Screening of aerobic denitrifying bacteria with salt tolerance and characteristics of aerobic denitrification.

In order to screen aerobic denitrifying bacteria with salt tolerance,strain GQ-42 was isolated from activated sludge because of the best denitrifying capability.Based on morphology and physiology of colony as well as 16S rDNA sequence analysis,the strain was characterized as Bacillus cereus.The favorable condition of aerobic denitrification for strain GQ-42 was determined as C/N more than 6,temperature 26~38 ℃,pH 6.0~8.0,dissolved oxygen concentration 5.4~8.5 mg/L and salinity less than 150 g/L.On the condition,all of removal rate of NO3——N were more than 90%,with the best removal rate of NO3——N as 93.77%.