Agar/Agarose

Natural polymers polysaccharides (celullose, starch, pectins, dextrans, agar, agarose, alginate, chitine, chitosan, etc.) and fibrous proteins (collagen, keratine, etc.). 

The synthesis of indole alkaloids from the common precursors tryptamine and secologanin by cell cultures of C, roseus has been studied in detail (IT). Cells entrapped in agar, agarose, or carrageenan produce ajmalicine isomers at about the same rate as the freely suspended cells, while cells entrapped in alginate showed up to 160 fold increased synthesis. A major reason for this increased synthesis is believed to be the restricted growth of the entrapped cells, as has been discussed above for Capsiaum. The yield of ajmalicine is above 12 times as much product formed from added precursors as by de novo synthesis. In this case too, alginate entrapped cells were much more productive than freely suspended cells (140% increase), and were also used to synthesize the related alkaloid serpentine in a batch procedure (17). 

Unlike other naturally occurring polysaccharides, e.g., cellulose, dextran, pectin, alginic acid, agar, agarose and carrageenans, which are neutral or acidic in nature, chitosan is a highly basic polysaccharide. This unique property imparts several functional attributes such as polyoxysalt formation, ability to form films, chelation with metal ions, and optical structural characteristics (Hench 1998). 

All these separation modes can be performed in different instrumental formats. The first electrophoretic separations of proteins were performed by Tiselius in a free solution in a U-tube macrocuvette, allowing refraction index detection of boundaries of protein zones. Soon it was found out that the separation would be more efficient if performed in anti-convective stabilizing medium thus electrophoresis started to be performed in different carriers (paper, acetyl cellulose membrane) or in gel media (starch, agar, agarose, polyacrylamide (PAA)). In the last two decades electrophoresis has reverted to the free solution, stabilized by the anticonvective capillary effect of microbore (inner diameter (i.d.) <100pm)... 

Among the different gel matrices (starch, agar, agarose, PAA), especially the last two, agarose and PAA, are widely used for electrophoretic separations of proteins. 

Isoenzymes have usually been separated by zone electrophoresis on various carriers and identified by subsequent specific staining. Starch, agar, agarose, and polyacrylamide gels, cellulose acetate foils, and dex-trans such as Sephadex are the most commonly used carrier media. Markert and Mpller (1959) were the first to apply the technique of starch gel electrophoresis in separating dehydrogenases. Apart from the fact that such electrophoreses are easily carried out, they require only... 

At pH 7-9, these react with the free amino groups of the enzyme protein, with the formation of substituted imidocarbonates (=C=N-protein). Many other coupling techniques have been reported for the covalent attachment of enzymes to agar, agarose and Se-phadex supports, and to the silanized surface of porous glass. Details of these techniques and other aspects of immobilized enzymes are comprehensively treated in Methods in Enzymology, XUV, 1976, Klaus Mosbach, ed. Academic Press... 

The most widely distributed polysaccharides, cellulose, dextrans, pectins, alginic acid, agar-agar, agarose, starch and carrageenans, are either neutral or acidic substances. Chitin,... 

Agar, agarose Fanelli et al. (Allied-Signal Research and Technology) US Patent, 4,734,237,1988... 

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