scholarly journals Effects of Sodium Chloride on Algae and Crustaceans—The Neighbouring Links of the Water Trophic Chain

Water ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 2493
Author(s):  
Łukasz Sikorski

Salinity limits the habitable living environment for aquatic organisms. Algae and crustaceans are widely used as bioindicators in freshwater environmental risk assessments. This study aimed to use biotests (Algaltoxkit and Daphtoxkit) to determine the effect of sodium chloride (NaCl) on algae Pseudokirchneriella subcapitata and crustaceans Daphnia magna. Standard biotests were extended to include NaCl effects on algal chlorophyll fluorescence and crustaceans swimming and heart rate. It was found that after 7 days, a 0.24 M of NaCl reduced the growth rate of the algae by 50% (EC50). A NaCl of 0.27 M inhibited the minimum (Fo), maximum (Fm) and variable (Fv) fluorescence by 50%, on average. The crustaceans also responded to NaCl. Those exposed to 0.19 M NaCl during 15 min swam slower by 50% and a 0.27 M immobilised three organisms (EC50). The crustacean immobilisation was less modified by NaCl than swimming. To determine the lethal effect in non-swimming organisms, the heart rate was examined. At 0.35 M of NaCl, all organisms were dead after 30 min, as their hearts did not beat. These studies suggest that physiological and behavioural features are sensitive indicators of the toxic effects of NaCl in algae and crustaceans, before morphological changes are observed.

2014 ◽  
Vol 77 (10) ◽  
pp. 1696-1702 ◽  
Author(s):  
VIJAY K. JUNEJA ◽  
JIMENA GARCIA-DÁVILA ◽  
JULIO CESAR LOPEZ-ROMERO ◽  
ETNA AIDA PENA-RAMOS ◽  
JUAN PEDRO CAMOU ◽  
...  

The interactive effects of heating temperature (55 to 65°C), sodium chloride (NaCl; 0 to 2%), and green tea 60% polyphenol extract (GTPE; 0 to 3%) on the heat resistance of a five-strain mixture of Listeria monocytogenes in ground turkey were determined. Thermal death times were quantified in bags that were submerged in a circulating water bath set at 55, 57, 60, 63, and 65°C. The recovery medium was tryptic soy agar supplemented with 0.6% yeast extract and 1% sodium pyruvate. D-values were analyzed by second-order response surface regression for temperature, NaCl, and GTPE. The data indicated that all three factors interacted to affect the inactivation of the pathogen. The D-values for turkey with no NaCl or GTPE at 55, 57, 60, 63, and 65°C were 36.3, 20.8, 13.2, 4.1, and 2.9 min, respectively. Although NaCl exhibited a concentration-dependent protective effect against heat lethality on L. monocytogenes in turkey, addition of GTPE rendered the pathogen more sensitive to the lethal effect of heat. GTPE levels up to 1.5% interacted with NaCl and reduced the protective effect of NaCl on heat resistance of the pathogen. Food processors can use the predictive model to design an appropriate heat treatment that would inactivate L. monocytogenes in cooked turkey products without adversely affecting the quality of the product.


1960 ◽  
Vol 6 (5) ◽  
pp. 535-543 ◽  
Author(s):  
Dinah Abram ◽  
N. E. Gibbons

The optical densities of suspensions of cells of Halobacterium cutirubrum, H. halobium, or H. salinarium, grown in media containing 4.5 M sodium chloride, increase as the salt concentration of the suspending medium decreases, until a maximum is reached at about 2 M; below this concentration there is an abrupt decrease in optical density. The cells are rod shaped in 4.5 M salt and change, as the salt concentration decreases, through irregular transition forms to spheres; equal numbers of transition forms and spheres are present at the point of maximum turbidity, while spheres predominate at lower salt concentrations. Cells suspended in 3.0 M salt, although slightly swollen, are viable, but viability decreases rapidly with the more drastic changes in morphology at lower salt concentrations. Cells grown in the presence of iron are more resistant to morphological changes but follow the same sequence. Cells "fixed" with formaldehyde, at any point in the sequence, act as osmometers and do not rupture in distilled water although their volume increases 10–14 times. The results indicate that the red halophilic rods require a high sodium chloride content in their growth or suspending medium to maintain a rigid cell wall structure.


2005 ◽  
Vol 62 (1) ◽  
pp. 17-25 ◽  
Author(s):  
Nathalie Chèvre ◽  
Alessandra R. Brazzale ◽  
Kristin Becker-van Slooten ◽  
Renata Behra ◽  
Joseph Tarradellas ◽  
...  

2012 ◽  
Vol 72 (2) ◽  
pp. 343-351 ◽  
Author(s):  
MC. Bittencourt-Oliveira ◽  
B. Buch ◽  
TC. Hereman ◽  
JDT. Arruda-Neto ◽  
AN. Moura ◽  
...  

Cylindrospermopsis raciborskii (Woloszynska) Seenayya et Subba Raju (Ordem Nostocales) is one of the most troublesome bloom-forming species in Brazil. Understanding the population dynamics of the different morphotypes of C. raciborskii (straight and coiled) could assist in the prediction of favourable conditions for the proliferation of this potentially toxin-producing species. The aim of the present study was to assess the effects of two different light intensities and temperatures on the growth rate and morphology of the trichomes of the straight and coiled morphotypes. For such, two non-toxin producing strains of C. raciborskii were used - one with a coiled trichome (ITEP31) and another with a straight trichome (ITEP28). The strains were cultured in BG-11 medium in a climatic chamber under controlled conditions. Two light intensities (30 and 90 µmol.m-2.s-1 ) were combined at temperatures of 21 and 31 °C and the growth rate and morphological changes were analysed. The morphotypes responded differently to the different temperatures and light intensities. Both strains exhibited faster growth velocities when submitted to higher light intensity and temperature. The lower temperature and higher luminosity hampered the development of both strains. Variations in cellular morphology and an absence of akinetes in both strains were related to the lower temperature (21 °C). The coiled morphotype demonstrated considerable phenotype plasticity, changing the morphology of trichome throughout its growth curve. Although molecular analysis does not sustain the separation of the morphotypes as distinct species, their different eco-physiological responses should be considered further knowledge of extreme importance for the population control of these potentially toxic organisms.


2004 ◽  
Vol 70 (5) ◽  
pp. 2928-2934 ◽  
Author(s):  
Maria Lövenklev ◽  
Ingrid Artin ◽  
Oskar Hagberg ◽  
Elisabeth Borch ◽  
Elisabet Holst ◽  
...  

ABSTRACT The effects of carbon dioxide, sodium chloride, and sodium nitrite on type B botulinum neurotoxin (BoNT/B) gene (cntB) expression in nonproteolytic Clostridium botulinum were investigated in a tryptone-peptone-yeast extract (TPY) medium. Various concentrations of these selected food preservatives were studied by using a complete factorial design in order to quantitatively study interaction effects, as well as main effects, on the following responses: lag phase duration (LPD), growth rate, relative cntB expression, and extracellular BoNT/B production. Multiple linear regression was used to set up six statistical models to quantify and predict these responses. All combinations of NaCl and NaNO2 in the growth medium resulted in a prolonged lag phase duration and in a reduction in the specific growth rate. In contrast, the relative BoNT/B gene expression was unchanged, as determined by the cntB-specific quantitative reverse transcription-PCR method. This was confirmed when we measured the extracellular BoNT/B concentration by an enzyme-linked immunosorbent assay. CO2 was found to have a major effect on gene expression when the cntB mRNA levels were monitored in the mid-exponential, late exponential, and late stationary growth phases. The expression of cntB relative to the expression of the 16S rRNA gene was stimulated by an elevated CO2 concentration; the cntB mRNA level was fivefold greater in a 70% CO2 atmosphere than in a 10% CO2 atmosphere. These findings were also confirmed when we analyzed the extracellular BoNT/B concentration; we found that the concentrations were 27 ng · ml−1 · unit of optical density−1 in the 10% CO2 atmosphere and 126 ng · ml−1 · unit of optical density−1 in the 70% CO2 atmosphere.


Author(s):  
L. A. Chudinova ◽  
◽  
D. R. Yusupov ◽  

We studied the growth rate of rye seedlings, as well as the dynamics of the content of soluble proteins and proline in the shoots during their adaptation to sharp (300 mM NaCl once, exposure time 9 days) and gradual (100 mM NaCl, then 100 mM NaCl after 2 days to the final concentration of 400 mM) salinity with sodium chloride in the presence or absence of thermal hardening (+40°C, 3 h). The established dy-namics of the content of proline and soluble proteins in the shoots suggests that the formation of re-sistance to salinity is determined by the high constitutive level of proline, as well as the stress-inducible synthesis of proline and water-soluble proteins. Thermal pretreatment of the seedlings stimulated their constitutive stability to a greater extent. The detected metabolic changes are obviously related to one of the possible mechanisms of the protective effect of thermal hardening on subsequent salinization.


2021 ◽  
Vol 13 ◽  
Author(s):  
Sarita Kumari Yadav ◽  
Zulfequar Ahmed Khan ◽  
Brahmeshwar Mishra ◽  
Shiv Bahadur ◽  
Ajay Kumar ◽  
...  

: The objective of the present article is to provide an insight into the toxicity aspect of Nanoparticles on health and ecosystem along with risk assessment and monitoring. After a detailed screening of various research reports from the peer-reviewed journals, books, and research news, the article was prepared. Due to nanotechnology's various significant advantages over conventional technologies, it has been explored for diverse research and commercial needs such as cosmetics, medical, pharmaceuticals, biotechnology, electronics, catalysts, robotics, and so on. However, nanotechnology has several challenging elements for the health, environmental, societal and economic aspects, and unpredictable consequences can happen due to its unknown detailed nature, which needs to be identified. Therefore, in this review, an attempt has been made to cover the two most important aspects of the toxicity of nanoparticles i.e. influence on health and the ecosystem. The health hazards to various organs, especially lungs, gastrointestinal tract and dermis and aquatic organisms, have been elaborated. Further, the ecotoxicological aspect describing fate, mechanism of ecotoxicity, ecotoxicological challenges and solutions to ecotoxicologist are discussed. Risk assessments, related to the approaches that can be used for the optimization of nanotechnology, are also mentioned. Its high time when nanotechnology field needs reconsideration and uncompromising attention at a public and private level about its use, handling, storage, proper treatment and disposal. Also, risk analysis and establishment of regulatory guidelines for optimization and safe practice of nanotechnology for human and nature welfare are recommended.


2020 ◽  
Vol 12 (3) ◽  
pp. 482 ◽  
Author(s):  
Marek Kasprzak ◽  
Michał Łopuch ◽  
Tadeusz Głowacki ◽  
Wojciech Milczarek

The article presents geomorphological analysis results for two outwash fans (sandurs), Elveflya and Nottingham, in the marginal zone of the Werenskiold Glacier in the south-west part of the Spitsbergen. The main goal of this study was to reconstruct the morphological evolution of these landforms and to identify the permafrost zone under their surface. For this purpose, age data of fossils were compiled and compared with newly exposed and dated fossil tundra in the layer glaciotectonically deformed by the forming glacier end moraine. Using this method, a time frame was identified for the glacier advance and for the simultaneous formation of the outwash plains. It was concluded that the Elveflya surface has been built-up with deposits since the Little Ice Age. Sediment deposition ended in the late 1960s, due to hydrographic changes and the redirection of all proglacial waters towards the Nottingham bay. A photointerpretation analysis based on two orthophotomaps and LANDSAT scenes allowed the identification of five microfans in Elveflya, of which two youngest fans have a twice shorter range than the other three. The sixth microfan is currently shaped by deposits washed from the slope of the end moraine. An additional focus was placed on a currently active sandur, which fills the Nottingham bay, in order to identify its growth rate. The average growth rate of this surface increased from 5700 m2·year−1 over the period of 1985–2000 to 24,900 m2·year−1 over the period of 2010–2017. Electromagnetic measurements carried out on the surfaces of the sandurs demonstrated that the electrical resistivity of the ground is high in the apex of the Elveflya fan (ρ ≥ 1 kΩ.m) and low in its toe (typically ρ < 200 Ω.m), as in the case of the Nottingham fan ground. In the interpretation advanced here, permafrost developed in the proximal part of the Elveflya sandur, which continues to be supplied by fresh groundwaters flowing from the glacier direction. Low electrical resistivity of the ground in the distal part of the outwash fan suggests the absence of ground ice in this zone, which is subjected to the intrusion of salty and comparatively warm seawater, reaching approximately 1 km inland under the surface of the low-elevated marine terrace. The identified zones additionally display different tendencies for vertical movements of the terrain surface, as identified with the Small Baseline Subset (SBAS) method. The proximal part of the Elveflya outwash fan is relatively stable, while its distal part lowers in the summer period by a maximum of 5 cm. The resulting morphological changes include linear cracks having lengths up to 580 m and an arc line consistent with the coastline.


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