中文摘要：

考察了波茨坦短芽孢杆菌对4-氯酚的降解特性及4-氯酚与苯酚在双底物体系中的相互作用。结果表明,波茨坦短芽孢杆菌能以4-氯酚为唯一碳源和能源,完全降解200 mg/L、250 mg/L及300 mg/L的4-氯酚所需时间分别为48 h、63 h和84 h,但该菌无法降解350 mg/L的4-氯酚,表明较高浓度的4-氯酚对细胞生长有较强的抑制作用。酶活分析表明,4-氯酚可诱导波茨坦短芽孢杆菌合成氯代邻苯二酚1,2-加氧酶并通过邻位裂解途径降解。细胞生长动力学过程符合Haldane方程,动力学参数为细胞最大比生长速μmax=0.145 h-1,半饱和系数KS=30.45 mg/L,底物抑制系数Ki=127.62 mg/L,决定系数R2=0.98。在4-氯酚和苯酚双底物降解过程中,4-氯酚的存在会抑制苯酚的降解,当4-氯酚初始质量浓度为40 mg/L时,1 400 mg/L苯酚被完全降解耗时更长,菌体优先利用苯酚作为碳源和能源,苯酚被完全降解后大部分4-氯酚才开始被降解;苯酚对4-氯酚降解的影响体现为低浓度促进和高浓度抑制,苯酚促进时质量浓度为100300 mg/L,而苯酚质量浓度高于300 mg/L会产生抑制作用,当苯酚初始质量浓度为200 mg/L时4-氯酚降解速率最大。采用Abuhamed动力学方程可以准确描述4-氯酚/苯酚双底物降解体系中细胞生长过程,苯酚对4-氯酚降解的抑制程度I1,2=1.47,4-氯酚对苯酚降解的抑制程度I2,1=2.56,决定系数R2=0.95。研究表明,4-氯酚对苯酚降解的抑制作用大于苯酚对4-氯酚。

英文摘要：

The paper is targeted at a study of the biodegrading features of 4-chlorophenol as single substrate and the interaction between phenol and 4-chlorophenol in the dual-substrate degradation system via a strain of BrevibaciUus borstelensis. The results of our study show that it is possible for Brevibacillus borstelensis to utilize 4-ehlorophenol as the sole carbon and energy source. The strain of brevibacillus borstelensis can help to degrade 200 rag/L, 250 mg/L and 300 mg/L 4-chlorophenol completely during the process of 48 h, 63 h and 84 h, respectively. However, it would fail to degrade 4-ehlorophenol with higher mass concentration of 350 mg/L due to its being stronger inhibited on the cell growth. The enzyme assay proves that it would be possible to induce chloroeatechol 1, 2-dioxygenase during the degradation process of 4- chlorophenol, which is likely to be followed by the degradation of 4-chlorophenol ortho fission. It is just for this reason that we have made an investigation of the cell growth kinetics of batch cultures by using 4-chlorophenol with various initial concentrations. At the same time, we have managed to make adequate description of Haldane kinetic model and in turn obtained the dynamic behaviors of the cell growth and the parameters which stand as μmax = 0. 145 h-1, Ks =30.45 mg/L, Ki = 127.62 mg/L respectively with the determination coefficient R2 = 0. 98. What is more, we have also found that the biodegradation of phenol has been inhibited by 4- chlorophenol, for 1 400 mg/L phenol in the presence of 4-cblorophenol has been degraded in a longer period in phenol/4-ch/orophenol dual-substrate degradation system than that with phenol alone. Moreover, we have also detected that it is preferable for the strain to utilize phenol as carbon and energy source with most of 4-chlorophenol being degraded in case of the said phenol being totally consumed. On the other hand, the presence of the low-concentrated phenol with 100- 300 mg/L can be used to serve as a carbon and energy source for BrevibaciUus bo