一株苯酚降解菌HY-1的筛

发布时间：2018-11-23 09:36

【摘要】：本研究采用富集培养的方法,从淮安市清江石化厂的废水污泥中分离得到一株能够高效降解苯酚的菌株,命名为HY-1。对菌株HY-1进行了生理特性研究,采用PCR方法扩增其16S r RNA基因序列,并进行测定。结果表明,菌株HY-1可以在以苯酚为唯一碳源的无机培养基上生长,对苯酚具有较强的降解能力。该菌株的16S r DNA序列与不动杆菌Acinetobacter sp.的序列相似度均在97%以上,与Acinetobacter beijerinckii(Accession FN433036)的亲缘关系最近,结合形态特征、生理特性以及系统发育分析,将其初步鉴定为Acinetobacter sp.HY-1。考察了菌株HY-1生长及降解苯酚的基本特性,测定不同的苯酚初始质量浓度、温度、p H值、装液量及外加盐浓度对该菌生长及降解苯酚能力的影响。结果表明,在35°C,p H为7.5,装液量为50m L,接种量为20%,摇床振荡速度120r/min的条件下,培养6h后可使500mg/L的苯酚降解率达到95%以上,高浓度的外加盐对该菌生长和降酚能力均有较大抑制作用,固定化微生物技术提高了苯酚降解率。采用湿法加工对凹土进行提纯,再进行热改性、酸改性和有机改性制备改性凹土,通过对改性凹土的表征,研究结构和性质变化。实验结果表明:经过酸改性与有机改性的凹土比表面积更大,有机改性凹土的亲水性更强、表面电荷分布更多。采用凹土吸附法与生物降解法相结合,利用改性凹土载体对菌株进行固定化,并对其降解含酚废水的效果进行研究。研究表明,采用吸附法将菌株固定于改性凹土载体对苯酚进行降解,降解性能最好的载体是有机改性凹土-菌种复合载体,其苯酚降解率达97%,酸改性凹土-菌种复合载体次之,其降解率达84%,而最差的是原凹土-菌种复合载体,降解率仅为61%。
[Abstract]:In this study, a high efficient phenol degrading strain was isolated from wastewater sludge of Qingjiang Petrochemical Plant in Huaian City by means of enrichment and culture, and named as HY-1.. The physiological characteristics of the strain HY-1 were studied. The 16s r RNA gene sequence was amplified by PCR, and the 16s r RNA gene was sequenced. The results showed that the strain HY-1 could grow on inorganic medium with phenol as the sole carbon source and had strong degradation ability to phenol. 16s r DNA sequence and Acinetobacter sp. of Acinetobacter spp. The sequence similarity of Acinetobacter beijerinckii (Accession FN433036 was over 97%, and its relationship with Acinetobacter beijerinckii (Accession FN433036 was the most recent. Combined with morphological characteristics, physiological characteristics and phylogenetic analysis, it was preliminarily identified as Acinetobacter sp.HY-1.. The basic characteristics of the growth and degradation of phenol by HY-1 were investigated. The effects of different initial concentration of phenol, p H value of temperature, the amount of solution and the concentration of added salt on the growth and degradation of phenol were determined. The results showed that the phenol degradation rate of 500mg/L could reach more than 95% under the conditions of 35 掳C ~ (-1) pH = 7.5, 50 mL liquid loading, 20 inoculum and 20 shaking speed 120r/min. After 6 hours of culture, the phenol degradation rate of 500mg/L was more than 95%. High concentration of external salt inhibited the growth and the ability of reducing phenol, and the immobilized microorganism technology improved the degradation rate of phenol. The modified attapulgite was prepared by wet processing, thermal modification, acid modification and organic modification. The change of structure and properties of the modified attapulgite was studied through the characterization of the modified attapulgite. The experimental results show that the surface area of acid-modified and organic modified attapulgite is larger, the hydrophilicity and surface charge distribution of organically modified attapulgite are stronger. A modified attapulite carrier was used to immobilize the strain and its effect on the degradation of phenolic wastewater was studied by combining the adsorption of attapulite with the biodegradation method. The results showed that the best carrier for degradation of phenol was organic modified attapulgite, and the degradation rate of phenol was 97%. The degradation rate of acid-modified attapulgite-strain compound carrier was 84%, while the worst was the original attapula-strain compound carrier, the degradation rate was only 61%.
【学位授予单位】：西南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X703;X172

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