Corporate R&D, LG Chem Research Park, Daejeon 305-380, Republic of Korea.
Biotechnol Adv. 2013 Mar-Apr;31(2):246-56. doi: 10.1016/j.biotechadv.2012.11.002. Epub 2012 Nov 12.
The continuous release of toxic persistent organic pollutants (POPs) into the environment has raised a need for effective cleanup methods. The tremendous natural diversity of microbial catabolic mechanisms suggests that catabolic routes may be applied to the remediation of POP-contaminated fields. A large number of the recalcitrant xenobiotics have been shown to be removable via the natural catabolic mechanisms of microbes, and detailed biochemical studies of the catabolic methods, together with the development of sophisticated genetic engineering, have led to the use of synthetic microbes for the bioremediation of POPs. However, the steric effects of substituted halogen moieties, microbe toxicity, and the low bioavailability of POPs still deteriorate the efficiency of removal strategies based on natural and synthetic catabolic mechanisms. Recently, abiotic redox processes that induce rapid reductive dehalogenation, hydroxyl radical-based oxidation, or electron shuttling have been reasonably coupled with microbial catabolic actions, thereby compensating for the drawbacks of biotic processes in POP removal. In this review, we first compare the pros and cons of individual methodologies (i.e., the natural and synthetic catabolism of microbes and the abiotic processes involving zero-valent irons, advanced oxidation processes, and small organic stimulants) for POP removal. We then highlight recent trends in coupling the biotic-abiotic methodologies and discuss how the processes are both feasible and superior to individual methodologies for POP cleanup. Cost-effective and environmentally sustainable abiotic redox actions could enhance the microbial bioremediation potential for POPs.
有毒的持久性有机污染物（POPs）持续不断地释放到环境中，这就需要开发有效的清理方法。微生物代谢机制具有巨大的自然多样性，这表明代谢途径可应用于 POP 污染场地的修复。大量的难降解污染物已被证明可以通过微生物的自然代谢机制去除，对代谢方法的详细生化研究，以及复杂的遗传工程技术的发展，已经导致了使用合成微生物进行 POP 的生物修复。然而，取代卤原子部分的空间效应、微生物毒性以及 POP 的低生物利用度仍然会降低基于自然和合成代谢机制的去除策略的效率。最近，诱导快速还原脱卤、基于羟基自由基的氧化或电子穿梭的非生物氧化还原过程已与微生物代谢作用合理结合，从而弥补了生物过程在 POP 去除中的缺点。在这篇综述中，我们首先比较了单独方法的优缺点（即微生物的自然和合成代谢以及涉及零价铁、高级氧化过程和小分子刺激物的非生物过程）在 POP 去除方面的应用。然后，我们重点介绍了生物-非生物方法相结合的最新趋势，并讨论了这些方法在 POP 清理方面的可行性和优越性。经济有效的环境可持续的非生物氧化还原作用可以增强微生物对 POP 的生物修复潜力。
