好氧反硝化微生物学机理与应用研究进展

近年来,关于好氧反硝化过程的研究主要集中在三个方面:分别是好氧反硝化菌株的分离和脱氮性能表征,好氧反硝化微生物的应用潜力分析,以及好氧反硝化过程的机理研究。好氧反硝化菌株分布范围广泛,可从多种环境中分离得到,种属以Pseudomonas sp.、Alcaligenes sp.和Paracoccus sp.为主。好氧反硝化菌株及菌群在实验室条件下表现出优良的耐冷、耐盐特性,并具有可降解毒性有机物及N_2O减排的潜力。关于好氧反硝化过程的机理研究表明,虽然硝酸盐作为电子受体的竞争力比氧气弱,但反硝化作为辅助电子传递途径,可提高产能效率,防止NAD(P)H的过量积累。因此,硝酸盐可与氧气同时参与微生物的新陈代谢,即发生好氧反硝化现象。未来除了继续分离更新更好的好氧反硝化菌株外,应加强对好氧反硝化机理及实际生物强化方面的研究。

Microbiology and potential application of aerobic denitrification: a review

In recent years, aerobic denitrification researches focused on three fields: isolation and performance of aerobic denitrification strains, potential applications of aerobic denitrification microorganisms, and aerobic denitrifying mechanism. Aerobic denitrification strains are widely distributed in several environments. Functional species were mostly selected from Pseudomonas sp., Alcaligenes sp. and Paracoccus sp. In lab-scale tests, some aerobic denitrification microorganisms showed excellent psychrotolerant or haloduric property, and other strains had great potential on biodegradation of toxicant, or N2O emission reduction. Mechanism result of aerobic denitrification indicated that the competitiveness of nitrate was weaker than oxygen as an electron acceptor, whereas denitrification process could still occur as an assistant electron transport pathway to prevent the overload of NAD(P)H. Therefore, nitrate and oxygen could simultaneously participate in metabolism of microorganisms. However, researches on mechanisms and practical bioaugmentation of aerobic denitrification microorganisms are still insufficient, and more researches and process tests should be carried out in the future.