Abstract：Dibutyl phthalate(DBP) is an important plasticizer,and widely used as additives in the manufacturing of plastic, rubber and paint. But DBP is not connected with polymeric matrix by covalent bonds. Thus, DBP is very easy to diffuse into environment and pollutes environment. In order to isolate an DBP-degrading bacterium, strain S-3 was isolated from garbage-contaminated soil using selective culture medium with DBP as the sole carbon source. The strain was identified based on its morphological, physiological and biochemical tests, with reference to 16S rRNA gene sequence analysis (GenBank accession no. KF377815). Strain S-3 was finally identified as Paenibacillus sp.. With HPLC and HPLC-MS method, degrading characteristics of strain S-3 was studied under laboratory conditions and the degrading pathway of DBP was researched preliminarily. The results showed that strain S-3 could degrade more than 82.7% of 100 mg/L DBP within 5 d. The best temperature and pH for the DBP degradation by strain S-3 was 30 ℃ and 7.0, respectively.Bsed on the identified products, the degrading pathway of DBP was speculated. The product was identified as o-phthalic acid. Our research provide theoretical basis to bioremediation technology of DBP pollution.
