Polysaccharides matrices

Fluvial biofilms (also known as phytobenthos or periphyton) are attached communities consisting of bacteria, algae and fungi embedded within a polysaccharide matrix [20]. In rivers, these communities are the first to interact with... 

Biofouling involves the formation of biofilm, whereby hydrated algal- or bacterial-based slimes adhere to water-wetted cooling system surfaces and often contain scales, corrosion products, or other debris embedded within a polysaccharide matrix. The role of biofilms in reducing cooling system efficiency and life span is still imperfectly understood. 

Freeman, C., and M. A. Lock. 1995. The biofilm polysaccharide matrix-a buffer against changing organic substrate supply Limnology and Oceanography 40 273-278. 

CMD and mixed derivatives based on CMD may be used for the fixation of antibiotics and enzymes on a polysaccharide matrix. A procedure was developed for amidation of CMD and its ethyl ester (CMDEE) with various aromatic amines in dioxane (100 °C), ethanol (78 °C), n-propanol (97 °C) and 2-propanol (82 °C) in the presence of a small amount of water [301]. CMDEE reacts with aliphatic and aromatic amines but in the case of amino acids the degree of amidation depends on the position of the amino moieties in the acids [302,303]. The DS decreases from S-, y-, /3, to a-amino acids. For the reaction with a-amino acids, carboxymethyl and carboxyethyl dextran azides are used [304],... 

Nitrophenyl chloroformate activation. The reaction of polysaccharides with chloroformates forming reactive carbonate derivatives has often been used to link bioactive compounds, such as affinity ligands and enzymes, onto polysaccharide matrixes. It was reported that upon reaction with ethyl chloroformate cyclic carbonate as well as ethyl-carbonate structures are formed (9-13). Activation with N-succinimi-do chloroformate (14), 2,4,5-trichloroformate (14) and 4-nitrophenyl chloroformate (14, 15) reportedly led to the introduction of pending carbonate moieties. 

In the pH range close to the protein s lEP an interesting phenomenon of non-uniform redistribution of protein molecules among polysaccharide chains occurs (Tolstoguzov et al. 1985). The reason is that in the vicinity of the protein lEP the hydrophobic protein-protein and electrostatic protein-polysaccharide interactions can be energetically comparable with each other. Protein-protein association on the anionic polysaccharide matrix (or self-association of proteins), which is mainly due to hydrophobic interactions, is usually enhanced when the pH approaches the protein lEP. Accordingly, under conditions of a relatively weak protein-polysaccharide interaction, each free site situated near the site on the polysaccharide chain already occupied by a protein molecule becomes thermodynamically preferable for further binding of protein molecules. This leads to cooperative protein adsorption on an anionic polysaccharide. Some parts of polysaccharide chains tend to be completely covered by protein molecules (as in a virus) while other parts are completely free of protein. 

The data of Table 2 strongly indicate that the motion of calcium ions is markedly slower than that which could be expected in case of simple diffusion. This emphasises the role of the polysaccharide matrix in trapping these ions and the preference of PGA for complexing the divalent calcium ions. 

Biliaderis, C.G., Lazaridou, A., Mavropoulos, A., and Barbayiannis, N. Water plasticization effects on crystallization behavior of lactose in a co-lyophilized amorphous polysaccharide matrix and its relevance to the glass transition, Int. 

Transparent exopoly-meric particles (TEP) [8,19] 3-100 pm off California coast microscopy after Aldan blue staining 3 X 10 -5 X 10 polysaccharide matrix with high water content flexible, deformable, filmy , gel-hke... 

It is clear from the accunulated evidence that the stabilization energy of the complex can be realized only if the triiodide ion is present. Moreover, I has a considerably higher affinity for the polysaccharide matrix than does I in the absence of cooperative interactions along the polyiodine chain (3, 2 ). These circumstances suggested to us that the complexation process is... 

It is known that the cell walls consist of various layers the primary wall (P), the secondary wall which is divided into three sublayers (the outer SI, middle S2, and inner S3), and the midlle lamella (ML). Lignin deposition proceeds in different phases, each preceded by the deposition of carbohydrates, and starts at the cell comers in the region of the middle lamella and the primary wall when SI formation has initiated. When the formation of the polysaccharide matrix of the S2 layer is completed, lignification proceeds through the secondary wall. The bulk of lignin is... 

Synthetic Bioactive Units BiopolymCTs Proteins, Polysaccharides Matrix Assemblies and Supramolecular Structures... 

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