纳米颗粒对耐冷脱氮菌及其脱氮过程的毒害调控研究进展

Toxicity of nanoparticles to cold-adapted denitrifying bacteria and the denitrification process and the countermeasures

摘要:

生物脱氮具有经济高效、绿色环保的特点，在废水处理中具有广阔前景；目前在废水处理工艺中脱氮效果较好的微生物大部分为嗜温菌，这类菌在低温条件下的脱氮效率会受到强烈抑制，而耐冷脱氮菌可有效抵抗低温环境并进行高效脱氮，逐渐引起了研究者们的重视。其次，纳米颗粒（nanoparticles，NPs）在生物学、农学、医药等领域的应用日渐广泛，但在生产、储存和使用含NPs产品的过程中，不可避免地会向水和土壤环境释放NPs，在水环境中，NPs的大量积累会阻碍微生物的脱氮过程，也对废水处理提出了新的挑战，成为公众日益关注的环境问题和研究热点。当前，有部分研究已关注于耐冷菌的脱氮过程、NPs对耐冷菌脱氮过程的毒害作用及减毒措施。基于此，本篇文章将阐述耐冷菌的耐冷机理与脱氮过程，阐明NPs对耐冷菌脱氮过程的毒害作用与减毒调控措施，为低温环境下采用微生物处理含有NPs的氮污染废水提供理论依据。

关键词:生物脱氮;耐冷脱氮菌;纳米颗粒;毒害作用;减毒调控

Abstract:

Biological denitrification is cost-effective, efficient, and environmentally friendly, which thus has broad prospects in the wastewater treatment. At the moment, most of the available denitrifying microorganisms in wastewater treatment are mesophilic bacteria. However, the denitrification is significantly inhibited in the case of low temperature. The cold-adapted denitrifying bacteria, with tolerance to low temperature and high efficiency in denitrification, have attracted the interest of scholars. Moreover, the nanoparticles (NPs) are widely used in biology, agronomy, medicine and other fields, which, however, are inevitably released to water and soil in the production, storage, and usage of NPs-containing products. Massive accumulation of NPs in the water will hinder the denitrification of microorganisms, posing a challenge to wastewater treatment and arousing the concern of scholars. The denitrification process of cold-adapted bacteria, the toxicity of NPs to the denitrification, and the countermeasures have been studied. On this basis, this article describes the cold-adapt mechanism and denitrification process of the cold-adapted bacteria and discusses the toxicity of NPs to the denitrification process and the countermeasures, which is expected to lay a theoretical basis for the use of microorganisms to treat nitrogen-polluted wastewater containing NPs in a low temperature environment.

Key words:biological denitrification;cold-adapted denitrifying bacteria;nanoparticles;toxicity;regulation for toxicity reduction