Lovley D R, Woodward J C, Chapelle F H
Water Resources Division, US Geological Survey, Reston, Virginia 22092.
Nature. 1994 Jul 14;370(6485):128-31. doi: 10.1038/370128a0.
Contamination of ground waters with water-soluble aromatic hydrocarbons, common components of petroleum pollution, often produces anoxic conditions under which microbial degradation of the aromatics is slow. Oxygen is often added to contaminated ground water to stimulate biodegradation, but this can be technically difficult and expensive. Insoluble Fe(III) oxides, which are generally abundant in shallow aquifers, are alternative potential oxidants, but are difficult for microorganisms to access. Here we report that adding organic ligands that bind to Fe(III) dramatically increases its bioavailability, and that in the presence of these ligands, rates of degradation of aromatic hydrocarbons in anoxic aquifer sediments are comparable to those in oxic sediments. We find that even benzene, which is notoriously refractory in the absence of oxygen, can be rapidly degraded. Our results suggest that increasing the bioavailability of Fe(III) by adding suitable ligands provides a potential alternative to oxygen addition for the bioremediation of petroleum-contaminated aquifers.
水溶性芳烃作为石油污染的常见成分，对地下水造成污染后，常常会产生缺氧环境，在此环境下芳烃的微生物降解过程缓慢。通常会向受污染的地下水中添加氧气以刺激生物降解，但这在技术上可能困难且成本高昂。不溶性三价铁氧化物在浅层含水层中普遍大量存在，是潜在的替代氧化剂，但微生物难以利用。在此我们报告，添加与三价铁结合的有机配体可显著提高其生物可利用性，并且在这些配体存在的情况下，缺氧含水层沉积物中芳烃的降解速率与有氧沉积物中的相当。我们发现，即使是在无氧条件下 notoriously refractory 的苯，也能被快速降解。我们的结果表明，通过添加合适的配体提高三价铁的生物可利用性，为石油污染含水层的生物修复提供了一种替代添加氧气的潜在方法。
