A fiber-based biofilm reactor was developed using a laboratory-scale apparatus for treatment of nitrate-contaminated groundwater. Denitrification bacteria were inoculated by anaerobic sludge from a wastewater treatment plant. Nitrate removal efficiency, nitrite accumulation, COD and pH in the treated water were investigated under various conditions set by several parameters including hydraulic ...

Stoicheometries and rates of proton translocation associated with respiratory reduction of NO3- have been measured for spheroplasts of Escherichia coli grown anaerobically in the presence of NO3-. Observed stoicheiometries [leads to H+/NO3- ratio; P. Mitchell (1966) Chemiosmotic Coupling in Oxidative and Photosynthetic Phosphorylation, Glynn Research, Bodmin] were approx. 4 for L-malate oxidati...

Insulin resistance and obesity are characterized by low nitric oxide (NO) bioavailability. Insulin sensitivity is improved with stimulation of NO generating pathways. Consumption of dietary nitrate (NO3-) increases NO formation, via NO3- reduction to nitrite (NO2-) by oral bacteria. We hypothesized that acute dietary nitrate (beet juice) ingestion improves insulin sensitivity in obese but not i...

In the context of agricultural nitrogen excesses in northwestern France, pyrite-bearing weathered schist aquifers represent important hydrological compartments due to their capacity to eliminate nitrate (NO3-). Under oxygen-free conditions, nitrate is reduced simultaneously with the oxidation of pyrite leading to the release of sulfate (SO4/2-). The aim of the present study is to identify the h...

290 T demand for higher crop yields and the relatively low cost of N fertilizer per unit of yield increase has resulted in increased NO3–N concentrations in the groundwater, especially in areas with coarse-textured soils and shallow groundwater. An increased level of NO3–N in the groundwater is not a locally confi ned problem, however, as NO3–N from agricultural sources in the Midwest has been ...

[1] We present estimates of nitrogen (N) inputs to the Changjiang River basin for the period 1968–1997. The total N input is approximately 7.8 10 kg in 1997, which is a threefold increase over 1968 levels. N fixation was often a dominant input before 1978, providing about 2.2 10 kg year , while N fertilizer dominated N input after 1983, supplying an additional input of some 4.4 10 kg year . Mor...

We have identified certain heat-resistant (HR) and heat-sensitive (HS) lettuce (Lactuca sativa) recombinant inbred lines (RILs) from 113 lines under hot ambient temperature by studying the root morphology, shoot and root productivity. Except for temperature, one of the other major determinants of root morphology is nitrate (NO3 ) availability. In this study, total productivity, root morphology,...

Background Vegetables play an important role in human nutrition. Nitrate content is a signifi-cant quality criterion to determine characteristic of vegetables. About 80% of nitrate intake in human is from vegetables and fruits. High dietary intake of nitrate is seen as an undesirable be-cause of its association with gastric cancer and infantile methemoglobinemia. Varzeghan, North¬western Iran i...

knowledge of crop N need may be used by producers to guide future fertilizer-N management thereby improving The end-of-season stalk nitrate test provides a method of assessing profitability and reducing environmental degradation. the N available to the corn (Zea mays L.) crop during the latter part of the season. This study was conducted to determine how stalk nitrate To be a useful crop manage...