| The biodegradation of phenol,m-cresol and 4-chlorophenol by the pure and mixed culture of Pseudomonas putida and Candida tropicalis was investigated.The results showed that,with the initial concentrations of 100，50 and 60 mg·L-1for phenol,m-cresol and 4-chlorophenol,respectively,and an increase in the absolute value of the kinetic constant k of 19.0%， 2.6% and 46.4% for the degradation of phenol,m-cresol and 4-chlorophenol,respectively,was reached by dual culture compared with pure culture.The activity assays of phenol hydroxylase and catechol 1， 2-dioxygenase demonstrated phenol was degraded via the ortho-cleavage pathway in both of the two species.Further experiments via high performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry techniques (LC-MS) suggested the degradation of three phenolic compounds could be accelerated due to co-metabolism by Pseudomonas putida of cis,cis-muconic acid,and 4-carboxymethylenebut-2-en-4-olide accumulated in phenol and 4-chlorophenol degradation,respectively， 3， 4-dihydroxybenzoic acid， 2-maleylacetate,and 3-oxoadipate in the degradation of m-cresol by Candida tropicalis in dual culture. |
