莫莫格湿地石油污染土壤中耐盐碱石油烃降解细菌的降解特性研究

Characteristics of saline-alkali-tolerant and petroleum hydrocarbon-degrading bacteria isolated from petroleum oil-polluted soil in Momoge wetland

原位筛选耐盐碱石油烃降解菌可以用来修复受石油污染的盐碱土壤。本研究从莫莫格湿地的石油污染土壤中,以菲(Phe)作为唯一碳源,分离出一株多环芳烃耐盐碱的Phe高效降解细菌株,通过形态学及16S rRNA基因序列分析,明确其系统发育进化地位;系统研究了该菌株对Phe的降解特性及其降解动力学,为湿地石油污染的治理提供了良好的菌种资源。研究结果表明,耐盐碱的Phe降解细菌S1-8菌株,属于盐单胞菌,命名为Halomonas sp. S1-8; Halomonas sp. S1-8降解Phe的最适盐浓度(Na Cl)为5%,p H为8. 0,温度为30℃。在盐浓度低于5%时,随着盐度的增加,菌株S1-8在盐碱胁迫下对Phe的降解动力学,符合一级降解动力学模型。菌株S1-8对盐浓度和环境酸碱度具有较广的适应范围,分别为Na Cl含量0～30%和p H 6. 0～11. 0。Halomonas sp. S1-8在湿地油田污染的生物修复中具有潜在的应用前景。

In situ screening of saline-alkali-tolerant and petroleum hydrocarbon-degrading bacteria can be used to remediate the saline-alkaline soils contaminated with petroleum.In this study,a polycyclic aromatic hydrocarbon degrading strain was isolated from the oil-contaminated soil of the Momoge wetland with phenanthrene (Phe) as the sole carbon source.The morphology and 16S rRNA gene sequence analysis were identified.The degradation characteristics and degradation kinetics of the phenanthrene strain were systematically studied,which intended to provide a good solution for the treatment of wetland petroleum pollution.The morphological and phylogenetic tree analysis indicated that the isolated strain belonged to Halomonas ,assigned as Halomonas sp.S1-8.The optimum salt concentration of strain S1-8 for Phe degradation was (NaCl)=5%,pH=8.0,temperature=30 ℃.The degradation kinetics of strain S1-8 to Phe under saline-alkali stress was in accordance with the first-order degradation kinetics model.Strain S1-8 had a wide range of adaptation to salt concentration and pH,respectively.Therefore, Halomonas sp.S1-8 has a potential application prospect in bioremediation of oil field pollution.