Abstract: Strains with strong aerobic denitrifying ability was isolated from sediments in Erhai lake. 101 denitrifying bacteria was screened out from sediments in ten sampling points of Erhai lake through enrichment culture，and among which，1 strain with strongest denitrification ability was selected and named EH314. Test on this bacteria including contacting enzymes (catalase)，producing hydrogen sulfide and starch hydrolysis showed positive results，fermentation of glucose oxidation results showed it an oxidizing bacteria，results of producing lipase (Tween 80) test were negative； the strain EH314 was identified as Alcaligenes bacteria； bacterial denitrification capacity was measured and found to effectively degrade nitrate in water by the strain EH314, and the denitrification was under aerobic conditions.

Key words: Erhai lake, denitrifying bacteria, sediment

摘要： 自洱海十个点位的沉积物中富集筛选出101株反硝化细菌并从中筛选出1株较强反硝化能力的细菌，命名为EH314。该细菌接触酶(过氧化氢酶)试验、产硫化氢试验和淀粉水解均为阳性，葡萄糖氧化发酵实验结果为氧化菌，产脂酶(Tween 80)试验结果为阴性；初步鉴定该菌为产碱杆菌属细菌；对细菌反硝化能力进行测定发现，菌株EH314能有效地降解水体中的硝酸盐且反硝化可在有氧条件下进行。

关键词: 洱海, 反硝化细菌, 沉积物