Moderate Salt Research Articles

Bipolar membrane electrodialysis: A promising paradigm for caustic soda production

AbstractCurrently, a supply‐demand imbalance between NaOH and Cl2 in the chlor‐alkali process places a great burden on the environment. Bipolar membrane electrodialysis (BMED) is a competitive technology to produce acid and base due to its water splitting characteristics. To determine the competitiveness of NaOH production between BMED and the chlor‐alkali method, BMED was evaluated at various current densities with different NaCl concentrations. Results show that NaOH energy consumption in BMED is less than that of the chlor‐alkali method at a moderate salt concentration (<9 wt.%). Interestingly, the stack voltage suddenly increases during the later stage of BMED. It is speculated that the high osmotic pressure surrounding bipolar membranes restrains water transport into the interfacial layer. In addition, economic assessment indicates that BMED has less impact on global warming than the chlor‐alkali process. Overall, the BMED technique is a promising paradigm for base production in an economical and sustainable manner.

The Influence of Sodium Salt on Growth, Photosynthesis, Na+/K+ Homeostasis and Osmotic Adjustment of Atriplex canescens under Drought Stress

Atriplex canescens is widely cultivated as drought and salt-tolerant fodder in arid regions of Northwest China, which is used for photoremediation of degraded land and soil and water conservation. To explore the growth performance of A. canescens when exposed to drought and salt stress, seedlings were treated with a range of drought stress (WC1: 75 ± 3.6%, WC2: 49 ± 2.9% and WC3: 27 ± 2.5% of soil water content) and the corresponding drought stress with additional sodium salt supplementation (NaCl:Na2SO4 = 1:1 with the total concentration of Na+ set to 150 mM). The findings of this paper indicated that moderate sodium salt could stimulate the growth of A. canescens and effectively alleviate the deleterious impact of drought stress by increasing the turgor potential (ψt) and relative water content (RWC) and decreasing the leaf water osmotic potential (ψs). Furthermore, the photosynthetic capacity was improved and the negative effects of drought stress on photosystem II (PSII) were mitigated. The extra 150 mM sodium salt also markedly increased the contribution of Na+ to ψs and the contribution of betaine to ψs. In summary, these results indicate that A. canescens can adapt to drought stress by accumulating enough Na+ for osmotic adjustment (OA). Additionally, this paper is aimed to provide a fundamental basis for the utilization and cultivation of A. canescens as a favored pasture crop in the Qaidam basin, thus increasing the ecological and environmental benefits for arid regions worldwide.

Comparison of Salt Stress Tolerance among Two Leaf and Six Grain Cultivars of Amaranthus cruentus L.

Amaranths (Amaranthus L.) are multi-use crop species renowned for their nutritional quality and their tolerance to biotic and abiotic stresses. Since the soil salinity of croplands is a growing problem worldwide, we tested the salinity tolerance of six grain and two leaf cultivars of Amaranthus cruentus L. The plants were grown for 53 days under hydroponic conditions at 0, 50 and 100 mM NaCl. We investigated the growth rate, photosynthetic activity, mineral content, pigments and biochemical compounds involved in oxidative stress. Although 100 mM NaCl always decreased biomass production, we highlighted Don Leon and K91 as tolerant cultivars under moderate salt stress (50 mM NaCl). Under salinity, sodium accumulated more in the shoots than in the roots, particularly in the stems. Sodium accumulation in the plants decreased the net photosynthetic rate, transpiration rate and stomatal conductance but increased water use efficiency, and it decreased chlorophyll, betalain and polyphenol content in the leaves. It also decreased the foliar content of calcium, magnesium and potassium but not the iron and zinc content. The physiological parameters responded differently to sodium accumulation depending on the cultivar, suggesting a different relative importance of ionic and osmotic phases of salt stress among cultivars. Our results allowed us to identify the morpho-physiological traits of the cultivars with different salt tolerance levels.

Contribution of Arbuscular Mycorrhizal Fungi (AMF) in Improving the Growth and Yield Performances of Flax (Linum usitatissimum L.) to Salinity Stress

Throughout the world, salinity is a major environmental issue that limits agricultural productivity, particularly in arid and semi-arid regions. In addition, climate change is the most important reason for the salinization of agricultural soils in the world, so it is now essential to find solutions to increase salinity tolerance in plants. This study investigated the potential of arbuscular mycorrhizal fungi (AMF) inoculation to enhance the growth and yield performances of flax under different salinity levels by conducting a pot experiment. The experiment was laid out in a two-factor completely randomized design including AMF inoculation (AMF+: with inoculation; AMF−: without inoculation) and irrigation water salinity (0, 50, 100, and 150 mM NaCl). According to the results, it is evident that salt stress caused negative physiological effects, including limited growth, reduced photosynthesis, and decreased nitrogen (N) and phosphorus (P) content in the shoots and roots of flax plants. Moreover, mycorrhizal association improved the salt tolerance of the plants by increasing chlorophyll content, and enhancing N and P shoot and root contents and consequently yield parameters, such as seed and stem fiber yield, particularly at moderate salt concentrations (50 and 100 mM NaCl). In particular, under 100 mM, AMF increased the total chlorophyll content, N shoot and root content, P shoot and root content, and seed and stem fiber yield by 30.4%, 36.1%, 31.0%, 38.9%, 45.4%, 35.2%, and 26.9%, respectively. As a result of using AMF, flax plants grown under salt stress exhibited tolerance, suggesting that AMF could be applied in saline environments to maintain ecological stability.

Moderate salt spraying on grapevine canopy induces differential modulation of anthocyanin synthesis profiles during early and late stages of berry ripening in Cabernet Sauvignon

Moderate salt spraying on grapevine canopy induces differential modulation of anthocyanin synthesis profiles during early and late stages of berry ripening in Cabernet Sauvignon

Impact of dark septate endophytes on salt stress alleviation of tomato plants.

Fungal endophytes can improve plant tolerance to abiotic stress conditions. Dark septate endophytes (DSEs) belong to phylogenetically non-related groups of root colonizing fungi among the Ascomycota with high melanin-producing activities. They can be isolated from roots of more than 600 plant species in diverse ecosystems. Still the knowledge about their interaction with host plants and their contribution to stress alleviation is limited. The current work aimed to test the abilities of three DSEs (Periconia macrospinosa, Cadophora sp., Leptodontidium sp.) to alleviate moderate and high salt stress in tomato plants. By including an albino mutant, the role of melanin for the interaction with plants and salt stress alleviation could also be tested. P. macrospinosa and Cadophora sp. improved shoot and root growth 6 weeks after inoculation under moderate and high salt stress conditions. No matter how much salt stress was applied, macroelement (P, N, and C) contents were unaffected by DSE inoculation. The four tested DSE strains successfully colonized the roots of tomato, but the colonization level was clearly reduced in the albino mutant of Leptodontidium sp. Any difference in the effects on plant growth between the Leptodontidium sp. wild type strain and the albino mutant could, however, not be observed. These results show that particular DSEs are able to increase salt tolerance as they promote plant growth specifically under stress condition. Increased plant biomasses combined with stable nutrient contents resulted in higher P uptake in shoots of inoculated plants at moderate and high salt conditions and higher N uptake in the absence of salt stress in all inoculated plants, in P. macrospinosa-inoculated plants at moderate salt condition and in all inoculated plants except the albino mutants at high salt condition. In summary, melanin in DSEs seems to be important for the colonization process, but does not influence growth, nutrient uptake or salt tolerance of plants.

Phytochemical, Morphological, and Physiological Variation in Different Ajowan (Trachyspermum ammi L.) Populations as Affected by Salt Stress, Genotype × Year Interaction and Pollination System.

In the present research, 28 populations of ajowan (Trachyspermum ammi L.) were evaluated for agro-morphological traits and essential oil yield in two consecutive years. Then, selected ajowan populations from these two years were used for further morphophysiological and biochemical studies under different salinity levels (control, 60, 90, and 120 mM NaCl). The main components of the oil were thymol (32.7-54.29%), γ-terpinene (21.71-32.81%), and p-cymene (18.74-26.16%). Salt stress caused an increase in essential oil content in the Esfahfo and Qazvin populations. The highest total phenolic and flavonoid contents were found in the Arak population grown in 60 mM NaCl (183.83 mg TAE g-1 DW) and the Yazd population grown in 90 mM NaCl (5.94 mg QE g-1 DW). Moreover, the Yazd population exhibited the strongest antioxidant activity based on DPPH (IC50 = 1566 µg/mL) under 60 mM NaCl and the highest reducing power (0.69 nm) under 120 mM NaCl. The results revealed that low and moderate salt stress improves the phytochemicals of ajowan seeds, which are useful for pharmaceutical and food applications. In this research, some morphological traits, as well as essential oil yield, were evaluated in open pollinated versus self-pollinated plants. As a result, plant height, number of flowering branches, and crown diameter significantly decreased in some populations, while a significant increase was obtained for number of flowers per umbel and seed numbers per umbel. Finally, self-pollination of ajowan might provide new insights for further breeding programs to increase oil or thymol content in ajowan.

Addition of fish oil microcapsules to meat products – Implications for omega-3 enrichment and salt reduction

This study aimed to evaluate the effect of fish oil microcapsules on saltiness perception of burger meats and to develop acceptable ω-3 with reduced salt. The addition of fish oil microcapsules in combination to moderate salt reduction and cooking significantly increased the quantity of ω-3 fatty acids, the acceptability, and the salty taste. These effects had a slight influence on lipid oxidation levels, or instrumental colour parameters (L*, a*, b*). The addition of fish oil microcapsules (4.5–6.5 %) in combination with salt reduction may be recommended to develop acceptable meat products labelled with nutrition claims related to sodium/salt (“reduced salt” or “low salt content”) and omega-3 (“source of omega-3 fatty acids” or “rich in omega-3 fatty acids”).

SALT RESTRICTION COMBINED WITH RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM BLOCKADE IS A POTENT ANTIHYPERTENSIVE STRATEGY IN PATIENTS WITH PRIMARY ALDOSTERONISM

Objective: The relationship between high dietary salt intake and high blood pressure is well established. Recommendations for salt restriction have found their way into major guidelines for essential hypertension. Patients with primary aldosteronism (PA), the most common endocrine cause of arterial hypertension, are believed to be exquisitely salt sensitive, i.e., respond particularly well to salt restriction. However, surprisingly little efforts have been made to determine the precise impact of salt restriction in patients with PA. We, therefore, set out to implement a moderate salt restriction in patients with PA to assess its impact on blood pressure and secondary health outcomes. Design and method: We used nutritional education and continuous self-monitoring via a smartphone app to reduce salt intake in 41 patients with PA for a time span of 12 weeks. All patients were on mineralocorticoid receptor antagonist therapy and had stable blood pressure. Patients were monitored every 4 weeks with blood pressure and urine sampling and detailed blood work at weeks 0 and 12. Mental well-being was addressed by validated scoring systems. Results: Patients achieved a significant reduction of dietary salt intake (from 9.1 to 5.2 g/d) and of blood pressure (from 130/84 to 121/81 mmHg). We also registered a significant loss of body weight (-1.4 kg). While subjects initially featured PHQD scores compatible with depression, scores normalized at the end of the study. Multivariate regression analysis revealed that cumulative intake of drugs targeting the renin-angiotensin-aldosterone system was an independent predictor of blood pressure reduction. Conclusions: Salt restriction is an effective treatment in patients with PA. Patient empowerment by education and self-monitoring promotes salt restriction. Effects are facilitated by concomitant RAAS blockade. Salt restriction, despite being moderate, also improves mental well-being.

Lake water chemistry and population of origin interact to shape fecundity and growth in Daphnia ambigua.

Freshwater environments vary widely in ion availability, owing to both natural and anthropogenic drivers. Field and laboratory work point to the importance of overall salinity, as well as cation depletion, in shaping the physiology, behavior, and ecology of freshwater taxa. Yet, we currently have a poor understanding of the degree to which populations may vary in response to ion availability. Using Daphnia collected from three lakes that differ greatly in salinity and calcium availability, we conducted a laboratory reciprocal transplant experiment to assess how animals representing these populations vary in fecundity, body size, and survival when reared in lake water from each environment. The lake water environment and population of origin strongly interacted to shape Daphnia growth and reproduction. Surprisingly, we found only modest evidence that lake water with abundant calcium (5.5 vs. 1.2-2.3 mg/L) increased Daphnia growth or reproduction. By contrast, water from a relatively ion-rich lake (400 μS/cm specific conductance) strongly boosted Daphnia fecundity over lower-ion lake water (20-50 μS/cm), especially for the population originating from the high-ion environment. Our results suggest that ion-poor conditions common in regions around the world may exert stress on freshwater organisms, even for populations inhabiting these environments. Meanwhile, moderate salt enrichment may not prove harmful but could even benefit freshwater taxa in these ion-poor regions. The context dependence of how and when lake water chemistry affects Daphnia and other freshwater taxa deserves greater attention, in both ion-depleted and ion-rich conditions. Daphnia are key members of lake food webs and serve as an important model for ecology, evolution, and toxicology research. Consideration of how lake water chemistry may influence how Daphnia populations respond to abiotic and biotic stress may improve the ability to evaluate and predict ecological and evolutionary dynamics in lakes of varying chemical composition.

Spider Plant (Cleome gynandra L.): An Emerging Weed in the Sweet Corn–Brassica Cropping System

Spider plant (Cleome gynandra L.) is an emerging noxious weed, affecting cultivated vegetables in Queensland, Australia. It is a prolific seed producer, forming large seedbanks with variable seedling emergence. A study was carried out to investigate the seed biology of spider plant, focusing on its seed germination ecology, viz., influence of temperatures, illumination conditions, medium salinity, pH, substrate moisture, burial depth, and after-ripening. Freshly harvested seeds were negatively photoblastic and had combinational dormancy. Improved germination was obtained by physical scarification followed by soaking for 16 h, by dry storage for over 6 months, and by the imbibition of gibberellic acid. Maximum germination percentages of 70 to 80% were recorded under constant darkness at alternating day/night temperatures of 20/30 °C, or with 18 to 27 °C constant temperatures. Spider plant showed a broad tolerance to pH but only moderate salt and moisture stress tolerance, since only 42 and 26% germination were observed with 60 mM NaCl and at −0.40 MPa, respectively. Seeds placed on the soil surface did not germinate, however, at a burial depth of 1.0 to 1.5 cm, which resulted in ca. 80% seedling emergence. These findings will assist land managers to predict seasonal emergence and will aid in deploying management approaches to control this weed.

Salt stress altered anaerobic microbial community and carbon metabolism characteristics: The trade-off between methanogenesis and chain elongation

Discharge of saline organic wastewater is increasing worldwide, yet how salt stress disrupts the microbial community's structure and metabolism in bioreactors has not been systematically investigated. The non-adapted anaerobic granular sludge was inoculated into wastewater with varying salt concentration (ranging from 0% to 5%) to examine the effects of salt stress on the structure and function of the anaerobic microbial community. Result indicated that salt stress had a significant impact on the metabolic function and community structure of the anaerobic granular sludge. Specifically, we observed a notable reduction in methane production in response to all salt stress treatments (r = −0.97, p < 0.01), while an unexpected increase in butyrate production (r = 0.91, p < 0.01) under moderate salt stress (1–3%) with ethanol and acetate as carbon sources. In addition, analysis of microbiome structures and networks demonstrated that as the degree of salt stress increased, the networks exhibited lower connectance and increased compartmentalization. The abundance of interaction partners (methanogenic archaea and syntrophic bacteria) decreased under salt stress. In contrast, the abundance of chain elongation bacteria, specifically Clostridium kluyveri, increased under moderate salt stress (1–3%). As a consequence, the microbial carbon metabolism patterns shifted from cooperative mode (methanogenesis) to independent mode (carbon chain elongation) under moderate salt stress. This study provides evidence that salt stress altered the anaerobic microbial community and carbon metabolism characteristics, and suggests potential guidance for steering the microbiota to promote resource conversion in saline organic wastewater treatment.

A stratagem for primary root elongation under moderate salt stress in the halophyte Schrenkiella parvula.

Schrenkiella parvula, an Arabidopsis-related halophyte, grows around Lake Tuz (Salt) in Turkey and can survive up to 600 mM NaCl. Here, we performed physiological studies on the roots of S. parvula and A. thaliana seedlings cultivated under a moderate salt condition (100 mM NaCl). Interestingly, S. parvula germinated and grew at 100 mM NaCl, but germination did not occur at salt concentrations above 200 mM. In addition, primary roots elongated much faster at 100 mM NaCl, while being thinner with fewer roots hair, than under NaCl-free conditions. Salt-induced root elongation was due to epidermal cell elongation, but meristem size and meristematic DNA replication were reduced. The expression of genes related to auxin response and biosynthesis was also reduced. Application of exogenous auxin abolished the changes in primary root elongation, suggesting that auxin reduction is the main trigger for root architectural changes in response to moderate salinity in S. parvula. In A. thaliana seeds, germination was maintained up to 200 mM NaCl, but post-germination root elongation was significantly inhibited. Furthermore, primary roots did not promote elongation even under fairly low salt conditions. Compared to A. thaliana, cell death and ROS content in primary roots of salt-stressed plants were significantly lower in S. parvula. These changes in the roots of S. parvula seedlings may be an adaptive strategy to reach lower salinity by advancing into deeper soils, while being impaired by moderate salt stress. This article is protected by copyright. All rights reserved.

Moderate Salinity Stress Increases the Seedling Biomass in Oilseed Rape (Brassica napus L.).

Oilseed rape (Brassica napus L.), an important oil crop of the world, suffers various abiotic stresses including salinity stress during the growth stage. While most of the previous studies paid attention to the adverse effects of high salinity stress on plant growth and development, as well as their underlying physiological and molecular mechanisms, less attention was paid to the effects of moderate or low salinity stress. In this study, we first tested the effects of different concentrations of NaCl solution on the seedling growth performance of two oilseed rape varieties (CH336, a semi-winter type, and Bruttor, a spring type) in pot cultures. We found that moderate salt concentrations (25 and 50 mmol L-1 NaCl) can stimulate seedling growth by a significant increase (10~20%, compared to controls) in both above- and underground biomasses, as estimated at the early flowering stage. We then performed RNA-seq analyses of shoot apical meristems (SAMs) from six-leaf-aged seedlings under control (CK), low (LS, 25 mmol L-1), and high (HS, 180 mmol L-1) salinity treatments in the two varieties. The GO and KEGG enrichment analyses of differentially expressed genes (DEGs) demonstrated that such a stimulating effect on seedling growth by low salinity stress may be caused by a more efficient capacity for photosynthesis as compensation, accompanied by a reduced energy loss for the biosynthesis of secondary metabolites and redirecting of energy to biomass formation. Our study provides a new perspective on the cultivation of oilseed rape in saline regions and new insights into the molecular mechanisms of salt tolerance in Brassica crops. The candidate genes identified in this study can serve as targets for molecular breeding selection and genetic engineering toward enhancing salt tolerance in B. napus.

Reduction of Excessive Dietary Sodium Consumption: Effectiveness of a Prevention Intervention among Health Workers in a Large Italian Hospital.

Excessive salt consumption is one of the leading causes of high blood pressure. Worldwide salt intake largely exceeds the WHO recommended amount. This study aimed to evaluate the prevalence of high salt consumers and the effectiveness of a short-term workplace educational intervention among health workers. An online survey, assessing daily salt consumption through the MINISAL-SIIA questionnaire, was sent to the 4911 health workers employed by the University Hospital of Verona, Italy. Health workers who had a high (total score ≥ 10) or moderate (total score = 8/9) salt consumption associated with obesity or arterial hypertension were invited to undergo a medical examination and a short individual counselling session. A total of 1665 health workers (34.0%) completed the online questionnaire; 40.9% and 12.6% had moderate and high salt intake, respectively. High salt intake was more prevalent in men, current and past smokers, and obese and overweight subjects. In 95 participants completing the clinical phase, median daily salt consumption decreased from 10 (p25-p75 8-11) to 7 g (6-8) (p < 0.001), systolic blood pressure from 130 (120-140) to 120 (120-130) mmHg and weight from 78 (62-87) to 75 (62-86) kg. More than half of health workers had an excessive salt intake. However, a brief educational intervention in the healthcare working setting can substantially reduce unhealthy dietary habits, fostering weight loss and blood pressure control. Studies with a longer follow-up are needed to evaluate the persistence over time of these effects.

Appropriateness of Land and Crop Selection for an Area in Iraq Al-Salamiyat

Al-Salamiyat project, which is situated inside the administrative boundaries of Baghdad Governorate and has a total size estimated at 2621 hectares, required a study to assess the lands for cereal crops (wheat, barley, and maize). The study region was visited and examined repeatedly in order to set up and gather data; take soil models; observe the land cover; the level of soil salinity; the kind of agricultural use; and the planted crops. The internodes project was covered by satellite imagery retrieved from the satellite sentinel (2B) Al-Mashhad (SMC) for the month of March 2021. The soil model’s physical and chemical characteristics were estimated. The analyses’ findings demonstrated that the research area’s soils had a degree of interaction (PH), as estimated values for this characteristic ranged from 7.05 for soil model No. 8 to 7.9 for model No. 11, or neutral to medium basal. Because most of the study area’s lands are used for agriculture and have a high percentage of vegetative cover, the majority of the soils there contain modest amounts to moderately moderate salt. Carbonate minerals factor: According to Sys et alsuggestions.’s from 1993, the carbonate minerals factor estimations for wheat and barley harvests were 95% for all soils of the study area, and the final estimates for maize yield ranged from 60% to 85%. According to the findings, the estimations of the amount of exchanged sodium in the study area’s soils were a non-specific factor for the growth of the chosen crops and were given an estimate higher than 95%.. The evaluation of the soil’s properties for the research area’s specified crops showed that the (S1) variety is extremely suited for growing wheat, barley, and yellow corn due to the absence of determinants, while the (S2) class is moderate and acceptable for growing wheat and maize due to high salinity.

Moderate dietary salt restriction improves blood pressure and mental well-being in patients with primary aldosteronism: The salt CONNtrol trial.

Primary aldosteronism (PA) is a frequent cause of hypertension. Aldosterone excess together with high dietary salt intake aggravates cardiovascular damage, despite guideline-recommended mineralocorticoid receptor antagonist (MRA) treatment. To investigate the antihypertensive impact of a moderate dietary salt restriction and associated physiological changes, including mental well-being. A total of 41 patients with PA on a stable antihypertensive regimen-including MRA-followed a dietary salt restriction for 12 weeks with structured nutritional training and consolidation by a mobile health app. Salt intake and adherence were monitored every 4 weeks using 24-h urinary sodium excretion and nutrition protocols. Body composition was assessed by bioimpedance analysis and mental well-being by validated questionnaires. Dietary salt intake significantly decreased from 9.1 to 5.2g/d at the end of the study. In parallel, systolic (130 vs. 121mmHg) and diastolic blood pressure (BP) (84 vs. 81mmHg) improved significantly. Patients' aptitude of estimating dietary salt content was refined significantly (underestimation by 2.4 vs. 1.4g/d). Salt restriction entailed a significant weight loss of 1.4kg, improvement in pulse pressure (46 vs. 40mmHg) and normalization of depressive symptoms (PHQD scale, p<0.05). Salt restriction, cortisol after dexamethasone suppression test and dosage of renin-angiotensin-aldosterone-system (RAAS) blockers were independently associated with BP reduction. A moderate restriction of dietary salt intake in patients with PA substantially reduces BP and depressive symptoms. Moreover, the findings underline that a sufficient RAAS blockade seems to augment the effects of salt restriction on BP and cardiovascular risk.

The ENA1 Na+-ATPase Gene Is Regulated by the SPS Sensing Pathway and the Stp1/Stp2 Transcription Factors.

The Saccharomyces cerevisiae ENA1 gene, encoding a Na+-ATPase, responds transcriptionally to the alkalinization of the medium by means of a network of signals that involves the Rim101, the Snf1 and PKA kinases, and the calcineurin/Crz1 pathways. We show here that the ENA1 promoter also contains a consensus sequence, located at nt -553/-544, for the Stp1/2 transcription factors, the downstream components of the amino acid sensing SPS pathway. Mutation of this sequence or deletion of either STP1 or STP2 decreases the activity of a reporter containing this region in response to alkalinization as well as to changes in the amino acid composition in the medium. Expression driven from the entire ENA1 promoter was affected with similar potency by the deletion of PTR3, SSY5, or simultaneous deletion of STP1 and STP2 when cells were exposed to alkaline pH or moderate salt stress. However, it was not altered by the deletion of SSY1, encoding the amino acid sensor. In fact, functional mapping of the ENA1 promoter reveals a region spanning from nt -742 to -577 that enhances transcription, specifically in the absence of Ssy1. We also found that the basal and alkaline pH-induced expression from the HXT2, TRX2, and, particularly, SIT1 promoters was notably decreased in an stp1 stp2 deletion mutant, whereas the PHO84 and PHO89 gene reporters were unaffected. Our findings add a further layer of complexity to the regulation of ENA1 and suggest that the SPS pathway might participate in the regulation of a subset of alkali-inducible genes.

Electrocapacitive Deionization: Mechanisms, Electrodes, and Cell Designs

AbstractCapacitive deionization (CDI) is an emerging water desalination technology for removing different ionic species from water, which is based on electric charge compensation by these charged species. CDI is becoming popular because it is more energy‐efficient and cost‐effective than other technologies, such as reverse osmosis and distillation, specifically in dealing with brackish water having low or moderate salt concentrations. Over the past decade, the CDI research field has witnessed significant advances in the used electrode materials, cell architectures, and associated mechanisms for desalination applications. This review article first discusses ion storage/removal mechanisms in carbon and Faradaic materials aided by advanced in situ analysis techniques and computations. It then summarizes research progress toward electrode materials in terms of structure, surface chemistry, and composition. More still, it discusses CDI cell architectures by highlighting their different cell design concepts. Finally, current challenges and future research directions are summarized to provide guidelines for future CDI research.

S-28-6: URINARY METABOLOMICS, DIETARY SALT INTAKE AND BLOOD PRESSURE: THE AFRICAN-PREDICT STUDY

Objective: Excessive salt intake is the leading dietary risk factor for cardiovascular disease (CVD). This increased risk may be attributed to alterations in the human metabolome. Salt sensitivity is associated with ethnicity, and ethnic differences in the interaction between sodium intake and the metabolome may play an integral part in CVD development. We therefore investigated 1) the urinary metabolomic profiles of Black and White adults according to low, moderate and high dietary salt intake; and 2) explored the relationships of identified metabolites with blood pressure. Design and Methods: This study included data of White (N = 447) and Black (N = 380) adults aged 20 to 30 years from the African-PREDICT study. Estimated salt intake was determined from 24hr urinary sodium. Urinary amino acids and acylcarnitines were measured using liquid chromatography tandem mass spectrometry. Clinic, 24hr and central systolic blood pressure (SBP) were measured. Results: Whites with a high salt intake (&gt; 10 g/day) had higher SBP (clinic, 24hr and central) compared to those with low (&lt; 5 g/day) or moderate (5 to 10 g/day) salt intakes (all p &lt; 0.05). The metabolites GABA (q = 0.020), citrulline (q = 0.020), glutamic acid (q = 0.046), serine (q = 0.054) and proline (q = 0.054) were lower in those with higher salt intake. In stepwise multivariable adjusted regression analyses, we found that clinic SBP of white adults were inversely associated with GABA (Adj. R2 = 0.35; Std. β=-0.123; p = 0.005), serine (Adj. R2 = 0.35; Std. β=-0.099; p = 0.022) and proline (Adj. R2 = 0.35; Std. β=-0.099; p = 0.021), and central SBP with GABA (Adj. R2 = 0.34; Std. β=-0.094; p = 0.036), glutamic acid (Adj. R2 = 0.34; Std. β=-0.090; p = 0.035) and proline (Adj. R2 = 0.034; Std. β=-0.106; p = 0.015). In Black adults, there were no differences in SBP or metabolites between low, moderate or high salt intake groups, with no relationships between SBP and GABA, glutamic acid, citrulline, serine or proline. Conclusion: In White adults, high salt intake was associated with low levels of GABA, glutamic acid, serine and proline, which in turn were related to high SBP. We hypothesise that metabolomic changes are related to salt intake and may contribute to pathophysiological mechanisms associated with increased blood pressure.