耐低温混菌降解苯系物的特性及菌种鉴定研究

以吉化双苯厂被硝基苯、苯系物（BTEX）污染的土壤为菌源,经过筛选驯化得到一组在低温条件（10℃）下可降解苯系物（BTEX）的混菌。室内研究表明,在10℃,pH=6.8,苯系物（BTEX）总质量浓度200mg·L^-1的条件下,84h后该菌对苯、甲苯、乙苯、二甲苯的降解率依次为93.2%、95.6%、91%、88.4%、对6种质量浓度的苯系物（BTEX）污染物中最难降解的苯进行降解动力学曲线模拟,当苯质量浓度小于17.48mg·L-1时,降解符合一级降解动力学,当苯的质量浓度为17.48～195.30mg·L^-1时,降解符合零级降解动力学、该混菌降解效果稳定、适应环境能力强,经80次传代后仍能保持良好的降解效果,且在6个不同地区含有不同背景组成的地下水中降解效果稳定、应用Biolog细菌自动鉴定系统和16SrDNA序列分析方法对降解率较高的3株菌B2、B4、B6作菌种鉴定,B2为嗜麦芽糖寡养单胞菌（Stenotrophomonas maltophilia）,B4为斑生假单胞菌（Pseudomonas maculicola）,B6为多刺假单胞菌（Pseudomonas spinosa）。

Investigation of biodegrading characteristics of BTEX by low-temperature-tolerated bacterial colony

The article taked the nitrobenzene and BTEX-polluted soil sample fron Jihua double benzene factory as the bacteria source, obtaining the low temperature and highly effective BTEX degrading bacteria colony by the screening and domestication. The indoor research indicated that on the condition of 10 ℃, PH=6.8, BTEX total mass concentration 200 mg.L^-1, the individual removal orB, T, E, X was 93.2%, 95.6%, 91%, 88.4% in 84 h. As we know, Benzene was the most difficult one to be degraded among the 6 kinds of BTEX. So we taked benzene to simulate degrading kinetics curve, When the initial mass concentration of benzene was less than 17.48 mg.L^-1, degradation conformed to first order degrading kinetics, When the initial mass concentration of benzene varied between 17.48-195.30 mg.L^-1, gradation conformed to zero-order degrading kinetics. The bacteria colony was very stable and adaptable, after the transfer of 80 generations, the bacteria colony＇s degrading abilities was as well as before. And the degrading abilities of the bacteria colony in 6 different ingredient ground water was still high. Biolog system and 16Sr DNA gene analysis revealed that B2 is Stenotrophomonas maltophilia, B4 is Pseudomonas maculicola, B6 is Pseudomonas spinosa.