Sodium Chloride Concentration Research Articles

Salinity-responsive key endophytic bacteria in the propagules of Kandelia obovata enhance salt tolerance in rice

Salinity is a major environmental stress affecting crop growth and productivity globally. The application of halo-tolerant plant growth-promoting bacteria (HT-PGPB) has been widely recognized to promote crop growth and reduce the adverse effects of salt stress. Herein, key endophytic bacteria that can respond to salinity changes were identified by analysis of the microbial community in propagules of Kandelia obovate. Delftia tsuruhatensis DYX29, a strain able to grow normally under high salinity conditions with a sodium chloride (NaCl) concentration of 5% (w/v), was obtained by pure culture. DYX29 has the ability to produce siderophores with a siderophore unit value of 87.6% and ACC (1-aminocyclopropane-1-carboxylate) deaminase with 29 U L-1 and can synthesize intracellular amino acids and auxin induced by high salinity. Inoculation with DYX29 can remarkably promote the salt tolerance of rice. Under salt stress, the addition of DYX29 effectively promoted the growth of rice seedlings through a variety of approaches. It increased the biomass of rice seedlings by 32.9% (dry weight) and promoted the accumulation of soluble sugars by 23.1%. It also increased CAT and POD activities in rice leaves by 37.8 and 88.2%, respectively. Moreover, it maintained ionic homeostasis in roots and leaves. In addition, it upregulated the expression of growth-promoting hormones in roots, such as IAA, BL, ABA and SA, in rice roots by 27.8, 69.5, 123.7 and 28.6%, respectively. This study provides inspiration for screening valuable salt-tolerant pro-biotic bacteria from mangrove ecosystems for crop growth promotion under salt stress. It may also provide useful references for the development of new salt-tolerant and pro-biotic biofertilizers and the investigation of the related mechanism.

Resposta germinativa de sementes de jacarandá-caroba e aroeira-vermelha ao estresse salino e aplicação de ácido salicílico

Abstract Abiotic stresses, such as salinity, interfere with the growth and development of plants and can reduce, delay, or even inhibit the germination of the seeds. The knowledge about ornamental plants tolerance to those factors and the search for alternatives that reduce those effects, as is the use of salicylic acid, indicate paths to better development of the plants in environments affected by those stresses. This work aimed to evaluate the germination of Caroba-tree seeds and Brazilian peppertree seeds in different saline concentrations of sodium chloride (NaCl), using salicylic acid, as a possible saline stress attenuator. The experimental design utilized was completely randomized, with treatments arranged in factorial scheme 4 x 2 being four saline concentrations (0, 30, 60, and 90 mM of NaCl) combined with the absence (immersion in distilled water) or presence of salicylic acid (immersion in a solution containing salicylic acid at 1.0 mM). It was concluded that Caroba-tree showed moderate tolerance to salinity promoted by NaCl during seed germination. The average germination percentage was 83.91%. However, the seeds germinated at slower paces with the increasing saline solutions. The application of salicylic acid at the concentration of 1.0 mM did not influence the germination percentage of seeds subjected to saline solutions, regardless of the concentration. However, the seeds germinated faster in the absence of salicylic acid. Brazilian peppertree was not tolerant to salinity promoted by NaCl, with an average germination percentage of 47% and 40%, respectively, for the absence and presence of salicylic acid.

Metods for creating salt – tolerant long – grin varieties in Karakalpakstan

The article presents the results of breeding methods for creating salt-tolerant long – grain rice varieties. For this purpose, collection samples and the best varieties of rice from different ecological and geographical zones were studied according to agrobiological characteristics in comparison with the zoned ultra-early ripening long – grain varieties “Sanam”. After a comprehensive study and comprehensive assessment in the field conditions, ultra-early ripening long-grain forms with positive traits and properties were identified. These selected varieties were assessed far salt tolerance in laboratory conditions during the seed germination phase in an artificially created 1.5% solution (NaCl) of sodium chloride. A high concentration of sodium chloride has an adverse effect on germination rates and seedling size. At high concentrations of saline solution, these indicators sharply decrease in all studied varieties. However, such a decrease, depending on the genotypic characteristics of the variety samples, does not occur to the same extent. Under saline conditions, the characteristic differences between the characteristic of the seedling and the root system changes greatly. The growth and formation of roots was particularly inhibited compared aboveground part of the seedlings. Changes in the performance of the root system in a saline environment for the better can be considered adaptive properties to stressful salinity conditions. Based on the study of germination and seedling parameters, the most salt-tolerant varieties were identified, including Almaz; D-42 (D-11) 35-05-2); D-134 (D-34) (D-143); D-61 (K-316) Viktoriya). These varieties successfully overcome the adverse effects of high concentrations, of sodium chloride solution.

Extraction of acid orange 7 from water by emulsion liquid membrane using Tri-dodecyl-amine as extractant

The main objective of this study was to investigate the feasibility of extracting Acid Orange 7 (AO7), a complex reactive dye, from aqueous solutions using a stabilized emulsion liquid membrane (ELM) technique. The ELM formulation comprised tri-dodecylamine (TDA) as the extracting agent, kerosene as the diluting medium, and SPAN 80 as the surfactant. We systematically examined various experimental variables that affect the extraction of AO7. These variables included the concentrations of the extractant and surfactant, internal phase concentrations, the ratio of the membrane phase to the internal phase, the choice of diluting medium and its grade, stirring speed, treatment ratio, and the initial concentration of AO7. Furthermore, we investigated the impact of sodium chloride concentration in the external phase. Our research findings indicate that the optimal conditions for AO7 extraction using the ELM method were as follows: a TDA concentration of 3% (w/w), a SPAN 80 concentration of 9% (w/w), an oil-to-aqueous phase ratio (O/A) of 1:1, kerosene as the diluting medium, H2SO4 as the internal phase, a stirring speed of 200 rpm, a treatment ratio of 1:10, and an initial AO7 concentration of 10 mg/L. Under these precise conditions, an exceptional extraction efficiency of 98.49% was achieved in just 15 min. Under these carefully controlled conditions, an exceptional extraction efficiency of 98.49% was achieved in just 15 min. Consequently, the emulsified liquid membrane extraction process demonstrates significant potential as an advanced separation technique for removing hazardous dyes, particularly in dilute solutions.

Detection of Toxoplasma gondii in artisanal salted meat products sold in street markets of the Ilhéus-Itabuna microregion.

This study aimed to detect Toxoplasma gondii in artisanal salted meat products sold in street markets in the Ilhéus-Itabuna microregion and to assess the salt concentration used in their preparation and its influence on the parasite's viability. A total of 125 samples of various artisanal meat products sold in street markets located in the Ilhéus-Itabuna microregion were collected during 2021. Serological analysis using indirect hemagglutination (HAI) and molecular analysis (PCR) were performed on these samples to detect the presence of the parasite. Möhr's method was utilized to determine the sodium chloride concentration in the samples. Of all samples, 21 were subjected to a bioassay in albino mice to verify the viability of possible tissue cysts. Among the 125 meat products, 10 (8%) tested positive in the serological analysis including four cured pork sausages, five beef sun-dried meats, and one mixed fresh sausage (pork and chicken). None of 125 samples tested positive in the molecular analysis. On bioassay, all mice tested negative for the presence of the parasite. The NaCl concentration in the positive samples ranged from 2.9% to 8%. The results demonstrated that the salt concentration in the collected samples was sufficient to inactivate the parasite T. gondii.

Fatty acid composition of Kashkaval cheese with reduced sodium chloride content

The aim of the present study was to investigate the changes in the fatty acid profile and acid value of milkfat during ripening of Kashkaval cheese with reduced sodium chloride content. Three batches of Kashkaval cheese (with low 0.7%; medium 1.5% and standard 3.1% NaCl content) were produced. Analyses were carried out on days 1 and 45 of ripening. Based on the results obtained, it was established that lipolysis in Kashkaval cheese during ripening was significantly delayed (p<0.05) in all samples. A slight increase in Kashkaval fatty acid value during ripening was established. Not statistically significant changes in the fatty acid composition of the tested samples during the 45-day ripening period were found. The average values for saturated fatty acids (SFA) were 81.08 mg/100g and for the monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) were 11.03 and 1.04 mg/100g between control group (KSs with 3.1% NaCl content) and experimental groups (KMs with reduced NaCl content of 1.5% and KLs with a low NaCl content of 0.7 %) respectively. The predominant fatty acids (FA) were palmitic (C16, 37.56±1.13 mg/100g), myristic (C14, 16.98±0.51 mg/100g), stearic (C18, 15.35±0.46 mg/100g) and oleic acid (C18:1, 10.47±0.31 mg/100g). At the end of the ripening period, Kashkaval cheese with low content of NaCl had a slightly higher acid value of 3.03±0.58 mg KOH/g in comparison with cheese samples with medium and standard NaCl content of 1.72±0.01 and 1.11±0.01 mg KOH/g respectively.

Separation and Purification Residual Salt from Glycerine Pitch from Waste of Refined Glycerine Production

The glycerol refining process produces 5%wt/ton waste in the form of glycerine pitch (GP) and has the potential to pollute the environment if not properly handled and expensive handling costs. In this study, GP was characterized by its chemical composition and spectroscopic analysis using FTIR and UV-Vis. The sodium chloride content of 15-30% contained in GP was separated and purified by solid-liquid extraction. Solvent selection (methanol, ethanol and acetone), solvent ratio (1:3, 1:5 and 1:10) and extraction time (10, 15 and 30 min) were evaluated using one factor at the time (OFAT) method. The methanol was found to be the optimum solvent and the best ratio at 1:5 produced sodium chloride purity around 81%. However, the effect of extraction time was declared not significant with a pvalue above 0.05. The TOC result of residual salt was 44 ppm and residual methanol content was not detected after heating. The integrated process of separation and purification of residual salt from GP is easy to apply and zerowaste potential in organic waste after extraction can be achieve by combustion in boiler with a calorific value obtained of 3000-3200 cal/g.

Hyponatremia in the Elderly Induced by Risperidone: A Case Report

Hyponatremia due to risperidone is a rare complication that can be associated with drowsiness, confusion to coma and seizures. We report a case of a 92-year-old female with delirium combined with pulmonary infection who developed severe hyponatremia after 30 days of risperidone treatment, and the patient’s blood sodium gradually increased to normal after administration of concentrated sodium chloride, tolvaptan and gradual reduction of risperidone dosage until discontinuation. Through clinical observation, the mechanism of hyponatremia caused by risperidone is related to the Syndrome of Inappropriate Antidiuretic Hormone (SIADH).

Üç Farklı Kuşak Florokinolon Türevinin Ratlarda Eritrosit Frajilite ve Hematolojik Parametreler Üzerindeki Etkilerinin Araştırılması

Objektive: Fluoroquinolones (FQs) are synthetic broad-spectrum antimicrobial agents derived from nalidixic acid. They are used in the treatment of urinary tract infections, respiratory tract infections, skin infections, digestive system infections, genital infections and other bacterial infections. Although the relationship between FQs and oxidative stress has been demonstrated, their effects on erythrocyte fragility have not been adequately studied. In this study, the effects of three different FQ derivatives (ciprofloxacin (CIP), levofloxacin (LVX) and moxifloxacin (MXF)) on erythrocyte fragility and hematological parameters were investigated in rats at the end of the 1st, 7th and 14th day treatments.
 Material and Method: 72 Wistar albino male rats were divided into 4 groups with 18 rats in each group and sacrificed at three different time points (1st, 7th and 14th days).
 Results: A significant increase in 0.2% sodium chloride (NaCl) concentration erythrocyte fragility value was found in the MXF group on 1st day compared to the control group on 1st day. While the FQ derivatives used in the study did not cause a general change on the erythrocyte and leukocyte parameters, they caused various fluctuations on the platelet parameters such as PCT, PLCR, PDW, MPW and PLT.
 Conclusion: As a further study, it would be beneficial to reveal the reasons for these effects on platelet parameters with more detailed studies.

Comparison of the effect of Sodium Chloride concentration on protein determination: Bradford and Biuret methods

Protein quantification methods using spectrophotometry are widely used in laboratory routines for different purposes. Samples generally contain non-protein components that can interfere with the quality of the analysis. A simple and quick test with different concentrations of sodium chloride demonstrated that the Bradford method is significantly affected by the presence of salt, while Biuret remains stable. Therefore, the choice of method is an important factor in reducing errors and ensuring more reliable results.

Analysis of brines for the content of the main substance and impurities of magnesium and calcium salts by the sonoluminescence method

The use of the sonoluminescence method for the analysis of brines for the content of the main substance – sodium chloride and admixtures of magnesium and calcium salts – was studied. The use of sonoluminescence initiated by the ultra-high frequency ultrasound (10.0–25.0 MHz) to determine the content of the main substance – sodium chloride – in brines, as well as sonoluminescence initiated by the simultaneous action of ultra-high- (10.0–25.0 MHz) and low- (20–100 kHz) frequency ultrasound to determine the content of magnesium and calcium salts was experimentally investigated. When determining the content of sodium chloride in brines, the smallest relative standard deviation of the analysis results (Sr = 0.010–0.013) was when using the ultra-high-frequency ultrasound with a frequency of 22.0–23.0 MHz and intensity of 20.0 W/cm2. When determining the content of magnesium and calcium salts, for the initiation of sonoluminescence, it was optimal to use the simultaneous action of ultra-high frequency ultrasound (20.0–22.0 MHz) and intensity (20.0 W/cm2), and low-frequency ultrasound (19.0–22.0 kHz) and intensity 1.30–1.50 W/cm2, which made it possible to increase the sensitivity of determining magnesium and calcium in brines from 3.0–5.0 g/l when initializing sonoluminescence by the low-frequency ultrasound to 0.01 g/l when initializing sonoluminescence by the simultaneous action of ultra-high- and low-frequency ultrasound.
 Methods for determining the content of the main substance and impurities of magnesium and calcium salts in brines have been developed. The correctness of the methods was checked by analysing the same samples using alternative methods. When determining the content of the main substance, the following methods were used as alternative ones: gravimetry and the sonoluminescence method of low-frequency ultrasound, as well as with high-frequency ultrasound. When determining the content of magnesium and calcium salts, flame atomic absorption spectrometry and the sonoluminescence method of low-frequency ultrasound, as well as with the simultaneous action of high- and low-frequency ultrasound, were used as alternative methods.

Effect of Sodium Chloride Concentration on Cooking Time Calculation and Sensory Evaluation of Fish Sausage

This research was conducted to evaluate the effect of the addition of sodium chloride (NaCl) at different concentrations (0–3.0%) on the theoretical and real cooking time and sensory evaluation of the fish sausage. The fish sausage was prepared using 2:1.2:1 minced fish, sago starch, and water with added NaCl at a concentration of 1.5% to the formulation, and the sausage was cooked for 180 seconds (3 min) at 180°C to accomplish both the correct cooking time and sensory evaluation properties. Theoretical and real cooking time methods were calculated using a pre-calibrated thermocouple to reach the target core temperature of 75oC at the centre of the sausage. The optimum NaCl concentration and cooking time were identified from the cooking methods and sensory evaluation. The results revealed that increasing the addition of NaCl to the sausage formulations significantly increased the core temperature of the sausage during cooking. There was a reverse relationship between the added percentage of sodium chloride and the calculated cooking time; as the addition of sodium chloride increased, a shorter cooking time was obtained until we reached the target core temperature of 75oC. The predicted cooking time was 195.171 seconds, and the real cooking time was 180 seconds.

Describing the permeability of permanganate co-ions in a CEM with varying supporting electrolyte concentrations

Redox flow batteries (RFBs), a promising technology for large-scale power grid energy storage, utilize a membrane separator to facilitate an ionic current while preventing mixing of the anolyte and catholyte solutions. The anolyte and catholyte of an RFB each contain an electroactive species, and usually an additional supporting electrolyte to charge balance the anode and cathode redox reactions and reduce overall ohmic losses. This study investigates the impact of the supporting electrolyte concentration and composition on Nafion’s transport properties using permanganate as the permeant. The permanganate concentration was kept constant at 0.1m, while sodium chloride and sodium hydroxide were both studied as supporting electrolytes. The sodium chloride concentration was varied from 0.1m to 4.0m, while the sodium hydroxide concentration was varied from 0.1m to 10m. The permanganate permeability, water sorption coefficient, and salt sorption coefficients were measured for Nafion, with a peak permeability being observed at a supporting electrolyte concentration of 1m for both electrolytes. A framework to describe the observed behavior was derived using first principles to determine the transport coefficients under these conditions. It was found that at low concentrations, the permanganate permeability is controlled by Donnan exclusion and salt sorption, while at high concentrations it is controlled by salt diffusion and osmotic deswelling.

Improving the technology of waxes obtaining from oil and fat waste

The object of the research is the extraction of waxes from the waste of the oil and fat industry – spent perlite. As a result of oil winterization, a significant amount of spent filter powders is formed, the disposal of which poses a danger to the environment. At the same time, winterization waste contains a significant amount of oil and wax, which are important components of many types of products. Oil and wax extraction involves the use of volatile, fire-hazardous solvents. An urgent task is to develop new safe and effective technologies for obtaining oils and waxes from winterization waste. The technology of extracting waxes from spent perlite, obtained as a result of winterization of sunflower oil, which involves treatment of perlite with sodium chloride solution, was investigated. Perlite was used according to SOU 15.4-37-210:2004 (CAS Number 93763-70-3) with indicators: mass fraction of fat – 20.1 %, peroxide value – 19.5 ½ O mmol/kg, acid value – 3.5 mg KOH/g. The temperature of mass settling after treatment with sodium chloride is 20 °C, the duration – 10 hours. The following rational conditions for perlite processing using sodium chloride were determined: the concentration of dry sodium chloride (by weight of perlite) – 35.0 %, the duration of mass boiling – 30 minutes. Under these conditions, the experimental value of the saponification value of the obtained wax was 120.5 mg KOH/g. Wax quality indicators: melting point 71.5 °C, acid value 1.6 mg KOH/g, mass fraction of moisture 0.63 %. The obtained results make it possible to obtain high-quality waxes from the waste of the oil and fat industry using a safe and affordable substance (sodium chloride). This will make it possible to avoid the need for waste disposal and increase the profitability of oil and fat enterprises due to obtaining valuable products from production waste

Thermo-mechanical behavior of reconstituted deep-water sediments

Understanding the thermo-mechanical behavior of deep-water sediments is essential for the safe design of high-temperature oil/gas pipelines. In this study, a series of temperature-controlled triaxial tests was conducted to investigate the thermo-mechanical behavior of reconstituted deep-water sediments sampled from the South China Sea. The experimental results revealed the thermo-mechanical behavior of sediments was closely related to their thermo-mechanical loading paths and sodium chloride (NaCl) concentrations. The increasing rate of excess pore water pressure decreases with an increase in temperature increment, effective confining pressure, and overconsolidation ratio, regardless of NaCl concentration. For normally consolidated specimens, the undrained shear strength generally decreases as temperature increases. The undrained shear strength of specimens was lower under undrained heating and higher under drained heating than that at 5 °C, respectively. Factors such as thermal softening, thermal consolidation, and thermal-induced excess pore water pressure significantly impacted the undrained shear strength of sediments under isothermal, drained, and undrained heating conditions. Additionally, the undrained shear strength decreases with increasing NaCl concentration. The results highlighted that the critical state line is unique under varying loading paths and NaCl concentrations. Furthermore, the effect of changes in void ratio induced by NaCl solution on the shear strength of sediments was more pronounced than that of the intergranular stress.

Fermentation and valorization of watermelon (Citrullus lanatus) rind wastes into livestock feed using Aspergillus niger and Mucor sp.

Agro-industrial wastes pose environmental health hazards to humans and animals; yet, they are abundant, readily availabile and cheap, and therefore provide opportunities for their valorization with microorganisms to produce value-added, nutrient-rich animal feed. This study (i) determined, in vitro, optimum growth conditions for Aspergillus niger and Mucor sp. and (ii) subsequently evaluated their ability to ferment and valorize watermelon wastes for protein enhancement. Changes in protein contents of sterilized and unsterilized watermelon substrates were determined after 5, 10, and 15 days of fermentation with mono- and co-cultures of A. niger and Mucor sp. at 25 °C. Different growth conditions (pH, temperature, different concentrations of ammonium nitrate, sodium nitrate, urea, sodium chloride and thiamine) of synthetic media variously supported mycelial growth of A. niger and Mucor sp., either as mono- or co-culture; optimum growth conditions were selected for fermentation of watermelon wastes. Protein contents of sterilized and unsterilized watermelon substrates were enhanced by fermentation: (i) percentage increase in protein contents of sterilized watermelon fermented with mono-cultures of A. niger, Mucor sp. and co-culture of A. niger and Mucor sp. were 35.91, 18.94 and 22.18 %, respectively; (ii) protein contents in unsterilized watermelon substrates also increased by 23.94, 9.49, and 14.88 % for mono-cultures of A. niger and Mucor sp. and their co-culture, respectively. Overall, the observed trend in the increase of protein contents in the sterilized and unsterilized substrates by the test fungi was: mono-culture of A. niger > co-culture of A. niger and Mucor sp. > mono-culture of Mucor sp. Crude fat, fiber and ash contents significantly (p ≤ 0.05) decreased in both sterilized and unsterilized watermelon substrates, whereas the carbohydrate content increased significantly (p ≤ 0.05) in the substrates. These findings highlight the potential of watermelon waste as valuable bioresource and feedstock for valorization into livestock feed through fungal biotechnology. Future works to augment findings are suggested.

Polymeric ionic liquid sorbent coatings in thin film microextraction: Insight into sorbent selectivity for pesticides and cannabinoids

Polymeric ionic liquid (PIL) sorbent coatings consisting of polymerizable cations and anions were employed as sorbent coatings in thin film microextraction (TFME) for the extraction of pesticides and cannabinoids. The blades consisted of a thin film of PIL sorbents chemically bonded to vinyltrimethoxysilane-functionalized nitinol sheets. The imidazolium- or ammonium-based PIL sorbents contained aromatic benzyl moieties as well as polar hydroxyl groups or aliphatic functional groups within the chemical structure of the IL monomer. The chemical structure of the IL crosslinkers of the PILs were kept constant across each sorbent, except for the anion, which consisted of either bis[(trifluoromethyl)sulfonyl]imide ([NTf2−]), p-styrenesulfonate ([SS−]), or 3-sulfopropyl acrylate ([SPA−]). Temperature, salt content, and methanol content were optimized as extraction conditions to maximize pesticide-cannabinoid selectivity using Doehlert design of experiments (DOE). Effects of these three factors on selectivity and extraction efficiency are discussed. The optimal extraction conditions consisting of sample temperature (31°C), sodium chloride (30% w/v), and methanol content (0.25% v/v) are compared to initial sorbent screening conditions at a sample temperature of 40°C, 15% (w/v) sodium chloride, and 2.5% (v/v) methanol content. PIL sorbent swelling behavior at different salt and methanol content conditions and its effect on extraction efficiency are hypothesized. Selectivity factors for the sorbents indicated that aromatic moieties within the IL monomer may enhance pesticide-cannabinoid selectivity under optimized conditions, but the extraction efficiency of pesticides that are known to coelute with cannabinoids in the chromatographic separation may be enhanced by employing sorbent coatings with [SPA−] anions.

Angular surface plasmon resonance-based sensor with a silver nanocomposite layer for effective water pollution detection

For sensing various samples of polluted water and various sodium chloride concentrations using an angular surface plasmon resonance (ASPR), we have introduced a conventional structure and a hybrid heterostructure in the current research. The suggested structures are composed of silver metal, dielectric layers, silver nanocomposite, and a sensing medium. The reflectance spectra of all structures in the visible region were obtained through the utilization of the transfer matrix method by using the angular interrogation method depending on the Kretschmann configuration. Through our findings, five substrate parameters have been optimized to attain the utmost level of sensitivity across all structures: the thickness of Ag-metal, the type and thickness of dielectric materials, the host material type and the volume fraction of nanoparticles for the nanocomposite layer. In this regard, the suggested sensor provides excellent performance with a sensitivity of 448.1°/RIU\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$/\ ext{RIU}$$\\end{document}, signal-to-noise ratio of 0.787, sensor resolution of 0.284°, and figure of merit of 78.766 RIU−1. Therefore, we believe that the introduced design of our ASPR sensor presents a good candidate for an accurate and efficient detection of low concentrations of contaminated water and sodium chloride as well.

Flotation of copper-bearing shale at different pH values of solutions and sodium chloride concentrations

Flotation of copper-bearing shale in aqueous solutions of NaCl at their different pH values was investigated. The tests were carried out in a laboratory flotation machine. The pH range was between 5 and 10 while NaCl concentrations were 0.5M, 1.0M and 2.0M. It was observed that the flotation recovery of the copper shale was increasing with the increase of pH and concentration of the salt solution. On the basis of thermodynamic and hydrodynamic considerations it was postulated that the increasing surface tension was responsible for better shale flotation observed with increasing salt concentration. The observed improved shale flotation caused by increasing pH is most likely due to changes in the properties of the thin film between particle and bubble including mosaic structure of water on the surface of shale. It was shown that the zeta potential of shale particles, zeta potential of air bubbles, solution surface tension, and shale hydrophobicity were not responsible for the increasing with pH recoveries.

The model of functional disorders in rats with kidney nephrectomy ¾ in comparison with a high-salt diet

BACKGROUND. Modeling of chronic kidney disease using nephrectomy of 5/6 kidney parenchyma is actively used in experimental nephrology. However, the remaining 17 % of the organ parenchyma is associated with severe renal fibrosis in humans. A high-salt diet has traditionally been considered as a systemic hemodynamic model for the development of chronic kidney disease.THE AIM: to compare the functional disorders that occur in rats with nephrectomy of ¾ of the kidneys and when using only a high-salt diet.MATERIAL AND METHODS. The study was performed on 30 male Wistar rats. The animals were randomly divided into 3 equal groups: control (falsely operated, L), high-salt diet (falsely operated, LVD), nephrectomy ¾ renal parenchyma (NE). The rats received a balanced laboratory feed daily, differing only in the content of sodium chloride (NaCl). In the L and NE groups, rats received a feed containing 0.34 % NaCl, and in the VD group – 4 % NaCl. The duration of follow-up was 16 weeks. Systolic blood pressure (SBP) was measured on the tail by the cuff method. The serum and urine concentrations of creatinine, urea, potassium, sodium, chlorine, as well as the degree of proteinuria and albuminuria were determined.RESULTS. During the observation, the SBP in group L did not change. In the LVD group, SBP increased from 120 [120; 125] mmHg to 130.0 [125.0; 140.0] mmHg, p=0.011. In the NE group, SBP also increased from 120 [120; 125] mmHg to 135.0 [132.5; 137.5] mmHg, p=0.011. In the LVD group, there was an increase in serum creatinine concentration compared to the control to 52.5 [50.0; 56.0] mmol/l, p=0.0001; urea to 6.0 [5.6; 6.6] mmol/l, p=0.0001; potassium to 5.6 [5.3; 5.8] mmol/l, p=0.0001; chlorine up to 87.5 [86.6; 87.9] mmol/l, p= 0.0001. At the same time, creatinine clearance decreased from 187.5 [160.0; 205.0] ml/min in the L group to 92.0 [81.2; 99.0] ml/min, p=0.0003 in the LVD group and to 83.9 [65.7; 85.9] ml/min p=0.0001 in the NE group. The value of albuminuria before the end of the experiment was statistically significantly higher compared to the control in both the LVD group of 12.12 [6.36;18.41] mg/g creatinine, p= 0.0001, and in the NE group of 72.5 [61.6; 92.9] mg/g creatinine, p= 0.0001. When conducting a nonparametric correlation analysis (all three observation groups were combined), a statistically significant relationship was noted between the level of SBP after 1 month from the start of the experiment and the amount of albuminuria at its completion (Rs=0.583 p=0.001). A statistically significant relationship between the value of SBP and creatinine clearance was revealed before the end of the experiment (Rs=-0.700 p=0.005). Also, before the end of the experiment, a statistically significant relationship between albuminuria and creatinine clearance was revealed (Rs=-0.671 p=0.006).CONCLUSION. The NE model of the renal parenchyma is expected to be accompanied by the development of less severe functional changes compared to NE 5/6 of the renal parenchyma. In this regard, we assume that its use may be useful in studying the effectiveness of nephroprotective measures at the initial stages of CKD development. The negative effects of a high-salt diet are comparable in a number of indicators to nephrectomy of the renal parenchyma. Traditionally, an increase in salt intake is associated with an increase in blood pressure, which could result in an increase in albuminuria. However, we could not identify any relationships between albuminuria and the value of SAD. We assume that the model of a high-salt diet can be considered as a variant of a local, rather than a systemic hemodynamic model of the development of chronic kidney disease. In the future, we will present the results of nephrobiopsy in the experimental groups described above.