嗜盐石油烃降解菌Halomonas sp.1-3降解石油烃特性研究

Characteristics of petroleum degradation by the halophilic bacterium Halomonas sp.1-3

为研究嗜盐石油烃降解菌在石油烃污染修复中的应用可行性,研究了来自胜利油田油泥中的一株嗜盐石油烃降解菌Halomonas sp.1-3在不同NaCl浓度条件下的生长特性及对石油烃的降解特性。结果表明:菌株在NaCl浓度低于6%条件下培养时表现为延滞期短,快速达到稳定期后随即进入衰亡期;中高盐度(≥9%)条件下培养时延滞期延长,达到稳定期的时间滞后,但稳定期时间长。低盐条件下菌株对石油烃的降解启动快,但不持续;当NaCl浓度为5%~10%时,菌株对石油烃有长效的降解,NaCl浓度为5%时菌株对石油烃降解率最高,对C_(10)~C35不同碳数石油烃的降解率为55%~85%;当NaCl浓度大于10%时,随着NaCl浓度的升高降解率迅速降低,其中碳链较短的石油烃(C_(10)~C_(14))降解率呈明显下降趋势,而长链石油烃(C_(29)~C_(36))降解率呈上升趋势。研究表明,菌株Halomonas sp.1-3在盐碱环境中对石油烃具有良好的降解效果。

To explore the feasibility of using halophilic petroleum-degrading bacteria for the remediation of petroleum-contaminated soil,the growth and total petroleum hydrocarbon(TPH)degradation performance of a halophilic petroleum-degrading bacteria named Halomonas sp.1-3,which was selected from the Shengli Oil Field in previous research,was investigated in the present study.The strain showed a short lag phase before the stationary phase,followed by a decline phase soon when cultured at low salinity.When cultured at salinity higher than 9%,the lag phase was prolonged,and the stationary phase was delayed but more stable.The TPH degradation process started promptly but stopped quickly when cultured at low salinity conditions,while the process continued when cultured with salinity between 5%and 10%.The highest degradation rate was between 55%and 85%for different TPH components with 5%salinity.However,the degradation rate declined with increasing NaCl concentration.The degradation rate showed different trends with varied TPH components,especially with the artificially divided two groups according to their different carbon contents,C_(10)~C_(14) and C_(29)~C_(36),with the former exhibiting a declining degradation rate,while the latter showed an opposite trend with increasing NaCl concentration.The results indicated Halomonas sp.1-3 had an effective degradation effect on petroleum hydrocarbons in a saline-alkali environment.