Cell walls sodium carbonate

Cell wall were isolated (2) and the pectic polysaccharides were extracted according with their solubility on water (highly esterified polysaccharides), imidazolium (ionically linked polysaccharides) and sodium carbonate (covalent linked polysaccharides), as shows figure 1. 

Dried fractions should be white. The proportions recovered by the different chemical treatments will be different, depending on the composition of the cell walls however, traditionally, most of the pectic polysaccharides are extracted in the water-soluble fractions (during cell wall isolation), CDTA, and sodium carbonate fractions, but a small proportion is often found in the final residue. Hemicelluloses are usually extracted by 1 M and 4 M KOH. The final residue is predominantly cellulose. 

Such elements are readily obtained from low grade flour, which is sieved and the residue washed to free it completely from the small amount of adherent flour. Before observing this residue under the microscope, it is well to heat it to incipient boiling with a 10% solution of sodium carbonate, which dissolves the cell-contents of the tissues and renders more distinct the structure of the walls. 

A part of the cell wall fraction was extracted with 0.25M sodium hydroxide at 4°C for 24hr and the extract was then subjected to pronase digestion to remove protein. The digested extract was chromatographed on a DEAE cellulose column by stepwise elution with water, sodium bicarbonate and sodium hydroxide. The yield of the major fraction, which was eluted with 0.5M sodium bicarbonate, SE, was 20.3% of the cell wall by weight. Another part of ACW was extracted successively with 45% phenol-water(PE), then with hot water in an autoclave(HE), and finally with 1% potassium carbonate at room temperature for 24hr(PCE). The yields of these fractions, PE, HE and PCE were 0.47%, 0.27% and 4.4%, respectively. 

The carbon monitors applied for the determination of carbon activities in lithium or sodium apply diffusion cells. Carbon dissolved in alkali metals contacting the probes diffuses through the probe wall, a thin tube wall of pure iron. The diffusing carbon in consumed by chemical reactions in the probe ... 

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