Isolation and characterization of an efficient phenanthrene-degrading bacterial strain

摘要

The degradation dynamics of phenanthrene in soil was studied by the incubation method. The half-life of phenanthrene in the non-sterilized contaminated soil was 5.1 d, much shorter than the same in the sterilized soil (21.4 d), due to the major contribution of microbial degradation to the observed removal. The most effective and dominant strain of phenanthrene degradation was isolated and identified by 16S rDNA as Alcaligenes sp.; its growth and degradative capability were highest at 25 °C and pH of 7.0. Among the 9 metal ions tested, Hg2+ produced the largest inhibitory effect.Inoculation of the dominant strain to soil enhanced phenanthrene degradation, and faster degradation rates were observed with larger doses of the strain inoculated.