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The Journal of Nutrition Vol. 128 No. 1 January 1998,
pp. 11-19
, and
* Unité de Biochimie Toxicologique et Cancérologique, Department of Pharmaceutical Sciences, Université Catholique de Louvain, B1200 Brussels, Belgium; ORAFTI, B3300 Tienen, Belgium; and ** Microbiology Department, Institute of Food Research, Reading Laboratory, Earley Gate, Reading, U.K.
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ABSTRACT |
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Abstract
Introduction
References
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Research data on the bifidogenic effect of 
(2-1)fructans, which at present are commercialized in the U.S., Japan and Europe as food ingredients, are presented. These food ingredients originate from two different sources. Short-chain fructo-oligosaccharides are synthesized from sucrose and are composed of GFn [n (2-1) linked fructose moieties bound to a glucose molecule; 2 
n 4]. The longer chain length molecule inulin is extracted with hot water from chicory roots (Cichorium intybus) and is also composed of GFn molecules (with 2 < n < 60). Oligofructose is a partial hydrolysate of inulin and is composed of GFn and Fm molecules (n and m indicate the number of fructose moieties with 2 n, m 7). All types of (2-1)fructans are well fermented by intestinal bacteria. For a given chain length, there is no difference in fermentation rate between GFn- and Fm-type -fructans. In vitro fermentation of inulin revealed that molecules with a chain length (degree of polymerization or DP) > 10 are fermented on average half as quickly as molecules with a DP < 10. All (2
1)fructans are bifidogenic and classified as biobiotics.
Dietary carbohydrates that have escaped digestion in the upper gastrointestinal tract form the predominant substrates for bacterial growth in the colon. There is also a (lesser) contribution from proteins and amino acids, as well as endogenously produced carbohydrates and glycoproteins. Resistant starch is not hydrolyzed by pancreatic amylases but can be metabolized by bacterially produced enzymes, e.g., from saccharolytic clostridia, bacteroides and bifidobacteria. Non-starch polysaccharides, such as celluloses, hemicelluloses, pectins and gums, may also be fermented in the large gut. Other sugars such as lactose, raffinose and stachyose and certain sugar alcohols, like sorbitol and xylitol, also contribute to the fermentable carbohydrate load (Cummings and Englyst 1995 An oligosaccharide is characterized by number, type and sequence of its monosaccharide moieties. On average, up to 10 monomeric units are contained in the chain, which may be either linear or branched. Oligosaccharides that are not hydrolyzed by digestive enzymes in the upper gastrointestinal tract are non-digestible and therefore reach the colon intact.
Non-digestible oligosaccharides include those that contain fructose, glucose, xylose and galactose (Delzenne and Roberfroid 1994 Among these, fructans extracted from the root of Cichorium intybus (chicory) have been authorized as food ingredients in all European countries as well as in the U.S., Canada and Japan. Similar products obtained by an enzymatic synthesis via transfer of fructosyl units from sucrose molecules are widely used in the Japanese food industry where they have been ascribed various functional properties (Bornet 1994 The nutritional and biological properties of these food ingredients include dietary fiber effects, selective stimulation of the growth of bifidobacteria in the colon, systemic modulation of lipid metabolism and future potential as low energy sugar or fat substitutes (Gibson et al. 1994 Because of the potential health-promoting properties of certain food components, we have recently introduced the concept of prebiotics (Gibson and Roberfroid 1995 Any food ingredient that enters the large intestine is a candidate prebiotic. However, to be effective, selective fermentation by the colonic microbiota is crucial. This has been demonstrated with non-digestible oligosaccharides (especially those that contain fructose). Bifidobacteria have been identified as preferred target microorganisms for prebiotics (Gibson et al. 1995
Chicory-derived fructans, i.e., inulin and its hydrolysate, oligofructose, are prebiotics that may also be classified as functional food ingredients. This classification requires a strict scientific approach, whose strategy implies the identification as well as an understanding of the mechanisms of interactions between the food ingredient and particular physiologic functions. This should also be followed by a demonstration of any such interaction. Although the difference between functionality and health promotion is large and should be distinguished, the approach may also lead to certain health claims (Roberfroid 1995 In this review, available data that confirm the ability of chicory inulin and oligofructose to specifically stimulate the growth of bifidobacteria in the human colonic microbiota will be summarized and compared. Throughout, the term chicory fructo-oligosaccharides will be used to refer to both inulin and the products of its partial enzymatic hydrolysis, whereas the term synthetic fructo-oligosaccharides will be used for those products obtained by enzymatic synthesis from sucrose.
Chicory inulin and its enzymatic hydrolysis products are mixtures of
In vitro experiments on the comparative fermentation of chicory inulin and oligofructose in anaerobic batch culture fermenters inoculated with 100 g/L mixed human fecal bacteria and 7 g/L of the substrate have been conducted (Gibson and Wang 1994a In vitro fermentations of chicory fructo-oligosaccharides by human colonic bacteria, mainly bifidobacteria, produce lactate and short-chain carboxylic acids (mostly acetate). Consequently, the bacterial metabolism of these substrates causes a marked decrease in the culture medium pH. Batch culture experiments have been conducted, using pure cultures of different bacterial species, incubated for 96 h in the presence of 5 g/L substrate (Wada 1990
The in vitro profiles of bacterial fermentative activities on certain growth substrates give the potential for such events in vivo. For example, a preferred fermentation by bifidobacteria may be of some benefit to the host if the purported beneficial aspects associated with these microorganisms are reflected in a natural habitat, such as the human large intestine. The in vivo potential requires confirmation, however.
Both chicory inulin and its hydrolysis product, oligofructose, have been used in human volunteer studies. In the studies reported by Gibson et al. (1995)
From the information given in this review, the following facts can be emphasized: 1) Chicory fructo-oligosaccharides are a group of at least two food ingredients, i.e., oligofructose, which is composed of GFn and Fm oligomers with a DP ranging from 2 to 7, and an average DP of approximately 4 to 5, and inulin, which is composed almost exclusively of GFn molecules with a DP ranging between 2 and 60, and an average DP of 10. 2) All chicory fructo-oligosaccharides are rapidly and completely metabolized when incubated in the presence of anaerobic batch cultures of human fecal bacteria. The GFn and Fm oligomers are metabolized at similar rates. The fermentation, however, is slower for DP >10. 3) The metabolism of chicory fructo-oligosaccharides in human fecal slurries is accompanied by a progressive fall in the pH of the culture medium (~1.5 pH unit after 12 h), which may indicate fermentation by bifidobacteria. Growth of pure cultures of various bifidobacterial species is well promoted by both inulin and oligofructose. When other bacterial genera are considered, it appears that only a small proportion are able to grow on fructo-oligosaccharides. 4) Bifidobacteria grow faster than other intestinal bacteria on chicory fructo-oligosaccharide, and this is confirmed by in vivo experiments. In vivo human studies also suggest that the log increase in the number of bifidobacteria depends more on the initial number of bifidobacteria, irrespective of the dose of the fructo-oligosaccharides.
Chicory inulin and its partial enzymatic hydrolysate oligofructose selectively promote the growth of bifidobacteria in the human gut. The results presented here indicate that both GFn- and Fm-type molecules have a bifidogenic effect.
INTRODUCTION
Abstract
Introduction
References
). The metabolism of these carbohydrates produces a variety of products such as short-chain fatty acids (e.g., acetate, propionate and butyrate), gases (e.g., H2, H2S, CO2 and CH4), and organic acids (e.g., lactate, succinate and pyruvate). These products may have varying effects on host health. However, another form of dietary carbohydrate, oligosaccharides, is attracting increasing interest from the human health perspective (Cummings and Roberfroid 1997).
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Fig 2.
Time course of disappearance of 7 g/L chicory fructo-oligosaccharides from an anaerobic in vitro culture inoculated with mixed human fecal bacteria (100 g/L). Chromatographic analysis of the fructo-oligosaccharides was performed as previously reported (Van Loo et al. 1995 ). An aliquot of 5 g of medium was extracted with 2 mL hexane to remove fatty compounds. The sugars subsequently were silylated and analyzed by means of gas chromatography (Van Loo et al. 1995). Panels A and B represent the time course of disappearance of molecules with a degree of polymerization <10 and >10, respectively. Each point is the mean of 2-3 measurements.
).
).
, Roberfroid et al. 1993).
). A prebiotic is "a non-digestible food ingredient that beneficially affects the host by selectively stimulating the growth and/or activity of one or a limited number of bacteria in the colon, that can improve the host health." For a food ingredient to be classified as a prebiotic, it must meet the following criteria: 1) not be hydrolyzed or absorbed in the upper part of the gastrointestinal tract; 2) be a selective substrate for one or a limited number of potentially beneficial bacteria commensal to the colon, e.g., bifidobacteria and lactobacilli, which are stimulated to grow, and 3) be able, as a consequence, to alter the colonic microflora toward a potentially more healthy composition and/or activity.
). This is because bifidobacteria may exert a variety of effects that may contribute towards host health and comprise one of the dominant bacterial populations in the human large intestine.
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Fig 1.
Chemical structure of the various fructo oligosaccharides. G, glucose; F, fructose; n or m indicate the number of fructose moieties in the molecules.
and 1996).
THE CHEMICAL COMPOSITION OF CHICORY INULIN AND ITS HYDROLYSIS PRODUCTS
(2-1) linked fructans of the GFn and Fm types (Fig. 1). G refers to the glucosyl moiety, F to the fructosyl moiety and n or m indicates the number of fructosyl moieties (n ranges between 2 and 60 for chicory inulin and between 2 and 7 for chicory oligofructose). Inulin that is manufactured by ORAFTI (Tienen, Belgium) as Raftiline® ST (chicory inulin as it is present in the root) is obtained industrially by hot water extraction of fresh chicory roots (Gibson et al. 1994). It contains 92% fructo-oligosaccharides, almost exclusively (>98%) of the GFn type, with an average degree of polymerization (DP) of 10 hexose units. About 10% of the fructan chains have a DP ranging between 2 (F2) and 5 (GF4). Oligofructose (manufactured as Raftilose) is produced by partial enzymatic hydrolysis of native inulin and is a mixture of GFn- and Fm-type oligomers with an average DP of 4-5. It is available in different well-defined qualities and contains up to 90% Fm-type molecules. In the various preparations of oligofructose, oligomers with a DP from 2 (F2) up to 5 represent about 70% of the total fructo-oligosaccharides (Van Loo et al. 1995). The synthetic fructo-oligosaccharides (commercialized as Actilight, BMI, Paris, France) contain fructo-oligosaccharides of the GFn type, with an average DP of 3.7.
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Fig 3.
Relative rate of degradation of total and individual Fructosyln-Glucose (GFn) (panel A) and Fructosylm-1Fructose (Fm) (panel B) molecules in inulin hydrolysate (7 g/L) anaerobically incubated with human fecal slurry (100 g/L). There was no preference for either GFn or Fm as demonstrated by the relative overall rate of disappearance (panel C). Chromatographic analysis as described in Figure 2.
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Table 1.
Drop in culture pH due to fermentation of selected fructo-oligosaccharides by different bacterial species1,2
FERMENTATION OF CHICORY FRUCTO-OLIGOSACCHARIDES BY HUMAN FAECAL BACTERIA: CHEMICAL EVIDENCE
, Wang and Gibson 1993). Residual fructo-oligosaccharides were analyzed by means of gas chromatography (De Leenheer and Hoebregs 1994, Van Loo et al. 1995) at various time intervals after inoculation. Data reported in Figure 2 show that both inulin and oligofructose were rapidly and completely metabolized by the microbial flora in these fermenters. Moreover, the relative rate of fermentation was similar for both substrates. A more detailed analysis, however, revealed that the rate of degradation of oligomers with a DP <10 (Fig. 2a) was approximately twice that of molecules with a higher DP (Fig. 2b). The data presented in Figure 3 (a, b, c) demonstrate, moreover, that the GFn- and Fm-type components of inulin hydrolyzates disappeared from the culture media at a similar rate.
FERMENTATION OF CHICORY FRUCTO-OLIGOSACCHARIDES BY PURE CULTURES OF COLONIC BACTERIA AND MIXED POPULATIONS FROM FECAL SLURRIES: EFFECT OF FERMENTATION ON CULTURE MEDIUM pH
; Table 1). Data indicate that the utilization of oligofructose by Bacteroides spp., clostridia, enterococci, Klebsiellae, lactobacilli, Proteus and Staphylococcus was comparable to that of synthetic fructo-oligosaccharides but for both oligosaccharides, it was lower than that of glucose (P < 0.05). The utilization of inulin by the same bacterial species was also lower than that of glucose (P < 0.05), but it was also lower than that of the two other fructo-oligosaccharides except for Bacteroides spp., enterococci and staphylococci, incubated for 24 h in the presence of 7 g/L substrate (Fig. 4). When incubation was performed in the presence of various strains of bifidobacteria, data from Wang (1993) showed that the utilization of oligofructose was comparable to that of glucose and that inulin was also well fermented by all strains of bifidobacteria tested. Neither oligofructose nor inulin were to a significant extent fermented by Bifidobacterium bifidum. The only strain for which inulin appeared to be a less efficient substrate (0.7 pH units) than the lower DP oligomers (2.0 pH units) was Bifidobacterium animalis. When incubations were performed using human fecal bacteria as inoculum, both inulin and oligofructose were well fermented (Fig. 5). However, pH measurements after 6 and 12 h showed that the rate of inulin metabolism might be somewhat lower than that of oligofructose.
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Fig 4.
Drop in pH of the batch culture media inoculated with selected strains of bifidobacteria and incubated anaerobically for 24 h in the presence of 7 g/L glucose, oligofructose or inulin. Values are means of 3 determinations (SD 1%) and initial culture pH was 7.0 (adapted from Wang 1993).
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Fig 5.
Drop in pH as a function of time of the batch culture media inoculated with 100 g/L human fecal slurry and incubated anaerobically for 24 h in the presence of 7 g/L glucose, oligofructose or inulin at 37°C. Values are means ± SD from duplicate determinations from 6 different volunteers. Initial culture pH was 7.0 (adapted from Wang 1993 ).
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Fig 6.
Growth rate of various strains of bifidobacteria incubated anaerobically at 37°C in the presence of 10 g/L glucose, oligofructose or inulin. (*Significantly (P < 0.05) higher growth rate than rate on glucose). Results are means of 3 determinations and SD was always 10% (adapted from Wang 1993).
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Fig 7.
Changes in the numbers, expressed as multiplication factors (ratio CFUt=12 h/CFUt=0 h) of human fecal bacteria after the in vitro incubation for 12 h in the presence of 7 g/L fructose, starch, oligofructose or inulin (calculated values from Wang and Gibson 1993 ).
-D fructan-fructanohydrolase (EC 3.2.1.7) activity of the latter. Although pH change is a relatively poor indicator of bacterial growth, data reported in Table 1 indicate that bacteria other than bifidobacteria also are able to ferment fructo-oligosaccharides. These include Klebsiella pneumoniae, Staphylococcus aureus and epidermidis, Enterococcus faecalis and faecium, Bacteroides vulgatus, thetaiotaomicron, ovatus and fragilis, Lactobacillus acidophilus and Clostridium spp. (mainly Cl. butyricum).
IN VITRO FERMENTATION OF CHICORY FRUCTO-OLIGOSACCHARIDES: CONFIRMING THE BIFIDOGENIC EFFECT
reported that, after 12 h of incubation in the presence of 7 g/L fructose, starch, inulin or oligofructose, both of the chicory fructo-oligosaccharides had a relatively specific effect on growth of the bifidobacteria (Fig. 7).
showed that after six turnovers, chicory fructo-oligosaccharides, but not glucose, were able to selectively stimulate bifidobacterial growth; the number of these bacteria was almost three orders of magnitude higher than bacteroides. With glucose as substrate, bacteroides were two orders of magnitude higher than bifidobacteria (Table 2).
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Table 2.
Composition of the microflora of human fecal slurries (100 g/L) after six turnovers in single-stage continuous culture fermenters containing glucose, oligofructose
or inulin as the growth substrate (10 g/L)1
COLONIC FERMENTATION AND BIFIDOGENIC EFFECT OF CHICORY FRUCTO-OLIGOSACCHARIDES: HUMAN IN VIVO STUDIES.
, the subjects were maintained on strictly controlled diets to which the chicory fructo-oligosaccharides were added as supplements (15 g/d for 15 d, with sucrose as a control placebo). These studies showed that the intake of the chicory fructo-oligosaccharides significantly modified the composition of the fecal microbiota. The most marked effect was an increase in the number of bifidobacteria to the same extent and with the same statistical significance for both oligofructose and inulin. More particularly, in the oligofructose experiment, a significant (P < 0.05) reduction in bacteroides, fusobacteria and clostridia was observed (Figs. 8 and 9). The total number of bifidobacteria excreted in 24 h increased by five and eight times after feeding of oligofructose and inulin, respectively. In terms of the composition of the colonic microbiota, there was a major shift toward bifidobacteria, the latter becoming by far the most numerically predominant bacterial group during the chicory fructo-oligosaccharides feeding.
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Fig 8.
Changes in the predominant fecal bacterial groups of eight volunteers fed a strictly controlled diet for 45 d. The diets were supplemented with sucrose (d 0-15), oligofructose (d 16-30) and sucrose (d 31-45) (adapted from Gibson et al. 1995 ). The pies represent the relative percentage of the four major bacterial groups, with 100% as the sum of their individual counts. 
represents the differences in bacterial counts at the end of each feeding period.
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Fig 9.
Changes in the predominant fecal bacterial groups of four volunteers fed a strictly controlled diet for 30 d. The diets were supplemented with sucrose (d 0-15) and inulin (d 16-30) (adapted from Gibson et al. 1995 ). The pies represent the relative percentage of the four major bacterial groups, with 100% as the sum of their individual counts. represents the differences in bacterial counts at the end of each feeding period.
assessed the effects of prolonged ingestion in healthy humans of Bifidobacterium sp. fermented milk (BFM) with or without inulin (18 g/d) on fecal Bifidobacteria. They concluded that BFM substantially increased the proportion of bifidobacteria in the colonic flora, but the concurrent administration of inulin did not enhance the effect. More in-depth analysis of the data, however, revealed that 2 wk after stopping the consumption of the dairy products, the volunteers (n = 6) who received the inulin supplement had a significantly (P < 0.01) higher number of bifidobacteria compared with those receiving BFM (n = 6) only. However, the study took in consideration only the counts of bifidobacteria, and not those of other bacterial genera; as such, a selective bifidogenic effect cannot be confirmed. In addition, the bifidobacteria counts with BFM alone were very high, not leaving room for additional increase by inulin. The hypothesis tested in this study concerns a "synbiotic" (Gibson and Roberfroid 1995) rather than a prebiotic effect.
reported a study in which eight healthy volunteers were administered a controlled diet for 2 wk followed by 3 wk of a free diet. Both diets were supplemented with 8 g/d of chicory oligofructose containing 90% Fm molecules. At the end of the feeding periods, a significant increase in fecal bifidobacterial counts with a concomitant reduction in Bacteroides spp. was observed in comparison with the placebo period. This demonstrated that the Fm-type fructo-oligosaccharides have a bifidogenic potential similar to that of the GFn-type molecules.
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Table 3.
Summary of the published data showing an in vivo increase in the counts of bifidobacteria in human feces after consumption of various doses of synthetic fructo-oligosaccharides added to the usual diet
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Fig 10.
Correlation of the daily dose of (2-1) fructan initial bifidobacteria counts with the following respective subsequent increases in number of bifidobacteria: 1) The increase in counts of bifidobacteria (log10 of the ratio of the counts after and before the feeding period) in human feces is not correlated with the ingested dose (g/d) of chicory oligofructose or inulin and synthetic fructo-oligosaccharides. 2) The increase in counts of bifidobacteria (log10 of the ratio of the counts after and before the feeding period) in human feces is correlated with the initial number (log units) of these bacteria before the trial. Adapted from the human studies published by Gibson et al. (1995), Buddington (1994), Kleessen (1997) and Roberfroid (1997).
CONCLUSIONS
FINAL REMARKS
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FOOTNOTES |
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Manuscript received 20 February 1997. Initial reviews completed 25 April 1997. Revision accepted 2 September 1997.
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LITERATURE CITED |
|---|
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Abstract
Introduction
References
|
|---|
introducing the concept of prebiotics.
J. Nutr.
1995;
125:1401-1412
implications for health.
Int. Sugar J.
1994;
96:1150-1156 chicory fructo-oligosaccharides: a colonic food with prebiotic activity.
The World of Ingredients
1995;
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|
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|
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|
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 A. P. Femia, C. Luceri, P. Dolara, A. Giannini, A. Biggeri, M. Salvadori, Y. Clune, K. J. Collins, M. Paglierani, and G. Caderni Antitumorigenic activity of the prebiotic inulin enriched with oligofructose in combination with the probiotics Lactobacillus rhamnosus and Bifidobacterium lactis on azoxymethane-induced colon carcinogenesis in rats Carcinogenesis, November 1, 2002; 23(11): 1953 - 1960. [Abstract] [Full Text] [PDF]
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M. Verghese, D. R. Rao, C. B. Chawan, and L. Shackelford Dietary Inulin Suppresses Azoxymethane-Induced Preneoplastic Aberrant Crypt Foci in Mature Fisher 344 Rats J. Nutr., September 1, 2002; 132(9): 2804 - 2808. [Abstract] [Full Text] [PDF]
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 G Boehm, M Lidestri, P Casetta, J Jelinek, F Negretti, B Stahl, and A Marini Supplementation of a bovine milk formula with an oligosaccharide mixture increases counts of faecal bifidobacteria in preterm infants Arch. Dis. Child. Fetal Neonatal Ed., May 1, 2002; 86(3): F178 - F181. [Abstract] [Full Text] [PDF]
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K. K. Buddington, J. B. Donahoo, and R. K. Buddington Dietary Oligofructose and Inulin Protect Mice from Enteric and Systemic Pathogens and Tumor Inducers J. Nutr., March 1, 2002; 132(3): 472 - 477. [Abstract] [Full Text] [PDF]
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 A.J. McBAIN and G.T. MACFARLANE Modulation of genotoxic enzyme activities by non-digestible oligosaccharide metabolism in in-vitro human gut bacterial ecosystems J. Med. Microbiol., September 1, 2001; 50(9): 833 - 842. [Abstract] [Full Text] [PDF]
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W. Van den Ende, A. Michiels, D. Van Wonterghem, S. P. Clerens, J. De Roover, and A. J. Van Laere Defoliation Induces Fructan 1-Exohydrolase II in Witloof Chicory Roots. Cloning and Purification of Two Isoforms, Fructan 1-Exohydrolase IIa and Fructan 1-Exohydrolase IIb. Mass Fingerprint of the Fructan 1-Exohydrolase II Enzymes Plant Physiology, July 1, 2001; 126(3): 1186 - 1195. [Abstract] [Full Text] [PDF]
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M. B Roberfroid Prebiotics: preferential substrates for specific germs? Am. J. Clinical Nutrition, February 1, 2001; 73(2): 406S - 409. [Abstract] [Full Text] [PDF]
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K. E Scholz-Ahrens, G. Schaafsma, E. G. van den Heuvel, and J. Schrezenmeir Effects of prebiotics on mineral metabolism Am. J. Clinical Nutrition, February 1, 2001; 73(2): 459S - 464. [Abstract] [Full Text] [PDF]
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R. Hughes and I.R. Rowland Stimulation of apoptosis by two prebiotic chicory fructans in the rat colon Carcinogenesis, January 1, 2001; 22(1): 43 - 47. [Abstract] [Full Text] [PDF]
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H. Kaplan and R. W. Hutkins Fermentation of Fructooligosaccharides by Lactic Acid Bacteria and Bifidobacteria Appl. Envir. Microbiol., June 1, 2000; 66(6): 2682 - 2684. [Abstract] [Full Text]
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M. B Roberfroid Prebiotics and probiotics: are they functional foods? Am. J. Clinical Nutrition, June 1, 2000; 71(6): 1682S - 1687. [Abstract] [Full Text] [PDF]
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E. Menne and N. Guggenbuhl Fn-type Chicory Inulin Hydrolysate Has a Prebiotic Effect in Humans J. Nutr., May 1, 2000; 130(5): 1197 - 1199. [Abstract] [Full Text]
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M. B. Roberfroid Concepts in Functional Foods: The Case of Inulin and Oligofructose J. Nutr., July 1, 1999; 129(7): 1398 - 1398. [Abstract] [Full Text]
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K. R. Niness Inulin and Oligofructose: What Are They? J. Nutr., July 1, 1999; 129(7): 1402 - 1402. [Abstract] [Full Text]
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M. B. Roberfroid Caloric Value of Inulin and Oligofructose J. Nutr., July 1, 1999; 129(7): 1436 - 1436. [Abstract] [Full Text]
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J. O. Hunter, Q. Tuffnell, and A. J. Lee Controlled Trial of Oligofructose in the Management of Irritable Bowel Syndrome J. Nutr., July 1, 1999; 129(7): 1451 - 1451. [Abstract] [Full Text]
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