降解亚硝酸盐菌株的分离与脱氮能力研究

Isolation and Nitrogen Removal Ability of Nitrite-degrading Bacteria

文章从鳗鲡肠道中筛选出一株具备高效降解亚硝酸盐与硝酸盐和安全的优良芽孢杆菌B1,经过16S rRNA序列分析与生理生化检测,鉴定为地衣芽孢杆菌(Baclicus lincheniformis)。该菌株在葡萄糖10 g/L、28℃好氧条件下培养24 h,亚硝酸盐由85.61 mg/L降低至0.47 mg/L,降解率99.45%;硝酸盐由96.12 mg/L降低至1.04 mg/L,降解率98.92%;氨氮由52.74 mg/L降至18.71 mg/L,降解率64.52%。在模拟处理养殖水体,接种终浓度为106CFU/mL菌株B1后,3 d亚硝酸盐浓度由5.15 mg/L降低至0.41 mg/L,降解率达92.04%,5 d降低至0.09 mg/L,达到养殖水体标准;鳗鲡在含菌株B1终浓度为108CFU/mL水体中,15 d无明显病理变化。试验结果说明:鳗鲡肠道原籍菌株B1具有高效的硝化与好氧反硝化能力,对水产养殖动物安全、无副作用。研究结果表明,菌株B1有助于水产养殖水体的生物脱氮或含高浓度氮的废水处理,具有良好的微生态开发应用前景。

The Bacillus B1 isolated from the intestine of eel, which was highly effective in degrading nitrite and nitrate, was identified as Baclicus lincheniformis by 16 S rRNA sequence analysis and physiological and biochemical tests. When the strain B1 was cultured for 24 hours under the aerobic condition of glucose 10 g/L at 28 ℃, and the nitrite decreased from 85.61 mg/L to 0.47 mg/L, with a degradation rate of 99.45%, nitrate was reduced from 96.12 mg/L to 1.04 mg/L, with a degradation rate of 98.92%, the ammonia nitrogen decreased from 52.74 mg/L to 18.71 mg/L, with a degradation rate of 64.52%. For simulating the treatment of aquaculture water, the strain B1 was inoculated with the final concentration of 106 CFU/mL,the nitrite decreased from 5.15 mg/L to 0.41 mg/L, with a degradation rate of 92.04% after 3 days, and degraded to 0.09 mg/L, conforming to the standard of aquaculture water in 5 days. In addition, there was no obvious pathological change in eel, which was cultured in the water containing 10^(8) CFU/mL strain B1 for 15 days. The results showed that the strain B1, which originated from the gut of eel, has a high capacity for nitrification and aerobic denitrification, and has no side effects on aquaculture animals. The research shows that strain B1 is helpful to the biological denitrification of aquaculture water or the treatment of wastewater with high concentration of nitrogen, and has a good prospect of microecological development and application.