Inulin utilization

Bio-Gel P-6 and a combined system of P-6/S-200 were utilized for investigations of inulin-type /3(2- l)-linked nb fructans. With a flow rate of 0.33 mP min, each separation of a sample volume of 1 ml of a 20- to 30-mg/ml concentrated solution typically lasted 20 hr, i.e., one run per day. Both systems (P-6 and P-6/S-200) maintained stability for approximately 1 year, equivalent to approximately 100 runs. 

Most contrast agents elicit nephrotoxicity because they are primarily excreted by the kidneys. However, when administered in small doses, they constitute a rich source of GFR markers. The two major classes of contrast agents that are finding clinical utility as GFR markers are iodinated aromatic compounds and metal complexes. lodinated aromatics such as iohexol and iothalamate (Fig. 13) are commonly used as contrast agents for computed tomography (GT). They also have pharmacokinetics similar to inulin and hence are useful indicators of renal status [215]. The iodinated molecules used for GFR measurements consist of a triiodo-benzene core and hydrophilic groups to enhance solubility in aqueous medium. 

Two yeasts that utilize inulin have been examined, namely, Candida salmanticensis404 andDebaryomyces polymorphus (cantarellii).40S The former released inulinase into the culture medium and, when purified, this enzyme gave the following values of K 17 mM inulin, 43 mM sucrose, and 2 mM raffinose, with an optimum at pH 4 for all three... 

The present utilization of carbohydrates as a feedstock for the chemical industry is modest, when considering their ready availability, low cost and huge potential [92], The bulk of the annually renewable carbohydrate biomass consists of polysaccharides, but their non-food utilization is still modest. The low-molecular-weight carbohydrates, that is, the constituent units of these polysaccharides, are potential raw materials for several commodity chemicals in fact, glucose (available from cornstarch, bagasse, molasses, wood), fructose (inulin), xylose (hemicelluloses) or the disaccharide sucrose (world production 140 Mtons year-1) are inexpensive and available on a scale of several ten thousands. 

Unlike most crops that store carbon as starch, a polymer of glucose, in the Jerusalem artichoke carbon is stored as inulin, a fructose polymer. The implications of this have a pronounced influence on the value and utility of the crop. An extremely important attribute derived from inulin is its nutritional contributions, even though the caloric value in humans is low. The evidence for the role of inulin in decreasing blood cholesterol and in enhancing other positive health benefits has been firmly established. 

Jerusalem artichoke therefore has potential as a multipurpose crop, with the value of its byproducts a key to its future commercial exploitation. A listing of patents that relate to Jerusalem artichoke (Appendix), particularly utilizing plant-derived inulin, illustrates an increasing interest in the crop. 

Both the quantity and quality of inulin in various plant sources are of considerable importance in terms of its utilization. Both Jerusalem artichoke and chicory have inulin contents of >15% on... 

Isolated inulinase is utilized for either batch hydrolysis of inulin or immobilization for flowthrough column hydrolysis systems. For example, purified inulinase from K. fragilis has been immobilized on 2-aminoethyl cellulose (Kim et al., 1982). 

D-Mannitol has a diverse range of industrial applications. It is a nonhydroscopic, low-calorie, noncariogenic sweetener utilized by the food industry as well as a feedstock for the synthesis of other compounds. For example, mannitol can be oxidized at the 3 or 4 position to form two molecules of glyceraldehyde or glyceric acid, which can be used as building blocks for other compounds (Heinen et al., 2001 Makkee et al., 1985 van Bekkum and Verraest, 1996). Mannitol is formed from inulin via hydrolysis followed by catalytic hydrogenation. This yields mannitol and sorbitol from which the mannitol can be readily crystallized (Fuchs, 1987). Currently mannitol is primarily synthesized from starch. 

Inulin carbonate can be synthesized with ethyl chloroformate in dimethyl sulfoxide with triethy-lamine as the catalyst (Figure 5.5) (Kennedy and Tun, 1973). This yields a mixture of two products one with O-ethoxycarbonyl groups (5) and the second with trans-4,6-carbonate (6) on the fructo-furanose groups of the inulin chain and a trans-2,3-cyclic carbonate on the terminal glucose (7). Inulin carbonates have utility in the insolubilizaton of biologically active molecules such as enzymes or immunoglobulins. 

Inulin etherification products have utility in cosmetics or pharmaceuticals as carriers for water-insoluble substances or to stabilize aqueous solutions of compounds with low water solubility. They may also be used as emulsifiers or as an additive in textiles and paper and as softeners of thermoplastic polymers (Kunz and Begli, 1995). 

Inulin alkoxylates are reported to have surface-active, emulgating, and stabilizing properties. They may also be further altered via reaction with other epoxides. Initial synthesis methods utilized... 

Fuchs, A., Potentials for non-food utilization of fructose and inulin, Starch/Starke, 39, 335-343, 1987. 

Fuchs, A., Production and utilization of inulin Part II. Utilization of inulin, in Science and Technology of Fructans, Suzuki, M. and Chatterton, N.J., Eds., CRC Press, Boca Raton, FL, 1993, pp. 319-351. 

Economic data for the production and utilization of Jerusalem artichoke are relatively scarce, because the crop is not currently grown on a large commercial scale. However, there are some economic analyses for crop production and the use of Jerusalem artichoke for bioethanol and inulin production that highlight its potential. Bioethanol is in demand as a gasoline additive and biofuel, while inulin is increasingly used as a food ingredient. The tops and tubers of Jerusalem artichoke also have many other potential applications. 

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