菲高效降解菌的分离鉴定及其降解废水中菲的特性研究
发布时间：2018-12-23 20:19
【摘要】：菲是一种具有三个苯环结构的多环芳烃(PAHs),化学性质稳定且疏水性强,能持久的存在于受煤、石油等化石原料污染的土壤、水体和空气中,并通过食物链向人体富集使人体细胞产生癌变。目前,微生物法修复环境中多环芳烃污染受到广泛关注,特别是多环芳烃高效降解菌的筛选成为研究的热点。因此,本研究从焦化废水处理厂回流污泥中取样,通过驯化、筛选得到一株菲高效降解菌株,通过菌株的形态观察、生理生化特性及16S rDNA序列测定对其进行鉴定,并采用响应面法优化了菌株的生长条件,同时借助GC-MS、高效液相色谱、傅里叶红外光谱等分析手段考察了菌株对菲的降解特性及降解途径。结果如下:(1)从焦化废水处理厂回流污泥中筛选出1株能以菲为唯一碳源和能源生长的高效降解细菌,命名为P-1。形态观察表明该菌株为革兰氏阳性菌,菌落呈淡黄色、圆形、边缘整齐、呈半球状高凸,表面光滑湿润;菌体较小,呈短杆状单个排列,菌体大小约为0.2~0.3×0.5~0.8μm。16S rDNA鉴定结果表明菌株P-1可能为鞘脂菌属。(2)通过单因素实验、Plackett-Burman实验、最陡爬坡实验及响应面实验优化了菌株的最佳生长条件,即温度为33℃、pH为7.3、装液量为36ml。此条件下菌株生长量预测值为0.602(OD600),验证实验生长量为0.613(OD600),实际值与预测值基本一致。(3)在菌株最佳生长条件下处理含菲废水,14d后对浓度为1000mg/L的菲的降解率达到99.99%;向废水中加入1g/L的表面活性剂Tween-80,经过6d处理,菲的降解率达到99.75%,是未添加Tween-80时降解速率的2.3倍;向培养基中加入其它多环芳烃与菲共基质,萘的加入使菌株对菲的降解率降低41.7%,蒽的加入使菲降解率提高12.65%,而三者同时存在时菲降解率降低22.82%。(4)菌株P-1能以萘、水杨酸、邻苯二酚为唯一碳源和能源生长,GC-MS和高效液相色谱分析表明,菲降解的中间产物有水杨酸和邻苯二甲酸,可推测菌株P-1对菲的降解同时具有水杨酸途径和邻苯二甲酸途径。高效液相色谱定量分析结果表明,菌株对菲的降解以水杨酸途径为主,且该途径通过邻苯二酚-2,3-双加氧酶使苯环发生间位断裂,生成2-羟基黏糠酸半醛。(5)菌株在降解菲的过程中会产生黄色色素,且随着菲降解率的增大而色度加深,根据GC-MS、傅里叶红外及紫外可见光谱分析,可推测为类胡萝卜素中的β-胡萝卜素。
[Abstract]:Phenanthrene (phenanthrene) is a polycyclic aromatic hydrocarbon (PAHs),) with three benzene rings, which has stable chemical properties and strong hydrophobicity. It can persist in soil, water and air contaminated by fossil materials such as coal, petroleum and so on. And through the food chain to enrich the human body so that human cells produce cancer. At present, microbial remediation of polycyclic aromatic hydrocarbons (PAHs) pollution in the environment has received extensive attention, especially the screening of high efficient PAHs degradation bacteria has become a hot topic. Therefore, a phenanthrene biodegradable strain was obtained from reflux sludge of coking wastewater treatment plant by domestication. The strain was identified by morphological observation, physiological and biochemical characteristics and 16s rDNA sequencing. The growth conditions of phenanthrene were optimized by response surface method, and the degradation characteristics and pathways of phenanthrene were investigated by means of GC-MS, high performance liquid chromatography and Fourier transform infrared spectroscopy. The results are as follows: (1) A highly efficient biodegradable bacterium, named P-1, was isolated from the reflux sludge of coking wastewater treatment plant and could grow with phenanthrene as the sole carbon source and energy source. Morphological observation showed that the strain was Gram-positive, the colony was yellowish, round, brim neat, hemispherical high convex, smooth and moist surface. The bacteria were small and arranged in the shape of a short rod. The size of the bacteria was about 0.2 脳 0. 5 0. 8 渭 m.16S rDNA. The results showed that the strain P-1 might be sphingomonas. (2) by single factor experiment, Plackett-Burman test, the strain P-1 might belong to sphingomonas. The optimum growth conditions of the strain were optimized by the steepest climbing test and response surface test. The temperature was 33 鈩，
本文编号：2390211
[Abstract]:Phenanthrene (phenanthrene) is a polycyclic aromatic hydrocarbon (PAHs),) with three benzene rings, which has stable chemical properties and strong hydrophobicity. It can persist in soil, water and air contaminated by fossil materials such as coal, petroleum and so on. And through the food chain to enrich the human body so that human cells produce cancer. At present, microbial remediation of polycyclic aromatic hydrocarbons (PAHs) pollution in the environment has received extensive attention, especially the screening of high efficient PAHs degradation bacteria has become a hot topic. Therefore, a phenanthrene biodegradable strain was obtained from reflux sludge of coking wastewater treatment plant by domestication. The strain was identified by morphological observation, physiological and biochemical characteristics and 16s rDNA sequencing. The growth conditions of phenanthrene were optimized by response surface method, and the degradation characteristics and pathways of phenanthrene were investigated by means of GC-MS, high performance liquid chromatography and Fourier transform infrared spectroscopy. The results are as follows: (1) A highly efficient biodegradable bacterium, named P-1, was isolated from the reflux sludge of coking wastewater treatment plant and could grow with phenanthrene as the sole carbon source and energy source. Morphological observation showed that the strain was Gram-positive, the colony was yellowish, round, brim neat, hemispherical high convex, smooth and moist surface. The bacteria were small and arranged in the shape of a short rod. The size of the bacteria was about 0.2 脳 0. 5 0. 8 渭 m.16S rDNA. The results showed that the strain P-1 might be sphingomonas. (2) by single factor experiment, Plackett-Burman test, the strain P-1 might belong to sphingomonas. The optimum growth conditions of the strain were optimized by the steepest climbing test and response surface test. The temperature was 33 鈩，
本文编号：2390211
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