好氧反硝化微生物多样性及其反硝化功能初步研究

Diversity of Aerobic Denitrifying Microbes from Various Environment and Analysis of Their Denitrification Ability

为研究污水厂/养殖池中好氧反硝化微生物的多样性及菌株反硝化能力,本研究采集了位于福建省厦门市和漳州市的污水处理厂、排污口、污水池、对虾养殖池的污水和污泥样品进行好氧反硝化微生物的富集、分离、鉴定和功能筛选。分别以NaNO3、NaNO2作为唯一氮源共分离纯化获得128株单菌。其中以NaNO3为唯一氮源分离得到63株,以NaNO2为唯一氮源分离得到65株。16SrRNA基因序列分析表明,128株单菌分属于γ-变形菌纲(Gammaproteobacteria,58.6%)、芽胞杆菌纲(Bacilli,6.4%)、放线菌纲(Actinobacteria,11.7%)、α-变形菌纲(Alphaproteobacteria,8.6%)、纤维菌纲(Cytophagia,2.3%)、鞘脂杆菌纲(Sphingobacteria,0.8%)和黄杆菌纲(Flavobacteria,1.6%)7个纲中的38个属。其中盐单胞菌属(Halomonas,29.7%)和芽胞杆菌属(Bacillus,12.5%)为优势菌属,并且广泛存在于各个样品中。反硝化功能初筛结果表明,35株菌能在72h内将20mg·L-1 NO-3-N/NO-2-N完全去除;复筛结果表明,21株菌能在72h内将100 mg·L-1 NO-3-N/NO-2-N完全去除,并且盐单胞菌属、卓贝尔氏菌属(Zobellella)、斯塔普氏菌属(Stappia)及节杆菌属(Arthrobactor)反硝化效果较好,其中斯塔普氏属是首次报道具有好氧反硝化功能。本研究结果表明,污水场/养殖池等环境中可培养反硝化细菌多样性丰富,同时高效反硝化菌的获得也为含氮废水的生物处理提供了良好的菌种资源。

In order to study the diversity of aerobic denitrification strain,sediment,seawater and sludge samples were collected from shrimp culture farm,waste water treatment plant,and sewage drainage in Xiamen and Zhangzhou,Fujian province.A total of 128 bacterial strains were enriched and isolated using nitrite（65strains）and nitrate（63strains）as the sole nitrogen source.Phylogenetic analysis based on 16 SrRNA gene sequences indicated that 128 bacterial strains belonged to Gammaproteobacteria（58.6%）,Bacilli（16.4%）,Actinobacteria（11.7%）,Alphaproteobacteria（8.6%）,Cytophagia（2.3%）,Sphingobacteria（0.8%）and Flavobacteria（1.6%）,which consisted of 38 genera,with the dominant genera of Halomonas（29.7%）and Bacillus（12.5%）.Halomonas spp.and Bacillus spp.dominated the various samples.Denitrification ability analysis indicated that 35 strains could remove 20mg·L^-1 NO-3-N/NO-2-N completely within 72 hand 21strains could remove 100mg·L^-1 NO-3-N/NO-2-N completely within 72 h,among which Halomonas spp.,Zobellellaspp.,Stappiaspp.and Arthrobacterspp.showed the highest nitrogen removal efficiency.Besides,Stappiaspp.were first reported as aerobic denitrifier.The results of this study showed thediversity of aerobic denitrification strains in sewage/sludge from various environments,as well as provided huge number of denitrifying bacteria to be potentially applied in biological treatment of nitrogenous wastewater.