Denitrification characteristics and pathways of a facultative anaerobic denitrifying strain, Pseudomonas denitrificans G1

A New Acinetobacter Isolate Is an Extremely Efficient Biofilm-Formative Denitrifying Bacterium

“…Although the nitrate removal was high, 50% was consumed by the culture to build biomass and was not used as an electron acceptor in the denitrification process. This ratio is higher than in the experiments conducted by Chen et al (2020) on aquaculture effluents purification bioaugmented with a Pseudomonas denitrificans G1 culture. However, previous studies by Zhang et al (2018) and Zhao et al (2018), which focused on pure denitrifying cultures (Paracoccus versutus KS293 Pseudomonas stutzeri strain XL-2) and measured the intracellular nitrogen of the culture, showed a markedly lower assimilation ratio of nitrogen into the cells (only 12-15% of the nitrate was assimilated by the cells).…”

“…Their study proved that a C:N ratio greater than 6:1 is not effective and hinders the bacterial denitrification activity. Conversely, Chen et al (2020) studied Pseudomonas denitrificans G1, a facultative anaerobic denitrifying strain. They concluded that at a C:N ratio of 3:1 the denitrification was poor and the strain needed a ratio of at least 5:1 with best performance at a ratio of 8:1.…”

“…Therefore, wastewater treatment and aquaculture facilities are investing great efforts to develop highly efficient denitrification processes, and various technologies have been developed to improve the efficiency of nitrate removal (Bernhard, 2010;Paul, 2014;Zhang et al, 2015;Pan et al, 2017). While chemical and physical removal methods such as ion exchange, reverse osmosis, and electrodialysis have been found to be cost-ineffective due to high costs (installation and maintenance), biological removal of nitrogen compounds from water has been found to be both effective and much more economical (Garbisu et al, 1991;Sharma and Sobti, 2012;Chen et al, 2020).…”

Groundwater Nitrate Removal Performance of Selected Pseudomonas Strains Carrying nosZ Gene in Aerobic Granular Sequential Batch Reactors

“…The mineral salts per liter of distilled water comprised 0.1 g MgSO 4 •7H 2 O, 0.085 g K 2 HPO 4 , 0.04 g KCl, and 0.03 g KH 2 PO 4 . Different C:N (carbon/nitrogen) ratios were tested (Table 1) using acetate or methanol, with the aim of establishing the relationship most suitable for the granulation process and the nitrate removal capacity [29]. The sequential batch reactors cycle had a hydraulic retention time of 10 h, and the exchange volume was 60% of the operational volume reactor in each cycle.…”

“…Although P. denitrificans Z1 was initially included in this study, the inability of this strain to form granules precluded its use as an inoculum in GSBR systems. Other strains of P. denitrificans could be tested in order to establish whether it is possible to use this denitrifying microorganism [29]. Our observations must be considered limited to the strains used in our study, although, based on nitrogen mass balance results, it appears that nitrate removal and the transformation of nitrate to dinitrogen gas could be easily modified by adjusting the concentration of the carbon source in the influent.…”