ABSTRACT A sequencing batch biofilm reactor under intermittent micro-aerobic or anaerobic conditions was investigated to remove pyridine at various concentrations from synthetic wastewater. The results showed that over 98% of pyridine (influent concentration ≤200 mg L−1) was degraded under intermittent micro-aerobic condition, while about 21% of pyridine was removed under anaerobic condition. Additionally, at least 60% of nitrogen located in the pyridine ring was transformed to ammonium. At the same time, the sulphate reduction was obviously inhibited under intermittent micro-aerobic conditions. The microscopic observation showed that abundant microorganisms were attached on the surface or inside of porous biocarriers under intermittent micro-aerobic conditions after a short-term period of operation. High-throughput sequencing analysis demonstrated that Azotobacter, Rhodobacteraceae and Tolumonas were the dominant species in the intermittent micro-aerobic system. The kinetic study at steady period showed that pyridine degradation was fitted well with the pseudo-first-order model (R2 > 0.96). The two possible intermediate products were identified and the possible biodegradation pathway of pyridine was proposed under micro-aerobic condition. GRAPHICAL ABSTRACT

中文翻译：

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间歇微好氧条件下序批式生物膜反应器强化吡啶生物降解

摘要研究了在间歇性微好氧或厌氧条件下的序批式生物膜反应器，以从合成废水中去除各种浓度的吡啶。结果表明，在间歇微好氧条件下，超过98%的吡啶（进水浓度≤200 mg L-1）被降解，而在厌氧条件下，大约21%的吡啶被去除。此外，位于吡啶环中的至少 60% 的氮转化为铵。同时，在间歇性微好氧条件下，硫酸盐还原受到明显抑制。显微观察表明，在间歇性微需氧条件下，经过短期操作后，多孔生物载体的表面或内部附着了大量微生物。高通量测序分析表明，固氮菌、红杆菌科和 Tolumonas 是间歇微需氧系统中的优势种。稳态动力学研究表明，吡啶降解符合拟一级模型（R2>0.96）。鉴定了两种可能的中间产物，并提出了微需氧条件下吡啶可能的生物降解途径。图形概要 鉴定了两种可能的中间产物，并提出了微需氧条件下吡啶可能的生物降解途径。图形概要 鉴定了两种可能的中间产物，并提出了微需氧条件下吡啶可能的生物降解途径。图形概要