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Several pure cultures of alkaliphilic haloaloarchaea were enriched and isolated from hypersaline soda lakes in southwestern Siberia using amylopectin and fructans as substrates. Phylogenomic analysis placed the isolates into two distinct groups within the class Halobacteria. Four isolates forming group 1 were closely related to a recently described Natranaeroarchaeum sulfidigenes and the other three strains forming group 2 represent a novel genus-level phylogenetic lineage. All isolates are saccharolytic archaea growing with various starch-like alpha-glucans including soluble starch, amylopectin, dextrin, glycogen, pullulane and cyclodextrin. In addition, group 1 can use levan while group 2 – inulin (plant storage beta-fructans). Group 1 strains can also grow anaerobically with either glucose or maltose using elemental sulfur as the electron acceptor. Both groups are moderately alkaliphilic with a pH range for growth from 7.2 to 9.3 (optimum between 8.0–8.8) and low Mg-demanding extreme halophiles growing optimally at 4 M total Na+. The major respiratory menaquinone is MK-8:8 and the core biphytanyl lipids are dominated by archaeol (C20-C20) and a less abundant extended archaeol (C20-C25) with PG and PGP-Me as polar groups. The four isolates of group 1 are suggested to be classified into a new species as Natranaeroarchaeum aerophilus sp. nov. (type strain AArc-St1-1T = JCM 32519T = UQM 41458T). The three isolates of group 2 are proposed to form a new genus and species for which the name Natronocalculus amylovorans gen. nov., sp. nov. is suggested (type strain AArc-St2T = JCM 32475T = UQM 41459T)., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., BT/Environmental Biotechnology

[Background] The consumption of wheat/gluten is associated with adverse reactions for human health. Gluten and fructans are identified as the major compounds triggering and worsening adverse reactions to wheat, which are increasing, and as a consequence, avoidance of gluten/wheat is the common strategy of many individuals of the western population. Although bread is a product of daily consumption, there is a lack of information on the gluten and fructan contents and the influence of artisanal or industrial processes., [Objective] The aim of this study is to carry out a comparative characterization between artisan bakeries and hypermarkets in Spain for gluten and fructan contents in daily sold breads., [Design] A total of 48 types of bread highly consumed in Spain sold in artisan bakeries (long fermentation) and hypermarkets (short fermentations) were selected for comparing the gluten and fructan contents. Methods such as reverse phase-high performance liquid chromatography (RP-HPLC), R5 monoclonal antibody (moAb), and fructans protocols were used for the quantification of these compounds., [Results] Great variation for the content of gluten and fructans has been found between all bread categories. Although breads produced using long fermentation (artisan bakeries) contain significantly lower gluten, they have higher fructans than those using short fermentations (hypermarkets). Durum wheat breads had the lowest content of gluten. Moreover, spelt breads from artisan bakeries had the lowest content of fructans but not those from hypermarkets., [Discussion] In this study, we report the comparative characterizarion of the breads of the Spanish market. These food products presented variation in the amount of gluten and fructans, ligated in most of the cases to the nature of the providers: artisan bakeries against hypermarkets. Depending on the type of bread, the differences for the daily consumption of gluten and fructan can be 4.5 and 20 times, respectively., [Conclusions] We found strong differences for gluten and fructan contents among breads. These information may contribute to designing strategies to improve the management of gluten and fructans in bread.

Asparagus cultivation produces enormous amounts of biomass (leaves, stems, fruits, roots and rhizomes) that currently lacks of economic value at the time that implies an environmental challenge. From the bioeconomy point of view an added-value must be given to these co-products to shift their consideration from waste to chance. They are rich in phytochemicals, such as flavonoids, fructans and saponins, which can be easily extracted and purified by green and environmental friendly processes. Those bioactive extracts are of great interest for several industrial sectors. The exploitation of this biomass will represent an increase in the incomes of asparagus growers and life standard enhancement of rural areas.

Objective. To determine egg production in laying hens treated with oligofructose from agave. Materials and methods. Eighteen weeks old Hy-line W-36 hens (n = 300) were distributed randomly into 3 treatment groups: no feed supplementation (control) or feed supplementation with 0.1% of 0.2% oligofructose from agave (OFA). Hens were monitored from development until 30 weeks of egg laying. Results. A significant (p<0.05) increase in the percent of egg-laying hens as well as increased in egg weight and egg quality occurred in hens from the OFA treatment groups relative to the control hens. Significantly lower levels (p<0.05) of fecal putrescine were observed in hens from the OFA treatment groups. Conclusions. The oligofructose from agave may be used as an alternative feed additive in laying hens., RESUMEN Objetivo. Determinar la producción de huevos en gallinas tratadas con oligofructosa de agave (OFA). Materiales y métodos. Se utilizaron 300 gallinas de la línea genética Hy-line w-36, de 18 semanas de nacidas, distribuidas aleatoriamente en tres tratamientos con cuatro repeticiones de 25 gallinas cada uno. Los tratamientos consistieron en tres niveles de OFA, 0, 0.1 y 0.2% en alimento. La prueba duró desde las 18 hasta las 30 semanas de postura. Resultados. Se presentó un incremento significativo (p<0.05) en el porcentaje de postura y peso del huevo, así como en índices de calidad del huevo a favor de tratamientos con OFA. Se encontraron valores significativamente (p<0.05) más bajos de putrescina fecal en las gallinas tratadas con OFA. Conclusiones. El uso de la OFA en gallinas ponedoras puede ser una alternativa como aditivo en la alimentación.

Supplementing kindergarten children during a cold season with a prebiotic inulin-type fructans product with shorter and longer fructan chains has been shown to reduce febrile episodes requiring medical attention and to lower the incidence of sinusitis. These beneficial effects may be connected to the specific modulation of children’s gut microbiota. By applying quantitative and qualitative microbiota analysis this study aimed at characterising the gut microbiota composition and at exploring effects of prebiotic intervention on the gut microbiota during a 24-weeks intervention and during antibiotic treatment in healthy children. The study was a randomised, placebo-controlled trial with 258 healthy children aged 3 to 6 years consuming 6 g/day prebiotic inulin-type fructans or maltodextrin. During the course of the study, faecal samples were collected and subject to targeted qPCR analysis and phylogenetic profiling by multiplexed high throughput sequencing of the prokaryotic 16S rRNA gene PCR amplicons. The microbiota composition of the cohort could be clustered into three distinct constellations (enterotypes). Prebiotic intake resulted in a selective modulation of the gut microbiota composition. Relative abundance of Bifidobacterium was significantly higher in the prebiotic group (n=104) compared to control group (n=105) and this effect was found for all three enterotypes. Antibiotic administration decreased the relative abundance of Bifidobacterium in both groups. Nonetheless, children of the prebiotic group receiving antibiotic treatment displayed significantly higher levels of Bifidobacterium than children receiving the placebo control. Prebiotic supplementation induced specific changes in the gut microbiota composition of children aged 3 to 6 years. Moreover, it attenuated antibiotic-induced disturbances in the gut microbiota composition as shown by higher relative abundance of bifidobacteria at the end of the antibiotic treatment in the prebiotic group. With the

Inulin can improve the nutritional quality of gluten free (GF) bread and have a prebiotic activity. However, breadmaking might frustrate the enrichments efforts due to inulin loss. In this study we aimed at studying the inulin enrichment of GF bread. Two different yeasts [having normal (Y1) or reduced (Y2) invertase activity] were used to leaven the breads enriched with five marketed inulins, which differed for the degree of polymerization (DP) and the manufacturer. Inulin replaced 10% of the rice flour and had low, intermediate or high DP, which ranged from 2 to 20; ≈20; ≥20, respectively. Fructan hydrolysis occurred during leavening of Y1-GF breads, reaching losses up to 40% after baking, depending on the diverse DP of the inulin-forming fructans. Inulin loss was less relevant in Y2-GF breads (up to 5% after baking) than Y1-GF breads. Crumb texture was not negatively influenced by inulin presence, even if this was high (e.g., Y2-GF breads). Information collected within this study may provide further insight to better optimize a GF bread formulation in view of inulin enrichment.

Treatment with high CO atmospheres is effective in preventing strawberry decay and increasing firmness. Nevertheless, CO stress generates energy disturbances associated with a high rate of fermentation. This study was designed to measure the impact of high CO stress (3 d, 40 kPa CO) and its subsequent removal on fruit quality, osmotic balance and water relations. Fructo-trisaccharides isomers and raffinose were characterized and quantified by mass spectrometry (MS and MS). CO stress removal was marked by both a rapid upsurge in the ratio of unfreezable water to total water and an osmotic adjustment prompted by the accumulation of soluble sugars, 1-kestose, raffinose and galactinol. Due to strong increase in galactinol concentrations, we propose it as a suitable biomarker for fruit having undergone stresses associated with osmotic imbalance.

Many aspects are involved when processing a product, for instance, “yacón”. This product is a good example of how a product can be transformed for purposes of marketing and at the same time to know about its benefits for consumers. Yacon production is rising and it is encouraging people to find new forms of consumption, it is important to keep in mind that products like this are not regularly accepted in the common market. There are enough reasons to invest efforts into projects related to this raw material which clearly offers a variety of ways of consumption to people because of its low cost and constant supply, especially at harvest time because it offers clear alternatives when thinking about creating a company., El desarrollo de una práctica en la cual se involucran todos los aspectos que intervienen en la transformación de un producto, en éste caso el yacón, permite conocer de primera mano los tipos de transformación que pueden darse a un mismo producto para su comercialización y conocer de los beneficios en la salud de los consumidores. La producción de yacón se encuentra en ascenso e incentiva a buscar nuevas formas de consumo del tubérculo, sobre todo aquellas que por morfología no son aceptadas en el mercado común. Razón suficiente para poner empeño en proyectos relacionados con esta materia prima, que claramente ofrece gran variedad de formas de consumo y por su bajo costo y oferta permanente, especialmente en época de cosecha, ofrece alternativas claras para pensar en la creación de empresa.

Fructan molecules have a history of more than 150 years and ancient peoples used fructans containing plants as food, feed or medicine. The modern history of fructans began with their discovery by Rose (1804) and known at the turn of the 20th century considerable development with Edelman's proposal concerning their metabolism in higher plant. At present time, fructans are considered food not food ingredients, and are found in more than 500 food products resulting in significant daily consumption. Because the science of nutrition itself has changed, fructans are now considered as functional foods and the passionate history of their health benefits continues to arise interest of scientists. Contrary to the fact that non-digestible carbohydrates have been accused of causing an impairment in the small intestine absorption of minerals, research conducted during the last three decades demonstrated that fructans enhanced mineral absorption, and the scientific evidence claiming that fructans enhance mineral absorption is based on both animal and human experiments which are very conclusive. Although different hypotheses have been proposed to explain the roles of fructans in enhancing minerals absorption, the mechanisms behind this enhancement are still unclear, even though investigation have demonstrated that different fructans-related mechanisms may be involved in the increased absorption of minerals due to fructans intake. This review paper aims to report on the recent development and the roles of fructans in enhancing mineral absorption and their deficiencies prevention.

Inulin is a fructose polymer extracted from the root of industrial chicory (Cichorium intybus L.). The quality of the root extract is determined by the polymerization degree of inulin molecules and the free fructose concentration. Low autumnal temperatures trigger an inulin degradation phase which decreases the quality of the root extract. Therefore, the objective of this thesis was to understand the genetic determinism of the synthesis and the cold induced degradation of inulin. To do so, we evaluated the chicory genetic resources, conducted a candidate gene approach and a genome wide association study (GWAS). The assessment of the chicory genetic resources of the C.intybus germplasm confirmed the validity of the available classification, identified a new leaf cultivar subgroup and revealed a high genetic variability in most chicory groups. The candidate gene analysis investigated the associations between genetic polymorphisms in candidate genes involved in the inulin metabolism and the susceptibility to cold-induced inulin degradation. An indel in 1 FEH IIb was responsible for up to 35 % of the variance of traits describing the susceptibility to cold-induced inulin degradation, in a panel of 112 lines. A genome draft covering 85% of the chicory genome was created to map the SNPs identified by genotyping by sequencing in a panel of 366 lines, characterized by a very low linkage disequilibrium extent. The GWAS conducted on the panel identified, along with the 1 FEH IIb indel, new SNPs significantly associated to a small fraction of the variability of several traits describing the inulin and carbohydrates synthesis and the cold induced degradation of inulin. Therefore we concluded that the genetic determinism of inulin synthesis is multigenic and determined by several minor effect QTLs when cold induced inulin degradation result from the action of one major effect QTL and at least one minor effect QTL., (AGRO - Sciences agronomiques et ingénierie biologique) -- UCL, 2015

The development of efficient immobilized enzymes allows the separation of the biocatalysts from the reaction medium and their reuse, facilitating product recovery, and is usually accompanied by an enzyme stabilization effect. The selection of a proper carrier can be optimized by the combination of in silico analysis with experimental research. In this context, different immobilized biocatalysts have been described for the production of fructooligosaccharides (FOS). In this chapter we discuss several examples of immobilized FOS-producing biocatalysts developed in our laboratory. Fructosyltransferase from Aspergillus aculeatus was covalently attached to epoxy-activated polymethacrylate polymers (Sepabeads) and further applied to the synthesis of FOS in batch and continuous reactors. However, in order to obtain biocatalysts with higher operational stability, a simple modification of the calcium alginate enzyme entrapment technique was developed as an alternative to covalent methods. The resulting biocatalysts (Dried ALGinate Entrapped Enzymes, DALGEEs) do not re-swell in concentrated sugar solutions and exhibit high volumetric activity, operational stability (no loss of activity was observed during 700 h) and microbial resistance. For immobilization of levansucrase from Zymomonas mobilis, a prior cross-linking treatment with transglutaminase allowed to improve the operational stability probably due to a lower enzyme leakage throughout the pores., The book Food Oligosaccharides: Production, Analysis and Bioactivityis a comprehensive reference on the naturally occurring and synthesised oligosaccharides, which will enable food professionals to select and use these components in their products. It is divided into three sections: (i) Production and bioactivity of oligosaccharides, (ii) Analysis and (iii) Prebiotics in Food Formulation. The book addresses classical and advanced techniques to structurally characterize and quantitatively analyse food bioactive oligosaccharides. It also looks at practical issues faced by food industry professionals seeking to incorporate prebiotic oligosaccharides into food products, including the effects of processing on prebiotic bioavailability. This book is essential reading for food researchers and professionals, nutritionists and product developers working in the food industry, and students of Food Science with an interest in functional foods.

The typical Serbian diet is characterised by high intake of cereal products and also legumes are often used. The content of total fibre as well as certain fibre fractions was determined in cereals, cereal products, and cooked legumes. The content of total fibre in cooked cereals and cereal products ranged from 2.5 to 20.8 g/100 g, and in cooked legumes from 14.0 to 24.5 g/100 g (on dry matter basis). Distribution of analysed fibre fractions and their quantities differed significantly depending on food groups. Fructans and arabinoxylans were the most significant fibre fractions in rye flakes, and beta-glucan in oat flakes, cellulose and resistant starch were present in significant amounts in peas and kidney beans. When the size of regular food portions was taken into consideration, the best sources of total dietary fibre were peas and kidney beans (more than 11 g/serving). The same foods were the best sources of cellulose (4.98 and 3.56 g/serving) and resistant starch (3.90 and 2.83 g/serving). High intake of arabinoxylans and fructans could be accomplished with cooked wheat (3.20 g and 1.60 g/serving, respectively). Oat (1.39 g/serving) and barley flakes (1.30 g/serving) can be recommended as the best sources of beta-glucan.

Fructan is a polymer of fructose produced by plants and microorganisms. Within the plant kingdom about 45.000 species accumulate fructan as storage carbohydrate in addition to, or instead of, starch. Fructan accumulating species are mainly found in temperate and sub-tropical regions with seasonal or sporadic rainfall. During the last decades, the use of fructan in the (food) industry has rapidly evolved, because of its health promoting characteristics and interesting functional properties.Chicory (Cichorium intybus L.) is a biennial taproot-bearing crop plant that is grown for the production of inulin on an industrial scale. Inulin, a ß(2,1) linked linear fructan with a terminal glucose residue, is stored in the chicory taproots. The degree of polymerisation (DP) determines the application of the inulin and hence the value of the crop. This leads us to the central question of this thesis: What regulates the fructan yield and the degree of polymerisation, and how can we modify this? The DP is highly dependent on the field conditions and harvest time, and therefore the first step in answering this question was tostudy the regulation of fructan (inulin) metabolism throughout the growing season. This is described in Chapter 2. Metabolic aspects of inulin production and degradation in chicory were monitored in the field and under controlled conditions. We determined the concentrations of soluble carbohydrates, the inulin mean degree of polymerisation (mDP), inulin yield, gene expression and activity of enzymes involved in inulin metabolism in the taproots. Inulin biosynthesis - catalysed by sucrose: sucrose 1-fructosyltransferase (EC 2.4.1.99) (1-SST) and fructan: fructan 1-fructosyltransferase (EC 2.4.1.100) (1-FFT) - started at the onset of taproot development. Inulin yield increased with time following a sigmoid curve reaching a maximum in November. The maximum inulin mDP of 15 was reached in September and then gradually decreased. Based on the changes observed in the

La fléole des prés (Phleum pratense L.) est une Poacée fourragère pérenne caractéristique des régions tempérées et froides, utilisée pour l'alimentation animale en pâturage ou sous forme de foin ou d'ensilage. Elle accumule ses réserves glucidiques principalement sous forme de fructanes, polymères solubles de fructose, qui participent à la valeur nutritive du fourrage et au processus de fermentation lors de l'ensilage. Les objectifs de cette thèse étaient i) d'étudier le métabolisme des fructanes chez cette espèce pendant la croissance dans le but d'évaluer le stade de fauche permettant d'obtenir des teneurs maximales en fructanes, en prenant en compte le niveau de fertilisation azotée, ii) d'étudier le métabolisme des fructanes après la fauche, pendant le fanage et iii) d'identifier et caractériser les enzymes de dégradation des fructanes (les fructane exohydrolases, FEHs). Les tissus récoltés lors de la fauche (sommet des parties aériennes) ont été analysés pour quatre stades de développement (stade végétatif, montaison, épiaison et anthèse) et deux niveaux de nutrition azotée (0,375 et 3,75 mM de NH4NO3), en conditions hydroponiques. Le métabolisme de ces sucres a également été suivi après fauche, pendant le fanage, pour les deux derniers stades. Les résultats montrent que l'accumulation des fructanes est maximale à l'anthèse. La diminution des teneurs en NILN03 n'a pas d'effet sur l'accumulation des fructanes alors qu'elle provoque une forte augmentation de la concentration en amidon dans les limbes. Cela suggère que les mécanismes d'interactions entre le métabolisme de l'amidon et de l'azote d'une part, et le métabolisme des fructanes et de l'azote d'autre part sont différents. Pendant le fanage (à la lumière ou à l'obscurité, à 20°C ou l5°C), les teneurs en sucres solubles sont assez stables pendant les 24 premières heures tandis que les teneurs en protéines et en amidon diminuent puis se stabilisent dès que la matière sèche dépasse le seuil des 40%. L'activit

Onion (Allium cepa L.) waste disposal represents a worldwide environmental problem. A solution to this issue could be the use of onion waste as food-grade ingredients, which could be added to processed foods for their enrichment in bioactive compounds. For this purpose, onion waste should be adequately processed and stabilised. Thus, the objective of this work was to study the composition of processed onion waste, assessing the effects of processing and thermal stabilisation on onion waste bioactive compounds. Onion waste was triturated ('Paste') and triturated + pressed ('Bagasse', solid residue and 'Juice', liquid fraction). All by-products were stabilised by pasteurisation and sterilisation. Results indicated that bagasse was an enriched dietary fibre product (361-453 mg/g dry weight (DW)); paste showed high alkyl or alkenyl cystein sulphoxide (ACSO) content (5.6 mg/g DW); and juice showed large fructans concentration (205-221 mg/g DW). In paste and bagasse, pasteurisation and sterilisation improved soluble/insoluble fibre ratio, with no changes in total dietary fibre concentration in pasteurised products and a slight decrease (8 % on average) in the sterilised ones. In juice, thermal treatments produced fructans losses, more pronounced after sterilisation (59 % on average) than after pasteurisation (36 % on average). However, sterilisation provided by-products with better ACSO results than pasteurisation. As a conclusion, industrial processing has an important impact on the bioactive composition, generating products with different functional applications. Moreover, pasteurisation resulted to be the most suitable treatment to obtain safe products enriched in dietary fibre and fructans, while sterilisation could be used to produce products rich in ACSOs. © 2012 Springer Science+Business Media, LLC.

BACKGROUND: Metabolites released by the gut microbiota may influence host metabolism and immunity. We have tested the hypothesis that inulin-type fructans (ITF), by promoting microbial production of short-chain fatty acids (SCFA), influence cancer cell proliferation outside the gut. METHODS: Mice transplanted with Bcr-Abl-transfected BaF3 cells, received ITF in their drinking water. Gut microbiota was analysed by 16S rDNA polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) and qPCR. Serum Short-chain fatty acids were quantified by UHPLC-MS. Cell proliferation was evaluated in vivo, by molecular biology and histology, and in vitro. RESULTS: Inulin-type fructans treatment reduces hepatic BaF3 cell infiltration, lessens inflammation and increases portal propionate concentration. In vitro, propionate reduces BaF3 cell growth through a cAMP level-dependent pathway. Furthermore, the activation of free fatty acid receptor 2 (FFA2), a Gi/Gq-protein-coupled receptor also known as GPR43 and that binds propionate, lessens the proliferation of BaF3 and other human cancer cell lines. CONCLUSION: We show for the first time that the fermentation of nutrients such as ITF into propionate can counteract malignant cell proliferation in the liver tissue. Our results support the interest of FFA2 activation as a new strategy for cancer therapeutics. This study highlights the importance of research focusing on gut microbes-host interactions for managing systemic and severe diseases such as leukaemia.

To measure coronary band temperature (CBT) in healthy horses fed high-fructan or low-carbohydrate diets and to analyze the association of CBT with diet, time of day, and ambient temperature.

Recent data reported that inulin-type fructans extracted from chicory roots regulate appetite and lipid/glucose metabolism, namely, by promoting glucagon-like peptide-1 (GLP-1) production in the colon. The Agave genus growing in different regions of Mexico also contains important amounts of original fructans, with interesting nutritional and technological properties, but only few data report their physiological effect when added in the diet. Therefore, we decided to evaluate in parallel the effect of supplementation with 10 % agave or chicory fructans on glucose and lipid metabolism in mice. Male C57Bl/6J mice were fed a standard (STD) diet or diet supplemented with Raftilose P95 (RAF), fructans from Agave tequilana Gto. (TEQ) or fructans from Dasylirion spp. (DAS) for 5 weeks. The body weight gain and food intake in mice fed fructans-containing diets were significantly lower than the ones of mice fed the STD diet, TEQ leading to the lowest value. Serum glucose and cholesterol were similarly lower in all fructans-fed groups than in the STD group and correlated to body weight gain. Only RAF led to a significant decrease in serum TAG. As previously shown for RAF, the supplementation with agave fructans (TEQ and DAS) induced a higher concentration of GLP-1 and its precursor, proglucagon mRNA, in the different colonic segments, thus suggesting that fermentable fructans from different botanical origin and chemical structure are able to promote the production of satietogenic/incretin peptides in the lower part of the gut, with promising effects on glucose metabolism, body weight and fat mass development.

Cultivars of Lolium perenne with high concentrations of water soluble carbohydrates (WSCs) offer opportunities to mitigate greenhouse gas emissions (nitrous oxides) from grazed pastures and improve meat and milk production in livestock. Our previous studies demonstrated that fructan accumulation in the blades of high W SC grasses involves a strong gene x environment interaction. To identify the temperature effects on the expression of high sugar trait in the high sugar cultivars. we conducted a pot trial in climate chambers with temperature regimes set at10/10, 20/10 and 20/20°C (day/night), respectively. Water soluble carbohydrate concentrations, the expression of the key genes and proteins: l-SST (sucrose: sucrose l-fructosyltransferase), l-FFT (fructan: fructan l-fruclosyltransferase), 6G-FFT (fructan: fructan 6G-fructosyltransferase) and l-FEH l-fructan exohydrolases) involved in the fructan biosynthetic pathway of L. perenne were compared in blades and sheaths of three selected high sugar cultivars (P, A and H) and a common cultivar (F) grown under the three temperature regimes. We found that amongst the selected 3 high sugar cultivars, high molecular weight (HMW) WSC content was significantly higher in P and A cultivars, regardless of the temperature regimes. As expected, sheaths contained significantly higher concentrations of HMW WSCs (fructans) compared to leaf blades. The highest WSC contents in both leaf and sheath tissues accumulated at 10/10°C while the lowest accumulated at 20/20°C. Gene expression profiles demonstrated that all four genes studied were more significantly expressed in sheaths compared to blades, and the expression levels were highly correlated with fructan accumulation in this tissue. Low temperature resulted in significant up-regulation of l-SST in sheaths, but not in blades. l-FFT was highly expressed in blades of A and P cultivars. Unexpectedly. 6G-FFT was expressed more significantly in the control F cultivar. but not in the high su

De darmbarrière is een complex systeem dat het lichaam beschermt tegen schadelijke stoffen en pathogenen die met het voedsel binnenkomen. Om beter inzicht te krijgen in de biologische processen die zorgen voor de barrièrefunctie van darmcellen hebben we in een levend organisme, de rat, bestudeerd hoe deze reageren op twee verschillende stoffen die stress van de darmbarrière veroorzaken: het veel voorkomende voedselpathogeen Salmonella en het voedingsmiddel Fructo-oligosaccharides (FOS). Dit hebben we gedaan met zogenaamde whole genome transcriptoom (genexpressie) analyse, waarmee de activiteit van nagenoeg alle genen tegelijkertijd kwantitatief bepaald kan worden. Ons onderzoek is een van de eerste studies die de moleculaire effecten van een Salmonella infectie op darmcellen van een levend dier heeft onderzocht. Het bleek, tegen de verwachting in, dat Salmonella niet alleen een effect heeft op dunne darm cellen, maar ook op dikke darm cellen. Verder hebben we gevonden dat celkweek modellen, die tot nu toe veel gebruikt zijn voor infectieonderzoek , slechts in zeer geringe mate voorspellend zijn voor de effecten in het dier. Met de genexpressie analyse hebben we niet alleen nieuwe darmbarrière processen gevonden, maar ook nieuwe mogelijke biomarkers die gebruikt kunnen worden om de darmgezondheid te meten in interventie proeven met mensen of dieren. Een voeding met FOS verhoogt de doorlaatbaarheid van de darmwand en verergert de infectie met Salmonella. Dit ging gepaard met verhoogde expressie van genen die betrokken zijn bij de weerstand of afweer. Dit betekent dat verhoging van deze weerstand markers voorzichtig geïnterpreteerd moet worden en niet per definitie een gunstige situatie (verhoogde weerstand) weerspiegelt. Het heeft de voorkeur om weerstand markers altijd te koppelen aan meetbare en eenduidige eindpunten zoals passage van de bacteriën door de darmwand. Tenslotte hebben we sterke aanwijzingen verkregen dat een ontregeld energie metabolisme in darmcellen

Current recommendations for the management of obesity and type 2 diabetes include an increase in dietary fibres intake. Previous studies have demonstrated that specific fermentable dietary fibres (fructooligosaccharides: FOS) largely fermented in the caeco-colon may be promising nutrients in the control of the metabolic syndrome associated with obesity. The addition of one type of FOS, namely oligofructose (OFS), in the diet reduces body weight gain, decreases epidydimal adipose tissue mass in obese Zucker rats, and may lowers triglyceridaemia in rats and in humans. How do FOS, from a mechanistic point of view, exert their putative metabolic effects to control food intake, obesity and associated disorders? In that context, our work was devoted to analyse the putative modulation of gastrointestinal peptides (two anorexigenic peptides: GLP-1/PYY and one orexigenic peptide: ghrelin) involved in appetite, body weight regulation and glucose homeostasis. OFS significantly increased the concentration of GLP-1 in the portal plasma and in the proximal colon. Surprisingly, there were no modifications of PYY proteins or mRNA in the different intestinal segments. We observed that plasma ghrelin concentrations remained lower in OFS-fed than in control rats receiving a normal chow diet. Moreover, in another set of experiments performed in a model of hyperphagia linked to high-fat diet feeding, we shown that serum ghrelin concentrations, were equivalent in both groups during high-fat treatment, despite a lower food intake and body weight gain in rats receiving OFS in the high-fat diet. We reported that OFS improved glycaemia and plasma insulin, both in the post-prandial state and after an oral glucose load in diabetic rats. Moreover, the treatment with OFS allowed an improvement of pancreatic insulin and b-cell mass. Endogenous GLP-1 production was increased in OFS rats as compared to other diabetic rats. Therefore, we postulated that the beneficial effects of OFS could be linked, Thèse de doctorat en sciences biomédicales (nutrition et métabolisme) (SBIM 3) -- UCL, 2005

Festuca novae-zelandiae (Hack.) Cockayne is an endemic New Zealand perennial tussock forming grass of the family Poaceae. Morphologically F. novae-zelandiae exhibits a number of leaf adaptations associated with dehydration postponement as reflected in the climatic distribution of this species and its occurrence as a physiognomic dominant grass in semi arid short-tussock grasslands. Biochemical studies into the drought tolerance of this species have indicated the occurrence of tissue specific responses with respect to abscisic acid (ABA) and proline accumulation and protein turnover suggestive of a preferential protection of the tiller base and associated meristematic zones at the expense of lamina tissues. Further tissue specific biochemical responses to water-deficit stress in F. novae-zelandiae have been investigated. Changes in water-soluble carbohydrates (WSC) were monitoured over a 49-day dry-down period (decline in soil water content from 30% to 4%) in consecutive leaf segments comprising the leaf base (meristem region), elongation zone, the enclosed and exposed lamina, as well as basal sheath segments from the two next oldest leaves. In fully hydrated leaf tissues polymers of fructose (fructans) were the main WSC present and were mainly low molecular weight fructans of the inulin and neokestose series with the average degree of polymerization (DP) of fructan pools from 6 to 9. The highest fructan concentrations were present towards the leaf base. Fructan concentrations decreased over the course of the dry-down, although remained significantly higher in the meristem region of the tiller base with respect to any other tissue, until tissue water content fell below 45%. By day 49 of the dry-down period, the average DP of the fructan pool in tissues was from 3 to 5. Sucrose content increased in each tissue during the course of the dry-down, and was highest at the leaf base, where a concentration of 200 µmol g-1 dry weight was measured after 49 days of dry-down. Th

This study was designed to compare the effects of dietary supplementation with nondigestible carbohydrates, differing in fermentability by colonic bacteria, on hepatic steatosis in growing obese Zucker rats. Male Zucker fa/fa rats were divided into three groups: a control group that received the basal diet, a fructan group that received 10 g highly fermented Synergy 1/100 g diet and a cellulose group that received 10 g poorly fermented Vivapur Microcrystalline cellulose/100 g diet. Rats consuming fructan had a lower energy intake, a lower body weight and less triacylglycerol accumulation in the liver as assessed in vivo by nuclear magnetic resonance (NMR) spectroscopy, and ex vivo by biochemical and histochemical analysis compared with the control and/or cellulose groups. The high fermentation of fructans compared with cellulose was reflected by greater cecal contents and by a twofold greater propionate concentration in the portal vein of rats fed fructan compared with those fed cellulose. By measuring the capacity of hepatocytes isolated from liver of Zucker rats to synthesize triglycerides or total lipids from different precursors, we showed that propionate, at the concentrations measured in the portal vein of rats treated with fructan, selectively decreased the incorporation of acetate into total lipids, a phenomenon that could contribute, along with the lower energy intake, to less triglyceride accumulation in the liver of obese Zucker rats fed dietary fructans.

Prebiotics are defined as nondigestible food ingredients that beneficially affect the host by selectively stimulating the growth or the activity of one or a limited number of bacteria (bifidobacteria, lactobacilli) in the colon. Dietary fructans are nutritionally interesting oligosaccharides that strictly conform to the definition of prebiotics and (in view of experimental studies in animals and of less numerous studies in humans) exhibit interesting serum or hepatic lipid lowering properties. Other nondigestible/fermentable nutrients, which also modulate intestinal flora activity, exhibit cholesterol or triglyceride lowering effects. Are changes in intestinal bacterial flora composition or fermentation activity responsible for those effects? What is the future of prebiotics in the nutritional control of lipidaemia and cardiovascular disease risk in humans? Those questions only receive partial response in the present review because studies of the systemic effects of prebiotics are still in their infancy, and require fundamental research devoted to elucidating the biochemical and physiological events that allow prebiotics to exert systemic effects on lipid metabolism.

Inulin is extracted from the chicory root. It is a set of fructans with its monomers linked by means of beta(2-1) bonds. This linkage cannot be hydrolysed by either pancreatic or by brush border digestive enzymes in the upper intestinal tract of humans. As such the carbohydrates arrive in the colon, where they are fermented by bifidobacteria and other lactic acid producing bacteria, thus enhancing their relative populations in the gut. Recent research in experimental animal models revealed that inulin has significant anticarcinogenic properties. It acts chemopreventively by reducing the incidence of azoxymethane (AOM) - induced aberrant crypt foci and tumours in the colon. These effects may be due to the stimulation of bifidobacteria, which themselves have been shown to act as antigenotoxic in the colon and to reduce AOM-induced tumours. Also fermentation products, including the short-chain fatty acid butyrate, could contribute to the protective effects. In this case a mechanism may be the induction of apoptosis of already transformed cells. The experimental evidence from animal studies and from studies elucidating potential mechanisms strongly supports the possibility that inulin will contribute to reducing risks for colon cancer in humans. In order to obtain more insight into this possibility, human dietary intervention studies relating biomarkers of reduced risk to inulin consumption are needed.

Inulin and oligofructose, besides their effect on the gastro-intestinal tract, are also able to exert 'systemic' effect, namely by modifying the hepatic metabolism of lipids in several animal models. Feeding male Wistar rats on a carbohydrate-rich diet containing 10 % inulin or oligofructose significantly lowers serum triacylglycerol (TAG) and phospholipid concentrations. A lower hepatic lipogenesis, through a coordinate reduction of the activity and mRNA of lipogenic enzymes is a key event in the reduction of very low-density lipoprotein-TAG secretion by oligofructose. Oligofructose is also able to counteract triglyceride metabolism disorder occurring through dietary manipulation in animals, and sometimes independently on lipogenesis modulation: oligofructose reduces post-prandial triglyceridemia by 50 % and avoids the increase in serum free cholesterol level occurring in rats fed a Western-type high fat diet. Oligofructose protects rats against liver TAG accumulation (steatosis) induced by fructose, or occurring in obese Zucker fa/fa rats. The protective effect of dietary inulin and oligofructose on steatosis in animals, would be interesting, if confirmed in humans, since steatosis is one of the most frequent liver disorders, occurring together with the plurimetabolic syndrome, in overweight people. The panel of putative mediators of the systemic effects of inulin and oligofructose consists in either modifications in glucose/insulin homeostasis, the end-products of their colonic fermentation (i.e. propionate) reaching the liver by the portal vein, incretins and/or the availability of other nutrients. The identification of the key mediators of the systemic effects of inulin and oligofructose is the key to identify target function(s) (or dysfunction(s)), and finally individuals who would take an advantage of increasing their dietary intake.

Het gebruik van antimicrobiële groeibevorderaars (AMGB's) staat ter discussie en wordt in de toekomst mogelijk verboden. Met het vooruitzicht hierop is de mengvoersector bezig met het ontwikkelen van voerconcepten die een alternatief moeten zijn voor AMGB's. :Op verzoek van Speerstra Feed Ingredients BV te Lemmer heeft het Praktijkonderzoek Veehouderij een onderzoek uitgevoerd naar de effectiviteit van Intiboe, een fructooligosaccharide, als alternatief voor AMGB. :In het onderzoek zijn twee experimenten uitgevoerd, met elk drie proefbehandelingen (een positieve en negatieve controle en de behandeling met Intiboe). In beide experimenten werd een dosering van 300 gram/ton werkzame stof Intiboe toegepast. In experiment I werd een verdund (10 %-tig) mengsel (Intiboe 9-10) verwerkt en in experiment II een onverdund product (Intiboe9). Op een leeftijd van gemiddeld 4 weken zijn de biggen gespeend en ingedeeld voor de proef. Zij zijn vanaf spenen 34 dagen gevolgd. In beide experimenten zijn circa 540 biggen gevolgd. Per behandeling zijn 18 herhalingen uitgevoerd.

Several nondigestible but fermentable dietary carbohydrates are able to regulate lipemia and triglyceridemia in both humans and animals. The mechanism of their serum lipid-lowering effect remains to be elucidated. Oligofructose, which is a mixture of nondigestible and fermentable fructans, can decrease triacylglycerol in VLDL when given to rats. The triacylglycerol-lowering action of oligofructose is due to a reduction of de novo fatty acid synthesis in the liver through inhibition of all lipogenic enzymes, namely acetyl-CoA carboxylase (EC 6.4.1.2), fatty acid synthase, malic enzyme (EC 1.1.1.40), ATP citrate lyase (EC 4.1.3.8), and glucose-6-phosphate dehydrogenase (EC 1.1.1.49). Our results suggest that oligofructose decreases lipogenic enzyme gene expression. Postprandial insulin and glucose concentrations are low in the serum of oligofructose-fed animals and this could explain, at least partially, the metabolic effect of oligofructose. Moreover, some events occurring in the gastrointestinal tract after oligofructose feeding could be involved in the antilipogenic effect of this fructan: the production of propionate through fermentation, a modulation of the intestinal production of incretins (namely glucose-dependent insulinotropic peptide and glucagon-like peptide-1), or the modification of the availability of digestible carbohydrates. Recent studies showed that the hypotriglyceridemic effect of fructans also occurs in humans.

We studied the influence of oligofructose (OFS), a nondigestible fructan, on lipid metabolism in obese fa/fa Zucker rats. The addition of 10 g/100 g OFS to the diet slowed the increase in body weight without modifying serum triglycerides or glucose concentrations after 7 wk of treatment. However, an oral load of 2 g glucose and 5 g corn oil/kg body weight increased triglyceridemia more in OFS-fed rats than in control rats. After 10 wk, OFS decreased the hepatic concentration of triglycerides 57% relative to controls. The less severe steatosis was confirmed by histologic analysis. Among the key enzymes involved in fatty acid synthesis and esterification, only malic enzyme activity was significantly lower in OFS-fed rats than in controls. The epididymal fat mass was significantly lower in OFS-fed rats. In conclusion, dietary enrichment with OFS can counteract both the fat mass development and the hepatic steatosis that occur in obese Zucker rats. Future studies will be designed to clarify in obese animals the influence of dietary OFS on postprandial triglyceridemia, which is an important variable associated with the development of atherosclerosis in humans, and to analyze the biochemical mechanism underlying the "hepatoprotective" effect of OFS.

Fructan is a general term used for any carbohydrate in which one or more fructosyl-fructose link constitutes the majority of osidic bonds. This review focuses on the fate of inulin-type fructans (namely native chicory inulin, oligofructose produced by the partial enzymatic hydrolysis of chicory inulin, and synthetic fructans produced by enzymatic synthesis from sucrose) in the gastrointestinal tract, as well as on their systemic physiological effects on mineral absorption, carbohydrate and lipid metabolism, hormone balance, and nitrogen homeostasis. The scientific evidence for the functional claims of inulin-type fructans is discussed, as well as their potential application in risk reduction of disease, namely constipation, infectious diarrhea, cancer, osteoporosis, atherosclerotic cardiovascular disease, obesity, and non-insulin dependent diabetes.

BACKGROUND: The influence of 15% inulin or oligofructose incorporated in to the basal diet on the growth of transplantable mouse tumor (TLT) was investigated. MATERIAL AND METHODS: This dietary treatment was performed starting at day 7 before tumor transplantation and continued until the end of observation. The results were evaluated by the mortality rates in the ascitic form of tumor, or by twice weekly solid tumor measurements, with vernier caliper. Mortality rates in ascitic tumors and mean solid tumor surface in these experimental groups was compared with those of animals from control groups fed basal diet without supplementary beta (2-1) fructans. RESULTS: The growth of both forms of transplantable mouse tumors was significantly inhibited by the supplementation of the diet with inulin or oligofructose. CONCLUSION: Such a nontoxic dietary treatment appears to be easily used ad without any risk for patients, and is applicable as an adjuvant factor to classical protocols of human cancer therapy.

The aim of this study was to test the hypothesis that non-digestible fructans, namely oligofructose (OFS), are able to decrease post-prandial lipaemia in rats fed a high-fat diet composed of 10% lard, 4% corn oil and 0.15% cholesterol. Male Wistar rats were divided into three groups: group 1 was fed a standard low-fat diet (AO4), group 2 received the high-fat diet (HF) and group 3 received 10% (w/w) OFS in the HF diet (HF-OFS) for 3 weeks. The OFS supplementation reduced post-prandial triglyceridaemia by more than 50%, compared to both AO4 and HF groups. It also protected rats against the increase in free cholesterol serum level induced by the HF diet. The OFS did not prevent the HF-induced hepatic accumulation of triglycerides, phospholipids and cholesterol; however, histochemical analysis showed smaller lipid droplets in the liver of HF-OFS rats as compared to HF rats. Our results suggest that, when given in HF diet, OFS decreases serum triglycerides through an extra-hepatic event, namely by enhancing triglyceride-rich lipoprotein catabolism.

The objective of this investigation was to protect rats against exocrine pancreatic atrophy by adding 22% fructo-oligosaccharide (FOS), a natural fructan obtained from inulin, to the 50% copper-deficient diets containing qualitatively and quantitatively different carbohydrates. Young male Wistar rats were maintained on these diets for 10 wk, being weighed weekly then killed and autopsied. Major organs were weighed and histologically examined. Copper content in the diets was measured by flame atomic absorption spectroscopy. Incomplete (50%) copper deficiency avoided precocious mortality due to cardiovascular lesions and enabled another pathological condition to develop, consisting of the induction of exocrine pancreas atrophy. Introduction of gradually increasing percentages of fructose in diets at the level of 22, 42 and 62% induced a gradual increase in the copper-deficiency-mediated pathology in rats, expressed by an increase in exocrine pancreatic atrophy. 22% FOS introduced to the diet prevented the pathology induced by both fructose and partial copper deficiency better than starch added to diet at the level of 20 or 40%.