DBP降解菌株XJ1的分离鉴定及其降解特性  

Isolation and Identification of DBP-Degrading Strain XJ1 and Its Degradation Characters

作　　者：周洪波[1] 胡培磊[1] 刘飞飞[1] 谢英剑[1] 李莹[1] 任洪强[2] 

机构地区：[1]中南大学资源加工与生物工程学院,湖南长沙410083 [2]南京大学污染控制与资源化研究国家重点实验室,江苏南京210093

出　　处：《生物技术》2008年第2期64-67,共4页Biotechnology

基　　金：国家自然科学基金项目资助(406460029);南京大学污染控制与资源化研究国家重点实验室开放基金课题(PCRRF06002)

摘　　要：目的:从湘江底泥筛选分离出能够高效降解邻苯二甲酸二丁酯(DBP)的菌株,对其进行鉴定和降解特性研究。方法:采用DBP为唯一碳源和能源的无机盐培养基,通过富集培养、平板划线分离得到一株优势菌,编号为XJ1。采用形态学、生理生化、(G+C)mol%和16SrDNA序列分析进行鉴定。采用高效液相色谱测定菌株XJ1在摇瓶中对DBP的降解能力,并进行DBP代谢产物的分析和底物广谱性测试。结果:鉴定该菌株为Sphingomonsasp.。摇瓶实验结果表明:最佳降解条件为温度35℃,初始pH为7.0,转速150r/min;在最佳的降解条件下,40h之内DBP可完全降解。HPLC-UV检测出的中间代谢产物为邻苯二甲酸单丁酯(MBP)和邻苯二甲酸(PA)。底物广谱性实验表明菌株XJ1能够利用邻苯二甲酸二甲酯、邻苯二甲酸二乙酯等邻苯二甲酸酯类化合物。结论:菌株XJ1对DBP具有高效的降解能力,在处理含有邻苯二甲酸酯类化合物污染的生物修复方面具有独特的应用潜力。Objective：A di-n-butyl phthalate-degrading bacterium was isolated from Xiangjiang River sediment,then the bacterium was identified and its degrading capability was studied.Method：Utilizing DBP as the sole carbon and energy source,a predominated bacterium,designated as strain XJ1,was isolated by enrichment culture and streak plate method.The strain XJ1 was identified based on 16S rDNA sequence analysis,（G＋C） mol % and its morphological and physiological characteristics.The biodegradation experiments of DBP were performed in shake flasks and its DBP degradation capability was measured by high performance liquid chromatography,diversity of degradable substrates was also tested.Result：Strain XJ1 was identified as Sphingomonas sp.The optimum conditions for DBP degradation by strain XJ1 were initial pH 7.0,35 ℃ and agitation rate being 150 r/min.In 40h,DBP was degraded completely under the optimum conditions,the DBP metabolites detected by HPLC-UV were mono-butyl phthalate（MBP） and phthalate acid（PA）.Diversity of degradable substrates showed that phthalate esters such as dimethyl phthalate,diethyl phthalate,etc.could be used by stain XJ1.Conclusion：DBP could be degraded effectively by strain XJ1,and the strain XJ1 had special application potential on bioremediation for phthalate esters contaminated site.

关 键 词：邻苯二甲酸二丁酯 鞘氨醇单胞菌 分离鉴定 生物降解 生化途径 底物广谱性 

分 类 号：Q93-331[生物学—微生物学]