Equilibrium and Dynamic Osmotic Behaviour of Aqueous Solutions with Varied Concentration at Constant and Variable Volume

Osmosis is essential for the living organisms. In biological systems the process usually occurs in confined volumes and may express specific features. The osmotic pressure in aqueous solutions was studied here experimentally as a function of solute concentration (0.05–0.5 M) in two different regimes: of constant and variable solution volume. Sucrose, a biologically active substance, was chosen as a reference solute for the complex tests. A custom made osmotic cell was used. A novel operative experimental approach, employing limited variation of the solution volume, was developed and applied for the purpose. The established equilibrium values of the osmotic pressure are in agreement with the theoretical expectations and do not exhibit any evident differences for both regimes. In contrast, the obtained kinetic dependences reveal striking divergence in the rates of the process at constant and varied solution volume for the respective solute concentrations. The rise of pressure is much faster at constant solution volume, while the solvent influx is many times greater in the regime of variable volume. The results obtained suggest a feasible mechanism for the way in which the living cells rapidly achieve osmotic equilibrium upon changes in the environment.

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Neutral Lipids of Oats Fruit (Avena Sativa L.)

Drug development & registration ◽

10.33380/2305-2066-2020-9-4-40-43 ◽

2020 ◽

Vol 9 (4) ◽

pp. 40-43

Author(s):

N. K. Yuldasheva ◽

S. D. Gusakova ◽

D. Kh. Nurullaeva ◽

N. T. Farmanova ◽

R. P. Zakirova ◽

...

Keyword(s):

Avena Sativa ◽

Neutral Lipids ◽

The Body ◽

Biologically Active ◽

Absorption Bands ◽

Vital Functions ◽

The Republic ◽

Living Organisms ◽

Main Components ◽

Active Substances

Introduction. Lipids are a widespread group of biologically active substances in nature, making up the bulk of the organic substances of all living organisms. They accumulate in plants in seeds, as well as in fruits and perform a number of vital functions: they are the main components of cell membranes and the energy reserve for the body.Aim. Study of neutral lipids of sown oats (Avena sativa L.).Materials and methods. The objects of the study were fruits (grains) of oats of the sown variety "Tashkent 1," harvested in the Republic of Uzbekistan. Results and discussions. Neutral lipids of oat grains have been found to contain 13 fatty acids with a predominance of the sum of oleic, linolenic and linoleic acids. The total degree of unsaturation was almost 78%. Absorption bands characteristic of these substances were observed in the IR spectrum of MEGC.Conclusion. According to the results of the NL analysis, oat grains consisted of triacylglycerides and free LCDs, which were accompanied by hydrocarbons, phytosterols, triterpenoids and tocopherols.

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INTERACTIONS IN AQUEOUS SOLUTIONS. II. OSMOTIC PRESSURE AND OSMOTIC COEFFICIENT OF SUCROSE AND GLUCOSE SOLUTIONS

The Journal of Physical Chemistry ◽

10.1021/j100830a028 ◽

1960 ◽

Vol 64 (1) ◽

pp. 118-124 ◽

Cited By ~ 17

Author(s):

D. Stigter

Keyword(s):

Aqueous Solutions ◽

Osmotic Pressure ◽

Osmotic Coefficient

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Motions of water molecules in dilute aqueous solutions of tertiary butyl alcohol; a neutron scattering study of hydrophobic hydration

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1970.0174 ◽

1970 ◽

Vol 319 (1537) ◽

pp. 189-208 ◽

Cited By ~ 28

Keyword(s):

Aqueous Solutions ◽

Water Structure ◽

Hydrophobic Hydration ◽

Step Length ◽

Solute Concentration ◽

Butyl Alcohol ◽

Tertiary Butyl ◽

Self Diffusion ◽

Dilute Aqueous Solutions ◽

Neutron Scattering Study

Cold neutron inelastic scattering experiments have been performed on dilute aqueous solutions of (CD 3 ) 3 COH and of solutions of (CH 3 ) 3 COH in D 2 O at 21 °C. From the broadening of the quasi-elastic peak and independently determined self-diffusion coefficients ( D ), diffusive lifetimes ( c ) of H 2 O molecules have been calculated as functions of solute concentration. The product Dc is insensitive to concentration, giving a mean diffusion step length of 0.14 nm. The inelastic portion of the spectrum, reflecting lattice-like hydrogen bonding modes indicates that the solute enhances the water ‘structure’ but that such structure bears no resemblance to ice.

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Osmotic equilibria in fibroblasts in tissue culture measured by immersion refractometry

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1958.0057 ◽

1958 ◽

Vol 149 (934) ◽

pp. 130-143 ◽

Cited By ~ 5

Keyword(s):

Water Content ◽

Osmotic Pressure ◽

Regression Line ◽

Fluid Medium ◽

Physiological Conditions ◽

Chick Heart ◽

Osmotic Behaviour ◽

Osmotic Properties ◽

Saline Medium

Volume-osmotic pressure relationships at equilibrium have been obtained in chick heart fibroblasts grown in slide-coverslip cultures in a fluid medium consisting of heparinized plasma and embryo extract. The refractive index of the fibroblast gives a direct measure of its solid concentration, and the volume is estimated as the reciprocal of concentration. The volume is found to be linearly related to the reciprocal of the osmotic pressure over a range from 130 to 587 m-osm, provided the measurements are carried out rapidly at 38°C. The isotonic water content of the cells derived from the gradient of the regression line on the basis of the simple Boyle-van’t Hoff Law was found to be less than actual water content obtained by direct refractometry, i. e. the value of Ponder’s ℛ was 0⋅94 (s. d. 0⋅04). In cultures grown in a simple saline medium and measured at 22°C the volume was related linearly to the reciprocal of the osmotic pressure only between the limits of 330 and 191 m-osm. Outside these limits the volume was greater than expected and this was attributed to alterations in the semi-permeable properties of the cell membrane. The value of Ponder’s ℛ in these cultures was 1⋅15. The importance of the quantity, ℛ, as applied to cells other than the erythrocyte, is indicated. The value, 0⋅94 (s. d. 0⋅04), obtained in fibroblasts under physiological conditions is not explicable on the basis of the probable osmotic properties in vitro of the cell proteins. The discrepancy is within the experimental error, but it may also be due to abnormal osmotic behaviour of the cell proteins resulting from some form of intermolecular structure in the cytoplasm.

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Medical and biological functions of water

Farmatsevtychnyi zhurnal ◽

10.32352/0367-3057.3.19.08 ◽

2019 ◽

pp. 65-75

Author(s):

R. S. Korytniuk ◽

L. L. Davtian ◽

N. I. Hudz ◽

A. A. Drozdova ◽

I. О. Vlasenko ◽

...

Keyword(s):

Osmotic Pressure ◽

Active Compound ◽

The Body ◽

Biologically Active ◽

Biological Functions ◽

Salt Balance ◽

Biologically Active Compound ◽

Water Salt ◽

Excessive Intake ◽

Pharmaceutical Practice

Water is the most common compound of hydrogen and oxygen in the nature. It is a universal solvent of many substances, and therefore chemically pure water does not exist in the nature. The water contained in the body is qualitatively different from ordinary water as it is structured water. Such crystalline structures of water are the matrix of life. Their presence gives possibility of the occurrence of important biophysical processes and biochemical reactions. Insufficient intake of water into the body or its excessive loss leads to dehydration, which is accompanied by thickening of the blood and impairing hemodynamics. Excessive intake of water into the body causes water intoxication. Purpose – to conduct a bibliosemantic analysis of the sources of the literature on the medical and biological functions of water. Research methods – bibliosemantic, analytical, logical methods and generalizion method. Water is the structural basis of cells necessary to maintain their optimal volume. It determines the spatial structure and function of biomolecules. Insufficient intake of water into the body or its excessive loss leads to an impaired hemodynamics. Excessive intake of water into the body causes water intoxication. All disoders of water-salt balance in the body can be divided into two groups: dehydration and hyperhydration. In each group, there are disorders with a decrease, increase, and no change in osmotic pressure (hypotonic, hypertonic, and isotonic disorders, respectively). Water is used in medical and pharmaceutical practice as an excipient, and for the manufacture of allopathic, homeopathic and anthroposophic medicines. The State Pharmacopoeia of Ukraine includes several articles on the use of water depending on the purpose and regulates water quality: 1) highly purified water, water for injections «in bulk» water and sterilised water for injections; 2) purified water: water «in bulk» and water in containers. Cosmetics are presented on the Ukrainian market, the main biologically active compound of which is water, in particular, natural, thermal and micellar. They are widely used in cosmetology. The biomedical function of water in the body is to preserve cell volume, provide turgor to the cells and save the body from temperature fluctuations. Disruption of water-salt balance leads to dehydration or hyperhydration. There are changes with a decrease, increase, and no change in osmotic pressure (hypotonic, hypertonic, and isotonic disorders, respectively). They cause disruption of the life of the whole organism. In pharmaceutical practice, water is widely used for the manufacture of allopathic, homeopathic and anthroposophic medicines. It can be obtained in various ways, but its quality is regulated by the relevant government regulations. In cosmetic practice, water is used not only as a basic solvent, but in the form of natural, micellar and thermal water, where it is a biologically active compound.

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Nematocidial activity of aqueous solutions of plants of the families Cupressaceae, Rosaceae, Asteraceae, Fabaceae, Cannabaceae and Apiaceae

Biosystems Diversity ◽

10.15421/011931 ◽

2019 ◽

Vol 27 (3) ◽

pp. 227-232 ◽

Cited By ~ 4

Author(s):

O. O. Boyko ◽

V. V. Brygadyrenko

Keyword(s):

Aqueous Solutions ◽

Cannabis Sativa ◽

Root Zone ◽

Taraxacum Officinale ◽

Ambrosia Artemisiifolia ◽

Biologically Active ◽

Parasitic Nematodes ◽

Foeniculum Vulgare ◽

Conium Maculatum ◽

Nematode Larvae

In natural ecosystems of animals, introduction of larvae of parasitic nematodes into the litter layer from excrement facilitates their migration and search of new host vertebrate animals. In such conditions they are constantly affected by biologically active substances of the abundant species of plants which grow in pastures. Currently, the influence of substances present in the above-ground part of plants on the vitality of larvae of helminths in the environment remains unstudied. In this article, we present the results of our research on the nematocidial activity in vitro in the aqueous solutions of 21 species of plants distributed in the territory of Steppe Ukraine: Sanguisorba officinalis L., Rosa canina L., Crataegus sanguinea Pall., Crataegus pentagyna Waldst. & Kit. ex Willd., Armeniaca vulgaris Lam., Taraxacum officinale F. H. Wigg., Iva xanthiifolia Nutt., Artemisia campestris L., Arctium minus (Hill) Bernh., Ambrosia artemisiifolia L., Cannabis sativa L., Humulus lupulus L., Melilotus officinalis (L.) Pall., Vicia cracca L., Lotus ucrainicus Klok., Onobrychis arenaria (Kit.) DC., Foeniculum vulgare Mill., Eryngium planum L., Conium maculatum L., Juniperus communis L., Thuja occidentalis L. The level of vitality of nematode larvae of the Strongylida (Haemonchus contortus (Rudolphi, 1803)) and Rhabditida (Strongyloides papillosus (Wedl, 1856)) orders varied depending on the species of plant, and also five experimental concentrations in aqueous solutions tested in seven replications. The most notable nematocidial effect was exerted by Taraxacum officinale F. H. Wigg. – we observed death of larvae of third stage development L3 H. contortus and larvae of first-third stages L1–3 S. papillosus at 24 h exposure to 3% aqueous solution. Three percent aqueous solutions of S. officinalis and A. artemisiifolia displayed nematocidial properties only against S. papillosus: death of L1–3 S. papillosus was observed. Aqueous solutions of R. canina, A. vulgaris, A. minus, H. lupulus, V. cracca, L. ucrainicus, O. arenaria, E. planum, C. maculatum, J. communis, Th. occidentalis had lethal effect only on non-invasive larvae (larvae of the first and second stage L1–2) of S. papillosus. They displayed no nematocidial properties towards invasive larvae of H. contortus and S. papillosus. At exposure to aqueous solutions of the rest of the studied species of plants, over 50% of L3 H. contortus and L1–3 S. papillosus larvae remained alive. The determined patterns allow us to state that while living in the litter and soil in the root zone of plants nematode larvae undergoa negative influence caused by some plant species.

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