氯苯类混合物生物降解过程中的动力学与相互作用研究

Kinetics and interaction of chlorobenzene mixtures in the process of biodegradation

氯苯类混合物的生物降解往往受限于组分间复杂的相互作用.本研究筛选了一株可同时高效降解氯苯(CB)和邻二氯苯(o-DCB)的假单胞菌HY-100A,并应用SKIP模型,建立了CB和o-DCB生物降解的动力学模型.同时,结合MATLAB常微分方程求解器,首次定量分析了它们的相互作用.通过比较不同条件下的相互作用参数I_(2,1)和I_(1,2),发现两种化合物之间存在相互抑制作用,且随o-DCB浓度的提高而增强;o-DCB对CB降解的抑制作用显著弱于CB对o-DCB降解的抑制作用.经物料衡算和冗余分析,得出了2-氯酚和2-氯对苯二酚浓度在CB和o-DCB相互抑制过程中的演变规律,推测氯酚类物质的积累可能是CB和o-DCB的生物降解相互抑制的重要原因.

The biodegradation efficiency of chlorobenzene mixtures is often limited by the complex interactions of components.This study isolated a novel strain Pseudomonas sp.HY-100A,which can simultaneously degrade chlorobenzene(CB)and o-dichlorobenzene(o-DCB)with high efficiency.The kinetic model of CB and o-DCB biodegradation was established based on the SKIP model.The interaction between CB and o-DCB was first quantitatively analyzed by MATLAB ordinary differential equation solver.Comparing the change of interaction parameters I_(2,1) and I_(1,2) at different conditions,it discovered that the mutual inhibition of CB and o-DCB existed and enhanced with the increase of o-DCB concentration.However,the inhibition of o-DCB on CB degradation was significantly lower than that of CB on o-DCB degradation.Accordingly,the production change of 2-chlorophenol and 2-chlorohydroquinone was elucidated by both mass balance and redundancy analysis.It could be inferred that the accumulation of chlorophenols played an important role for the mutual inhibition of CB and o-DCB biodegradation.