1株脱氮除磷菌的筛选及其特性研究

采用YG培养基,结合蓝白斑筛选、异染粒染色及好氧除磷能力检测等实验,从城市生活污水处理厂好氧生化池的活性污泥中分离出7株好氧除磷菌;再经硝酸盐还原产气和缺氧培养实验,筛选出1株高效脱氮除磷菌;通过16S rRNA基因同源性比较和生理生化鉴定,初步将其鉴定为Pseudomonas grimontii,命名为C18.菌株C18在好氧培养24h后,培养基中上清液磷浓度从38.7mg/L降低到2.28mg/L,除磷率达94.1%.C18在缺氧培养24h后,培养基中上清液磷浓度从44.5mg/L降低到5.21mg/L,除磷率达88.3%;上清液硝酸盐氮浓度从184.2mg/L降低到30.6mg/L,脱氮率达83.4%.菌株C18最适脱氮除磷温度为30℃;最适脱氮除磷pH为7.5.

Selection of Denitrifying Phosphorus-Removing Bacteria and Its Characteristic

Using YG culture medium, combined with the experiments of blue-and white-colored screening, Albert staining and detection of phosphorus removal capacity, seven phosphorus-removing bacterium were isolated from activated sludge collected from aerobic biochemical pool of wastewater treating factory. After nitrate reducing and anoxic culturing experiment, a strain with high capability of denitrifying and phosphorus removing was selected. With the study of its physiology and biochemistry and the analysis of its 16S rRNA gene, this strain was identified as Pseudomonas grimontii, and named of C18. The phosphorus removal rate of C18 was 94.1% under aerobic condition in 24 hours (The phosphorus concentration in supernatant was 38.7 mg/L to 2.28 mg/L). The phosphorus removal rate of C18 was 88.3% under anoxic condition in 24 hours (the phosphorus concentration in supernatant was 44.5 mg/L to 5.21 mg/L), and the denitrifying rate of C18 was 83.4% under anoxic condition in 24 hours (the nitrate concentration in supernatant was 184.2 mg/L to 30.6 mg/L). The optimal temperature of C18 denitrifying and phosphorus removing was 30 degrees C; The optimal pH of C18 denitrifying and phosphorus removing was 7.5.