一株好氧反硝化菌的筛选鉴定及其脱氮特性研究 Identification and Denitrification Characteristics of an Isolated Aerobic Denitrifier

本研究从巴陵石化己内酰胺污水中分离高效好氧反硝化菌，并对菌株的反硝化特性进行研究。通过BTB培养基初筛及菌株硝酸盐的降解实验，从样品中分离得到一株脱氮性能最好的好氧反硝化菌，结合其生理生化特性和16S rDNA测序结果，对菌株进行鉴定。研究不同碳源、C/N、温度及pH对其反硝化能力的影响。筛选得到高效好氧反硝化菌B-5，经鉴定属于假单胞菌属(Pseudomonas sp.)。降解特性研究表明，当碳源为琥珀酸钠或乙酸钠，C/N为15:1，温度为30℃~35℃，pH为6~7时，菌株B-5的降解性能最佳。 This study aimed at the isolation of an aerobic denitrifier with high nitrogen removal ability from caprolactam sewage and its denitrifying characteristics. An aerobic denitrifier with the best deni-trifying performance was isolated from the sample by BTB medium preliminary screening and ni-trate degradation analysis. We used morphological and physiological characteristics as well as its 16S rDNA sequences to identify the strain. Effects of culture conditions, such as carbon sources, C/N ratio, temperature and initial pH, were evaluated regarding denitrifying capacity under aerobic condition. The highly effective strain B-5 was identified as Pseudomonas sp. Studies of degradation characteristics showed that the most efficient nitrate removal rate for B-5 occurred at C/N = 15 when sodium succinate or sodium acetate was supplemented as the carbon source. The optimum temperature for B-5 was 30˚C - 35˚C and optimum pH ranged from 6 to 7.