通过对长期受石油污染的土著菌进行培养驯化,分离筛选得到适宜降解甲基叔丁基醚(MTBE)的菌株,经其形态特征和生理生化特征,并结合16S rDNA测序分析,鉴定该菌株为产酸克雷伯菌(Klebsiella oxytoca).采用摇瓶振荡法,利用该菌株对MTBE的好氧强化降解规律进行了研究,包括MTBE降解过程中溶解氧(DO)变化及菌体生长情况,不同DO值和共存基质对MTBE降解的影响.结果表明,MTBE受初始DO值影响较大,提高受污系统溶解氧含量可强化MTBE的生物降解进程;相比于苯和甲苯对MTBE降解的抑制作用,乙醇的存在可促进MTBE的生物降解,其降解率由50%提高至60%以上.
A degradation strain for methyl tert-butyl ether(MTBE) has been isolated and acclimatized from soil contaminated by petrochemicals,which has been identified preliminarily as Klebsiella oxytoca based on its morphological properties,biochemical properties and 16S rDNA sequence analysis.The law of aerobic augmented MTBE biodegradation by this strain has been analyzed with flask shaking method,including the variation of dissolved oxygen(DO)level and the growth of bacteria in MTBE degradation,and the effect of DO concentration and coexisting compounds on MTBE degradation.Analysis results indicate that the initial DO concentration has much effect on MTBE concentration,which can be augmented by raising the initial DO level in the contaminated system.Compared with the inhibition of benzene and toluene on MTBE degradation,the existence of ethanol can enhance the efficiency of MTBE biodegradation from 50% to above 60%.