多环芳烃是一类具有致癌、致畸、致突变性质的持久性有机污染物，主要来源于煤、石油等燃料的不完全燃烧，易吸附于固体颗粒表面和有机腐殖质，化学结构稳定，能长期存在于自然环境，给人类健康和生态环境带来很大的危害。中国土壤多环芳烃污染严重，因此急需寻求有效的修复方法进行治理。在众多的多环芳烃污染修复方法中，微生物修复因其低成本、高效、污染少等优点成为研究热点。科学家们从自然界中分离出了多种细菌、真菌等具有降解多环芳烃能力的微生物，并对多环芳烃的降解机理进行了探索，结果表明，微生物在代谢活动过程中能够产生酶来实现对土壤中多环芳烃的降解。细菌主要通过产生双加氧酶来催化多环芳烃的加氧反应，而真菌可以通过分泌木质素降解酶系或单加氧酶来氧化多环芳烃。两种途径均是首先通过降低多环芳烃的稳定性，使之容易被进一步降解。目前，微生物修复技术正逐步应用于PAHs污染土壤的实地修复，且已取得一定成效。文章简要介绍了降解多环芳烃的微生物，对多环芳烃的微生物降解机制进行了综述，讨论了影响微生物修复过程的因素，列举了常见的微生物修复相关技术，展望了今后的研究趋势。%Polycyclic aromatic hydrocarbons (PAHs), which mainly resulted from incomplete combustion of coal, petroleum and other fuels, are a kind of carcinogenic, teratogenic and mutagenic persistent organic pollutants (POPs). Each of them has stable chemical structure and easily adsorb on solid surface and organic humus. For this case, PAHs can exist in the natural environment for a long time and has great potential harm to human health and ecological environment. In China, the PAHs pollution in soil is a very serious problem, so it is urgent to explore an effective technology for removal of PAHs. Recently, microbial remediation was focused on for its advantages of low cost, high efficiency and less pollution with PAHs-degrading bacteria and fungi. The enzymes are im-portant in degradation of soil PAHs during microbial remediation. PAHs can be degraded through the oxidation of benzene ring by dioxygenase enzymes of bacteria. PAHs can also be oxidized by lignin degrading enzymes or monooxygenases of fungi. The stabili-ties of intermediates are usually lower than those of parent PAHs and can be easily further degraded. Thus, the microbial remediation has been utilized in the treatment practice of soil PAHs. In this work, the PAHs-degrading microbe and mechanism were reviewed. The influences of different factors on the microbial remediation of soil PAHs were discussed. Three microbial remediation techniques of PAHs-contaminated soil were introduced. Moreover, some suggestions were provided for the development of the microbial reme-diation technology to remove PAHs in soil.
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