Studies on the Culture and Applicayion of a Nitrite-oxidizing Bacterium with High Nitrification Activity / 微生物学通报

ABSTRACT

As to a nitrite-oxidizing bacterium screened in our laborator y, the effect of pH, nitrogen sources, carbon sources and sodium chloride on its g rowth was studied in order to obtain high cell density. It showed that the cult ure conditions of nitrite- oxidizing bacterium were 4500mg/L sodium nitrite, 1 .5g/L sodium carbonate, 0~0.5% sodium chloride and 0~0.1% glucose at 28℃~30 ℃, 110 r/min and pH 8.0~8.5. After cultivation for 9 days, the bacteria conc entration reached 4.6?109 MPN/mL and all NO-_2-N in the medium w as converted to NO-_3-N. But the transformation of nitrogen sources was inhibited while the sodium chloride concentration exceeded 0.5% or glucose con centration exceeded 0.1%. According to the test of NO-_2-N conversion with nitrite-oxidizing bacteria in a freshwater aquaculture pond, NO-_2 -N began to decrease on the third day of the moculation of this bacterium and t he concentration dropped from 1.47mol/L to 0.49mol/L after 18 days at 25℃ and pH 8.6.