Isolation and Characteristics of Heterotrophic Nitrification-Aerobic Denitrification Bacterium, <i>Bacillus cereus</i> X7 at High Salinity

Biological nitrogen removal has been focused on in wastewater treatment field recently. A strain X7 was isolated from the sediment of pickle foodstuff wastewater. Based on its 16S rDNA sequence analysis, X7 was identified as Bacillus cereus . At NaCl concentration of 20 g/L, NH 4 + -N removal rate achieved 99.18%, when NO 2 - -N and NO 3 - -N removal rates were 77.24% and 68.6%, respectively. When NaCl concentration ranged from 0 to 40 g/L, the removal rate of NH 4 + -N was more than 97.59%. Therefore, due to the high nitrogen removal rate and excellent salt tolerance, Bacillus cereus X7 had a broad application prospect in the biodenitrification of brine wastewater.