对某医药厂废水池的活性污泥进行长期驯化,分离筛选到1株在好氧条件下能以四氢呋喃(tetrahydrofuran,THF)为唯一碳源和能源生长的食油假单胞菌DT4(Pseudomonas oleovorans DT4).研究发现在初始pH值7.2、温度30℃、初始菌体浓度3.2mg/L的条件下,P.oleovorans DT4能够于14h内将5mmol/LTHF完全降解,菌体浓度达到188.6mg/L.另外,在THF完全降解后1h,最终溶液中总有机碳及无机碳浓度分别达到0mg/L和46mg/L,且培养基的pH值降至6.54,呈弱酸性,说明P.oleovorans DT4降解THF是一个彻底矿化的过程.通过摇瓶实验考察了温度、pH、供氧方式、金属离子等因素对菌株DT4降解THF性能的影响,获得其较适宜的生长和降解条件为:温度37℃、pH值7.5,自然转动供氧状态适宜菌体生长及对THF的降解,最适Mg^2+和Ca^2+浓度分别为0.80mmol/L和0.20mmol/L.研究成果对高效处理环境中的THF污染具有重要的应用价值.
A tetrahydrofuran (THF)-degrading strain Pseudomonas oleovorans DT4 was isolated from the activated sludge of a pharmaceutical plant. P. oleovorans DT4 was able to utilize THF as the sole carbon and energy source under aerobic condition. 5 mmol/L of THF could be completely degraded by 3.2 mg/L inoculums of P. oleovorans DT4 in I4 h at pH 7. 2 and 30~C , with the cells concentration increasing to 188.6 mg/L. After the complete consumption of THF, no TOC could be detected but IC reached the stable value of about 46 mg/L, with pH decreasing to 6.54, which indicated that the substance was totally mineralized by P. oleovorans DT4. The optimum conditions for THF biodegradation in shaking flasks were pH 7.5 and temperature 37℃ , respectively. Results from the oxygen control experiments revealed that the oxygen supply by shaking was the satisfactory growth condition. Additionally, as the important elements for DT4, Mg^2+ and Ca^2+ at concentrations of 0.80 mmol/L and 0. 20 mmol/L, respectively, were suitable for THF degradation. All the results contribute to the efficient bioremediation for the THF contaminated.