title: Biodegradation of phenol and 4-chlorophenol by the yeast Candida tropicalis.
abstract: Biodegradation of phenol and 4-chlorophenol (4-cp) using a pure culture of Candida tropicalis was studied. The results showed that C. tropicalis could degrade 2,000 mg l(-1) phenol alone and 350 mg l(-1) 4-cp alone within 66 and 55 h, respectively. The capacity of the strain to degrade phenol was obviously higher than that to degrade 4-cp. In the dual-substrate system, 4-cp intensely inhibited phenol biodegradation. Phenol beyond 800 mg l(-1) could not be degraded in the presence of 350 mg l(-1) 4-cp. Comparatively, low-concentration phenol from 100 to 600 mg l(-1) supplied a sole carbon and energy source for C. tropicalis in the initial phase of biodegradation and accelerated the assimilation of 4-cp, which resulted in the fact that 4-cp biodegradation velocity was higher than that without phenol. And the capacity of C. tropicalis to degrade 4-cp was increased up to 420 mg l(-1) with the presence of 100-160 mg l(-1) phenol. In addition, the intrinsic kinetics of cell growth and substrate degradation were investigated with phenol and 4-cp as single and mixed substrates in batch cultures. The results illustrated that the models proposed adequately described the dynamic behaviors of biodegradation by C. tropicalis.
authors.affiliation: Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jiang
authors.forename: Jianping
authors.initials: J
authors.lastname: Wen
authors.forename: Li
authors.initials: L
authors.lastname: Lan
authors.forename: Zongding
authors.initials: Z
authors.lastname: Hu
mesh_terms: D001673:Biodegradation, Environmental; D041022:Candida tropicalis / Q000254:growth & development / Q000378:metabolism*; D002733:Chlorophenols / Q000378:metabolism*; D007700:Kinetics; D013379:Substrate Specificity
chemical_list: D002733:Chlorophenols