Many fungi in the centre of the group of Fusarium and its teleomorphs were shown to be capable of reducing nitrite anaerobically to form nitric oxide (NO), nitrous oxide (N2O), and/or dinitrogen (N2). Several strains could reduce nitrate as well. Nitrous oxide was the major product of the reduction of nitrate or nitrite. Several fungi could also form N2. When [15]nitrite was used as substrate f...

The effective management of high ammonium containing wastewater is important for the sustainable development of the wastewater industry. A pre-denitrification and post-nitrification two-sludge system was proposed to treat high ammonium containing wastewater with low carbon-to-nitrogen (C/N) ratios. In the system, pre-denitrification was adopted to use organic carbon in raw wastewater efficientl...

This paper presents findings of an investigation into the relationships between nitrate utilization rate (NUR), pH and oxidation reduction potential (ORP) during anoxic transformation processes in municipal wastewater. The study utilized municipal wastewater obtained from a wastewater treatment plant located within Shah Alam, Malaysia. Denitrification was observed by monitoring the change in ni...

18 Denitrification was measured in three structurally different coastal microbial mats by 19 using the stable isotope technique. The composition of the denitrifying community was 20 determined by analyzing the nitrite reductase (nirS and nirK) genes using clone libraries 21 and the GeoChip. The highest potential rate of denitrification (7.0±1.0 mmol N m d) 22 was observed during summer at stati...

Net nitrous oxide production and denitrification activity were measured in two mangrove ecosystems of Goa, India. The relatively pristine site Tuvem was compared to Divar, which is prone to high nutrient input. Stratified sampling at 2-cm intervals within the 0- to 10-cm depth range showed that N2O production at both the locations decreased with depth. Elevated denitrification activity at Divar...

Gaseous losses of nitrogen (N2 oIr N20) fr'Om bacterial culture media and soils maintained under conditions commonly considered aerobic have been observed frequently (Meiklejohn, 1940; Corbet and Wooldridge, 1940; Korsakova, 1941; Broadbent, 1951; Broadbent and Stojanovie, 1952; Marshall et al., 1953; and Collins, 1955). Not all workers, however, have considered such observations as proof that ...

The denitrifying fungus Cylindrocarpon tonkinense was thought to be able to denitrify only nitrite (NO2-) but not nitrate (NO3-) to form nitrous oxide (N2O). Here we found, however, that C. tonkinense can denitrify NO3- under certain conditions. Presence of ammonium (NH3+) in addition to NO3- and the use of a fermentable sugar as an electron donor were key conditions for inducing the denitrifyi...

The reduction of sulfate to sulfide was seldom considered for high-salt wastewater treatment, although could supply electron donors remove nitrite. reduction, heterotrophic denitrification and autotrophic were integrated in one biofilm-enhanced treatment system the used as an intermediate reaction. Both reactor performances spatial distribution bacterial communities studied. metabolic pathways ...

Nitrous oxide can be a harmful by-product in nitrogen removal from wastewater. Since wastewater treatment systems operate under different aeration regimens, the influence of different oxygen concentrations and oxygen fluctuations on denitrification was studied. Continuous cultures of Alcaligenes faecalis TUD produced N2O under anaerobic as well as aerobic conditions. Below a dissolved oxygen co...

The performance of acetic acid-supported pH-heterogenized heterotrophic denitrification (HD) facilitated with ferrous sulfide-based autotrophic denitrification (AD) was investigated in upflow activated carbon-packed column reactors for reliable removal of highly elevated nitrate (42 mg NO(3)-Nl(-1)) in drinking water. The use of acetic acid as substrate provided sufficient internal carbon dioxi...