Stimulation of pyrene mineralization in freshwater sediments by bacterial and plant bioaugmentation
Stimulation of pyrene mineralization in freshwater sediments by bacterial and plant bioaugmentation
复制标题
DOI：
10.1021/es050412d
复制
发表时间：
2005-08-01
影响因子：
11.4
通讯作者：
Blake, G
中科院分区：
文献类型：
--
作者：
Jouanneau, Y;Willison, JC;Blake, G
作为研究多环芳烃 (PAH) 在淡水沉积物中的归宿的一种方法，在掺有 [C-14]-芘的微观世界中检查了芘矿化。一些微观世界中种植了芦苇（芦苇）和/或接种了芘降解菌株分枝杆菌。 6PY1。 61 天期间记录的矿化率表明，芦苇促进了芘降解的显着增强，这可能是由于根部介导的氧气扩散到沉积物层中的增加所致，如原位氧化还原测量所示。在接种的微观世界中，在没有植物的情况下（8.8％）矿化达到了比有植物存在时（4.4％）更高的水平。矿化活动伴随着水溶性芘氧化产物的释放，其中最丰富的产物被确定为 4,5-联二菲酸。从植物组织（包括茎和叶）中回收芘，浓度范围为 40 至 240 微克/克干物质。植物还积累了可能源自微生物降解的标记氧化产物。接种后的芘降解菌株比未接种的微观世界中丰富35-70倍。从本地微生物区系中选择的大多数芘降解分离株被鉴定为奥非分枝杆菌菌株。总而言之，这项研究的结果表明，植物或 PAH 降解细菌增强了污染物的去除，但它们的效果不一定是累积的。
As a means to study the fate of polycyclic aromatic hydrocarbons (PAHs) in freshwater sediments, pyrene mineralization was examined in microcosms spiked with [C-14]-pyrene. Some microcosms were planted with reeds (Phragmites australis) and/or inoculated with a pyrene-degrading strain, Mycobacterium sp. 6PY1. Mineralization rates recorded over a 61 d period showed that reeds promoted a significant enhancement of pyrene degradation, which possibly resulted from a root-mediated increase of oxygen diffusion into the sediment layer, as indicated by in situ redox measurements. In inoculated microcosms, mineralization reached a higher level in the absence (8.8%) than in the presence of plants (4.4%). Mineralization activity was accompanied by the release of water-soluble pyrene oxidation products, the most abundant of which was identified as 4,5-diphenanthroic acid. Pyrene was recovered from plant tissues, including stems and leaves, at concentrations ranging between 40 and 240 mu g/g of dry mass. Plants also accumulated labeled oxidation products likely derived from microbial degradation. Pyrene-degrading strains were 35-70-fold more abundant in inoculated than in noninoculated microcosms. Most of the pyrene-degrading isolates selected from the indigenous microflora were identified as Mycobacterium austroafricanum strains. Taken together, the results of this study show that plants or PAH-degrading bacteria enhance pollutant removal, but their effects are not necessarily cumulative.