CTN-4降解百菌清的条件优化及动力学模型的研究

选用已筛选出的以百菌清为唯一碳源的降解菌株Pseudomonas sp. CTN-4作为百菌清降解菌.采用CCD设计试验,以响应面法优化CTN-4降解百菌清的条件,并建立了降解模型.结果表明,CTN-4降解百菌清的最优条件为:百菌清浓度为102.66mg/L,葡萄糖量为0.40%,初始pH值为7.05.在该条件下理论预测百菌清降解率可达93.89%,与在该条件下测定的实际值95.07%基本吻合.实验表明温度, pH值以及百菌清的初始浓度对百菌清的降解过程都有较大影响.百菌清的降解动力学模型与Compertz模型较为相似,可以用修饰过的Compertz模型进行拟合.

Optimization of CTN-4to chlorothalonil-degrading conditions and a kinetics model

A selection of a chlorothalonil-degrading strains was bacteria CTN-4 (Pseudomonas sp.) which had been selected and could use chlorothalonil as the sole carbon source. The objective of this study was to determine the optimum conditions for the biodegradation of chlorothalonil by Pseudomonas sp., and to establish a kinetic model to simulate the degradation process. Response surface methodology (RSM) based on CCD experimental design was employed to determine the optimum conditions. Results indicated that the optimum conditions for chlorothalonil degradation based on RSM and contour plots were as follows: concentration of glucose, 0.40% (w); initial concentration and pH of chlorothalonil were 102.66mg/L and 7.05, respectively. In addition, the predicted value of chlorothalonil degradation rate under the optimum conditions was 93.89%, which was in good agreement with the experimental result: under the optimum conditions, the degradation rate of chlorothalonil was 95.07%. Moreover, experiments show that the effects of pH, temperature and the initial substrate concentration on the degradation of chlorothalonil were obvious. And the degradation kinetics curves of chlorothalonil can be fitted by the modified Gompertz model which is similar with the process of chlorothalonil degradation.