紫外诱变选育优势好氧反硝化菌株

Breeding of aerobic denitrifier of high nitrogen-removal by UV-irradiation

采用紫外照射的方法对好氧反硝化菌株进行诱变,从中筛选出一株优势正突变菌株ZR43,并对其形态、生长条件及反硝化能力进行了研究.结果显示,相对于亲本R1,菌株ZR43对亚硝态氮的积累量大幅度降低,从75.05mg·L-1减少到17.42mg·L-1.TN去除率提高了18%.菌株形态为球菌.最佳生长条件:温度为30℃、pH为8、C/N为10、以丁二酸为最佳碳源.C/N对菌株ZR43的好氧反硝化能力影响很大,当C/N大于8时,总氮的去除率均达到32%以上.

An aerobic denitrifier was mutagenized by UV-irradiation and a high nitrogen-removal mutant was abtained, named ZR43. The morphology, optimal culture conditions and aerobic denitrification performance of strain ZR43 were investigated. The results showed that the accumulation of NO2- -N by the strain ZR43 was significantly less than that by the original strain R1. At nitrite concentrations from 75.05 mg·L^-1 to 17.42 mg·L^-1, the nitrogen removal rate was increased by 18% over R1. The figure of the strain ZR43 was global. The optimal culture conditions for maximum denitrification were： 30℃ , pH 8, C/N ratio = 10, and carbon source succinic acid. The aerobic denitrification performance of strain ZR43 was influenced mostly by the C/N ratio and the nitrogen removal rate was above 32% at C/N ratios above g.