Removal of acenaphthene from wastewater by Pseudomonas sp. in anaerobic conditions: the effects of extra and intracellular substances.

ABSTRACT

Sorption and degradation are considered two primary modes of pollutant removal by microorganisms, and extracellular polymeric substances (EPS) have been shown to play an important role in these biological processes. However, their role in removing refractory organic pollutants the effects of intracellular substances in microorganisms remain unclear. In this study, we investigated both the removal mechanism and intracellular substances involved in removing the pollutant acenaphthene (ACE) from Pseudomonas sp. bacteria in anaerobic conditions. The results indicated that the ACE was mainly adsorbed rather than degraded by bacteria. Moreover, ACE had little impact on EPS secretion at concentrations ranging 0-3 mg/L. Cell walls and membranes accounted for more than 70% of ACE adsorption, whereas intra-cellular substances accounted for about 10-25% and the effect of other components on ACE adsorption was not obvious. A possible mechanism of ACE removal by bacteria is proposed.