Characterization of a salt-tolerant bacterium Bacillus sp. from a membrane bioreactor for saline wastewater treatment  

作　　者：Xiaohui Zhang Jie Gao Fangbo Zhao Yuanyuan Zhao Zhanshuang Li 

机构地区：[1]Pathology Department, Fourth Clinical Hospital of Harbin Medical University [2]School of Material Science and Chemical Engineering, Harbin Engineering University

出　　处：《Journal of Environmental Sciences》2014年第6期1369-1374,共6页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No. 51108112);the Natural Science Foundation of Heilongjiang Province (No. E201252);the Maixin Pathology Foundation (No. m1101);the Fundamental Research Funding of Harbin Engineering University (No. HEUFT06029);the Open Project of State Key Laboratory of Urban Water Resource Environment, Harbin Institute of Technology (No. ESK201004)

摘　　要：High salt concentrations can cause plasmolysis and loss of activity of cells, but the salt-torlerant bacterium can endure the high salt concentrations in wastewater. In this research 7 salt-torlerant bacteria, which could survive in dry powder products and could degrade organic contaminants in saline wastewater, were isolated from a membrane bioreactor. The strain NY6 which showed the fastest growth rate, best property for organic matter degradation and could survive in dry powder more than 3 months was selected and characterized. It was classified as Bacillus aerius based on the analysis of the morphological and physiological properties as well as the 16S rRNA sequence and Neigh borjoining tree. The strain NY6 could survive in the salinity up to 6% and the optimal growth salinity is 2%; it belongs to a slightly halophilic bacterium. The capability of its dry powder products for COD removal was 800 mg COD/（g.day） in synthesized saline wastewater with salinity of 2%. According to salt-tolerant mechanism research, when the salinity was below 2%, the stain NY6 absorbed K~ and Na~ to maintain osmotic equilibrium, and when the salinity was above 2%, the NY6 kept its life by producing a large amount of spores.High salt concentrations can cause plasmolysis and loss of activity of cells, but the salt-torlerant bacterium can endure the high salt concentrations in wastewater. In this research 7 salt-torlerant bacteria, which could survive in dry powder products and could degrade organic contaminants in saline wastewater, were isolated from a membrane bioreactor. The strain NY6 which showed the fastest growth rate, best property for organic matter degradation and could survive in dry powder more than 3 months was selected and characterized. It was classified as Bacillus aerius based on the analysis of the morphological and physiological properties as well as the 16S rRNA sequence and Neigh borjoining tree. The strain NY6 could survive in the salinity up to 6% and the optimal growth salinity is 2%; it belongs to a slightly halophilic bacterium. The capability of its dry powder products for COD removal was 800 mg COD/（g.day） in synthesized saline wastewater with salinity of 2%. According to salt-tolerant mechanism research, when the salinity was below 2%, the stain NY6 absorbed K~ and Na~ to maintain osmotic equilibrium, and when the salinity was above 2%, the NY6 kept its life by producing a large amount of spores.

关 键 词：salt-torlerant bacterium saline wastewater bacteria Bacillus 16S rRNA 

分 类 号：X703[环境科学与工程—环境工程] Q939.124[生物学—微生物学]