菌株M降解硝基苯的特性及动力学研究

The Study on Characteristic and Kinetic of Nitrobenzene Biodegradation by Strain M

从受硝基苯污染的土壤筛选出能以硝基苯为唯一碳源菌株M,其最佳培养条件:pH为7,温度30℃,摇床转速200r/min,接种量10%(v/v)。在此最佳条件下,考察了菌株M对硝基苯浓度的耐受性、降解动力学、培养基的TOC和生物毒性。菌株M对硝基苯的最大耐受浓度为900mg/L。300mg/L的硝基苯经菌株M降解后的代谢产物的TOC从1400mg/L降到400mg/L,生物毒性在12h内逐渐降低直至无毒。当硝基苯浓度≤415.92mg/L时,菌株M降解硝基苯符合零级动力学方程。菌株M对硝基苯的降解也符合Andrews抑制模型,模型参数分别为qmax=60h-1,Ks=100mg/L,Ki=350mg/L。

A strain named as M,which can use nitrobenzene as a sole carbon source,was screened from the nitrobenzene contaminated soil.The optimum culture condition of stain M was pH 7,temperature 30℃,rotation speed 200 r/min and inoculated volume of M 10%（v/v）.The tolerance concentration,biodegradation kinetics,the TOC and biotoxicity of metabolite of nitrobenzene of strain M were studied under the optimum condition.The highest tolerance concentration of nitrobenzene was 900 mg/L.In the degradation process for 300 mg/L nitrobenzene,the TOC decreased from 1400 mg/L to 400mg/L and the biotoxicity of the metabolite decreased gradually till nontoxic within 12 h.The degradation kinetics of strain M was well fit with zero-level kinetic equation when the concentration of nitrobenzene was less than 415.92 mg/L.Meantime,the degradation kinetics of strain M was well fit with Andrews kinetic model with q max =60 h-1,K s =100 mg/L,K i = 350 mg/L.