Fructans, which are beta-(2,1) and/or beta-(2,6) linked polymers of fructose, are important storage carbohydrates in many plants. They are mobilized via fructan exohydrolases (FEHs). The cloning, mapping, and functional analysis of the first 1-FEH (EC 3.2.1.153) from Lolium perenne L. var. Bravo is described here. By screening a perennial ryegrass cDNA library, a 1-FEH cDNA named Lp1-FEHa was c...

Plant cell wall invertases and fructan exohydrolases (FEHs) are very closely related enzymes at the molecular and structural level (family 32 of glycoside hydrolases) but they are functionally different and are believed to fulfill distinct roles in plants. Invertases preferentially hydrolyze the Glc-Fru linkage in sucrose while plant FEHs have no invertase activity and only split terminal Fru-F...

Nondigestible but fermentable dietary fructans such as oligofructose exert many effects on gut physiology through their fermentation end products such as short-chain fatty acids. Could other metabolites be produced in the gut and contribute to the physiologic effects of dietary fructans? The aim of the study was to evaluate the influence of oligofructose on putrescine, spermidine and spermine c...

AIMS This study was carried out to evaluate in vitro the fermentation properties and the potential prebiotic activity of Agave-fructans extracted from Agave tequilana (Predilife). METHODS AND RESULTS Five different commercial prebiotics were compared using 24-h pH-controlled anaerobic batch cultures inoculated with human faecal slurries. Measurement of prebiotic efficacy was obtained by compa...

High molecular weight fructans are the main class of water-soluble carbohydrate used for energy storage in many temperate grass species including perennial ryegrass (Lolium perenne L.). As well as being important readily mobilisable energy reserves for the plant, fructans are also involved in stress tolerance. Fructans are also readily digested by grazing ruminants and hence are a valuable sour...

The role of fructans from leaf sheaths for the refoliation of Lolium perenne after severe defoliation was assessed by following the fate of (13)C-fructose supplied to leaf sheaths at the time of defoliation. At the end of the 4 h labelling period on defoliated plants, 77% of the (13)C incorporated was still located in leaf sheaths. Only 4% and 0.9% were, respectively, allocated to stem and root...

AIMS We assessed to what extent fructans of different degrees of polymerization (DP) differ in their prebiotic effectiveness towards in vitro microbial communities from the proximal and distal colon. METHODS AND RESULTS Two short chain fructans - oligofructose (DP 2-20) and inulin (DP 3-60) - were administered to the Simulator of the Human Intestinal Microbial Ecosystem (SHIME) at 2.5 g day(-...

Fructans are fructose-based oligo-and polysaccharides of natural origin. Fructan and fructose species are sometimes confused by the great public, although they clearly have different biochemical and physiological properties. This review discusses aspects of the use of fructose and fructans in foods in the context of human health, with possible differential effects on cellular autophagy in cells...