1株高效BBP降解菌的分离与特性研究

Isolation and Characterization of a Highly Efficient BBP-degrading Bacterium

从湖北省荆沙河泥样中富集培养分离得到了1株能够以邻苯二甲酸丁基苄基酯为唯一碳源和能源生长的细菌并命名为HS-B1.采用形态学、生理生化和16S rDNA序列分析对其进行了鉴定,发现HS-B1是1株杆状、需氧、革兰氏阴性细菌,接触酶呈阳性反应,氧化酶呈阴性反应,不产硫化氢气体,且该菌的16S rDNA序列与琼氏不动杆菌(Acinetobacter junii)的相似性高达99%.因此初步鉴定该菌株为不动杆菌(Acinetobacter sp.).摇瓶实验表明,菌株HS-B1生长和BBP降解的最适培养条件为35℃,pH 8.0.采用0.10 mmol.L-1非离子型表面活性剂吐温-80提高了BBP在水溶液中的表观溶解度,发现在最适培养条件下,HS-B1能够在48 h内将浓度为1 000 mg.L-1BBP完全降解,证明是一株高效降解菌.底物广谱性实验中,菌株HS-B1也能够有效利用DMP、DEP、DBP等邻苯二甲酸酯类化合物,说明该菌株在处理邻苯二甲酸酯类化合物的污染治理中有独特的应用潜力.

A bacterial strain HS-B1 which can utilize n-butyl benzyl phthalate as the sole source of carbon and energy was isolated from contaminated sludge in the Jinsha River of Hubei Province. Based on its morphology, physiological characteristic and 16S rDNA sequence analysis,HS-B1 was identified as Acinetobacter sp.. Shake flask experiments indicated the optimum pH, temperature for growth and BBP biodegradation by HS-B1 was found to be 8.0 and 35℃ , respectively. When using O. 10 mmol. L^-1 non-ionic surfactant Tween-80 as co-solvent to increase the apparent solubility of BBP in water, HS-B1 was able to completely degrade 1 000 mg.L^-1 BBP within 48 hours. Diversity of degradable substrates also showed that HS-B1 can efficiently utilize many other phthalate esters such as dimethyl phthalate and diethyl phthalate. It revealed that the strain HS-B1 has special application potential in dealing with the pollution caused by phthalate esters.