好氧反硝化细菌WIT-1的分离鉴定及其脱氨氮特性

Identification and characteristics of aerobic denitrification strain WIT-1

为了选择和研究一种好氧反硝化细菌,从武汉工程大学苗圃分离到一株具有好氧反硝化能力的细菌并命名为WIT-1,鉴定为革兰氏阴性菌,杆状,菌落为淡黄色,结合16SrDNA序列分析结果初步鉴定菌株WIT-1为施氏假单胞菌(Pseudomonas stutzeri).初步探讨了菌株WIT-1在不同碳源种类、碳氮比、pH值、温度对菌株WIT-1脱氨氮作用的影响.结果表明,该菌去除氨氮过程中同时也能降低化学需氧量(ChemicalOxygen Demand,COD),并且不积累硝酸盐和亚硝酸盐.不同碳源种类下菌株WIT-1的脱氨氮能力从高到低顺序为:丁二酸钠、乙酸钠、蔗糖、葡萄糖、柠檬酸三钠.除氨氮和COD的最适初始pH为7.5,最适温度为30℃.菌株WIT-1在最适条件下,24h对氨氮的降解率可以达到100%,48h对COD的降解率为73.44%.

A aerobic denitrification strain was isolated from soil of nursery garden of Wuhan Institute of Technology,named as WIT-1.The strain WIT-1 was Gram negative,belonging to Bacillus,blond of bacterical colony.The result of 16S rDNA sequences showed that the strain WIT-1 was firstly identified as Pseudomonas stutzeri.The effects of different carbon sources,C/N,pH and temperature on the strain WIT-1 were detected.The results showed that the strain WIT-1 has the capability of removing ammonia and COD synchronously without accumulation of nitrate or nitrite.The comparison results of the ability to remove ammonia of the strain WIT-1 by different carbon sources showed in descending order as follow：sodium succinate,sodium acetate,sucrose,glucose,trisodium citrate.The optimum conditions for the strain WIT-1 of removing ammonia and COD were pH 7.5 and 30 ℃.In the optimum conditions,the removal rate of ammonia was 100% in 24 h,and the removal rate of COD was 73.44% in 48 h.