Abstract
Synthetic organic compounds in polymeric materials can migrate out to the environment and disrupt the endocrine system in organisms, including humans. These compounds can also promote the growth of microorganisms on surfaces of materials. They have been detected in a wide range of environments and their concentration can be as high as 10 g L-1 of phthalic acid and dimethyl phthalate ester (DMPE) in landfill leachate. We initiated an investigation on biodegradability of phthalic acid and DMPE’s. Enrichment cultures of bacteria obtained from activated sludge and mangrove can fully mineralize this group of compounds within a short period of time. However, it was also found that single species of bacteria were not capable of completely degrading DMPE’s and consortia of two or three pure species could mineralize DMPE’s at an initial concentration of 400 m g L-1 within one week. Two selective systems consisting of bacteria isolated from activated sludge and mangrove are discussed here. Degradation intermediates were isolated and identified, and the degradation pathway has been established. It is apparent that environmental hormones DMPE’s could be mineralized by natural microorganisms in proper association.
