Li Xiang, Zhang Xue-Ying, Zhou Jun, Song Jun, Wang Jian-Gang, Yong Xiao-Yu, Jia Hong-Hua
College of Environment, Nanjing Tech University, Nanjing 211816, China.
College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China.
Huan Jing Ke Xue. 2018 Apr 8;39(4):1794-1803. doi: 10.13227/j.hjkx.201708243.
Polycyclic aromatic hydrocarbons (PAHs) pose a potential threat to ecosystems due to their mutagenic, carcinogenic, and teratogenic effects. Microbial degradation has been suggested as the best way to remove PAHs from contaminated environments. Screening of bacterial strains capable of efficiently degrading PAHs is the key to the bio-remediation technique. With the method of enrichment culture, the bacterial strain LX2, which can use pyrene as the sole carbon source, was isolated from sludge contaminated with PAHs. The strain was identified as ( sp. LX2) according to the results of the analyses of its morphology, physiology, and phylogeny of its 16S rDNA sequence. The degradation rate of pyrene by sp. LX2 was 32.1% after 21 days of cultivation at an initial pyrene concentration of 50 mg·L. Pyrene, 4,5-dihydro-, 2'-Hydroxypropiophenone, Phenol, and Protocatechuate were identified as the major metabolites by GC/MS analysis. Based on the identified metabolites, it was concluded that pyrene was degraded via two different routes by , namely the 'naphthalene' and the 'phthalic acid' routes.
多环芳烃（PAHs）因其致突变、致癌和致畸作用而对生态系统构成潜在威胁。微生物降解被认为是从受污染环境中去除多环芳烃的最佳方法。筛选能够有效降解多环芳烃的细菌菌株是生物修复技术的关键。采用富集培养法，从受多环芳烃污染的污泥中分离出能以芘为唯一碳源的细菌菌株LX2。根据其形态、生理分析结果以及16S rDNA序列的系统发育分析，该菌株被鉴定为（ sp. LX2）。在初始芘浓度为50 mg·L的条件下培养21天后， sp. LX2对芘的降解率为32.1%。通过GC/MS分析确定芘、4,5-二氢芘、2'-羟基苯丙酮、苯酚和原儿茶酸为主要代谢产物。基于鉴定出的代谢产物，得出结论：芘通过 以两种不同途径降解，即“萘”途径和“邻苯二甲酸”途径。
