高效异养硝化细菌Alcaligenes faecalis Ni3-1的分离及其脱氨特性研究

ISOLATION AND NH_4^+-N REMOVAL CHARACTERISTICS OF A HIGH-EFFICIENT HETEROTROPHIC NITRIFYING BACTERIUM ALCALIGENES FAECALIS Ni3-1

从生活排污渠中分离筛选出高效异养硝化菌株Ni3-1,通过形态和16S r DNA序列分析,初步鉴定为Alcaligenes faecalis。脱氨特性研究表明:Ni3-1的异养硝化作用主要发生在指数期;碳源对菌株脱氨效果影响较大,柠檬酸三钠和丁二酸钠为最佳碳源;在氨氮为10~1 000 mg/L时,Ni3-1均表现出较高的脱氨能力;Ni3-1适应能力较强,温度为25~35℃,p H为6~9,C/N为10~15时,24 h氨氮去除率均达95%以上。将Ni3-1用于处理高氨氮猪场废水,48 h氨氮去除率可达93.2%,且未检测到亚硝态氮和硝态氮的积累。总体而言,菌株Ni3-1在脱氨效率和适应能力方面具有明显优势,在污水脱氮处理中具有一定的开发利用价值。

A high-efficient heterotrophic nitrifying bacterial strain named Ni3-1 was isolated from sewage ditches. Based on morphological observation and 16 S r DNA sequence analysis,strain Ni3-1 was identified as Alcaligenes faecalis. NH+4- N removal characteristics of strain Ni3-1 was then analyzed. Results showed that heterotrophic nitrification by the strain Ni3-1occurred mainly during its logarithmic growth phase. Carbon source had an obviously effect on NH+4- N removal efficiency,and trisodium citrate and sodium succinate were the most appropriate ones. The strain exhibited appreciable heterotrophic nitrification activity when the NH+4-N concentration was in the range of 10 ~ 1 000 mg / L. Strain Ni3-1 was active over a wide range of temperatures( 25 ~ 35 ℃),p H values( 6 ~ 9) and C / N ratios( 10 ~ 25),and more than 95% of NH+4-N could be removed within 24 h under these conditions. Above all,this strain worked well when applied for pig wastewater treatment,and the NH+4-N removal ratio reached 93. 2% within 48 h. Neither of NO-2-N nor NO-3-N was detected in the treatment process.Heterotrophic nitrifier Alcaligenes faecalis Ni3-1 had high efficiency in NH+4- N removal and had potential for treating wastewater with a high NH+4-N load.