Degradation of environmental endocrine disruptor di-2-ethylhexyl phthalate by a newly discovered bacterium, Microbacterium sp. strain CQ0110Y

In this study di-2-ethylhexyl phthalate (DEHP)-degradation strain CQ0110Y was isolated from activated sludge. According to the biophysical/biochemical characteristics and analysis of 16S rDNA, the strain was identified as Microbacterium sp. The results of this study showed the optimal pH value and optimal temperature which influenced the degradation rate in wastewater: pH 6.5-7.5, 25-35 degrees C. Kinetics of degradation reaction had been performed at different initial concentrations and different time. Analyzed with SPSS10.0 software, the DEHP degradation can be described as the same exponential model when the initial DEHP concentration was lower than 1,350 mg/l. The kinetics equation was ln C = -0.4087t + A, with the degradation half life of DEHP in wastewater (1.59 days). To the best of our knowledge, this is the first reported case of DEHP degradation by Microbacterium sp. strain.