The Alkali-Tolerant Bacterium of Bacillus thuringiensis EM-A1 Can Effectively Perform Heterotrophic Nitrification and Aerobic Denitrification
The Alkali-Tolerant Bacterium of Bacillus thuringiensis EM-A1 Can Effectively Perform Heterotrophic Nitrification and Aerobic Denitrification
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DOI：
10.3389/fenvs.2021.818316
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发表时间：
2022-01
期刊：
影响因子：
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通讯作者：
Tingjiang Wang;Mengping Chen;Xiwen Liang;Fangling Chen;T. He;Zhuchilin Li
中科院分区：
文献类型：
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作者：
Tingjiang Wang;Mengping Chen;Xiwen Liang;Fangling Chen;T. He;Zhuchilin Li
羟胺脱氮可有效提高废水处理效率。本研究以羟胺为唯一氮源，从沼气池中获得苏云金芽孢杆菌EM-A1菌株。在30°C、蔗糖为碳源、碳氮比为40、转速为0 rpm、pH值为9.58、接种量为0.58×108菌落形成单位的条件下，羟胺和总氮的去除率分别为100%和71.86%。菌株EM-A1能完全消耗氨氮，在脱氮过程中产生8.32 ± 0.08 mg/L的硝酸盐。在好氧反硝化过程中，菌株EM-A1对NO2 −-N和NO3 −-N的去除率分别为100%和76.67%。当NH 4+、NO3-和NO2-分别作为唯一氮源时，初始总氮以含氮气体形式损失的比例分别为29.34 ± 0.18%、26.71 ± 0.36%和23.72 ± 0.88%。氨单加氧酶、羟胺氧化还原酶、硝酸还原酶和亚硝酸氧化还原酶的比活力分别为0.37、0.88、0.45和0.70 U/mg蛋白。这些结果表明，B.苏云金杆菌EM-A1是一种很有前途的废水无机氮生物修复候选菌株。
Removal of nitrogen from hydroxylamine could effectively improve the wastewater treatment efficiency. In this work, Bacillus thuringiensis EM-A1 was obtained from a biogas digester with hydroxylamine as the only nitrogen source. Hydroxylamine (100%) and total nitrogen (71.86%) were efficiently removed under the following conditions: 30°C, sucrose as carbon source, carbon to nitrogen ratio 40, rotation speed 0 rpm, pH 9.58, and inoculant concentration of 0.58×108 colony-forming units. Ammonium was completely consumed by strain EM-A1, and 8.32 ± 0.08 mg/L of nitrate was produced during the ammonium removal process. During aerobic denitrification, the removal efficiencies of NO2 −-N and NO3 −-N by strain EM-A1 were 100 and 76.67%, respectively. There were about 29.34 ± 0.18%, 26.71 ± 0.36%, and 23.72 ± 0.88% initial total nitrogen lost as nitrogenous gas when NH4 +, NO3 −, and NO2 − were separately used as the sole nitrogen source. The specific activities of ammonia monooxygenase, hydroxylamine oxidoreductase, nitrate reductase, and nitrite oxidoreductase were successfully detected as 0.37, 0.88, 0.45, and 0.70 U/mg protein, respectively. These results indicated that B. thuringiensis EM-A1 is a promising candidate for bioremediation of inorganic nitrogen from wastewater.