Abstract:For the application of a heterotrophic nitrifying-aerobic denitrifying bacteria strain X3 in mariculture, the effects of several environmental factors, including temperature, salinity, pH, C∶N ratio, and carbon source on the growth and nitrogen removing ability of strain X3 were examined in the laboratory conditions, and its sensitivity to different antibiotics was also explored. The results showed that, the optimal condition for strain X3 to grow and remove nitrogen were 28℃, salinity of 30, pH 8.5, using sodium acetate as the carbon source and at a C∶N ratio of 10∶1. This strain grew well and kept over 80% nitrogen removal rate at 25~37℃, 20~80 salinity, pH 7.5~9.5 with a C∶N ratio range of 5∶1~15∶1 and sodium acetate or glucose as the carbon source. Especially, this strain was able to grow in the medium with salinity of 150. The result of sensitivity to antibiotics indicated that strain X3 was only sensitive to norfloxacin, ofloxacin and polymyxa amphotericin B, while resistant to the other 27 antibiotics. Therefore, it can be concluded that strain X3 has excellent adaptability to the environment of mariculture and huge application potential in mariculture water purification.
