Sowmya M, Rejula M P, Rejith P G, Mohan Mahesh, Karuppiah Makesh, Hatha A A Mohamed
J Environ Biol. 2014 Jul;35(4):655-60.
Microorganisms which can resist high concentration of toxic heavy metals are often considered as effective tools of bioremediation from such pollutants. In the present study, sediment samples from Vembanad Lake were screened for the presence of halophilic bacteria that are tolerant to heavy metals. A total of 35 bacterial strains belonging to different genera such as Alcaligenes, Vibrio, Kurthia, Staphylococcus and members of the family Enterobacteriaceae were isolated from 21 sediment samples during February to April, 2008. The salt tolerance and optimum salt concentrations of the isolates revealed that most of them were moderate halophiles followed by halotolerant and extremely halotolerant groups. The minimum inhibitory concentrations (MICs) against cadmium and lead for each isolate revealed that the isolates showed higher MIC against lead than cadmium. Based on the resistance limit concentration, most of them were more tolerant to lead than cadmium at all the three salt concentrations tested. Heavy metal removal efficiency of selected isolates showed a maximum reduction of 37 and 99% against cadmium and lead respectively. The study reveals the future prospects of halophilic microorganisms in the field of bioremediation.
能够耐受高浓度有毒重金属的微生物通常被视为从这类污染物中进行生物修复的有效工具。在本研究中，对韦姆巴纳德湖的沉积物样本进行了筛选，以寻找耐受重金属的嗜盐细菌。2008年2月至4月期间，从21个沉积物样本中总共分离出35株属于不同属的细菌菌株，如产碱菌属、弧菌属、库特氏菌属、葡萄球菌属以及肠杆菌科成员。分离菌株的耐盐性和最佳盐浓度表明，它们中的大多数是中度嗜盐菌，其次是耐盐和极端耐盐菌群。每个分离菌株对镉和铅的最低抑菌浓度（MIC）表明，分离菌株对铅的MIC高于镉。基于抗性极限浓度，在所有测试的三种盐浓度下，它们中的大多数对铅的耐受性都高于镉。所选分离菌株的重金属去除效率显示，对镉和铅的最大去除率分别为37%和99%。该研究揭示了嗜盐微生物在生物修复领域的未来前景。
