Inulin carbonates

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. 

Butenediol Succinic acid Lactic acid Inulin esters O-Succinoylated inulin Methylated inulin Inulin carbonates 0-(Carboxymethyl)inulin Inulin ethers Dialdehyde inulin Inulin carbamates Inulin-amino acids 0-(Cyanoethyl)inulin... 

Preparation of Inulin. Comminute the tubers or roots in a food chopper or similar appliance and express the juice with a tincture press, using, if necessary, a small portion of water to complete the extraction. Heat the juice to 60-70° and add milk of lime to about pH 8. Filter and adjust the pH to 7 with oxalic acid. Heat to 70-80°, add activated carbon and filter. Allow the filtrate to stand quiescent overnight, during which time the inulin separates in the form of small spheroids. The yield may be increased by freezing the solution and allowing it to thaw at a low temperature. Filter and wash the inulin with abundant quantities of cold water. 

The moist cake of inulin has at this point a dry substance content of 35-40%. It can be purified by dissolving in hot water to a concentration of about 15-18%, treating with carbon, filtering, and allowing to separate again by chilling. 

A procedure that is described by Tollens and Eisner4 is probably suitable for materials less pure than fresh dahlia juices. The juice is expressed in the presence of calcium carbonate, fermented at 25° with baker s yeast, defecated with lead acetate and filtered. After removal of the excess lead with hydrogen sulfide, the filtrate is frozen and thawed to cause the separation of inulin. 

If heated in glycerol,7-9 or ethylene glycol, or even in water solution and precipitated from these solutions by alcohol, inulin separates in a form soluble in cold water. This soluble form is also produced by the action of carbon dioxide.10... 

Inulin is therefore made up of D-fructofuranose residues joined through carbons 1 and 2. The properties of inulin point to a symmetrical arrangement and hence carbon 2 of each D-fructose residue is joined to carbon 1 of an adjacent one. 

There are several examples of one-pot reactions with bifunctional catalysts. Thus, using a bifunctional Ru/HY catalyst, water solutions of corn starch (25 wt.%) have been hydrolyzed on acidic sites of the Y-type zeolite, and glucose formed transiently was hydrogenated on ruthenium to a mixture of sorbitol (96%), mannitol (1%), and xylitol (2%) [68]. Similarly a one-pot process for the hydrolysis and hydrogenation of inulin to sorbitol and mannitol has been achieved with Ru/C catalysts where the carbon support was preoxidized to generate acidic sites [69]. Ribeiro and Schuchardt [70] have succeeded in converting fructose into furan-2,5-dicarboxylic acid with 99% selectivity at 72% conversion in a one-pot reaction... 

By far the highest industrial potential for a fructose-based compound is to be attributed to HMF, which has been termed a key substance between carbohydrate chemistry and mineral-oil-based industrial organic chemistry. Like the bulk-scale commodities hexamethylenediamine and adipic acid, HMF represents a six-carbon compound with broad industrial application profiles. It is readily accessible from fructose or inulin hydrolysates by acid-induced elimination of three... 

Inulin nitrate is insol in w, eth, ethyl and methyl ale, toluene and carbon tetrachloride, but dissolves in acetone, ether ale mixt, coned H2S04, ethyl acetate etc. It does not crystallize from solutions but forms a film... 

Fuller s earth (hydrated aluminosilicate) Magnesium oxide Charcoal Alumina Magnesium trisilicate Silica gel Calcium hydroxide Magnesium carbonate Calcium phosphate Calcium carbonate Sodium carbonate Talc Inulin Sucrose = starch Petroleum ether, b 40-60°- Petroleum ether, b 60-80°. Carbon tetrachloride. Cyclohexane. Benzene. Ethyl ether. Chloroform. Ethyl acetate. Acetone. Ethanol. Methanol. Pyridine. Acetic acid. 

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. 

In addition to its limited role as a storage form of carbon, inulin is thought to be more widely involved in membrane protection during dehydration of many species (Vereyken et al 2003). The interaction of inulin with membrane lipids in a model system was found to be chain length dependent. Inulin-type fructans had a more pronounced interaction with the membrane lipids than... 

Inulin can be modified to compounds that display good heavy metal complexing properties similar to ethylene diamine tetra-acetic acid (EDTA) but with better biodegradation properties (Bogaert et al., 1998). Inulin is first oxidized using sodium periodate to the dialdehyde, and then reduced to a polyol using Pt/C and hydrogen. The polyol can then be modified with carbon disulfide to form xanthate or with S03-pyridine to obtain an inulin sulfate. Alternatively, the dialdehyde can be animated with diaminoethane and sodium cyanoborohydride and the product reacted with monochloroacetic acid sodium salt to form carboxymethylamino inulin. Each of these compounds can be used to precipitate heavy metals. 

Jarrell, H.C., Conway, T.F., Moyna, P., and Smith, I.C.P., Manifestation of anomeric form, ring structure, and linkage in the carbon-13 NMR spectra of oligomers and polymers containing D-fructose, maltulose, isomaltulose, sucrose, leucrose, 1-kestose, nystose, inulin, and grass levan, Carbohydrate Res., 76, 45-57, 1979. 

Ji, M., Wang, Q., and Ji, L., Method for Production of Inulin from Jerusalem Artichoke by Double Carbonic Acid Purification Process, Chinese Patent 1359957, 2002. 

Jerusalem artichoke is a plant with distinctive chemical properties. Inulin is stored as a reserve carbohydrate in the tubers, whereas starch is the storage form of carbon in most plants. Together with a low-fat and mineral-rich profile, inulin gives Jerusalem artichoke tubers their unique value in the human diet, in nutritional and medicinal products, and in animal feed. 

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