Biodegradation of complex bacteria on phenolic derivatives in river water.
OBJECTIVE
To isolate, incubate, and identify 4-chlorophenol-degrading complex bacteria, determine the tolerance of these bacteria to phenolic derivatives and study their synergetic metabolism as well as the aboriginal micrpbes and co-metabolic degradation of mixed chlorophenols in river water.


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 the tolerance of complex bacteria to toxicants. Biodegradability of phenolic derivatives was determined by adding 4-chlorophenol-degrading bacteria in river water.


RESULTS
The complex bacteria were identified as Mycopiana, Alcaligenes, Pseudomonas, and Flavobacterium. The domesticated complex bacteria were more tolerant to phenolic derivatives than the aboriginal bacteria from Qinhuai River. The biodegradability of chlorophenols, dihydroxybenzenes and nitrophenols under various aquatic conditions was determined and compared. The complex bacteria exhibited a higher metabolic efficiency on chemicals than the aboriginal microbes, and the final removal rate of phenolic derivatives was increased at least by 55% when the complex bacteria were added into river water. The metabolic relationship between dominant mixed bacteria and river bacteria was studied.


CONCLUSIONS
The complex bacteria domesticated by 4-chlorophenol can grow and be metabolized to take other chlorophenols, dihydroxybenzenes and nitrophenols as the sole carbon and energy source. There is a synergetic metabolism of most compounds between the aboriginal microbes in river water and the domesticated complex bacteria. 4-chlorophenol-degrading bacteria can co-metabolize various chlorophenols in river water.
Lu
Guang-Hua
GH
Key Lab for Hydrology-Water Resources and Hydraulic Engineering, Key Laboratory for Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environmental Science and Engineering, Hohai University, Jiangsu, China.
Wang
Chao
C
Sun
Zhe
Z
D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D010636:Phenols / Q000378:metabolism*; D045483:Rivers / Q000382:microbiology*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism; D018508:Water Purification
D010636:Phenols; D014874:Water Pollutants, Chemical; D014867:Water