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To better understand the mechanism of salt tolerance, we analyzed cotton growth and the ionomes in different tissues under different types of salt–alkali stress. Cotton was exposed to the soil salt and alkali stresses, NaCl, Na2SO4, and Na2CO3 + NaHCO3, in a pot study. Salt and alkali stress significantly inhibited cotton growth, significantly reduced root length, surface area, and volume, and significantly increased relative electrical conductivity (REC) and malondialdehyde (MDA) content but also significantly increased antioxidant enzyme activities, and proline (Pro) content. The REC in leaves was higher under salt stress than under alkali stress, but the effects on Pro were in the order Na2CO3 + NaHCO3 > NaCl > Na2SO4. Principal component analysis showed a significant difference in ion composition under the different types of salt–alkali stress. Under the three types of salt–alkali stress, concentrations of Na and Mo increased significantly in different organs of cotton plants. Under NaCl stress, the absorption of Ca was inhibited, the transport capacity of P, Mg, and Cu was reduced, and the ion balance was maintained by promoting the uptake and transport of Zn, Mn, Al, and Mo. Under Na2SO4 stress, the absorption of P and Ca was inhibited, the transport capacity of Mg, B, and Cu was reduced, and the ion balance was maintained by promoting the uptake and transport of S, Zn, Fe, Mo, Al, and Co. Under Na2CO3 + NaHCO3 stress, the absorption of P and S was inhibited, the transport capacity of Mg and B was reduced, but that of Al and Fe increased, and the ion balance was maintained by promoting the uptake and transport of Mn, Mo, Ni, and Co. The relative expression of GhSOS1 and GhNHX1 in leaves increased significantly under salt stress but decreased under alkali stress. These results suggest that cotton is well-adapted to salt–alkali stress via the antioxidant enzyme system, adjustment of osmotic substances, and reconstruction of ionic equilibrium; neutral salt stress primarily disrupts the ion balance, whereas alkali stress decreases the ability to regulate Na and inhibits the absorption of mineral elements, as well as disrupts the ion balance; and the changes in the expression of salt tolerance-related genes may partially explain the accumulation of Na ions in cotton under salt–alkali stress. [ABSTRACT FROM AUTHOR]

The plant stress hypothesis posits that a herbivore’s reproductive success increases when it feeds on stressed plants, while the plant vigor hypothesis predicts that a herbivore preferentially feeds on more vigorous plants. We examined these opposing hypotheses by growing spider mites (Tetranychus urticae) on the leaves of stressed and healthy (vigorous) cucumber plants. Host plants were grown under controlled conditions at low, moderate, and high concentrations of NaCl (to induce salinity stress), at low, moderate, and high fertilizer concentrations (to support growth), and without these additions (control). The effects of these treatments were evaluated by measuring fresh and dry plant biomass, carotenoid and chlorophyll content, antioxidant enzyme activity, and concentrations of PO43−, K+, and Na+ in plant tissues. The addition of low concentrations of fertilizer increased dry mass, protein, and carotenoid content relative to controls, suggesting a beneficial effect on plants. The highest NaCl treatment (2560 mg L−1) resulted in increased Na+ and protein content relative to control plants, as well as reduced PO43−, K+, and chlorophyll levels and reduced catalase and ascorbate peroxidase enzyme activity levels. Analysis of life table data of T. urticae mites raised on leaves from the aforementioned plant groups showed the intrinsic rate of increase (r) for mites was 0.167 day−1 in control specimens, 0.125 day−1 for mites reared on plants treated with a moderate concentration of fertilizer (10 mL L−1), and was highest (0.241 day−1) on plants grown under moderate salinity conditions (1920 mg L−1 NaCl). Reproductive success of T. urticae did not differ on plants watered with a moderate concentration of NaCl or a high concentration of fertilizer. The moderately-stressed plants formed a favorable environment for the development and reproduction of spider mites, supporting the plant stress hypothesis. [ABSTRACT FROM AUTHOR]

The aim of our study is to evaluate the impact of Bousfer desalination plant brine discharges on the Algerian west coast, on a natural population of the marine gastropod mollusc Patella rustica. The effects of a chronic exposure to such discharges are complex to understand due to the combined effects of environmental physico-chemical parameters (e.g., high salinity) and different pollutants that can modulate the physiological responses of this species to stress. In this context, we assessed the biological effects in a marine species P. rustica, by a multibiomarker approach that provided information on the health status of organisms in response to such an environmental stress. We measured biomarkers in the whole soft tissues of limpets as indicators of neurotoxicity (AChE activity), oxidative stress (CAT, SOD, GR, and GPx activities), biotransformation (GST), oxidative damage (LPO through TBARS levels), and genotoxicity (CSP 3-like activity). In parallel, hydrological parameters were measured in the Bay of Oran, at four selected sites: site H considered as a 'hotspot,' located at Bousfer desalination plant; two other sites E and W, at the east and the west of H respectively; finally, site R 'reference' located in Madragh, which is considered as a remote clean site. Our analyses revealed that the activities of antioxidant defense enzymes reached the highest levels in P. rustica collected from site H. The activation of antioxidant defense system in these organisms translated the alteration of their status health, reflecting a level of environmental disruption generated by the desalination plant brine discharges and the high salinity in this area. We also observed that the tissues of limpets collected from site H as well as the two other sites, E and W, had undergone molecular damage, confirmed by the high levels of CSP 3-like activity. This damage resulted from chronic exposure to environmental conditions, potentially genotoxic, due to the desalination plant discharges. The present results indicate the adverse impact of brine effluents from desalination plants on marine fauna and suggest the need for a more consistent approach to environmental management of brine discharges. [ABSTRACT FROM AUTHOR]

Four new isostructural salts, [M(phen)](IBr)·3CHCl where, M=Co ( 1), Ni ( 2), Cu ( 3), or Zn ( 4) have been synthesized by reacting the metal nitrates with 1,10-phenanthroline (phen) in presence of potassium bromide and iodine in a two phase procedure. The [Cu(phen)] coordination corresponds to tetragonally elongated octahedron while the other three are much more symmetrical. The pure Cu complex as well as other salts doped with Cu give hyperfine resolved EPR spectra in a wide temperature range showing dynamic Jahn-Teller distortion. The trihalide ion is nearly linear with bond distances in the range, I-I (2.786-2.833 Å) and I-Br (2.759-2.794 Å). Geometry optimization (DFT and MP2 methods) predicts a much more unsymmetrical 'gas phase' structure for IBr ion. Calculated Raman frequencies are in reasonable agreement with observed values. Electronic spectral results show that the integrity of the trihalide ion is retained in solution. Graphical Abstract: Three new isostructural compounds having the general formula [M(phen)](IBr) having nearly symmetrical IBr ion are synthesized and characterized. [ABSTRACT FROM AUTHOR]

Dietary sodium content is considered as a major contributor to hypertension and cardiovascular diseases. Mozzarella cheese contains high amount of sodium, and addition of emulsifying salts (ESs) to the manufacture of processed cheese further adds to the overall sodium content. The present investigation envisaged the manufacture of low-sodium processed Mozzarella cheese by partial replacement of sodium chloride with potassium chloride (KCl) and also by using potassium-based emulsifying salts, i.e., potassium citrate and di-potassium phosphate, in place of sodium-containing salts. Desired level of potassium chloride and potassium-based emulsifying salt was optimized using response surface methodology (RSM). Sensory attributes, instrumental hardness, meltability, and stretchability were kept as responses of the design. The study returned 30.96% of KCl and 2% of emulsifying salt to be optimum, and at these levels, the product had maximum sensory scores. Hardness, meltability, and stretchability of the product were reported to be 14.355 N, 21.68 cm and 15.07 cm, respectively. Further, the study was validated by manufacturing the product using optimized levels of ESs and KCl and comparing the actual responses with the responses predicted by RSM. No significant difference ( p > 0.05) between actual and predicted values validated the results of RSM. Full-sodium and low-sodium cheeses had 905 mg/100 g and 260 mg/100 g sodium, respectively. Thus, the study resulted in 71.27% reduction in overall sodium content of processed Mozzarella cheese. [ABSTRACT FROM AUTHOR]

Salt stress tolerance of durum wheat was assessed in control and 200 and 300 mM NaCl-exposed seed of two cultivars (BidiAP4 and Azizi). These salt treatments were accompanied by different levels of nitrate (Ca(NO 3) 2) added to the media (0.1, 3, 10 mM). The data showed that NaCl stress increased Na + and Cl − contents and lowered K + and NO 3− levels in seeds of BidiAP4 cultivar. In Azizi seeds exposed to NaCl, Na + and K + were highly accumulated while low levels of NO 3− and Cl − were detected. Those findings highlight the difference in the salt stress tolerance of these two durum wheat cultivars also depending on nitrogen (N) availability, Azizi cultivar being less sensitive to NaCl treatment than BidiAP4. These data also suggested a relationship between salt tolerance capacity and enhancement or maintenance of nitrogen and carbon metabolisms enzyme activity. [ABSTRACT FROM AUTHOR]

Transformations of (2 R*,3 R*)-2-[(1 R*)-1-iodoethyl)-3,5-dimethyl-1-(4-methylphenylsulfonyl-2,3-dihydro-1 H-indole on heating in boiling dimethylformamide in the presence of various salts were studied. [ABSTRACT FROM AUTHOR]

This paper reports the interaction of salt (NaCl and KCl), initial pH, and temperature and their effects on the specific growth rate and lag phase of food spoiling halotolerant yeast, Debaryomyces nepalensis. The optimization of salt, initial pH, and temperature was carried out using response surface methodology based on central composite design. The mathematical model showed that salt has a significant effect on specific growth rate and lag phase of D. nepalensis. The optimal conditions of salt concentration, pH, and temperature of growth were found to be 0.3 M NaCl, 7.1, 26 °C and 0.6 M KCl, 5.6, 25°C, respectively. Under these conditions, a maximum specific growth rate of 0.41 and 0.5 h was observed in medium containing NaCl and KCl, respectively. Lag phase can be increased most effectively either by increasing salt concentrations or both by decreasing (≤20°C) or increasing the temperature (≥40°C) with moderate (1.5 M) or low salt concentration (0.5 M), respectively. Results show that D. nepalensis need to generate weak acids to maintain the intracellular pH under pH and saline stress conditions. The results obtained in this study will be helpful in using optimal conditions for the maximum growth of the strain for the production of certain metabolites like organic acids and glycerol and designing food preservation procedures. [ABSTRACT FROM AUTHOR]

novel protease from the halophilic bacterium Geomicrobium sp. EMB2 (MTCC 10310) is described. The activity of the protease was modulated by salt, and it exhibited remarkable stability in organic solvents, at alkaline pH, and in other denaturing conditions. The structural changes under various denaturing conditions were analyzed by measurements of intrinsic fluorescence and circular dichroism spectroscopy. Circular dichroism showed that the secondary structure of the protease was predominantly α-helical but unfolded in salt-free medium. The structure is regained by inclusion of NaCl in the range of 2-5%. The presence of NaCl exerted a protective effect against thermal, organic solvent, and guanidine hydrochloride denaturation by preventing unfolding. [ABSTRACT FROM AUTHOR]

The effects of supplemental potassium were studied on growth, ion concentration and anatomical parameters in one year old olive trees, Olea europaea L., grown in sand culture in greenhouse at different levels of NaCl for 80 days. The experiments were conducted in a completely randomized design as a factorial. Factor one was salinity (0, 40 or 80 mM NaCl) and the second factor was potassium levels of 4 and 8 mM. Salinity caused a significant decrease in the growth of plants; however, the supplemental potassium could partly ameliorate the adverse effects of salinity on growth. Due to salinity Na+ and Cl- ions accumulated and the K+ /Na+ ratio decreased in the plants. The lower relative water content and the higher cortex /stele ratio in plants under salinity indicate water deficit. Under salinity, however, the supplemental potassium led to lower Na+ and higher K+ and P concentration which probably reduced the toxicity. The ratio of cortex to stele became normal as salt-grown plants were supplemented with potassium. Supplemental potassium increased palisade cell layer thickness in leaves under salinity that may be accompanied with increased potential for photosynthesis. The results indicate that supplemental potassium can be useful in ameliorating salinity stress effects in olive plants. [ABSTRACT FROM AUTHOR]

In this study we examined the short- and long-term impact of early life dietary sodium (Na) on prenatally programmed hypertension. Hypertension was induced in rat offspring by a maternal low protein (LP) diet. Control and LP offspring were randomized to a high (HS), standard (SS), or low (LS) Na diet after weaning. On the SS diet, the LP pups developed hypertension by 6 weeks of age. The development of hypertension was prevented by the LS diet and exacerbated by the HS diet. Kidney nitrotyrosine content, a measure of oxidative stress, was reduced by the LS diet compared with the HS diet. The modified diets had no effect on control pups. A group of animals on the SS diet was followed up to 51 weeks of age after an early life 3-week exposure to the HS or LS diet. This brief early exposure of LP animals to the LS diet prevented the later development of hypertension and ameliorated the nephrosclerosis observed after early exposure to the HS diet. The LP offspring with early exposure to LS diet had lost their salt-sensitivity when challenged with the HS diet at the age of 43–49 weeks. No effect of early life dietary Na was observed in control animals. These results show that hypertension in this model is salt sensitive and may, in part, be mediated by salt-induced renal oxidative stress and that there may exist a developmental window which allows postnatal “reprogramming” of the hypertension. [ABSTRACT FROM AUTHOR]

Common root rot caused by Cochliobolus sativus, is an economically important disease found worldwide. In in vitrostudies, the influence of salt on the growth and pathogenicity of C. sativuswas investigated using potato dextrose agar adjusted to different osmotic potentials with NaCl and KCl. Mycelial growth rates, colony diameter and germination decreased as salt concentrations increased, and NaCl caused greater negative effects than KCl. The high solute concentrations of NaCl and KCl (200–500 mM) reduced the synthesis of mycelial pigments and the size of conidia, while the production of spores was inhibited at 500 mM NaCl. Pathogenicity of C. sativuswas also significantly reduced in salt treatments compared with the untreated control and this reduction was greater in NaCl than in KCl. The tolerance of the common root rot pathogen to high salt concentrations provides important information about the survival of the fungus in saline areas. [ABSTRACT FROM AUTHOR]

Hormonal control of growth was examined in juvenile Mozambique tilapia Oreochromis mossambicus under different environmental salinities. When juvenile tilapia were acclimated to fresh water (FW) or to full-strength sea water (SW) for 3 weeks, growth rate of the SW-acclimated fish doubled compared to FW fish. Pituitary mRNA levels of growth hormone (GH) were significantly higher in SW-adapted tilapia compared with FW fish, while the gene expression of prolactin (PRL188 and PRL177) in SW fish was lower than in the FW group. The release and synthesis of insulin-like growth factor-I (IGF-I) were significantly elevated in the SW fish. This indicates that the GH/IGF-I axis is up-regulated in juvenile tilapia in SW and likely leads to the observed elevation in growth. Transfer of the juveniles from FW to 70% SW or vice versa for 2 weeks had no effect on growth rate. On the other hand, GH transcripts as well as hepatic IGF-I mRNA levels increased significantly after transfer of the FW-acclimated fish to 70% SW, while PRL188 mRNA levels were significantly elevated after transfer of the 70% SW fish to FW. Our findings indicate that the GH/IGF-I axis plays important roles both in growth and in osmoregulation in juvenile tilapia in SW. [ABSTRACT FROM AUTHOR]

The effects of temperature and salinity on growth of green algae Chlorella ellipsoidea and Nannochloris oculata were determined to compare the optimum culture conditions. A four-temperature (15, 20, 25, and 30°C) × three-salinity (10, 20, and 30) factorial design with triplicates was applied. Specific growth rate (SGR), maximum density, and duration to reach maximum density of C. ellipsoidea were significantly affected by both temperature and salinity. The highest SGR was observed in C. ellipsoidea at 25°C and salinity 10, but the maximum density was very low. The highest maximum density was achieved in C. ellipsoidea at 15°C and 10. The slope constant of the linear relationship between semilogarithmic growth of C. ellipsoidea and day of culture was highest at 15°C and 10. The SGR and duration to reach maximum density of N. oculata were significantly affected by both temperature and salinity. However, maximum density of N. oculata was significantly affected by temperature, but not salinity. The highest maximum density was achieved in N. oculata at 25°C and 30, but SGR was significantly lower than that of N. oculata at 25°C and 10. The slope constant of the linear relationship between semilogarithmic growth of N. oculata and day of culture was highest at 25°C and 30. Based on these results, the condition of 15°C and salinity 10 seemed to be optimal for maximum density of C. ellipsoidea, and the condition of 25°C and 10 and 30 for SGR and maximum density for N. oculata, respectively. [ABSTRACT FROM AUTHOR]

A systematic investigation of the effect of polyethylene glycols, salts, and alcohols on the trichloroacetic acid (TCA)-induced state of ferricytochrome c was made using various spectroscopic techniques. Native cytochrome c (Cyt c) has a fluorescence maximum at 335 nm, where as the TCA-induced state of Cyt c has a red shift of 7 nm with enhanced fluorescence intensity. The near-and far-UVCD spectra showed a significant loss of tertiary and secondary structure, although the protein is relatively less unfolded as compared with a conformation at pH 2.0. Addition of 70% (v/v) polyols to TCA (3.3 mM)-induced state of Cyt c resulted in increased 1-anilino-8-naphthalene sulfonate binding and increased mean residue ellipticity at 222 nm, indicating increase in compactness with enhanced exposure of hydrophobic surface area. Also, the stabilizing effect of salts and alcohols on the TCA-induced state was studied and compared with their effect on trifluoroacetic acid-unfolded state of Cyt c. Among all the polyols, salts, and alcohols studied, PEG-400, K3[Fe(CN)6], and butanol were the most efficient in inducing secondary structure in TCA-induced state as examined by the above-mentioned spectroscopic techniques. For salts, the efficiency in inducing the secondary structure followed the order K3[Fe(CN)6] > KClO4 > K2SO4 > KCl. For alcohols, this order was found to be as follows: butanol > propanol > ethanol > methanol. [ABSTRACT FROM AUTHOR]

Presents the topics discussed in the Third International Symposium on Perinatal Nephrology held in Strasbourg, France. Salt, blood pressure and hemodynamics in neonatology; Effect of a high- and low-salt diet on newborn infants; Role of the kidney in blood pressure control; Long-term implications of renal abnormalities on blood pressure; Ultrasound-Doppler investigation of renal hemodynamics in the newborn.

The article reports on the new 'Salt Strategy' launch by Great Britain Department of Health (DH) Public Health Minister Anna Soubry to reduce the amount of salt intake of people in the country in 2013.