一株邻苯二甲酸二丁酯和邻苯二甲酸二(2-乙基己基)酯降解菌的筛选鉴定与降解特性

为了进一步研究土壤中主要邻苯二甲酸酯(PAEs)污染物的微生物修复,选择邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二(2-乙基己基)酯(DEHP)作为目标污染物,采用富集驯化法从设施菜地土壤中筛选出一株可同时降解邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二(2-乙基己基)酯(DEHP)的细菌AS001。通过形态、生理生化特征、16S rDNA序列分析,初步鉴定为节杆菌属(Arthrobacter sp.),重点考察了该菌株在不同转速、pH、初始浓度、接菌量和温度条件下对邻苯二甲酸酯的降解特性。结果表明,菌株AS001的最佳降解条件为:转速175 r·min^-1,pH 7.0,初始浓度100 mg·L^-1,接菌量4%,温度35 ℃,且不同条件下菌株对DBP的降解效果高于对DEHP的降解效果。为该区域土壤中PAEs污染修复的环境条件提供一定的理论依据。

Isolation,identification and degradation characteristics of a dibutyl phthalate and di-(2-ethylhexyl) phthalate degrading bacterium

In order to further study the microbial remediation of major PAEs pollutants in soil, a strain, named as AS001, capable of simultaneously degrading dibutyl phthalate (DBP) and Di-(2-ethylhexyl) phthalate (DEHP) was isolated from facility vegetable soil by culture enrichment method. The strain could utilize DBP and DEHP as the sole source of carbon and energy. Based on the morphology, physiological characteristic and 16S rDNA sequence analysis, AS001 was identified as Arthrobacter sp. and the degradation characteristics of phthalate acid esters were investigated under different rotating speeds, pH, initial concentrations, inoculation amount and temperature. The result showed that the optimal degradation condition of strain AS001 was: the rotation speed 175 r·min^-1, pH 7, initial concentration 100 mg·L^-1, inoculum size (V/V) 4%, temperature 35 ℃, and the degradation rate of DBP was higher than that of DEHP under different conditions. This study provided a certain theoretical basis for the environmental conditions of PAEs pollution remediation in soil in this area.