一株异养硝化-好氧反硝化细菌的分离鉴定及脱氮活性研究

从杭州市天子生活岭垃圾填埋垃圾渗滤液调节池周围土壤样品中分离到一株异养硝化-好氧反硝化细菌ZB612,通过形态学观察及16S rDNA同源性分析,初步鉴定属于根瘤菌属(Rhizobium sp.).随后研究了该菌株的脱氮能力,结果表明在初始氨氮浓度为100mg/L异养硝化培养基中,氨氮的去除效率达到90%,未出现明显的硝态氮和亚硝态氮积累,具有同步硝化反硝化特征;在亚硝酸盐反硝化体系中,亚硝态氮的去除效率达到60%.除此还考察了四种单因素 (温度、pH值、碳氮比和碳源种类) 分别对菌株ZB612脱氮效率的影响:该菌株的最佳脱氮条件为温度30℃,初始pH=7,C/N=8,以葡萄糖作为最适碳源.

Isolation and identification of a heterotrophic nitrification-aerobic denitrification bacterium and its denitrification ability

A bacterium ZB612 with heterotrophic nitrification-aerobic denitrification was isolated from soil sample around leachate regulating pool of Hangzhou Tianziling waste landfill. The strain ZB612 was preliminary identified as Rhizobium sp. by morphology and 16S rDNA homology analysis. We subsequently studied its denitrification ability, the results showed that the ammonia nitrogen removal efficiency reached 90% in the heterotrophic nitrification medium with initial ammonia nitrogen concentration of 100mg/L. Meanwhile, the obvious accumulation of nitrate-N and nitrite-N did not appeared, which is the characteristics of simultaneous nitrification and denitrification (SND). In nitrates denitrification system,the nitrate nitrogen removal efficiency could reach 60%. In addition, we investigated the effect of four factors (including temperature, pH, carbon nitrogen ratio and carbon source) on denitrification efficiency of the strain ZB612, respectively. The optimum denitrification conditions were found to be as follows: temperature of 30℃, the initial pH of 7, C/N ratio of 8, where the optimal carbon resource was glucose.