Screening,identification and degrading characteristics of a high phenol-degrading bacterial strain

In order to screen high phenol-degrading bacterial strains,bacteria in the sludge of a coking plant was acclimated successively by the inorganic salt medium containing phenol as a sole carbon source.Phenol-degrading bacterial strain was identified preliminarily by its morphological,physiological and biochemical characteristics,and 16S rDNA sequences.The phenol degradation ability under different temperature,pH,inoculation amount,and optimal condition was determined by 4-AAP spectrophotometric method.The results showed that the strain JDM-2-1 could tolerate phenol of 2 200 mg/L,and it was identified as Bacillus sphaericus.The optimal temperature of phenol degradation was 35 ℃,and the optimal pH value was 5.0.The phenol degradation ability of JDM-2-1 was correlated positively to inoculatin amount.Under optimal conditions,it could completely degrade phenol of 800 mg/L in 42 h when inoculation amount was 2%,and it could degrade phenol of 1 600 mg/L partly as well.The results indicated that the JDM-2-1 was a adaptable,high phenol-degrading bacterial strain.