Diffusion sugars

Root exudates Diffusates Sugars, organic acids, amino acids,... 

Reabsorption of the ligand plus its metal partner is a necessary requirement of processes like Fe acquisition by phytosiderophores (32). However, whether or not reabsorption of diffusates, which undoubtedly occurs in solution cultures (45), has a significant role to play is uncertain, largely because in soil most diffusates (sugars, amino acids, and other organic acids) are readily utilized by microorganisms or adsorbed by soil colloids. 

A possible explanation of the fact that our models predict D values that are larger than observed is now presented. Sugars and carboxylic acids form strong hydrogen bonds. If, for example, six water molecules are hydrogen-bonded to the diffusing sugar, the CMR value would be effectively too low ... 

Anon., BMA Cane Diffusion, Sugar y Azucar, p. 22, July 1970. 

The human organism hydrolyzes sucrose, lactose and oligosaccharides of the maltose and isomaltose type. The enzyme lactase, which is responsible for lactose hydrolysis, is lacking in some adults. Glucose and galactose are actively transported, while all other monosaccharides are transported only by diffusion. Sugar phospho-... 

Immersion extraction systems are usefiil in handling finely ground material or when the percolation rate through the material to be extracted is too rapid to aUow effective diffusion from the soHds. These systems are appHed extensively in the sugar industry, in extraction from oilseeds having a high oil... 

Nitrite is usuaUy one indicator of the infection level in the diffuser. Exposure of nitrite to sulfur dioxide, either as a diffusion additive or later to thin juice, results in the production of potassium imidodisulfonate which precipitates when sugar is later crystallized, a cause of turbid or cloudy sugar. 

Sugar-beet cossettes are successfully extracted while being transported upward in a vertical tower by an arrangement of inclined plates or wings attached to an axial shaft. The action is assisted by staggered guide plates on the tower wall. The shell is filled with water that passes downward as the beets travel upward. This configuration is employed in the BMA diffusion tower (Wakeman, loc. cit.). 

Explds at 60° after 13 sec in a sealed glass tube (Ref 4). Explds spontaneously when frozen and then thawed. Compd is a violent expl, extremely sensitive to impact or friction. It Jalso explds on exposure to strong light (sunlight or diffused), or when in contact with P, As, ozone, fused alkalies, and organic matter such as turpentine rubber, but not with sugar or resins. Metals strong acids do not cause it to expld,... 

The simplest way to prepare a biocatalyst for use in organic solvents and, at the same time, to adjust key parameters, such as pH, is its lyophilization or precipitation from aqueous solutions. These preparations, however, can undergo substrate diffusion limitations or prevent enzyme-substrate interaction because of protein-protein stacking. Enzyme lyophilization in the presence of lyoprotectants (polyethylene glycol, various sugars), ligands, and salts have often yielded preparations that are markedly more active than those obtained in the absence of additives [19]. Besides that, the addition of these ligands can also affect enzyme selectivity as follows. 

Facilitated diffusion and active transport share many features. Both appear to involve carrier proteins, and both show specificity for ions, sugars, and amino acids. 

With few exceptions, small particles of vegetable foods are generally stripped of their more accessible nutrients during digestion in the GI tract. In this way starch, protein, fat and water-soluble small components (sugars, minerals) are usually well absorbed. This is not always the case, however, for larger food particles or for molecules that cannot diffuse out of the celF tissue. Neither is it the case for the lipid-soluble components. These need to be dissolved in lipid before they can be physically removed from the cell to the absorptive surface, since the cell wall is unlikely to be permeable to lipid emulsions or micelles, and the presence of lipases will strip away the solvating lipid. 

The phosphorylation of cytoplasmic sugar and the facilitated diffusion from the cytoplasm to the periplasm are catalyzed by the E-IIs under conditions where they are also active in the vectorial phosphorylation reaction. Therefore, the former two activities should be integral parts of any kinetic scheme representing the mechanism of E-IIs. Such a scheme should explain how vectorial phosphorylation, transport coupled to phosphorylation, is still achieved while the uncoupled pathways are integral parts of the scheme. 

Diffusion-mediated release of root exudates is likely to be affected by root zone temperature due to temperature-dependent changes in the speed of diffusion processes and modifications of membrane permeability (259,260). This might explain the stimulation of root exudation in tomato and clover at high temperatures, reported by Rovira (261), and also the increase in exudation of. sugars and amino acids in maize, cucumber, and strawberry exposed to low-temperature treatments (5-10°C), which was mainly attributed to a disturbance in membrane permeability (259,262). A decrease of exudation rates at low temperatures may be predicted for exudation processes that depend on metabolic energy. This assumption is supported by the continuous decrease of phytosiderophore release in Fe-deficient barley by decreasing the temperature from 30 to 5°C (67). 

Sugar (sucrose) is obtained from either sugar beets or sugarcane. Sugar beets are traditionally diffused with water to extract the sugar from the pulp. The sugar is then crystallized, mechanically separated, and washed to produce white sugar. 

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