Chemical precipitation to form magnesium ammonium phosphate (MAP) is an effective technology for recovering ammonium nitrogen (NH4(+)-N). In the present research, we investigated the thermodynamic modeling of the PHREEQC program for NH4(+)-N recovery to evaluate the effect of reaction factors on MAP precipitation. The case study of NH4(+)-N recovery from coking wastewater was conducted to provi...

L-Glutamine, when purified free of traces of NH4+ present in solution, does not act as an alternative substrate to NH4+ for the NADP-specific glutamate dehydrogenase of Neurospora. L-Glutamine interferes with detection of small quantities of NH4+ by Nessler's reagent. L-Asparagine is not an alternative substrate to NH4+ for this enzyme.

Ammonium (NH4) toxicity is an issue of global ecological and economic importance. In this review, we discuss the major themes of NH4 toxicity, including the occurrence of NH4 in the biosphere, response differences to NH4 nutrition among wild and domesticated species, symptoms and proposed mechanisms underlying toxicity, and means by which it can be alleviated. Where possible, nitrate (NO3) nutr...

NH4 (+) nutrition provokes mild toxicity by enhancing H2O2 accumulation, which acts as a signal activating systemic acquired acclimation (SAA). Until now, induced resistance mechanisms in response to an abiotic stimulus and related to SAA were only reported for exposure to a subsequent abiotic stress. Herein, the first evidence is provided that this acclimation to an abiotic stimulus induces re...

The maintenance of low availability of mineral N in heath soils is thought to be a key factor for the stability of heathland ecosystems. We investigated the turnover of NH4 ‡ and NO3 ÿ in the organic surface layer of soils from a Danish heathland using N isotope techniques in laboratory incubations. The soils were sampled under intact and dead Calluna vegetation. The dead Calluna vegetation had...

Ammonium (NH4+) is both a necessary nutrient and an important signal in plants, but can be toxic in excess. Ammonium sensing and regulatory mechanisms in plant cells have not been fully elucidated. To decipher the complex network of NH4+ signaling, we analyzed [Ca2+]cyt-associated protein kinase (CAP) genes, which encode signaling components that undergo marked changes in transcription levels i...

In vitro immune effects of Pt compounds of occupational and/or environmental importance, or those used in cancer treatment were studied. Spontaneous and PHA-stimulated proliferation of peripheral blood mononuclear cells (PBMC) and in vitro release of TNF-alpha, IFN-gamma, and IL-5 were assessed in presence of high and very low concentrations of Pt salts: 10(-4) and 10(-7) M (NH4)2[PtCl6], (NH4)...

Since increasing the NO3 and NH4 make eutrophication in waterbodies, microalgae tolerance tohigh concentrations of NO3 and NH4 and their growth in these levels indicate the bioremediationpotential of nitrogen-rich wastewaters and produce efficient algal biomass in freshwaterenvironments. To evaluate the tolerance of green algae, Scenedesmus quadricauda to different NO3and NH...

UNLABELLED The renal medullary thick ascending limb (MTAL) actively reabsorbs ammonium ions. To examine the effects of NH4+ transport on intracellular pH (pHi) and the mechanisms of apical membrane NH4+ transport, MTALs from rats were isolated and perfused in vitro with 25 mM HCO3(-)-buffered solutions (pH 7.4). pHi was monitored using the fluorescent dye BCECF. In the absence of NH4+, the mean...