The Volcani Center, Institute of Agriculture Engineering, Bet Dagan 50250, Israel.
Bioresour Technol. 2012 Nov;124:413-20. doi: 10.1016/j.biortech.2012.08.049. Epub 2012 Aug 19.
In this study granular sludge taken from a denitrifying upflow sludge reactor was characterized. Denitrification rates were determined in batch tests with and without external carbon source addition and pH microprofiles of the granules were studied. The microbial community structure was also determined. The results showed that denitrification without carbon source addition occurs; however, the process rate was lower than with external carbon source. This suggests that bacteria use dead biomass and extracellular material in the granular sludge as a carbon source when readily available substrate has been exhausted and nitrate is still present. Microprofiles showed a slight pH decrease for denitrification without external carbon source addition, and an increase in pH when using nitrite as the electron acceptor. Microprofiles using acetate as the carbon source for denitrification showed a significant increase in pH. Clone sequences obtained were close to the species Vitellibacter sp., Denitromonas indolicum str. and Denitromonas aromaticaus sp.
本研究对取自反硝化上流污泥反应器的颗粒污泥进行了特性分析。通过添加和不添加外源碳源的批式试验测定了反硝化速率，并研究了颗粒的 pH 微区。还确定了微生物群落结构。结果表明，即使不添加外源碳源也能发生反硝化，但过程速率低于添加外源碳源时。这表明，当可用底物耗尽且仍存在硝酸盐时，细菌会将颗粒污泥中的死生物质和细胞外物质用作碳源。不添加外源碳源的反硝化过程中，微区的 pH 略有下降，而使用亚硝酸盐作为电子受体时，pH 则升高。当使用乙酸盐作为反硝化的碳源时，pH 显著升高。获得的克隆序列与物种 Vitellibacter sp.、Denitromonas indolicum str. 和 Denitromonas aromaticaus sp. 密切相关。
