Salinity lipid compositions

Kuiper P.J.C. Functioning of plant cell membranes under saline conditions membrane lipid composition and ATP ses. In "Salinity tolerance in plants" Richard C. Staples, G.H. Toennisen, J. Wiley and sows Ed., New york, 1984, 77-91. 

Figure 3. Comparison of experimental results with the classical "lipid barrier model". Symbols and dashed curves (A,B,C) represent experimental data. A) saline in the donor compartment, ethanol in respective volume fractions between 0 and 1 in the receiver compartment B) equal compositions of ethanol/saline mixtures in volume fractions between 0 and 1 in donor and receiver compartment. C) saline in the receiver compartment, ethanol/saline in volume fractions between 0 and 1 in donor compartment. A, B and C represent theory based on the "lipid barrier model".

There are many interacting external (temperature, salinity, food availability) and internal factors, including species, sex, physiological status (gonad maturity, condition, age), that determine and affect the lipid content and composition of aquatic organisms. The (n-3) PUFA are essential for the normal development of embryos, larvae, and the nervous system, and for the proper functioning of the sense organs of marine and freshwater fish. 

Normal adipose tissue and lipomas from each patient were excised, washed several times with saline and homogenized From this homogenate the lipids were extracted Total lipids were measured in this extracts and then the composition of the neutral lipids was determined by means of thinlayer chromatography ( ) ... 

Lipid extracts obtained from biological samples, as aforementioned, tend to contain significant amounts of nonlipid contaminants, such as sugars, amino acids, urea, and salts. These must be removed before the lipids are analyzed. A common and classical approach is to use a simple washing procedure devised by Folch, Lees and Sloane Stanley [17], in which a chloroform-methanol (2 1, v/v) extract is shaken and equilibrated with one-fourth its volume of saline solution (i.e., 0.88% potassium chloride in water). The mixture partitions into two layers, of which the lower phase is comprised of chloroform-methanol-water in a proportion of 86 14 1 (by volume) and contains virtually all of the lipids, while the upper phase consists of the same solvents in the proportion of 3 48 47 (by volume), respectively, and contains much of the nonlipid contaminants. It is important that the proportion of chloroform, methanol, and water in the combined phases should be as close as possible to 8 4 3 (by volume), otherwise selective losses of lipids may occur. If a second wash of the lower phase is needed to remove any remaining contaminants, a mixture of similar composition to that of the upper phase should be used, i.e., methanol-saline solution (1 1, v/v). 

Plasma root membranes play an important role in the ability of plants to cope with salinity. Indeed PM exercises a high degree of control on ion fluxes via their H+ pumps and transport proteins. More precisely, the chemical structure and physical state of the lipid environment (in particular sterol) is important for membrane protein function. Therefore we have chosen to study the sterol composition of root PM to gain further insight into the mechanism of Na" " exclusion. 

Zhu, L., Zhang, X., Ji, L., Song, X., Kuang, C., 2007. Changes of lipid content and fatty acid composition of Schizochy-trium limacinum in response to different temperatures and salinities. Process Biochemistry 42 (2), 210-214. 

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