Fructans metabolism

Little information is available on the specific control of fructan metabolism in higher plants73 or in microorganisms.35 If a regulatory role is envisaged for the di-D-fructose dianhydride enzymes, as has been suggested for microorganisms,71 then more detailed studies are required. 

Darwen, C.W.E. and John, P., Localization of the enzymes of fructan metabolism in vacuoles isolated by a mechanical method from tubers of Jerusalem artichoke Helianthus tuberosus L.), Plant Physiol., 89, 58-663, 1989. 

Frehner, M., Keller, F., and Wiemken, A., Localisation of fructan metabolism in the vacuoles isolated from protoplasts of Jerusalem artichoke tubers Helianthus tuberosus L.), J. Plant Physiol., 116, 197-208, 1984. 

Fructans are oligomers and polymers formed by polymerizing fructose from transport metabolite sucrose on one out of three possible starter trioses 1-kestose yields inulin-type (2 1)-p-D-fructans, 6-kestose yields levan-type (2 6)-p-D-fructans (Fig. 3A), and neo-kes-tose yields mixcD-type and/or branched (2 1), (2 6)-p-D-fructans (Fig. 3C). Pronounced fructan metabolism is found in composites (chicory, Jerusalem artichoke), Liliaceae (onion, chives, garlic), cereals (wheat, barley, rye, oat), Asparagaceae (asparagus), Amaryllidaceae (banana), and Agavaceae (agave). 

Beylot, M. 2005. Effects of inulin-type fructans on lipid metabolism in man and in animal models. Br. J. Nutr. 93(Suppl. 1), S163-S168. 

Filipiak-Florkiewicz, A., Effect of fructans on hardness of wheat/rye bread crumbs, Zywienie Czlowieka i Metabolism, 30, 978-982, 2003. 

Pollock, C.J., Fructans and the metabolism of sucrose in vascular plants, New Phytol. 104, 1-24, 1986. 

Only a few days before his death, Percival took a prominent part in a conference on grass, sponsored by the Nutrition Society, at which he read a paper on the Carbohydrate Constituents of Herbage. In this paper, he emphasized the importance of the fructans as reserve carbohydrates in the metabolism of the plant, and expressed the opinion that they would be found to play a considerable part in the chemistry of the preservation of grass in the form of silage. 

Information on the metabolism of D-fructans is derived mainly from examination of inulin. Sucrose-sucrose 1-fructosyltransferase (SST) and transfructosylase (FFT) are responsible for the synthesis of D-fructans, whereas hydrolases A and B are involved in their breakdown. 

Particular difficulties exist, however, in purifying dextrans synthesized by many streptococci, because the bacteria simultaneously elaborate exocellular fructans (levansDextrans and levans synthesized concomitantly by Leuconostoc micro-organisms have been separated by fractionally precipitating the polysaccharides from aqueous ethanol. These separative procedures are, however, only effective when considerable differences in molecular weight exist between the main fractions of the two polysaccharides, and, as a result, they are of limited value in effecting separation of levans from many streptococcal dextrans. Reports that some oral bacteria are able to metabolize levans suggest that... 

A fructan. See Fructans, F-43. Formed by the action of various enzymes on sucrose. Also obt. from some monocotyledons and from moulds, e.g. Aspergillus. Isol from the roots of asparagus. Appears to play an essential role in the metabolism of D-fructose polymers in the tubers of the Jerusalem artichoke. 

Cani PD, Delzenne NM. The role of the gut microbiota in energy metabolism and metabolic disease. Curr Pharm Des. 2009 15 1546-1558. Pool-Zobel BL. Inulin-type fructans and reduction in colon cancer risk review of experimental and human data. Br J Nutr. 2005 93 (suppl.l) S73-S90. 

Demigne, C., Jacobs, H., Moundras, C., Davicco, M.J., Horcajada, M.N., Bernalier, A., and Cox-am, V. 2008. Comparison of native or reformulated chicory fructans, or non-purified chicory, on rat cecal fermentation and mineral metabolism. EurJNutr 47(7), 366-1 A. 

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