Biodegradation of phenol and m-cresol by mutated Candida tropicalis.
The phenol and m-cresol biodegradations were studied using the mutant strain CTM 2 obtained by the He-Ne laser irradiation on wild-type Candida tropicalis. The results showed that C. tropicalis exhibited the increased capacity of phenolic compounds degradation after laser irradiation. It could degrade 2600 mg/L phenol and 300 mg/L m-cresol by 5% inoculum concentration, respectively. In the dual-substrate biodegradation system, 0-500 mg/L phenol could accelerate m-cresol biodegradation, and 300 mg/L m-cresol could be completely utilized within 46 hr at the presence of 350 mg/L phenol. Besides, the maximum biodegradation of m-cresol could reach 350 mg/L with 80 mg/L phenol within 61 hr. Obviously, phenol, as a growth substrate, could promote CTM 2 to degrade m-cresol, and was always preferentially utilized as carbon source. Comparatively, low-concentration m-cresol could result in a great inhibition on phenol degradation. In addition, the kinetic behaviors of cell growth and substrate biodegradation were described by kinetic model proposed in our laboratory.
Jiang
Yan
Y
State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China. yjiang@hit.edu.cn
Cai
Xun
X
Wu
Di
D
Ren
Nanqi
N
D001673:Biodegradation, Environmental; D041022:Candida tropicalis / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D003408:Cresols / Q000378:metabolism*; D019800:Phenol / Q000378:metabolism*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000378:metabolism*
D003408:Cresols; D014874:Water Pollutants, Chemical; C032538:4-cresol; D019800:Phenol