Luo Wensui, D'Angelo Elisa M, Coyne Mark S
Soil and Water Biogeochemistry Laboratory, Plant and Soil Sciences Department, University of Kentucky, Lexington, KY 40546, United States.
Chemosphere. 2008 Jan;70(3):364-73. doi: 10.1016/j.chemosphere.2007.07.022. Epub 2007 Sep 17.
Certain organic compounds, including biphenyl and salicylic acid, stimulate polychlorinated biphenyl (PCB) degradation by microorganisms in some environments. However, the usefulness of these amendments for improving PCB removal by microorganisms from diverse habitats has not been extensively explored. This study evaluated the effects of biphenyl, salicylic acid, and glucose on changes in aerobic PCB removal and bacterial communities from an agricultural soil, a wetland peat soil, a river sediment, and a mixture of these samples. PCB removal patterns were significantly different between soils and sediments amended with carbon compounds: (i) terrestrial soil microorganisms removed more PCBs than river sediment microorganisms, particularly with regard to PCBs with >4 chlorine substituents, (ii) glucose-supplemented, agricultural soil microorganisms removed more hexachlorobiphenyl than unsupplemented samples, (iii) biphenyl-supplemented, river sediment microorganisms removed more di- and tri-chlorobiphenyls than unamended samples. Carbon amendments also caused unique shifts in soil and sediment bacterial communities, as determined by specific changes in bacterial 16S rRNA denaturing gradient gel electrophoresis banding patterns. These results indicate that organic carbon amendments had site-specific effects on bacterial populations and PCB removal. Further work is needed to more accurately characterize PCB degrading communities and functional gene expression in diverse types of environments to better understand how they respond to bioremediation treatments.
某些有机化合物，包括联苯和水杨酸，在某些环境中能刺激微生物对多氯联苯（PCB）的降解。然而，这些添加物对于提高不同生境中微生物对PCB的去除效果尚未得到广泛研究。本研究评估了联苯、水杨酸和葡萄糖对来自农业土壤、湿地泥炭土、河流沉积物以及这些样品混合物的需氧PCB去除和细菌群落变化的影响。用碳化合物改良的土壤和沉积物之间的PCB去除模式存在显著差异：（i）陆地土壤微生物去除的PCB比河流沉积物微生物更多，特别是对于氯取代基大于4的PCB；（ii）添加葡萄糖的农业土壤微生物去除的六氯联苯比未添加的样品更多；（iii）添加联苯的河流沉积物微生物去除的二氯和三氯联苯比未改良的样品更多。通过细菌16S rRNA变性梯度凝胶电泳条带模式的特定变化确定，碳添加物也导致了土壤和沉积物细菌群落的独特变化。这些结果表明，有机碳添加物对细菌种群和PCB去除具有特定地点的影响。需要进一步开展工作，以更准确地表征不同类型环境中PCB降解群落和功能基因表达，从而更好地了解它们对生物修复处理的反应。
