Sodium Chloride Concentration Research Articles

SNP alleviates ferric and salt stress in Phaseolus vulgaris seeds

Seed germination and early development are delicate events often influenced by various environmental factors. Among these factors, the accumulation of salts and heavy metals in the soil is noteworthy. This study aimed to observe the effect of priming with solutions of sodium nitroprusside, polyethylene glycol 6000, and potassium nitrate on the germination of Phaseolus vulgaris seeds exposed to toxic conditions of iron and sodium chloride. Seeds were germinated on plates placed in a growth chamber at a constant temperature of 25°C and a 12-hour photoperiod. The percentage of germination, germination speed, root and shoot lengths, catalase, peroxidase activities, and malondialdehyde content were evaluated. Exposure to high concentrations of sodium chloride and iron reduced germination percentage, germination speed, root and shoot lengths of treated plants. Only sodium nitroprusside treatment mitigated the effects of stressors. No increase in malondialdehyde content was observed in any treatment, suggesting no lipid peroxidation of membranes. However, all treatments showed increased catalase activity, possibly indicating oxidative stress and metabolic damage. Sodium nitroprusside stands out as a stress alleviator for sodium chloride and iron accumulation during the germination phase.

Structural and electrical characterization of cadmium phosphate glasses doped with different concentration of sodium chloride

Structural and electrical characterization of cadmium phosphate glasses doped with different concentration of sodium chloride

Influencing Factors on the Wet Impregnation of Additive‐Manufactured Catalyst Support Structures

AbstractThe wet impregnation of additive manufactured aluminum oxide cylinders with platinum is investigated. The influence of five parameters on the penetration depth and the platinum loading is evaluated. A smaller penetration depth is obtained by increasing pH, sodium chloride concentration in the impregnation solution, decreasing impregnation solution volume, heating rate during subsequent calcination, and no vacuum during prewetting before the impregnation. A pH range of 2 to 4, a low chloride concentration, a small liquid volume, and no vacuum drawing lead to high platinum uptake. This investigation is crucial in understanding and optimizing the wet impregnation process, providing practical guidance for future research with more complex structures.

OPTIMIZATION OF LIQUIDSOAP FORMULATION

The quality of liquid soap for washing hands depends on its chemical composition, and it is evaluated by the physicochemical and functional characteristics of that product. The aim of the work is to prepare different series of liquid soap formulations by varying the concentrations of anionic and amphoteric surfactantsand sodium chloride, and to optimize the formulation. The effects of the optimization were evaluated based on the results of the analysis of the physico-chemical parameters of the prepared formulations, such as density, viscosity, surface tension and critical concentration of micelles. As amphoteric and anionic surfactant concentrations in liquid soap increase, density and viscosity values increase. The value of the surface tension decreases with the increase in the concentration of the surfactants present, with the amphoteric surfactant making a greater contribution to the decrease. Regardless of certain advantages that the anionic surfactant shows in relation to the amphoteric one, the best characteristics of the liquid soap are shown by the formulation thatcontains a combination of both used surfactants. The addition of NaCl to the liquid soap formulation has multiple significance, but also a different effect on the physical and chemical characteristics at lower and higher concentrations. Functional and some physico-chemical characteristics of liquid hand washing soap depend on the pH value of the formulation. As the pH value increases, the surface tension and CMC increase to certain values, so pH=5.5 is taken as the optimal pH value of liquid soap, as a compromise between the values of the measured characteristics and the pH value of human skin. This research showed that the formulation containing 5.4w/w%anionic surfactant, 1w/w%amphoteric surfactant and 4w/w% NaCl represents the optimal liquid soap formulation. KEYWORDS:liquid soap; content of liquid soap; surfactants; electrolyte in liquid soap; characteristics of liquid soap; optimization of formulation

Effect of environmental factors on seed germination and seedling emergence of weedy rice (Oryza sativa f. spontanea) in China

Abstract Weedy rice (Oryza sativa f. spontanea Auct. ex Backer) is a troublesome annual weed from the Gramineae family and infests rice (Oryza sativa L.) fields globally, with a notable presence in China. However, limited information is available regarding the effects of diverse environmental factors on its germination and emergence. A better understanding of the seed biology and ecology of weedy rice is crucial for developing effective weed management strategies. Experiments were conducted to evaluate the effects of temperature, light, soil burial depth, wheat (Triticum aestivum L.) crop residue amount, salt stress, osmotic stress, and radiant heat on the germination and seedling emergence of weedy rice. Weedy rice exhibited robust germination (>98%) when exposed to varying day/night temperatures (20/15 to 35/30 C) and remained unaffected by light conditions. Seedling emergence was not influenced within the top 5-cm soil layer, where 100% of the seedlings emerged. However, emergence decreased as the soil burial depth increased, eventually resulting in no emergence from a burial depth of 11 cm. The soil burial depth required for 50% of the maximum emergence was 8.3 cm. Seedling emergence ranged from 97% to 100% across different amounts of the wheat straw residue cover (0 to 10,000 kg ha−1). The sodium chloride concentration and osmotic potential required for 50% were 230.8 mM and −0.5 MPa, respectively. No germination was observed when weedy rice seeds were exposed to >110 C pretreatment (radiant heat for 5 min), indicating that residue burning could reduce infestation of weedy rice. The insights gained from this study contribute valuable knowledge to enhance the integrated management of weedy rice in China.

Morpho-physiological traits and stress indices reveal divergence in early-stage salt stress response in elite soybean germplasm

This study assessed the salt stress response of seventy soybean genotypes by exposing seedlings to sodium chloride (NaCl) concentrations of 0, 75, 100, and 125 mM. Salinity stress significantly reduced root length, shoot length, fresh and dry root/shoot weight, and root/shoot ratio. A total of 62 genotypes germinated at 125 mM, showing significant phenotypic variation in traits such as root length, shoot length, fresh shoot weight, and dry shoot weight. Pearson’s correlation analysis revealed a strong positive correlation between most morpho-physiological traits, suggesting their interdependence. Eight salinity tolerance indices i.e., Fresh Weight Stress Tolerance Index (FWSI), Dry Weight Stress Tolerance Index (DWSI), Root Length Salinity Index (RLSI), Shoot Length Salinity Index (SLSI), Salinity Tolerance Index (STI), Salinity Susceptibility Index (SSI), Tolerance Index (TI), and Percent Reduction (PR) were calculated to assess genotypes response. Na+ concentration and antioxidant activities significantly increased under salt stress compared to the control. The activities of antioxidant enzymes, as well as the levels of reactive oxygen species (ROS) such as H2O2 and O2−, were markedly higher under salt stress compared to the control. Hierarchical cluster analysis grouped genotypes into six clusters, with clusters V and VI comprising genotypes exhibiting higher salt tolerance based on high FWSI, DWSI, and STI values, and low PR, SSI, and TI values. Eight salinity tolerance indices, including Fresh Weight Stress Tolerance Index (FWSI), Dry Weight Stress Tolerance Index (DWSI), Root Length Salinity Index (RLSI), and Salinity Tolerance Index (STI), were used to evaluate the genotypes’ responses. The study revealed that the average FWSI value for all genotypes under treatments was 54.20 ± 12.93. The highest FWSI was recorded for the genotype Black (92.52), followed by NIBGE-224 (84.70) and NIBGE-183 (81.05). In contrast, Malakand-96 had the lowest FWSI (28.49), followed by SPS-10 (32.74) and SPS-08 (34.55). PGRA-91 had the highest STI (0.83), followed by SPS-9 (0.75) and NIBGE-115 (0.72), while NIBGE-335, SPS-24, and Malakand-96 had the lowest STI values. Positive correlations were observed between root length and shoot length (0.69**), shoot length and fresh shoot weight (0.63**), and other related traits. Overall, this study identified promising soybean genotypes with varying degrees of salt tolerance. These findings can be utilized in breeding programs to develop salt-tolerant soybean varieties for salinity-affected agricultural lands.

Understanding lipid oxidation in dried meat and cured dried meat: Insights from peroxide index analysis

The lipid oxidation process is one of the main food spoilage reactions, resulting in the appearance of unpleasant flavors and odors, known as rancidity. This study aimed to evaluate the lipid oxidation activity through the peroxide index, together with some chemical and biochemical constituents, of meat products with a high sodium content that underwent salting process and were sold to consumers. Samples of dried meat/charqui (CA: n = 22 and CB: n = 22) and jerked beef (JBA: n = 27 and JBB: n = 27) were analyzed. The peroxide index, rancidity test, formaldehyde test, sodium chloride, sodium, nitrite, proximate composition, and calories were analyzed. The main results demonstrated a high peroxide index and nitrite concentrations in jerked beef samples (JBA and JBB). The high concentrations of moisture and nitrite probably increased lipid oxidation in jerked beef samples, and lipid oxidation activity was inhibited by high concentrations of sodium chloride in dried meat samples.

Selection of the optimal formulation of the biopolymer system for the stimulation of productive formations

The object of study in this paper is the biopolymer system «X» – a complex composition that includes a biopolymer, salts and a thermal stabiliser intended for use in drilling fluids at high temperatures. The components of the formulation include complex reagent «X» for regulating structural, mechanical, rheological and filtration properties, as well as inhibitors (sodium and potassium chloride) and filler. Components of the biopolymer system (sodium chloride, organo-mineral colmatant thermal stabiliser) increase its thermal stability. One of the most problematic areas is the mechanism of sodium chloride's thermal stabilising effect. It is associated with an increase in the overall mineralisation of the drilling mud, which leads to a certain conformation of biopolymer molecules, accelerates gelation processes and counteracts the temperature dilution of the system. The results obtained can be explained as follows: – an increase in the concentration of sodium chloride leads to an increase in the ionic strength of the solution, which contributes to a change in the conformation of biopolymer molecules, enhancing intermolecular interactions and, as a result, increasing the viscosity and stability of the system; – the organo-mineral colmatant heat stabiliser promotes the formation of a filtration crust on the well walls, which prevents fluid loss and reduces rock permeability; – all components of the system interact with each other, affecting the properties of the solution. The optimum ratio of components allows achieving the required rheological characteristics and ensuring the stability of the system at high temperatures. As a result of processing the information on technologies for tapping productive horizons, the disadvantages and advantages of each of them were noted. The existing drilling fluid systems used to tap productive horizons at high temperatures were considered. However, more attention was paid to the selection of a new optimal formulation of the biopolymer system, in accordance with the specified rheological and structural and mechanical properties for further implementation in practice. This ensures the possibility of obtaining predictive parameters of the drilling mud. The proposed system has a number of advantages over similar ones, namely: – the system retains its properties at high temperatures; – the system provides the required values of viscosity, filtration and static shear stress; – due to the use of an optimal formulation, high efficiency is achieved at a relatively low cost.

Production Physiology and Biochemical properties of Crude Thermophile Protease by Mild - Halophilic Bacillus thuringiensis aizawai HD 865

Objective: The current study aims to enrich the research library of Bacillus thuringensis, the most famous bacteria as a biopesticide, with a product that may enhance its ability as a biopesticide as well as its many other applications, namely the heat-tolerant alkaline protease. Methods: The strain Bacillus thuringiensis aizawai HD 865, obtained from HD Culture Collection was grown on a liquid growth medium of nutrient broth and yeast extract, and colonies were counted on agar plates. The zygote is then transferred to a skim milk environment to estimate the enzymatic activity under the different growth conditions of the growth environment (sodium chloride concentration, pH, aeration, fermentation duration), then testing the optimal conditions for enzymatic activity in the enzymatic reaction mixture (sodium chloride concentration, salinity resistance, optimum temperature, thermal stability, optimum pH and stability). Then analyze the data statistically. Results: Optimum alkaline protease medium production conditions were, 2 % NaCl, so Bacillus thuringiensis aizawai HD865 a mild - halophilic microorganism, aeration level 80%, pH 7 and 8 days of fermentation period. On the other hand, crude alkaline protease properties were found that, the optimum temperature for its activity was relatively high (70ºC), while heat-stabilities after 5 min of heating crude enzyme in boiling water bath then incubated for 15min on 30, 40, 50, 60, 70ºC, were 184.23, 178.07, 164.29, 165.51 and 121.46 Units, respectively; whereas the optimum pH was at pH 7.6 (151.76 Units) with tris buffer then at pH 9.6 with glycine - NaOH buffer; While pH stability was at pH 7.6 with tris buffer then at pH 8.4 with glycine - NaOH buffer. Thus, activities have decreased at different concentrations (0, 1, 2, 3, 4, 5 %) of sodium chloride in reaction mixture with enzyme activities (151.25, 137.35, 135.12, 135, 135.89, 114.38 Units) respectively, also decreased when rinse crude enzyme for 5 min in NaCl (0, 1, 2, 3, 4, 5 %), with (151.04, 175.57, 168.69, 154.61, 155.39 and 143.39 Units) respectively. Conclusion: Bacillus thuringiensis aizawai HD 865 strain is considered a low - salt tolerant strain, while the alkaline protease extracted from it is heat - resistant.

Chrysin alleviates salt stress in tomato by physiological, biochemical, and genetic mechanisms

Soil salinity greatly reduces agricultural productivity, especially in dry and semi-arid regions, by interfering with physiological and biochemical processes. This research aimed to determine whether Chrysin (Chr) can mitigate the negative effects of salinity on growth parameters, antioxidant enzyme activity, and gene expression in tomato (Solanum lycopersicum L.) plants. Experiments were conducted in a semi-controlled greenhouse, with plants subjected to varying concentrations of sodium chloride (NaCl) (0 and 100 mM) and Chr (0, 0.1, 0.5, and 1.0 mM). Results revealed that salinity stress significantly reduced plant height, leaf area, and chlorophyll content while increasing hydrogen peroxide (H2O2), malondialdehyde (MDA), and proline levels, indicating oxidative stress. Chr application alleviated these detrimental effects by enhancing the activity of antioxidant enzymes such as catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD), thereby reducing reactive oxygen species (ROS) accumulation. Additionally, Chr treatments improved plant water status and mineral content under salt stress. Gene expression analysis showed that Chr positively regulated the transcription of salt tolerance-related genes, including HKT1-1, HKT1-2, and PIP1-2, which are associated with sodium ion transport and water balance. These findings suggest that Chr can be an effective biostimulant for enhancing salt tolerance in tomato plants by modulating physiological, biochemical, and genetic mechanisms. This study provides insights into Chr's potential as a sustainable solution for improving crop resilience to salinity in agricultural practices. Further research is recommended to optimize Chr concentrations for maximum efficacy.

Capsicum annuum NAC4 (CaNAC4) Is a Transcription Factor with Roles in Biotic and Abiotic Stresses.

Transcription factors (TFs) regulate gene expression by binding to DNA. The NAC gene family in plants consists of crucial TFs that influence plant development and stress responses. The whole genome of Capsicum annuum shows over 100 NAC genes (CaNAC). Functional characteristics of the most CaNAC TFs are unknown. In this study, we identified CaNAC4, a novel NAC TF in C. annuum. CaNAC4 expression increased after inoculation with the pathogens, Xanthomonas axonopodis pv. vesicatoria race 3 and X. axonopodis pv. glycines 8ra, and following treatment with the plant hormones, salicylic acid and abscisic acid. We investigated the functional characteristics of the CaNAC4 gene and its roles in salt tolerance and anti-pathogen defense in transgenic Nicotiana benthamiana. For salt stress analysis, the leaf discs of wild-type and CaNAC4-transgenic N. benthamiana plants were exposed to different concentrations of sodium chloride. Chlorophyll loss was more severe in salt stress-treated wild-type plants than in CaNAC4-transgenic plants. To analyze the role of CaNAC4 in anti-pathogen defense, a spore suspension of Botrytis cinerea was used to infect the leaves. The disease caused by B. cinerea gradually increased in severity, and the symptoms were clearer in the CaNAC4-transgenic lines. We also investigated hypersensitive response (HR) in CaNAC4-transgenic plants. The results showed a stronger HR in wild-type plants after infiltration with the apoptosis regulator, BAX. In conclusion, our results suggest that CaNAC4 may enhance salt tolerance and act as a negative regulator of biotic stress in plants.

Effect of Temperature and Salinity on Survival of Protoscoleces of Hydatid Cyst in Liver In Vitro.

Hydatid cyst is the metacestode stage of Echinococcus granulosus that occurs in herbivores and humans as intermediate hosts by consuming parasite eggs through forage and vegetables. Carnivores, as definitive hosts, become infected by consuming infected vesicles of herbivores. The most effective treatment for a hydatid cyst is surgical operation. Inactivating E. granulosus protoscoleces through heating, cooling, or chemicals such as sodium chloride can be considered an effective method for controlling hydatidosis in both humans and animals. The main objective of this study was to evaluate the effect of different temperatures and salinity conditions on the survival of Echinococcus granulosus protoscoleces. For this purpose, 50 g of infected liver (in triplicate) was separately treated with different temperatures (+10°C, +50°C, +60°C, +72°C, and -20°C) and concentrations of sodium chloride (5%, 10%, 15%, and 20%) for 3, 6, 12, 24, 48, and 72 h. Additionally, 50 g of infected liver was stored separately in the refrigerator (+4°C) as a control group. The survival rate of the protoscoleces was evaluated by staining with 1% eosin under a light microscope. The results showed that the protoscoleces were significantly affected, with 100% mortality at -20°C after 0.5 h, and complete death at +72°C, +60°C, +50°C, and +10°C after 1, 1.5, 3, and 24 h, respectively (p < 0.005). Similarly, the protoscoleces in the liver mass survived at 5% NaCl after 3 h but died at 10% after 24 h, at 15% after 12 h, and at 20% after 6 h. It is concluded that exposing the liver infected with protoscoleces hydatid cyst to a temperature of -20°C and a sodium chloride concentration of 10% for 24 h is suitable for inactivating the protoscoleces.

Monoammonium Glutamate: What Is Its Potential in the Reduction of Sodium Content in Different Food Matrices?

ABSTRACTThe objective of the study was to assess the efficacy of monoammonium glutamate (MAG) in reducing the sodium chloride (NaCl) content (CCRD) of food matrices, including shoestring potatoes, requeijão cheese, and beef burgers. To this end, a time intensity (TI) analysis, temporal dominance of sensations (TDSs), and acceptance tests were employed to evaluate the NaCl reduction in various food items. The TI analysis showed that all experimental units had a mean salty taste intensity that equaled or exceeded the control. The TDS profiles of shoestring potatoes and requeijão cheese and the control were similar. However, the requeijão cheese exhibited significantly lower acceptance than the controls. The food matrices influenced the potential use of MAG and the CCRD. The addition of 2% MAG to the formulation reduced the NaCl content by up to 50% in shoestring potatoes and 65% in beef burgers without compromising the temporal perception of a salty taste and sensory acceptance.

Ion Correlations Decrease Particle Aggregation Rate by Increasing Hydration Forces at Interfaces.

The connection between solution structure, particle forces, and emergent phenomena at solid-liquid interfaces remains ambiguous. In this case study on boehmite aggregation, we established a connection between interfacial solution structure, emerging hydration forces between two approaching particles, and the resulting structure and kinetics of particle aggregation. In contrast to expectations from continuum-based theories, we observed a nonmonotonic dependence of the aggregation rate on the concentration of sodium chloride, nitrate, or nitrite, decreasing by 15-fold in 4 molal compared to 1 molal solutions. These results are accompanied by an increase in repulsive hydration forces and interfacial oscillatory features from 0.27-0.31 nm in 0.01 molal to 0.38-0.52 nm in 2 molal. Moreover, molecular dynamics (MD) simulations indicated that these changes correspond to enhanced ion correlations near the interface and produced loosely bound aggregates that retain electrolyte between the particles. We anticipate that these results will enable the prediction of particle aggregation, attachment, and assembly, with broad relevance to interfacial phenomena.

In Vitro evaluation of probiotic properties of lactic acid bacteria strains isolated from juçara fruit native to the Atlantic Forest

Lactic acid bacteria (LAB) are the microorganisms most commonly used as probiotics. Since probiotic benefits are strain-dependent, there is a continuous need for research into new cultures with probiotic properties. Fruits such as juçara (Euterpe edulis Martius), a palm species from the Atlantic Forest threatened with extinction, are rich niches for microorganisms, including LAB. This study investigated the probiotic properties of Lactococcus lactis J7 and Leuconostoc pseudomesenteroides JF17 strains isolated from juçara fruits native to the Atlantic Forest. Probiotic characteristics, such as tolerance to simulated gastrointestinal fluids or juices, hydrophobicity, autoaggregation, coaggregation properties, inhibition of pathogenic microorganisms, and technological properties were evaluated. The survival rate of L. lactis J7 and L. pseudomesenteroides JF17 decreased after exposure to simulated gastrointestinal conditions; however, L. lactis J7 was more resistant, maintaining viability at the end of the enteric phase of 6.07 ± 0.16 log CFU mL-1. The J7 strain also exhibited the highest values in hydrophobicity (12.55 ± 0.52%), autoaggregation (25.63 ± 0.75%), and coaggregation capacity with E. coli ATCC 25922 (21.52 ± 0.98%) and S. Enteritidis ATCC 13076 (22.68 ± 1.01%). Both J7 and JF17 strains demonstrated antimicrobial activity, confirmed by the multilayer agar plate system. Additionally, the growth of the strains was temperature-dependent, and they were able to thrive in high concentrations of sodium chloride (6%). Thus, L. lactis J7 is a promising probiotic candidate for the development of functional products. Nevertheless, further studies using animal models are necessary to explore the properties of these probiotic bacteria. Novel strains isolated from fruits should be studied to broaden the application of probiotic microorganisms in the development of foods and medicines.

Facile Determination of Aluminum Content in Industrial Brine by Investigating the Effects of Buffer Systems.

The aluminum content of concentrated (27 wt%) sodium chloride solutions could be crucial for large-scale chlor-alkali-based industries applying membrane cell electrolysis. Thus, a facile method which enables a fast and reliable protocol to determine the Al content of these solutions on ppb scale in industrial environments is fundamentally important. It was demonstrated that the increased sensitivity of colorful Al-ECR (eriochrome cyanine R) complex by the use of a cationic surfactant and specific biological buffers could effectively indicate the Al content in an extended pH interval of a concentrated saline medium under industrial conditions. The dependence of the analytical protocol on pH, temperature, time, wavelength, and the salinity of the medium was investigated. It was shown that the absorbance-based measurements of the solution should be performed at least 2-4 h after its preparation. By applying the selected two Good's buffers (HEPES: 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, MOPS: 3-(N-morpholino)-propanesulfonic acid) and Tris (tris(hydroxymethyl)aminomethane), 32.8-38.1 % increase in the sensitivity was achieved for saturated NaCl solutions. Moreover, the limits of detection and quantification (LOD, LOQ) were also lowered by 19.0-29.8 %, and the salinity dependence of the calibration was also reduced.

Cascaded Dual-Tapered Optical Microfiber Sensors for Simultaneous Detection of Refractive Indices in Multiple Solutions

ABSTRACT A cascaded single-mode tapered fiber (SMTF) has been investigated for simultaneous detection of two refractive indices (RI). Two SMTFs with distinct-free spectral range (FSR) of 3.88 nm and 23.23 nm were concatenated to realize the cascaded SMTF. The interaction between evanescent waves generated by the cascaded SMTF and variations in the surrounding environment results in measurable wavelength shifts. When tested with different concentrations of sodium chloride to simulate RI variations, wavelength shifts were yielded with FSR corresponding to the stimulated SMTF. This work validates the feasibility of using cascaded SMTFs for simultaneous dual RI detection in real-world applications.

Effect of inorganic salt impurities on seeded precipitation of silica hydrate from sodium silicate solution

To clarify the precipitation of silica hydrate from the real desilication solutions of aluminosilicate solid wastes by adding seeds and improve integrated waste utilization, the seeded precipitation was studied using synthesized sodium silicate solution containing different inorganic salt impurities. The results show that sodium chloride, sodium sulfate, sodium carbonate, or calcium chloride can change the siloxy group structure. The number of high-polymeric siloxy groups decreases with increasing sodium chloride or sodium sulfate concentration, which is detrimental to seeded precipitation. Calcium chloride favors the polymerization of silicate ions, and even the chain groups precipitate with the precipitation of high-polymeric sheet and cage-like siloxy groups. The introduced sodium cations in sodium carbonate render a more open network structure of high-polymeric siloxy groups, although the carbonate ions favor the polymerization of siloxy groups. No matter how the four impurities affect the siloxy group structure, the precipitates are always amorphous opal-A silica hydrate.

Insights into the Structural and Thermal Properties of Pepsin-Soluble Collagen from Daggertooth pike conger (Muraenesox cinereus)

Pepsin soluble collagen (PSC) is a type-1 collagen which is abundant in skin. The pepsin soluble collagen was successfully extracted from the skin of Daggertooth pike conger (Muraenesox cinereus) by using the conventional method of salt precipitation followed by dialysis. Pepsin-soluble collagen showed a yield of 10.12% on wet matter basis and 25.5% on dry matter basis. The triple helical structure of collagen was confirmed by Fourier Transform Infrared Spectroscopy (FTIR) and UV-Visible spectrophotometry. Isolated PSC was confirmed as type 1 collagen by Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE). FTIR spectra of PSC suggested that the secondary structure of the triple helical collagen was intact even after pepsin digestion. Pepsin-soluble collagen was soluble in acidic pH with maximum solubility at pH 4. The solubility was found to be decreased with an increase in the concentration of sodium chloride with a minimum solubility at 4%. The present PSC isolate from eel fish exhibited comparatively high thermal stability of 36 ͦ C. Morphological analysis by Scanning electron microscopy (SEM) revealed a porous structure and comparatively high thermal stability makes it a promising biomaterial.

Effect of salt stress on growth and phenolic compounds production in callus suspension culture of the dioecious species thyrse sorrel (Rumex thyrsiflorus Fingerh.)

The sex-dependent differences in the response to salt stress of the dioecious Rumex thyrsiflorus and the influence of different concentrations of sodium chloride (NaCl) on the biosynthesis of phenolic compounds in callus suspension cultures were evaluated. The cultures originated from callus obtained on hypocotyls isolated from male and female seedlings were cultured on Murashige and Skoog medium supplemented with 0.4 mg/L 6-benzylaminopurine and 1 mg/L 2,4-dichlorophenoxyacetic acid. The results showed that the response to salt stress depends on both the sex of the plant and the NaCl concentration in the culture medium. The analysis of the main morphometric parameters showed that callus tissue derived from the hypocotyls of female seedlings was less sensitive to salt stress than that from male seedlings, which was correlated with higher concentrations of phenolic compounds. The optimal NaCl concentration to increase the production of phenolic compounds was 129 mM for females and 43 mM for males. In the methanolic tissue extracts 22 compounds were determined using the HPLC–DAD method. In general, higher amounts of compounds were detected in the extracts from the female tissue. The following dominated: catechin (max. 213.31), cryptochlorogenic acid (max. 76.35) and epicatechin (max. 54.84) (mg/100 g DW). This comprehensive phytochemical analysis of the sex-related aspects of the response to salt stress was performed for the first time in this dioecious model species. The results revealed potential application of NaCl as the ecological friendly and inexpensive elicitor to increase the production of pharmaceutically valuable compounds and highlight the importance of dioecy in phytochemistry.