Abstract:
An efficient aerobic denitrifying bacteria species was isolated from water in a
Ctenopharyngodon idellus culture pond in Zhongshan City, Guangdong Province in March 2018. The bacteria were identified as
Pseudomonas furukawaii by morphological observation, physiological and biochemical characteristics, and 16S rDNA sequence analysis. This strain was named
Pseudomonas furukawaii ZS1. The denitrification characteristics of the strain and the effects of the carbon source, temperature, pH, C/N ratio and shaking speed on the denitrification ability of strain ZS1 were investigated. The results showed that
P. furukawaii ZS1 was an efficient denitrifier under aerobic conditions. The content of nitrate nitrogen (
\rmNO_\rm3^\rm - -N) decreased from 48.93 mg/L to 1.27 mg/L, the removal efficiency of
\rmNO_\rm3^\rm - -N was 97.40%, and the removal rate was 0.993 mg/L/h; the content of total nitrogen (TN) decreased from 52.04 mg/L to 8.40 mg/L, the removal efficiency was 83.86%, and the removal rate was 0.909 mg/L/h. Single-factor experiments indicated that the optimal conditions for denitrification activity in
P. furukawaii ZS1 were a carbon source of sodium acetate, sodium citrate or glucose; temperatures ranging from 25 to 35℃; a pH of 7.0 to 10.0; a C/N ratio of 15 to 25; and a shaking speed of 100 to 200 r/min. The above results showed that the strain could quickly and effectively remove nitrogen through aerobic denitrification. Therefore, the
P. furukawaii ZS1 strain can be used as a candidate strain for the treatment of pond culture wastewater through biological denitrification.