北方人工湿地耐冷菌的分离·鉴定与降解特性研究

为探索低温条件下人工湿地中耐冷菌降解污染物的能力,对北方某人工湿地底泥中的微生物进行驯化,筛选出生长速率及降解效率最高的耐冷菌菌株,对菌株形态特征、生理生化特性以及16S rDNA序列分析鉴定,对菌株的生长特性进行研究。结果表明,从北方人工湿地底泥中分离筛选出一株耐冷菌菌株E,该菌株具有较好的污染物降解能力,当温度为8℃时,该菌株对模拟污水中的COD、总磷和氨氮的降解率分别达62.92%、56.42%和50.63%;对菌株E进行16S rDNA序列测定和同源性比较分析,经鉴定菌株E为黄假单胞菌(Pseudomonas flava);该菌株最佳的生长条件为培养时间48 h、温度16℃、pH 6.0～8.0、盐度为1%、碳源为蔗糖、氮源为蛋白胨,显示出菌株E具有一定的耐盐能力,为提高北方滨海盐碱地区人工湿地冬季污水处理效率提供了耐冷菌资源。

Isolation and Identification of Psychrotrophses at Northern Constructed Wetlands and Its Degradation Characteristics

In order to study the degradation ability of psychrotrophs collected from north constructed wetland,the strains with the highest growth rate and degradation efficiency were isolated.According to the degradation experiment of the simulated wastewater by psychrotrophs,the removal rates of COD,TP and NH3-N by strains E could all reach 62.92%,56.42% and 50.63% at 8 ℃.Physiological and biochemical tests and the 16S rDNA sequence similarity analysis indicated that strain E was similar to Pseudomonas flava;further studies showed that the appropriate range of temperature,pH and salinity value for growth of strain E was 16 ℃,pH 6.0-8.0 and 1%.Optimum carbon and nitrogen sources are sucrose and peptone.It is demonstrated that strain E has certainly salty resistant ability,psychrotrophs resources are provided to improve the sewage treating efficiency of constructed wetland in winter in northern coastal saline areas.