全程与短程缺氧反硝化降解苯酚的动力学及菌群结构对比

Comparison of Dynamic Characteristic and Bacterial Community Structure on Phenol Degradating Between Complete and Short-cut Denitrification System

在同一实验平台上建立起两个平行的全程与短程反硝化实验装置,均以苯酚为单一碳源进行缺氧反硝化降解。结果显示,两个反硝化体系的苯酚和硝态氮(亚硝态氮)去除率均在83%,99%左右,全程和短程反硝化体系的比反硝化速率(以N元素计)分别为4.98,6.45mg/(g·h).通过PCR-DGGE及切胶测序对两个反硝化体系的菌群结构进行了分析,发现全程反硝化菌群的丰富度值和多样性指数要高于短程;全程与短程反硝化降解苯酚的细菌菌纲均以几类变形菌纲(Alphaproteobacteria,Betaproteobacteria,Gammaproteobacteria)和拟杆菌纲(Bacteroidetes)为主。DGGE图谱主成分分析表明,全程与短程反硝化菌群之间具有一定联系性,菌群培养具有相互转化的可能性;短程反硝化体系的隶属于Simplicispirasp.的特有菌种与全程反硝化体系的隶属于Thermomonas sp.的特有菌种在系统发育上存在较亲近的遗传关系。

Two parallel devices of complete and short-cut denitrification were established under the same experimental conditions.Phenol was used as carbon source in the experiment.In two devices,the removal rates of phenol were both about 83%,and the removal rate of nitrate or nitrite nitrogen was 99%.The specific denitrification rate(RDN)was 4.98 and 6.45 mg N/(g VSS·h)respectively in the complete and short-cut denitrification system.Through PCR-DGGE and rubber cutting sequencing,the bacterial community structures of two denitrification systems were analyzed.In the complete denitrification system,the richness value(Rs)and diversity index(H)of bacterial flora were higher;In the two denitrification systems,the classes of bacteria were mainly Proteobacteria(α-,β-,δ-)and Bacteroidetes;According to the result of principal component analysis(PCA),bacteria communities of two systems had a certain relationship and could be cultivated and transformed mutually;From the analysis of phylogenetic tree,a close genetic relationship was found between specific strains related to Simplicispira sp.(short-cut denitrification)and Thermomonas sp.(complete denitrification).