RESUMO
A bacterial strain which could grow well on the substrate of PAEs as the sole source of carbon and energy was isolated from contaminated sludge in the river of WeiFang in ShangDong province and it was designated as JDC-3. Based on the morphology,biophysical and biochemical properties as well as molecular characteristics,this isolate was preliminarily identified as Delftia sp.. A fragment of phthalate dioxygenase gene was successfully amplified from the genus of Delftia for the first time using a set of degenerate primers. Meanwhile,the degradation capability of JDC-3 was determined by HPLC using DMP as test substrate. The results showed that the optimal pH and temperature were at 7.0～8.0 and 30?C～35?C respectively. The degradation kinetics of JDC-3 was studied in different initial DMP concentration under optimal conditions. The results indicated that the degradation dynamic equation was ln C =-0.06837 t + A when DMP concentration was lower than 300 mg/L,with half life of 12.48 h. The degradation rate decreased and half life of JDC-3 prolonged as the initial concentration kept on increasing.