Biodegradability of chlorinated anilines in waters.
OBJECTIVE
To identify the bacteria tolerating chlorinated anilines and to study the biodegradability of o-chloroaniline and its coexistent compounds.


METHODS
Microbial community of complex bacteria was identified by plate culture observation techniques and Gram stain method. Bacterial growth inhibition test was used to determine t he tolerance of complex bacteria to toxicant. Biodegradability of chlorinated anilines was determined using domesticated complex bacteria as an inoculum by shaking-flask test.


RESULTS
The complex bacteria were identified, consisting of Xanthomonas, Bacillus alcaligenes, Acinetobacter Pseudomonas, and Actinomycetaceae nocardia. The obtained complex bacteria were more tolerant to o-chloroaniline than mixture bacteria in natural river waters. The effects of exposure concentration and inoculum size on the biodegradability of o-chloroaniline were analyzed, and the biodegradation characteristics of single o-chloroaniline and 2, 4-dichloroaniline were compared with the coexistent compounds.


CONCLUSIONS
The biodegradation rates can be improved by decreasing concentration of compounds and increasing inoculum size of complex bacteria. When o-chloroaniline coexists with aniline, the latter is biodegraded prior to the former, and as a consequence the metabolic efficiency of o-chloroaniline is improved with the increase of aniline concentration. Meanwhile, when o-chloroaniline coexists with 2,4-dichloroaniline, the metabolic efficiency of 2,4-dichloroaniline is markedly improved.
Wang
Chao
C
Key Laboratory for Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education College of Environmental Science and Engineering, Hohai University, Nanjing 210098, Jiangsu, China.
Lu
Guang-Hua
GH
Zhou
Yan-Jie
YJ
D000814:Aniline Compounds / Q000378:metabolism* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D001673:Biodegradation, Environmental; D045483:Rivers / Q000737:chemistry / Q000382:microbiology; D014874:Water Pollutants, Chemical / Q000378:metabolism* / Q000494:pharmacology; D018508:Water Purification
D000814:Aniline Compounds; D014874:Water Pollutants, Chemical; C054619:2,4-dichloroaniline; C025257:2-chloroaniline