Osmotic stress, effect

In making the reasonable assumption that browser diets should have remained consistent through time, it was also assumed that C7 C ratios of their C3 foliage diets would not have changed. This is not the case environmental parameters such as aridity, osmotic stress, temperature, pCOi and irra-diance have predictable effects on ratios of C3 plants (summarized in... 

Jones, H.G. (1973). Photosynthesis by thin leaf slices in solution. II. Osmotic stress and its effects on photosynthesis. Australian Journal of Biological Sciences, 26, 25-33. 

Cells selected for tolerance to water stress have been demonstrated in a number of plant species (Handa et al., 1983 Heyser Nabors, 1981 Stavarek Rains, 1984b). High molecular weight PEG is commonly used to induce water deficits (Hasegawa et al., 1984). This provides an opportunity to evaluate intracellular osmotic adjustment of plants exposed to water stress. If information is desired on the effect of specific osmotic substances on cellular adjustment to osmotic stress PEG can be used as an independent osmotic regulator and/or in combination with an absorbable osmoticum. In these situations the interaction of osmoticum produced by the cell with the osmoticum absorbed by the cell can be evaluated. 

McKenney, C.L., Jr. and D.B. Hamaker. 1984. Effects of fenvalerate on larval development of Palaemonetes pugio (Holthuis) and on larval metabolism during osmotic stress. Aquat. Toxicol. 5 343-355. 

Graney, R.L. and J.P. Giesy, Jr. 1987. The effect of short-term exposure to pentachlorophenol and osmotic stress on the free amino acid pool of the freshwater amphipod Gammarus pseudolimnaeus Bousfield. Arch. Environ. Contam. Toxicol. 16 167-176. 

Rastogi, N.K., Angersbach, A., and Knorr, D. 2000b. Synergistic effect of high hydrostatic pressure pre-treatment and osmotic stress on mass transfer during osmotic dehydration. J. Food Engineer. 45, 25-31. 

Bibette has used this method to study the effect of osmotic pressure on the stability of thin films in concentrated o/w emulsions [96], by means of an osmotic stress technique. The emulsion is contained in a dialysis bag, which is immersed in an aqueous solution of surfactant and dextran, a water-soluble polymer. The bag is permeable to water and surfactant, but impermeable to oil and polymer. The presence of the polymer causes water to be drawn out of the emulsion, increasing the phase volume ratio and the deformation of the dispersed droplets (Fig. 10). 

We have used osmotic stress (4) to examine the effect of Mg2 and Ca2 on the interactions between dioleoylphospha-tidylcholine or dipalmitoyl phosphatidyl choline bilayers. From the net repulsive forces between bilayers we are able to infer electrostatic potentials and charge densities at the site of ion binding these quantities are sensitive to bilayer separation. We find that at any particular bilayer separation dioleoyl phosphatidyl choline bilayers (melted hydrocarbon chains) adsorb less charge than dipalmitoyl phosphatidyl choline bilayers (frozen hydrocarbon chains) and that the binding of Ca2 is greater than that of Mg2 for both kinds of bilayers. 

The compactness of nucleosomes has been found to depend on osmolality (Bednar et al., 1995), albeit the impacts of this effect on gene expression remain to be established. Changes in chromatin structure induced by osmotic stress could be offset by alterations in histone proteins. Certain histones of mammalian cells are... 

Meury, J. (1988). Glycine betaine reverses the effects of osmotic stress on DNA replication and cell division in Escherichia coli. Arch. Microbiol. 149 232-239. 

Petronini, P., W. De Angelis, A. Borghetti, and K. Wheeler (1993). Effect of betaine on HSP70 expression and cell survival during adaptation to osmotic stress. Biochem. J. 293 553-558. 

The uptake and accumulation of various amino acids in Lactobacillus arabinosus have been described. An extensive investigation of this process using cells deficient in vitamin B6, biotin, and pantothenic acid has shown that all these deficiencies markedly alter the transport process. Accumulation capacity is most severely decreased by a vitamin B6 deficiency. The evidence now available indicates that this does not reflect the direct participation of the vitamin in the transport process, but rather is an indirect effect arising from the synthesis of an abnormal cell wall which renders the cell unusually sensitive to osmotic stress. Amino acid transport in vitamin B6-deficient cells is restored to normal levels by raising the extracellular osmotic pressure or by enabling the cells to synthesize additional wall substance. 

Y. C. Yang, M. Bestos and K. J. Chen (1993). Effect of osmotic stress and growth stage on cellular pH and polyphosphate metabolism in Neurospora crassa as studied by 31-P-nuclear magnetic resonance spectroscopy. Biochim. Biophys. Acta, 1179, 141-147. 

Jones, B. E. 1968. Effects of extending periods of osmotic stress on water relationships of pepper. Physiol. Plant. 21 334-345. 

Yeast strain, and nutrient status of the must and fermentation conditions, many of which affect growth or induce physiological stress, modulate the accumulation of acetic and other fatty acids in wine. Reported factors include must sugar concentration, nutrient balance, inoculum level, fermentation temperature, pH and aeration (Delfini and Costa 1993 Henschke and Jiranek 1993 Shimazu and Watanabe 1981). The effects of osmotic stress, as induced by sugar concentration, on acetic acid production are discussed in Sect. 8D.3.2. 

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