一株嗜热嗜盐亚硝化单胞菌的氨氧化活性

The Ammonia Oxidation Activity of a Thermophilic and Halophilic Nitrosomonas

作者从皮革废水中分离得到一种亚硝化单胞菌富集物,研究了其对高温高盐的适应性。测定了17~47℃和0.2%~6.2%盐度条件下的亚硝氮积累量,以及温度与盐度的交互作用对耗氧量的影响,并比较了该富集培养物与不耐盐不耐热的Nitrosomonas eutropha CZ-4在39℃的高盐皮革污水中的氨氧化效果。结果表明,本富集培养物种只有一种AOB,其16S rRNA基因序列与Nitrosomonas halophila的相似度为97.40%,故命名为N.halophila LFY-1。LFY-1最适于亚硝氮积累的温度和盐度分别为40.5℃和1.2%,亚硝氮积累的半数抑制温度和半数抑制盐度分别为45.9℃和3.3%;LFY-1最适于耗氧的温度和盐度分别为39℃和2.2%,耗氧的半数抑制温度和盐度分别高于45℃和4.2%,但高温高盐对耗氧量无交互作用;LFY-1在高温高盐皮革污水中的亚硝氮积累速率可以达到0.84 mg/(L·h),平均代时为15.5 h,均显著优于CZ-4。上述结果说明本富集培养物具有嗜热嗜盐且耐热耐盐的特性,具有在高温/高盐污水中的应用优势。

An Nitrosomonas enrichment was isolated from a leather wastewater,and its adaptability to high-temperature and high-salinity was studied.The accumulation of nitrite at 17~47℃and 0.2%~6.2%salinity were measured,and the cross-interaction of high-temperature and high-salinity on the oxygen consumption were also determined.Moreover,the ammonia-oxidation ability in a high-temperature and high-salinity leather wastewater were compared between the AOB enrichment and a Nitrosomonas eutropha CZ-4,which was a purified strain without the ability to tolerant high-temperature and high-salinity.The result indicated that there was only one AOB in this enriched culture,and its 16S rRNA gene sequence was similar to Nitrosomonas halophila with identity of 97.40%,so it was named as N.halophila LFY-1.For the nitrite accumulation of LFY-1,the optimum temperature and salinity were 40.5℃and 1.2%,respectively,and the half-inhibition temperature and half-inhibition salinity were 45.9℃and 3.3%,respectively.For the oxygen consumption,the optimum temperature and salinity were 39℃and 2.2%,respectively,and the half-inhibition temperature and salinity were higher than 45℃and 4.2%,respectively.However,the cross-interaction of high-temperature and high-salinity on the oxygen consumption was not detected.In the high-temperature and high-salinity leather wastewater,the nitrite accumulation rate of LFY-1 reached 0.84 mg/(L·h)and the average generation time was 15.5 h,which are all significantly better than CZ-4.The enriched culture of N.halophila LFY-1 was thermophilic and halophilic,and it could tolerate to high-temperature and high-salinity,suggesting that it has application prospects in the treatment of high-temperature and/or high-salinity wastewaters.