Borja J Q, Auresenia J L, Gallardo S M
Asian Regional Research Programme on Environmental Technology, National Research Institute on Industrial and Hazardous Wastes, De La Salle University, College of Engineering, 2401 Taft Avenue, Manila 1004, Philippines.
Chemosphere. 2006 Jul;64(4):555-9. doi: 10.1016/j.chemosphere.2005.11.047. Epub 2006 Jan 9.
This study investigated the use of biofilms in the biodegradation of polychlorinated biphenyls. The biofilm used was developed on modified cement particles using mixed microbial culture isolated from PCB-contaminated soil. The biofilm formed was first acclimatized to PCBs by feeding the reactor alternately with biphenyl and PCBs. The acclimatized biofilm was tested on simulated PCB-contaminated water containing Aroclor 1260 by using a three-phase fluidized-bed reactor operated in batch mode. The initial batch run yielded 80+/-2.38% PCB removal from medium in one day and 91+/-1.34% in 5 days. The percent PCB removal gradually increased in the succeeding runs reaching 92+/-2.48% in one day and a steady state value of 95+/-2.01% in 5 days from batch eight onwards. PCB removal from the medium was highest during the first day reaching 80-92%. The sudden decrease in PCB concentration was attributed to an initial adsorption of the PCB on the biofilm and then the compound was degraded gradually. Yellow intermediates were observed as the pH of the medium decreased. These intermediate products were further metabolized as indicated by the disappearance of the yellow substance.
本研究调查了生物膜在多氯联苯生物降解中的应用。所使用的生物膜是利用从多氯联苯污染土壤中分离出的混合微生物培养物在改性水泥颗粒上形成的。通过在反应器中交替投喂联苯和多氯联苯，使形成的生物膜首先适应多氯联苯。利用以间歇模式运行的三相流化床反应器，对含有Aroclor 1260的模拟多氯联苯污染水进行了适应后的生物膜测试。初始批次运行在一天内从培养基中去除了80±2.38%的多氯联苯，5天内去除了91±1.34%。在后续运行中，多氯联苯的去除率逐渐增加，从第八批开始，一天内达到92±2.48%，5天内达到稳定状态值95±2.01%。从培养基中去除多氯联苯在第一天最高，达到80 - 92%。多氯联苯浓度的突然下降归因于多氯联苯最初吸附在生物膜上，然后该化合物逐渐降解。随着培养基pH值的降低，观察到黄色中间体。这些中间产物如黄色物质的消失所示进一步被代谢。
