Isolation of denitrifying bacteria in sea sediment and simulated experiment of removing nitrate-N from seawater

The objective of this research was to isolate denitrifying bacteria from sea sediment and simulate the removal efficiency of nitrate-N by denitrifying bacteria from seawater. The result showed that the isolated denitrifying bacteria could effectively remove nitrate-N from seawater. About 90% of nitrate-N was removed by denitrifying bacteria from seawater within a week in the simulated experiment I (the initial concentration of nitrate-N was 100 mg/L). The removal efficiency of nitrate-N reached about 70% within one day in the simulated experiment II (initial concentration of nitrate-N was 1 mg/L). The final removal efficiency was about 98% and 85% in the simulated experiments I and II, respectively. It was found that there was positive correlation between the concentration of nitrate-N and the number of denitrifying bacteria in seawater. Lots of denitrifying bacteria would disappear and the seawater would become transparent once the process of bioremediation was completed.