Anaerobic biodegradation of phenol by Candida albicans PDY-07 in the presence of 4-chlorophenol

Biodegradation of phenol and 4-chlorophenol (4-cp) using pure culture of Candida albicans PDY-07 under anaerobic condition was studied. The results showed that the strain could completely degrade up to 1,800 mg/l phenol within 68 h. The capacity of the strain to degrade phenol was higher than that to degrade 4-cp. In the dual-substrate system, 4-cp intensely inhibited phenol biodegradation. Comparatively, low-concentration phenol from 25 to 150 mg/l supplied a carbon and energy source for Candida albicans PDY-07 in the early phase of biodegradation and accelerated the assimilation of 4-cp, which resulted in that 50 mg/l 4-cp was degraded within less time than that without phenol. While the biodegradation of 50 mg/l 4-cp was inhibited in the presence of 200 mg/l phenol. In addition, the intrinsic kinetics of cell growth and substrate degradation were investigated with phenol and 4-cp as single and dual substrates in batch cultures. The results demonstrated that the models adequately described the dynamic behaviors of biodegradation by Candida albicans PDY-07.