Degradation of dimethyl terephthalate by Pasteurella multocida Sa and Sphingomonas paucimobilis Sy isolated from mangrove sediment

Biodegradation of dimethyl terephthalate (DMT) by individual species of bacteria isolated from mangrove sediment was conducted in batch experiments. Four morphologically distinct microorganisms, two of which showed ability to degrade DMT completely, were obtained and identified. Pasteurella multocida Sa displayed the greatest ability in degrading 98 mg DMTl-1 within 60 h. At this initial concentration the rate of DMT degradation by P. multocida Sa was apparently higher than that by Sphingomonas paucimobilis Sy. Based on the data obtained from HPLC/MS/MS analysis degradation of DMT by these bacteria was observed to proceed with formation of monomethyl terephtlate and terephthalate acid (TA) sequentially. However, addition of TA to the culture medium containing DMT as a co-substrate was found to delay aerobic degradation of DMT by P. multocida Sa. From these results, it is evident that environmental bacteria are capable of metabolizing DMT as sole carbon and energy source and may be used in aerobic treatment of wastewater containing DMT.