond biochemical capacities, for the degradation of PAHs in soils and the implications for in situ bioremediation, will be evaluated. Such bacterial capabilities may be usable as an innovative biotechnology for maximising the bioavailability of hydrophobic pollutants, through carefully directed stimulation of indigenous bacteria or through inoculation with new strains from this project.
The project partnership includes leading European laboratories experienced in the disciplines of biodegradation, bacterial genetics, bacterial physiology and soil microbial ecology. The level of industrial interest in this proposal is reflected by the involvement of an industrial partner from the bioremediation industry. During the course of the project the industrial partner will act as advisor for the research and development effort, to focus the project towards field relevance and as a liaison with end-users.
Funding SchemeCSC - Cost-sharing contracts
1018 WV Amsterdam