Carbohydrate colloids

See also Biotechnology (Bioprocess Engineering) Carbohydrates Colloid Systems Genetics and Gene Science (Classical) and Industrial Biotechnology. 

The role of carbohydrate colloids in wine clarification and stability has been studied much more extensively. Pectic substances in wine foul filter layers (Castino and Delfini, 1984) during filtration. This phenomenon is particularly marked in tangential microfiltration (Section 11.5.2) (Feuillat and Bernard 1987 Serrano et al., 1988) as the carbohydrate colloid retention rate may be over 50%. A much higher proportion of AGPs than yeast mannoproteins is retained in this process (Brillouet et al., 1989 Belleville et al., 1990). 

Yeasts are the second major source of polysaccharides in wine. A great deal of research has been devoted to the structure of yeast cell walls (Volume 1, Section 1.2), but much less to the type of carbohydrate colloids released into wine. 

Class of colloidal substances prepared from plants. Composed of complex carbohydrates and organic acids that swell in water. Also, a number of natural resins are gums. 

Somewhat in advance of the widespread usage of the colloidal connotation of Ostwald and others, investigators in a number of instances seem to have favored the view that cellulose, starch, rubber, etc., are polymeric, the term being used in much the same sense as it is used today. The idea that proteins and carbohydrates are polymeric goes back at least to Hlasiwetz and Habermann, who, in 1871, considered... 

More recently, Brauns and Seiler (12), (13) extracted native lignin from spruce wood and then homogenized the wood in a colloidal mill. A suspension of approximately one gram of colloidal wood per liter of water was obtained. After the colloidal wood was changed to a solid form, it was found that its cell structure was completely destroyed. However, extraction of this wood with ethyl alcohol at room temperature did not yield further quantities of native lignin. These investigators have also reported the isolation of a lignosulfonic acid-carbohydrate compound. 

The chemistry is both wide ranging and interesting. It involves carbohydrate chemistry, the chemistry of inorganic pigments, organic resins —both natural and synthetic—and many other organic and polymeric additives. The sheet formation process also involves a considerable amount of colloid and surface chemistry. Polymer chemistry and environmental and analytical chemistry also play an important part. 

Fiebrig, L, Varum, K.M., Elarding, S.E., Davis, S.S., and Stokke, B.T. Colloidal gold and colloidal gold labelled wheat germ agglutinin as molecular probes for identification in mucin/ chitosan complexes, Carbohydr. Polym., 33 91-99 (1997). 

Guo CX, Boullanger P, Jiang L, Liu T. Colorimetric detection of WGA in carbohydrate-functionalized polydiacetylene Langmuir-Schaefer films. Colloids Surf Physicochem Eng Asp 2007 293 152-156. 

The challenge with parenteral iron therapy is that parenteral administration of inorganic free ferric iron produces serious dose-dependent toxicity, which severely limits the dose of that can be administered. However, when the ferric iron is formulated as a colloid containing particles with a core of iron oxyhydroxide surrounded by a core of carbohydrate, bioactive iron is released slowly from the stable colloid particles. In the USA, the three available forms of parenteral iron are iron dextran, sodium ferric gluconate complex, and iron sucrose. 

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