Addition Of CaCl2 Research Articles

The summer sprays of iodine with calcium chloride are successful in biofortifying apples with iodine and improving their storability

ABSTRACT This study investigated the impacts of spraying iodine (I) as potassium iodide (KI) and K-iodate (KIO3) with/without calcium chloride (CaCl2) on apple (Malus domestica Borth.) enrichment with I as well as on fruit quality. ‘Idared’ apple trees were sprayed with I: (i) in the summer, five times at a rate of 0.1 kg ha−1 in each treatment with or without CaCl2 and (ii) preharvest (2 weeks before harvest) at a rate of 0.5 kg ha−1. Iodine concentrations in apples sprayed with this nutrient in the summer varied from 41 to 70 µg 100 g−1 FW. The preharvest I sprays increased apple I concentrations up to 63–69 µg 100 g−1 FW. Only the addition of CaCl2 to the spray solution containing KIO3 enhanced fruit I concentration. The sprays of I with CaCl2 increased apple Ca concentration as well as flesh firmness and contents of organic acids in fruit after storage. The percentage of I losses did not differ between combinations, averaging 11.3%. It is concluded that the summer sprays of KI or KIO3 with CaCl2 should be recommended to biofortify apples with I and improve their Ca-related storability.

Ion-pairing equilibria and kinetics of dimethyl phosphate: A model for counter-ion binding to the phosphate backbone of nucleic acids

Dimethyl phosphate (DMP–) is the simplest model ion to assess ion-pairing phenomena between metal ions and the phosphate backbone of nucleic acids. Yet, the equilibria and dynamics of ion binding to DMP– have not been fully uncovered. Here, we study the interaction of DMP– with different cations and water in aqueous solutions of NaDMP using dielectric relaxation and nuclear magnetic resonance spectroscopies. We find DMP– to be weakly hydrated and weakly associated with Na+ in the absence of added salt. Upon addition of NaCl, MgCl2, or CaCl2 to solutions of NaDMP, we detect the formation of solvent-shared (NaDMP0) and contact (MgDMP+, CaDMP+) ion-pairs; the degree of ion association is 20–27 % at 2:1 salt:DMP molar ratio for the bivalent ions. Comparison to literature results suggests the formation constant of MgDMP+ to be a good estimate for the binding of Mg2+ to RNA. From the concentration dependence of the rotational relaxation time of the ion-pairs, we find ion-pair dissociation rates to follow the order Mg2+≪Ca2+<Na+. Strikingly, our data suggest that the overall ion-pair dissociation dynamics are governed by an ion-pair metathesis reaction, which provides a different pathway for the binding of ions by DMP–.

Effect of CaCl2, Al(OH)3 and NH4H2PO4 and their dosages on the explosion intensity of pulverized coal

ABSTRACT In this paper, the TGA-DSC curve of coal powder explosion inhibitors was analyzed. At the same time, the influence of the explosion inhibitor type and mass fraction on the five explosion intensity parameters of pulverized coal Pex,(dp/dt)ex,Kst,t1 , and t2 was explored. The results show that CaCl2 and NH4H2PO4 go through three main stages: dehydration stage, decomposition stage and crystal transformation stage after high-temperature heating. Calcium chloride absorbs heat through the process of water volatilization and crystal transformation to prevent the combustion of pulverized coal. Meanwhile, NH4H2PO4 absorbs heat through decomposition, evaporation and sublimation reactions to prevent the combustion of pulverized coal. For these two explosion inhibitors, the explosion intensity of pulverized coal decreases with the increase of mass fraction. The increase of Al(OH)3 mass fraction basically does not enhance its explosion suppression effect. After adding NH4H2PO4, the maximum decrease of Pex was 32.08%, which was 11.89% and 16.99% higher compared to the addition of CaCl2 and Al(OH)3, respectively. The maximum decrease of (dp/dt)ex was 98.47%, which was 29.45% and 33.38% higher compared to the addition of CaCl2 and Al(OH)3, respectively. Therefore, the order of explosion suppression performance was determined as: NH4H2PO4 > CaCl2 > Al(OH)3.

Efficient separation and recovery of lithium through volatilization in the recycling process of spent lithium-ion batteries

Spent lithium-ion batteries (LIBs) comprise different kinds of valuable metals with recovery and reuse value. Aiming to address the difficulty of recycling lithium from spent LIBs through conventional pyrometallurgy, a new method of high-efficiency separation and recovery of lithium through volatilization is proposed. In this new method, spent LIBs as the raw material, copper slag as the only flux and CaCl2 as an additive are utilized to recover lithium from spent LIBs. Under the optimal conditions, the volatilization rate of Li was 96.87%. During the smelting process, lithium is volatilized into the gas phase in the form of LiCl, where lithium can be recycled from the dust. In light of the experimental results, the addition of CaCl2 contributes to the formation of LiCl. The kinetics study showed that the volatilization of LiCl was controlled by an interfacial chemical reaction, and the apparent activation energy was 42.57 kJ/mol. In addition, Li2CO3 could be obtained from lithium-containing dust using a precipitation process. This method achieves efficient separation of lithium during the reduction smelting process. The phase transformation and kinetics of the separation process were investigated, and reaction mechanism was revealed. Importantly, the novel process provides new ideas and perspectives for the separation of lithium from spent LIBs through a pyrometallurgical process.

High-Protein Foods for Dysphagia: Manipulation of Mechanical and Microstructural Properties of Whey Protein Gels Using De-Structured Starch and Salts.

This study focuses on understanding the effect of ionic strength on the mechanical and microstructural properties of novel composite gels containing 13% whey protein isolate (WPI) and 4% de-structured waxy potato starch (DWPS). The DWPS is a physically modified waxy potato starch treated at 140 °C for 30 min under constant shear. Thermodynamic incompatibility between WPI and DWPS was observed upon the addition of NaCl (~75 mM) or CaCl2 (10–75 mM). The combined effects of such thermodynamic incompatibility with the changes in protein connectivity induced by varied ionic strength led to the formation of distinctive gel structures (inhomogeneous self-supporting gels with a liquid centre and weak gels with paste-like consistency) that were different from thermodynamic compatible homogeneous self-supporting gels (pure WPI and WPI + maltodextrin gels). At ≥ 250 mM NaCl, instead of a paste-like texture, a recovered soft and creamy self-supporting gel structure was observed when using DWPS. The ability to generate a range of textures in WPI gelation-based foods by using DWPS under different ionic conditions, is a feasible strategy for formulating high-protein foods for dysphagia—aimed to be either thickened fluids or soft solids. Additionally, this acquired knowledge is also relevant when formulating food gels for 3-D printing.

Electro-Assisted 3D Printing Multi-Layer PVDF/CaCl2 Composite Films and Sensors

Polyvinylidene fluoride (PVDF) films are widely used in sensors for their wide response frequency, good flexibility, low acoustic impedance, and chemical stability. In this work, PVDF/CaCl2 piezoelectric films were prepared by an electro-assisted 3D printing method and used to form a multi-layer composite film sensor. The study found that the addition of CaCl2 can effectively increase the β-phase content in the PVDF film and improve the piezoelectric and dielectric properties of the PVDF composite film sensors. When the content of CaCl2 is 0.15 wt.%, the β-phase content of the PVDF/CaCl2 composite film can reach the highest value of up to 48.47%, and the output voltage response of the sensor is 0.62 V at an input frequency of 10 Hz, 10 V voltage. The output voltage of PVDF composite film sensor with two and three layers is 1.306 and 1.693 times that of a single layer, respectively. The sensitivity of the multi-layer sensors has also been greatly improved.

Osteogenic activities of four calcium-chelating microalgae peptides.

Adequate calcium intake is necessary to prevent osteoporosis, which poses significant public health challenges. The natural bioactive peptide calcium chelates have been regarded as superior calcium supplements. Microalgae peptides are regarded as potential candidates for protection from bone loss in osteoporosis. This study aimed to prepare microalgae calcium-chelating peptides from four microalgae proteins and assess their osteogenic activities in osteoporosis-like zebrafish. After in vitro gastrointestinal digestion, 4.42% Chlorella pyrenoidosa protein, 2.74% Nannochloropsis oceanica protein, 6.07% Arthospira platensis protein and 10.47% Dunaliella salina protein were retained. The calcium-chelating capacities of four microalgae protein hydrolysates (MPHs) ranged from 14.10 ± 7.16%to 34.11 ± 9.34%. CaCl2 addition increased the maximum absorption peaks, absorption intensities and particle sizes of MPHs. Calcium-chelating MPHs showed stronger osteogenic activities than MPHs in the osteoporosis-like zebrafish model, with significantly increased mineralized tissue area and integrated optical density. Microalgae proteins have favorable digestibilities. Among the four MPHs, Nannochloropsis oceanica protein hydrolysates showed the highest calcium-chelating capacity, which might be due to its high degree of hydrolysis after in vitro digestion and high content of Ser, Tyr, Thr, Asp and Glu. The absorption intensities and particle sizes of MPHs both increased after calcium addition. MPH treatment could reverse dexamethasone-induced osteoporosis of zebrafish, and MPHs-Ca chelates showed higher osteogenic activities in osteoporosis-like phenotype zebrafish. © 2022 Society of Chemical Industry.

Experiment on the Properties of Soda Residue-Activated Ground Granulated Blast Furnace Slag Mortars with Different Activators.

Soda residue (SR), a solid waste generated in the production of Na2CO3 during the ammonia soda process, with a high pH value of 12, can be used as an activator of alkali-activated ground granulated blast furnace slag (GGBFS) cementitious materials. Three groups of experiments on SR-activated GGBFS mortars were designed in this paper to assess the role of the dominant parameters on fluidity and compressive strength of mortars. The results indicate that for fluidity and mechanical properties, the optimal scheme of SR-activated GGBFS mortars is 16:84–24:76 S/G, 0.01 NaOH/b, 0.05 CaO/b, and 0.50 w/b, with fluidity and compressive strength (28 d) of the mortars being 181–195 mm and 32.3–35.4 MPa, respectively. Between 2.5–10% CaCl2 addition to CaO (5%)-SR (24%)-activated GGBFS mortar is beneficial to the improvement of the compressive strength of C2, whereas the addition of CaSO4 is harmful. The main hydration products of mortars are ettringite, Friedel’s slat, and CSH gels. The results provide a theoretical basis and data support for the utilization of SR.

Integration of the transcriptome and proteome provides insights into the mechanism calcium regulated of Ulva prolifera in response to high-temperature stress

Heat stress is one of the most remarkable abiotic factors limiting the growth and productivity of Ulva prolifera. The calcium signalling pathway plays an important role in the plant heat resistance response. However, the physiology and molecular mechanisms by which the calcium signalling pathway regulates the U. prolifera response to high temperature remain largely unknown. Changes in the physiology, transcriptome, and proteome of U. prolifera in response to high temperature were investigated with exogenous application of CaCl2 (denoted UpCa) and the calmodulin (CaM) inhibitor W-7 (N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride, denoted UpW7) to fill this gap. In total, 33,475 differentially expressed genes (DEGs) and 869 differentially expressed proteins (DEPs) were identified between the control and UpCa treatments. At the mRNA level, the upregulated DEGs were enriched in the RNA transport, mRNA surveillance, carotenoid biosynthesis, basal transcription factor, porphyrin and chlorophyll metabolism, diterpenoid biosynthesis, and flavonoid biosynthesis pathways. The downregulated DEGs were enriched in photosynthesis, plant hormone signal transduction, photosynthesis-antenna proteins, and oxidative phosphorylation. At the protein level, upregulated proteins were enriched in alpha-linolenic acid metabolism, photosynthesis-antenna proteins, and plant–pathogen interactions. The downregulated proteins were enriched in endocytosis, mismatch repair, ribosomes, RNA degradation, and spliceosomes. The addition of exogenous CaCl2 induced the expression of peroxidase, heat shock 70, heat shock 90, nuclear pore complex protein Nup62, MFS transporter, calcium-dependent protein kinase, calcium/calmodulin-dependent protein kinase kinase 1, calcium-binding protein calmodulin-like (CML), Ca2+-transporting ATPase, and serine/threonine-protein kinase at both the mRNA and protein levels. In addition, the same downregulated DEPs and DEGs were correlated and included the ApaG protein, chaperonin GroEL, proteasome inhibitor subunit 1 (PI31), serine/arginine repetitive matrix protein 1, glutamine synthetase, and F-type H+-transporting ATPase subunit alpha. The addition of W7 inhibited Ca2+-related gene expression, and the expression of genes and proteins involved in phagosome, photosynthesis-antenna proteins, RNA transport, plant–pathogen interactions, protein processing in the endoplasmic reticulum, and protein export were downregulated. However, exogenous CaCl2 and W7 increased the expression of TFs, such as Myb and G2-like. In a subsequent study, the addition of CaCl2 significantly increased and W7 significantly inhibited catalase and superoxide dismutase activity in U. prolifera under high-temperature stress. The expression of the CaM gene was significantly increased at 24 h in U. prolifera under high-temperature stress; CaCl2 and W7 significantly inhibited the expression of the CaM gene.In summary, Ca2+ activated Ca2+-related channels to regulate downstream transcript and response proteins; however, the addition of Ca2+ and W7 inhibited photosynthesis. These results provide insights into the mechanism by which calcium increases the mechanical strength of U. prolifera in response to high-temperature stress.

Effects of calcium ions on anionic polyacrylamide fouling of ion-exchange membranes in desalination of polymer-flooding wastewater by electrodialysis

The effects of calcium ions (Ca2+) on anionic polyacrylamide (APAM) fouling of ion-exchange membranes (IEMs) in the treatment of polymer-flooding wastewater (PFW) from oil production industry by electrodialysis were systematically investigated by associating the desalination performance, physicochemical and electrochemical characteristics with the electrostatic interaction and interfacial free energy. Bench-scale experiments were performed under constant current conditions to investigate the fouling mechanisms with different molecular weights (MWs). It was found that APAM fouling mainly occurred on the anion-exchange membranes (AEMs) due to electrostatic attraction, which significantly deteriorated the membrane desalination performance. The membrane fouling of APAM with a MW of 6 million Dalton (600APAM) was more serious than that of 0.5 million Dalton (50APAM), and APAM fouling on homogeneous membranes was more serious than that on heterogeneous membranes. Ca2+ would connect with the carboxylate ions of APAM by coordination. The electrostatic attraction between APAM molecules and AEM weakened due to increasing zeta potential after CaCl2 addition. And as a result, the APAM+Ca fouling formed intricate and compact aggregates sparsely distributed on the surface of AEMs compared to the APAM fouling layer. Both electrostatic interactions and interfacial free energy affected APAM fouling of IEMs, but electrostatic interactions dominated the fouling process.

Hofmeister Effects of Group II Cations as Seen in the Unfolding of Ribonuclease A.

This work studies the effects of alkaline-earth cation addition on the unfolding free energy of a model protein, pancreatic Ribonuclease A (RNase A) by differential scanning calorimetry analysis. RNase A was chosen because: a) it does not specifically bind Mg2+ , Ca2+ and Sr2+ cations and b) maintains its structural integrity throughout a large pH range. We have measured and compared the effects of NaCl, MgCl2 , CaCl2 and SrCl2 addition on the melting point of RNase A. Our results show that even though the addition of group II cations to aqueous solvent reduces the solubility of nonpolar residues (and enhances the hydrophobic effect), their interactions with the amide moieties are strong enough to "salt-them-in" the solvent, thereby causing an overall protein stability reduction. We demonstrate that the amide-cation interactions are a major contributor to the observed "Hofmeister Effects" of group II cations in protein folding. Our analysis suggests that protein folding "Hofmeister Effects" of group II cations, are mostly the aggregate sum of how cation addition simultaneously salts-out hydrophobic moieties by increasing the cavitation free energy, while promoting the salting-in of amide moieties through contact pair formation.

Calcium acts as a central player in melatonin antitumor activity in sarcoma cells

PurposeChondrosarcoma and osteosarcoma are the most frequently occurring bone cancers. Although surgery and chemotherapy are currently clinically applied, improved treatment options are urgently needed. Melatonin is known to inhibit cell proliferation in both tumor types. Although the underlying mechanisms are not clear yet, calcium homeostasis has been reported to be a key factor in cancer biology. Here, we set out to investigate whether regulation of calcium by this indolamine may be involved in its antitumor effect.MethodsCell viability was measured using a MTT assay and flow cytometry was used to measure levels of cytosolic calcium, intracellular oxidants, mitochondrial membrane potential and cell cycle progression. Mitochondrial calcium was analyzed by fluorimetry. Cell migration was determined using a scratch wound-healing assay. Western blot analysis was used to assess the expression of proteins related to cell cycle progression, epithelial to mesenchymal transition (EMT), Ac-CoA synthesis and intracellular signaling pathways.ResultsWe found that melatonin decreases cytosolic and mitochondrial Ca2+ levels, intracellular oxidant levels, mitochondrial function and the expression of the E1 subunit of the pyruvate dehydrogenase complex. These changes were found to be accompanied by decreases in cell proliferation, cell migration and EMT marker expression. The addition of CaCl2 prevented the changes mentioned above, while co-treatment with the calcium chelator BAPTA enhanced the effects.ConclusionsOur data indicate that regulation of calcium homeostasis is a key factor in the inhibition of cell proliferation and migration by melatonin. This effect should be taken into consideration in combined therapies with traditional or new antitumor compounds, since it may circumvent therapy resistance.

Emulsion gels loaded with pancreatic lipase: Preparation from spontaneously made emulsions and assessment of the rheological, microscopic and cargo release properties

Emulsion gels are solidified emulsions, which can be used for delivery of both hydrophilic and lipophilic substances. In this research, at first fish oil-in-water (O/W; 10% w/w) emulsions were prepared through the spontaneous emulsification technique. As emulsifier, a blend of the small-molecule surfactant tween 80, and either low-acyl (LaG) or high-acyl (HaG) gellan was used. For making fully stable (100% stability index) emulsions, a 10-fold higher concentration of LaG than HaG in the emulsion aqueous phase was required. The difference in gellan concentration resulted in a bigger mean drop size, as well as lesser consistency coefficient and yield stress for HaG emulsion than LaG emulsion.Subsequently, the fully stable HaG and LaG emulsions were gelled by CaCl2 addition. LaG emulsion gel was self-supporting and had a dense microstructure (as observed by electron microscopy), whereas HaG emulsion gel was not self-supporting. Loading lipase into the emulsions before ionotropic gelation did not lead to unacceptable acid values for fish oil during the emulsion gels storage.When the lipase-loaded fish O/W emulsion gels were immersed in an acid solution which imitated the gastric fluid (yet without digestive enzymes) oil droplets flocculated (as observed by confocal microscopy). The acid immersion also increased the dynamic moduli of the gels. Lipase was not released into the surrounding acid solution from LaG emulsion gel. A subsequent immersion within an alkaline solution imitating the small intestine fluid (yet without digestive enzymes) reduced the dynamic moduli of both kinds of emulsion gels. The alkaline immersion also caused extensive crack propagation in LaG emulsion gel network, which was found associated with diminished value of tan δ (Gʹʹ/Gʹ) as an index of gel energy dissipation. Lipase was released form LaG emulsion gel into the alkaline solution, however, it took a remarkable period of time to begin.

Vasodilatory Effect of Alpinia officinarum Extract in Rat Mesenteric Arteries.

Background: Alpinia officinarum (A. officinarum) is known to exhibit a beneficial effect for anti-inflammatory, anti-oxidant, and anti-hyperlipidemic effects. However, no sufficient research data are available on the cardiovascular effect of A. officinarum. Thus, in this study, we investigate whether A. officinarum extract has direct effects on vascular reactivity. Methods: To examine whether A. officinarum extract affects vascular functionality, we measured isometric tension in rat mesenteric resistance arteries using a wire myograph. After arteries were pre-contracted with high-K+ (70 mM), phenylephrine (5 µM), or U46619 (1 µM), A. officinarum extract was treated. Results: A. officinarum extract induced vasodilation in a concentration-dependent manner, and this effect was endothelium independent. To further investigate the mechanism, we incubated arteries in a Ca2+-free and high-K+ solution, followed by the cumulative addition of CaCl2 (0.01–2.5 mM) with or without A. officinarum extract (30 µg/mL). Pre-treatment of A. officinarum extract reduced the contractile responses induced by cumulative administration of Ca2+, which suggests that extracellular Ca2+ influx was inhibited by the treatment of A. officinarum extract. These results were associated with a reduction in phosphorylated MLC20 in VSMCs treated with A. officinarum extract. Furthermore, eucalyptol, an active compound of A. officinarum extract, had a similar effect as A. officinarum extract, which causes vasodilation in mesenteric resistance arteries. Conclusion: A. officinarum extract and its active compound eucalyptol induce concentration-dependent vasodilation in mesenteric resistance arteries. These results suggest that administration of A. officinarum extract could exert beneficial effects to treat high blood pressure.

Dissociation mechanism of methane hydrate by CaCl2: an experimental and molecular dynamics study.

The formation of gas hydrate is a serious threat to the safe and effective completion of deepwater drilling and transportation operations, although it is considered as a potential energy resource. The inorganic salts are generally used as thermodynamic inhibitors; CaCl2 as a common additive in drilling fluids exhibits unique properties. In this study, we explored the dissociation mechanism of CH4 hydrate in CaCl2 solutions at the macroscopic and microscopic scale using experiment and molecular dynamics (MD) simulation. The experimental results showed that CaCl2 accelerated the dissociation rate of CH4 hydrate. The dissociation rate of CH4 hydrate increased with the increase of CaCl2 concentration at large depressurization pressure and was mainly affected by pressure when the depressurization pressure was lower. MD simulations were used to give an atomic scale interpretation of the macroscopic results obtained from the experiment. The results showed that the addition of CaCl2 destroyed the resistance liquid film formed during CH4 hydrate dissociation, thus accelerating the dissociation process, in good agreement with experimental results. HIGHLIGHTS: • The amount of CaCl2 affects CH4 hydrate dissociation at large depressurization pressure. • The dissociation of CH4 hydrate at low depressurization pressure is dependent on pressure. • Ca2+ destroys effectively the resistance liquid film produced during hydrate dissociation. • MD simulation results are in agreement with those of the experiment.

Effect of different types and concentrations of salts added toRequesoncheese on texture, sensory, and physiochemical characteristics

Different salts and concentrations (1% NaCl, 1.5% NaCl, 1% (1:1) NaCl/KCl, 1.5% (1:1) NaCl/KCl and 0.1% CaCl2) were used to elaborate Requeson cheese to evaluate yield, color, texture, physiochemical composition, and sensory characteristics. Yield, moisture, and protein content did not change among treatments (p>0.05). Fat content was higher (p<0.05) in the cheese without salt added. Adhesiveness was greater (p<0.05) in cheese with 0.1% CaCl2 and lowest in cheese without salt added. The a* value presented differences (p<0.05) among treatments. Cheese with 1.5% NaCl was the most accepted for its taste, followed by Requeson cheese with 1.5% NaCl/KC. In conclusion, the addition of CaCl2 to reduce sodium content in Requeson cheese is not recommended because change some characteristics of the cheese. However, the combination of NaCl/KCl at 1.5% could be used, since physicochemical, color, and texture characteristics were the same as the Requeson cheese with NaCl at 1.5%.

Compositional changes of casein micelles induced by calcium or chelatant addition at threefold and natural casein concentration

Milk protein concentrates are gaining importance in dairy products design and manufacture. The effect of adding CaCl2 or trisodium citrate (TSC) at various concentrations to micellar casein concentrate (MCC) with threefold concentrated casein micelles (CM) was assessed and compared with natural casein concentration. CM in MCC and in a skim milk-like system (MLC) were analysed regarding soluble and sedimentable casein, micellar calcium, phosphate, and micelle hydration. We hypothesised that casein micelles in MCC are less affected by these milieu changes. In fact, concentrated CM showed less pronounced compositional changes induced by TSC and CaCl2 addition. CM in MCC were less saturated in calcium and phosphate at higher levels of CaCl2 addition than in MLC. 94.2% of the CM remained intact up to 15 mm TSC addition, but only 41.5% CM in MLC. This study yields a wider understanding of CM if applied in concentrated form and provides options for modifying their functionalities.

Differential Response to NaCl Osmotic Stress in Sequentially Harvested Hydroponic Red and Green Basil and the Role of Calcium.

Basil (Ocimum basilicum L.) is a heterogeneous reservoir of bioactive compounds that provide recognized benefits to human health, rendering it a model aromatic herb. Notwithstanding the application of nutritional stress, such as sodium chloride (NaCl) salinity, which mainly affects the primary metabolism, it also triggers adaptive mechanisms that involve the production of bioactive secondary metabolites. Genotype selection and the exogenous application of calcium chloride (CaCl2) help minimize salinity’s suppressive effects on growth. In the present study, we hypothesize that the ratio of different salt types may induce differential responses in the function of preharvest factors in hydroponic basil culture. In this perspective, the stock nutrient solution (Control) was supplemented with 12.5 mm NaCl + 8.33 mm CaCl2 (Moderate Mix), 25 mm NaCl (Moderate NaCl), 25 mm NaCl + 16.66 of CaCl2 (High Mix), or 50 mM of NaCl (High NaCl) with the objective of evaluating the different impact of salinity on yield, sensory quality (color and aroma profile), and the accumulation of minerals and bioactive compounds in two successive harvests of green and red basil cultivars. Although more productive (+39.0% fresh weight) than the red one, the green cultivar exhibited higher susceptibility to salinity, especially under the High Mix and High NaCl treatments. The addition of CaCl2 to the High Mix solution reduced the sodium by 70.4% and increased the total polyphenols by 21.5% compared to the equivalent isomolar solution (High NaCl). The crop performance in terms of fresh and dry yield improved for both cultivars at the second cut. Regardless of cultivar and salt treatment, successive harvests also increased the concentration of phenols and vitamin C (29.7 and 61.5%, respectively) while reducing (−6.9%) eucalyptol, the most abundant aromatic compound in both cultivars. Salinity, as well as the mechanical stress induced by cutting, improved the functional quality of basil. However, the productive responses to the conditions imposed in our work once again highlighted the importance of genetic background. Specifically, CaCl2 in the Moderate Mix solution preserved fresh leaf weight in the most stress-sensitive green cultivar.

Investigation of the adsorption behavior of Pb(II) onto natural-aged microplastics as affected by salt ions

In this study, the adsorption behavior of Pb(II) on natural-aged and virgin microplastics in different electrolyte solutions was investigated. The results demonstrated that natural-aged microplastics exhibited higher adsorption capacity for Pb(II) compared to virgin ones, and the addition of CaCl2 strongly inhibited the adsorption amount of Pb(II). The adsorption kinetics of Pb(II) adsorption were better fitted by the pseudo-second order model and Elovich equation, and were slowed down greatly at higher ionic strength. The rate-limiting steps of adsorption process were dominated by intra-particle diffusion. The adsorption isotherm of Pb(II) onto microplastics affected by salt ions can be well described by Freundlich model, the greater adsorption efficiency of natural-aged microplastics proved that adsorption process was multilayer and heterogeneous. In addition, pH significantly influenced the adsorption of Pb(II) due to the changes electrostatic interactions. The effect of fulvic acid in the electrolyte solutions was also revealed and attributed to the complexation with Na+ and Ca2+. Furthermore, the higher pH and ionic strength in different environmental water dramatically decreased adsorption capacity onto microplastics. Finally, it’s confirmed that the adsorption mechanisms affected by salt ions mainly involve electrostatic interaction, surface complexation, and ionic exchange. These findings indicate that salt ions exert an important influence on the adsorption of heavy metals for MPs, which should be further concerned.

Effects of different calcium salts on the physicochemical properties of sliver carp myosin

To investigate the effects of different calcium salts on the physicochemical properties of myosin, the intermolecular interactions, particle size, surface hydrophobicity, reactive sulfhydryl group content and rheological properties of sliver carp myosin with the addition of four different kinds of calcium salts (CaCl2, calcium citrate (CC), nano-hydroxyapatite (HAP), tricalcium phosphate (TCP)) during gel processing were measured. The results showed that the addition of CaCl2 promoted the unwinding of α-helix, the increase in hydrophobic interactions, the formation of disulfide bonds of myosin, and increased the viscoelasticity of myosin. While, the addition of calcium citrate (CC) enhanced the hydrophobic interaction between myosin molecules, and the viscoelasticity of CC-added myosin was second only to the CaCl2-added myosin. On the contrary, the addition of HAP and TCP interfered with the hydrophobic interaction between myosin molecules, and greatly reduced the viscoelasticity of myosin. In summary, calcium with high calcium release rate can improve the physicochemical properties of myosin, HAP and TCP with a very low calcium release rate interfered with the formation of myosin gelation. And it could be concluded that the calcium ions played a leading role in the physicochemical properties of myosin, the more calcium ion that the calcium salt can release, the better physicochemical properties the myosin were. Our work may provide an insight into the phenomenon why different kinds of calcium salts differ from each other on affecting the physicochemical properties of myosin during gel processing.