Plant inulin

A substance that fulfills these criteria is inulin, a polysaccharide found in plants. Inulin is administered intravenously to a patient at a rate that results in a constant plasma concentration over the course of at least 1 h. The urine is collected and its volume and concentration of inulin are measured. 

Polymers of D-fructose are important carbohydrate reserves in a number of plants. Inulins and levans are two major types that differ in structure. D-Fructans require only relatively mild conditions for their hydrolysis, for example, levan was qualitatively hydrolyzed by hot, dilute, aqueous oxalic acid. Permethylated fructans could be hydrolyzed with 2 M CF3CO2H for 30 min at 60°. Fructan oligosaccharides were hydrolyzed in dilute sulfuric acid (pH 2) at 70 (see Ref. 53) or 95° (0.1 M). D-Fructans from timothy haplocorm (where they comprise 63% of the water-soluble carbohydrates) could be hydrolyzed with 0.01 M hydrochloric acid at 98°. 

Fructans are polysaccharides composed of o-fructofuranose units. They are important in short-term energy reserves for grasses and some plants. Inulin, found in dahlias, and levans from grasses are examples of fructans. Levans are short linear polysaccharides composed of (3 2 1 linked fructose units as illustrated in structure 9.21. 

Vogel, M., Preparation of hydrogenated fructooligosaccharides from long-chain plant inulin, in Proceedings of the 6th Seminar on Inulin, Fuchs, A., Schittenhelm, S., and Frese, L., Eds., Carbohydrate Research Foundation, The Hague, 1996, pp. 81-84. 

Inulin is characterized by a p-(2—>1) linked backbone and is generally found as reserve carbohydrate in plants such as chicory (up to 20%), Jerusalem artichoke, and onion, and also in some bacteria. Plant inulin has a degree of polymerization (DP) with a maximum up to 200, which depends on the plant species and their life-cycle. Bacterial inulin has a much higher DP (from 10,000 to more than 1(X),000) but is also highly branched (>15%). Both DP and the presence of branches are important properties since they influence the functionality of the inulin. Many possible applications demand a high molecular weight inulin like bacterial inulin, but without branches. 

This obvious structural difference between plant and bacterial inulin has its origin in the individual synthesis related system. Feedstock for both inulins is sucrose. However, the plant inulin production is a two-step reaction, starting with a sucrose-1-fructosyltransferase (1-SST). One sucrose molecule acts as donor and a second one as acceptor of a fructosyl unit. This leads to the formation of the trisaccharide 1-kestose. Catalyzed by a fructan-fructan-1-fructosyltransferase (1-FFT), fructosyl units are shuffled between the 1-kestose and higher polymeric p-(2 1) linked fructan molecules in the second step. Repetition of this step results in inulin with (3-(2 1) linkages only [129-132]. 

Bacterial and plant inulin are different not only in molecular weight and in the degree of branching but also in the synthesis and the enzymes applied. Both inulins are synthesized via sucrose. Glucose is generated as by-product. 

This fructosyltransferase and the related fructan is interesting for many possible applications. Only based on sucrose as raw material high molecular weight inulin, preferably without branches similar to plant inulin, can be produced in aqueous solution. Scale-up is the same as the production design for dextran or neo-amylose. The utilization of the simultaneously formed glucose as food, feed or fermentation medium should be no problem. 

Inulin is an energy storage polysaccharide in some plants. Inulin consists offructose units linked beta(2-l). It is found in onions, garlic, jicama, agave, and chicory. Plants that synthesize inulin typically do not make starch. 

In nature, fmctose (levulose, fmit sugar) is the main sugar in many fmits and vegetables. Honey contains ca 50 wt % fmctose on a dry basis. Sucrose is composed of one unit each of fmctose and dextrose combined to form the disaccharide. Fmctose exists in polymeric form as inulin in plants such as Jemsalem artichokes, chicory, dahlias, and dandeHons, and is Hberated by treatment with acid or enzyme. 

Degree of polymerization distribution of a plant fructan (inulin) at increasing physiological age of the source remarkable performance of S-200 in the low dp range degree of polymerization distribution obtained from bad (P-6) and good (S-200 / P-6) resolution of high dp components... 

It is not proposed to include the better known polysaccharides or the plant gums in the group because they can be conveniently classified separately. It must be pointed out, however, that some of these may occur naturally in firm combination with protein as instanced by the shock effect observed when solutions of crude inulin are injected into animals and by the reported isolation of desmoglycogen4 and glycogen combined with myosin.6... 

Phosphoric acid esters of the ketopentose D-ribulose (2) are intermediates in the pentose phosphate pathway (see p.l52) and in photosynthesis (see p.l28). The most widely distributed of the ketohexoses is D-fructose. In free form, it is present in fruit juices and in honey. Bound fructose is found in sucrose (B) and plant polysaccharides (e.g., inulin). 

The starches, the most important vegetable reserve carbohydrate and polysaccharides from plant cell walls, are discussed in greater detail on the following page. Inulin, a fructose polymer, is used as a starch substitute in diabetics dietary products (see p.l60). In addition, it serves as a test substance for measuring renal clearance (see p.322). 

Figure 14.6. Crystals formed in plant cells, (a) Calcium oxalate in begonias, (b) Inuline in dahlias.

Calendula officinalis L. Jin Tsan Jiu (Marigold) (whole plant) Arnidiol, carotenes, calenduline, cerylalcohol, flavoxanthin, lycopene, oleanolic acid, inulin, rebixanthin, violaxanthin. tocopherol, salicylic acid.50 Treat bleeding gums, bleeding piles, for amenorrhea, bruises, cholera, cramps, eruption, fevers, flu. 

In 1903, M. Tswett first applied adsorption chromatography to the separation of plant pigments, using a hydrocarbon solvent and inulin powder (a carbohydrate) as stationary phase. The separation of colored bands led to the name chromatography, from the Greek word chromatos, meaning color." Tswett later found that CaC03 or sucrose also could be used as stationary phases.3... 

The concepts thus obtained touch on the phenomenon of assimilation. Fischer wrote in 1890 Chemical synthesis leads... to optically inactive acrose. In contrast to this, only active sugars have so far been found in plants. No known fact contradicts the supposition that the plant produces. . . first the inactive sugars which it then resolves, and uses the members of the d-mannitol series to build up starch, cellulose, inulin, and the like, while using their optical isomers for other purposes, now unknown.. . . Since then, I have attempted in vain to find Z-glucose or... 

The polysaccharide inulin is an energy-storage substance found in the tubers of a number of plants. 

Trautwein, E.A., Rieckhoff, D., and Erbersdobler, H.F. 1998. Dietary inulin lowers plasma cholesterol and triacylglycerol and alters biliary bile acid profile in hamsters. J. Nutr. 128, 1937-1943. Trautwein, E.A., Duchateau, G. S. M. J.E., Lin, Y., Molhuizen, S.M., Mel nikov, H. O. F., and Ntanios, F.Y. 2003. Proposed mechanisms of cholesterol lowering action of plant sterols. Eur. 

Terrestrial plants Starch, cellulose, inulin guar, karaya, pectin... 

Compounds with different structures but with the same therapeutic activity isolated from different plant species act as active moieties for the treatment of particular diseases. Some of these compounds have been abandoned due to toxicity but these compounds apparently do not cause serious adverse effects. Some of these active principles originate from edible plants and their inclusion in the diet would undoubtedly be of some value because of their hypocholesterolemic potential. Several phytoconstituents including inulin, pectin, gugglu lipids, flavonoids, ginkoloids, saponins, tannins, and others obtained from various plant sources have proven hypolipidemic potentials as has been further explained in Tables I and II. The chemical structures of a few potential phytoconstituents with hypolipidemic activity are shown in Figure 2. It is hoped that as new additions are made to the list of these active compounds causing only minimum untoward side effects, these naturally... 

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. 

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