Kumar Vinay, Sharma Neha, Maitra S S
School of Biotechnology, Jawaharlal Nehru University, Lab no. 117, New Delhi, 110067, India.
Arbro Pharmaceuticals Pvt Ltd., New Delhi, 110015, India.
Biotechnol Rep (Amst). 2017 Apr 28;15:1-10. doi: 10.1016/j.btre.2017.04.002. eCollection 2017 Sep.
Dibutyl phthalate is (DBP) the top priority toxicant responsible for carcinogenicity, teratogenicity and endocrine disruption. This study demonstrates the DBP degradation capability of the two newly isolated bacteria from municipal solid waste leachate samples. The isolated bacteria were designated as sp. V21b and sp. 51F after scanning electron microscopy, transmission electron microscopy, Gram-staining, antibiotic sensitivity tests, biochemical characterization, 16S-rRNA gene identification and phylogenetic studies. They were able to grow on DBP, benzyl butyl phthalate, monobutyl phthalate, diisodecyl phthalate, dioctyl phthalate, and protocatechuate. It was observed that sp. V21b was more efficient in DBP degradation when compared with sp. 51F. It degraded 57% and 76% of the initial DBP in minimal salt medium and in DBP contaminated samples respectively. Kinetics for the effects of DBP concentration on sp. V21b and sp. 51F growth was also evaluated. Stoichiometry for DBP degradation and biomass formation were compared for both the isolates. Two major metabolites diethyl phthalate and monobutyl phthalates were identified using GC-MS in the extracts. Key genes were amplified from the genomes of sp. V21b and sp. 51F. DBP degradation pathway was also proposed.
邻苯二甲酸二丁酯（DBP）是导致致癌性、致畸性和内分泌干扰的首要有毒物质。本研究展示了从城市固体垃圾渗滤液样本中新分离出的两种细菌对DBP的降解能力。经过扫描电子显微镜、透射电子显微镜、革兰氏染色、抗生素敏感性测试、生化特性分析、16S - rRNA基因鉴定和系统发育研究后，分离出的细菌分别被命名为V21b菌和51F菌。它们能够在DBP、邻苯二甲酸苄丁酯、邻苯二甲酸单丁酯、邻苯二甲酸二异癸酯、邻苯二甲酸二辛酯和原儿茶酸上生长。观察发现，与51F菌相比，V21b菌在DBP降解方面更高效。在基本盐培养基和DBP污染样本中，它分别降解了初始DBP的57%和76%。还评估了DBP浓度对V21b菌和51F菌生长的动力学影响。比较了两种菌株DBP降解和生物量形成的化学计量关系。使用气相色谱 - 质谱联用仪（GC - MS）在提取物中鉴定出两种主要代谢产物邻苯二甲酸二乙酯和邻苯二甲酸单丁酯。从V21b菌和51F菌的基因组中扩增出关键基因。还提出了DBP降解途径。
