好氧堆肥微生物降解土壤中硝基苯的影响因素研究

INFLUENCING FACTORS ON AEROBIC MICROBIAL DEGRADATATION NITROBENZENE IN SOIL BY BIO-COMPOST

为进一步了解好氧堆肥降解土壤硝基苯的机理,从堆肥高温期筛选出能以硝基苯为唯一碳源和氮源的微生物,并研究了该菌系降解硝基苯的最佳条件。发现该微生物不能以葡萄糖作为共代谢底物,在p H值为5,当硝基苯初始浓度为25 mg/L时,生长情况最佳,且降解时间最短为84 h,对于100 mg/L的硝基苯最快96 h能完全降解。通过16s r DNA对该菌系进行鉴定表明,该微生物为粪产碱杆菌和戴尔福特菌,硝基苯降解途径为好氧条件下的JS765氧化途径。采用该微生物体系接种到硝基苯污染的土壤中,相比不接种处理组的硝基苯降解率提高了10%左右。

To further understand the mechanism of nitrobenzene in soil degradation in aerobic compost,we studied the optimum conditions of nitrobenzene degradation bacteria,which was screened from the high temperature stage of the compost and could use nitrobenzene as the sole carbon source and nitrogen source. This microorganism can not consume glucose as a co-metabolism substrate. The optimal growth condition of this microorganism was p H at 5 and the initial concentration of nitrobenzene at 25 mg / L. Then the degradation time was shortened to 84 h,100 mg / L nitrobenzene can be completely degraded in 96 h. The 16 s r DNA of strain identification system showed that the microbe is Alcaligenes and Delft bacteria,the nitrobenzene degradation under aerobic condition follows the JS765 oxidation pathway. The degradation rate of nitrobenzene contaminated soil can be improved by 10% if inoculating this microorganism into the soil.