好氧反硝化细菌N6-1亚硝酸盐还原活性的研究

Study on the Nitrite-reducing Activity of Aerobic Denitrifying Bacterial Strain N6-1

摘要:

针对本实验室筛选得到的1株好氧反硝化细菌(Aerobic Denitrifying Bacteria)N6-1, 研究了培养条件和培养基组分对菌株亚硝酸盐还原活性的影响。结果表明, 其最适培养条件为30℃、摇床转速120 r/min、初始pH 8.5, 分别以NaNO2和乙酸钠为唯一氮源和碳源时, 最适碳氮比为12; 初始NaNO2浓度为2 g/L时, 培养20 h后NO2--N全部被还原, 平均还原速率可达20.3 mg/L·h; 1.5% NaCl和1%蛋白胨对其亚硝酸盐还原活性没有明显影响; 10 L发酵罐培养24 h后菌体浓度高达1.2×1011 CFU/mL。

Abstract:

The nitrite-reducing activity of aerobic denitrifying bacterial strain N6-1 was studied. It showed that the nitrite-reducing activity reached the highest at 30℃, 120 r/min, pH 8.5 and C/N ratio 12, using CH3COONa and NaNO2 as the sole carbon source and nitrogen source, respectively. When the initial NaNO2 concentration was 2 g/L, NO2--N was reduced completely after 20 hours cultivation with the reducing rate of 20.3 mg/L·h. There would be no effect on its nitrite-reducing activity in the present of 1.5% NaCl or 1% peptone. The cell concentration could reach 1.2×1011 CFU/mL after 24 hours cultivation in 10 L fermentor.