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Thomas L. Housley - One of the best experts on this subject based on the ideXlab platform.
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Purification and Characterization of Wheat β(2→1) Fructan:Fructan Fructosyl Transferase Activity
Plant physiology, 1992Co-Authors: Byeong-ryong Jeong, Thomas L. HousleyAbstract:Fructans are the major storage carbohydrate in vegetative tissues of wheat (Triticum aestivum L.). Fructan:fructan fructosyl transferase (FFT) catalyzes fructosyl transfer between fructan molecules to elongate the fructan chain. The objective of this research was to isolate this activity in wheat. Wheat (cv Caldwell) plants grown at 25°C for 3 weeks were transferred to 10°C to induce fructan synthesis. From the leaf blades kept at 10°C for 4 days, fructosyl transferase activity was purified using salt precipitation and a series of chromatographic procedures including size exclusion, anion-exchange, and affinity chromatography. The transferase activity was free from invertase and other fructan-metabolizing activities. Fructosyl transferase had a broad pH spectrum with a peak activity at 6.5. The temperature optimum was 30°C. The activity was specific for fructosyl transfer from β(2→1)-linked 1-Kestose or fructan to sucrose and β(2→1) fructosyl transfer to other fructans (1-FFT). Fructosyl transfer from oligofructans to sucrose was most efficient when 1-Kestose was used as donor molecule and declined as the degree of polymerization of the donor increased from 3 to 5. 1-FFT catalyzed the in vitro synthesis of inulin tetra- and penta-saccharides from 1-Kestose; however, formation of the tetrasaccharide was greatly reduced at high sucrose concentration. 6-Kestose could not act as donor molecule, but could accept a fructosyl moiety from 1-Kestose to produce bifurcose and a tetrasaccharide having a β(2→1) fructose attached to the terminal fructose of 6-Kestose. The role of this FFT activity in the synthesis of fructan in wheat is discussed.
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Fructosyl Transfer between 1-Kestose and Sucrose in Wheat Leaves
Plant physiology, 1991Co-Authors: Jan Kanabus, Nicholas C. Carpita, David M. Gibeaut, Thomas L. HousleyAbstract:The labeling pattern of the sugar moieties of 1-Kestose after in vivo pulse labeling with 14CO2 was not the same as that after in vitro labeling with 14C-sucrose. The two fructosyl residues of 1-Kestose had similar specific radioactivities after in vitro synthesis, but after in vivo radiolabeling the specific radioactivity of the terminal fructosyl moiety was significantly less than the internal fructosyl moiety. Evidence is presented that the uneven specific radioactivity of in vivo radiolabeling results from enzymatic transfer of terminal fructosyl residue from 1-Kestose to sucrose.
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Synthesis of inulin oligomers in tissue slices, protoplasts and intact vacuoles of Jerusalem artichoke
Journal of Plant Physiology, 1991Co-Authors: Nicholas C. Carpita, Felix Keller, David M. Gibeaut, Thomas L. Housley, Philippe MatileAbstract:Summary Tissue slices and protoplasts of Jerusalem artichoke ( Helianthus tuberosus L. cv. Bianco) incorporate radioactivity from glucose into sucrose, 1-Kestose, nystose (inulin tetrasaccharide) and other fructan oligomers, and intact isolated vacuoles absorb sucrose and incorporate radioactivity from sucrose into 1-Kestose. Gas-liquid chromatography and radiogas proportional counting demonstrated that, in all cases, the glucosyl and internal fructosyl units of 1-Kestose contained substantial amounts of radioactivity whereas the terminal fructosyl unit was essentially devoid of label. We propose that incorporation of radioactivity into 1-Kestose is primarily from transfer of the unlabeled terminal fructosyl unit of nascent 1-Kestose to labeled sucrose by fructan: fructan fructosyl transferase and not by sucrose: sucrose fructosyl transferase. Such reactions do not result in a net gain in fructan, and hence, more definitive estimations of SST activity and the net synthesis of fructans in vivo are needed. Our success preserving fructan metabolism in isolated vacuoles, however, provides a system to examine more closely the role of the tonoplast in vectorial transport of sucrose into the vacuole, glucose and fructose out of the vacuole, and the association of these transport processes with net increases in synthesis of 1-Kestose and fructans.
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Fructosyl transfer from sucrose and oligosaccharides during fructan synthesis in excised leaves of Lolium temulentum L.
New Phytologist, 1991Co-Authors: Thomas L. Housley, Ian M. Sims, Nicholas C. Carpita, David M. Gibeaut, Christopher J. PollockAbstract:summary Fructan biosynthesis begins with the transfer of a fructosyl moiety from one sucrose molecule to another to yield a trisaccharide. Trisaccharides may also arise by the reversible transfer of a fructosyl moiety from higher oligomers to sucrose but in this case there is no net fructan synthesis. Short-term and long-term exposure of detached illuminated leaf blades of Lolium temulentum (L.I to 14CO2 was used to examine the mechanism of transfer of fructosyl residues to sucrose. Two trisaccharides, 1-Kestose and neoKestose, were found to be radioactive when leaves excised and illuminated for 15 h -were exposed to NCO2 for 30 min. The label increased in neoKestose during the chase period, while that in 1-Kestose increased for the first 2 h of the chase period then declined for the remaining 4h. With a longer exposure to 14CO2 during the first 6 h of the induction period, three trisaccharides, neoKestose, 1-Kestose and 6-Kestose were radiolabelled. The label turned over in neoKestose and 1-Kestose, but continued to accumulate in 6-Kestose during a subsequent 18 h chase period. The specific activities of glucose and fructose of the sucrosyl portion and the terminal fructosyl moiety of the various trisaccharides were compared. In the rapid pulse-chase experiment the specific activity of the1 terminal fructosyl moiety was consistently less than that of the sucrosyl moiety. During the chase period, the specific activity of the terminal and internal fructose moieties became similar. These results indicate that in addition to trisaccharide formed by transfer of fructosyl units from sucrose, substantial amounts of both neoKestose and 1-Kestose are made by transfer of fructosyl units from higher oligomers onto sucrose in reactions probably localized in the vacuole.
María Fernández-lobato - One of the best experts on this subject based on the ideXlab platform.
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Yeast cultures expressing the Ffase from Schwanniomyces occidentalis, a simple system to produce the potential prebiotic sugar 6-Kestose.
Applied microbiology and biotechnology, 2018Co-Authors: David Rodrigo-frutos, David Piedrabuena, Julia Sanz-aparicio, María Fernández-lobatoAbstract:The β-fructofuranosidase Ffase from the yeast Schwanniomyces occidentalis produces potential prebiotic fructooligosaccharides with health-promoting properties, making it of biotechnological interest. Ffase is one of the highest and more selective known producers of 6-Kestose by transfructosylation of sucrose. In this work, production of 6-Kestose was simplified by directly using cultures of S. occidentalis and Saccharomyces cerevisiae expressing both the wild-type enzyme and a mutated Ffase variant including the Ser196Leu substitution (Ffase-Leu196). Best results were obtained using yeast cultures supplemented with sucrose and expressing the Ffase-Leu196, which after only 4 h produced ~ 116 g/L of 6-Kestose, twice the amount obtained with the corresponding purified enzyme. 6-Kestose represented ~ 70% of the products synthesized. In addition, a small amount of 1-Kestose and the neofructoligosaccharides neoKestose and blastose were also produced. The Ser196Leu substitution skewed production of 6-Kestose and neofructooligosaccharides resulting in an increase of ~ 2.2- and 1.5-fold, respectively, without affecting production of 1-Kestose. Supplementing yeast cultures with glucose clearly showed that blastose originates from direct fructosylation of glucose, a property that has not been described for other similar proteins from yeasts. Modeling neoKestose and blastose into the Ffase-active site revealed the molecular basis explaining the peculiar specificity of this enzyme.
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New insights into the fructosyltransferase activity of Schwanniomyces occidentalis β-fructofuranosidase, emerging from nonconventional codon usage and directed mutation
Applied and environmental microbiology, 2010Co-Authors: Miguel Álvaro-benito, Julia Sanz-aparicio, Miguel De Abreu, Francisco García-del Portillo, María Fernández-lobatoAbstract:Schwanniomyces occidentalis β-fructofuranosidase (Ffase) releases β-fructose from the nonreducing ends of β-fructans and synthesizes 6-Kestose and 1-Kestose, both considered prebiotic fructooligosaccharides. Analyzing the amino acid sequence of this protein revealed that it includes a serine instead of a leucine at position 196, caused by a nonuniversal decoding of the unique mRNA leucine codon CUG. Substitution of leucine for Ser196 dramatically lowers the apparent catalytic efficiency (k(cat)/K(m)) of the enzyme (approximately 1,000-fold), but surprisingly, its transferase activity is enhanced by almost 3-fold, as is the enzymes' specificity for 6-Kestose synthesis. The influence of 6 Ffase residues on enzyme activity was analyzed on both the Leu196/Ser196 backgrounds (Trp47, Asn49, Asn52, Ser111, Lys181, and Pro232). Only N52S and P232V mutations improved the transferase activity of the wild-type enzyme (about 1.6-fold). Modeling the transfructosylation products into the active site, in combination with an analysis of the kinetics and transfructosylation reactions, defined a new region responsible for the transferase specificity of the enzyme.
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Biochemical characterization of a β‐fructofuranosidase from Rhodotorula dairenensis with transfructosylating activity
FEMS yeast research, 2009Co-Authors: Patricia Gutiérrez-alonso, Francisco J. Plou, Lucia Fernandez-arrojo, María Fernández-lobatoAbstract:An extracellular β-fructofuranosidase from the yeast Rhodotorula dairenensis was characterized biochemically. The enzyme molecular mass was estimated to be 680 kDa by analytical gel filtration and 172 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, of which the N -linked carbohydrate accounts for 16% of the total mass. It displays optimum activity at pH 5 and 55–60 °C. The enzyme shows broad substrate specificity, hydrolyzing sucrose, 1-Kestose, nystose, leucrose, raffinose and inulin. Although the main reaction catalyzed by this enzyme is sucrose hydrolysis, it also exhibits transfructosylating activity that, unlike other microbial β-fructofuranosidases, produces a varied type of prebiotic fructooligosaccharides containing β-(2→1)- and β-(2→6)-linked fructose oligomers. The maximum concentration of fructooligosaccharides was reached at 75% sucrose conversion and it was 87.9 g L−1. The 17.0% (w/w) referred to the total amount of sugars in the reaction mixture. At this point, the amounts of 6-Kestose, neoKestose, 1-Kestose and tetrasaccharides were 68.9, 10.6, 2.6 and 12.7 g L−1, respectively.
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Characterization of a β-fructofuranosidase from Schwanniomyces occidentalis with transfructosylating activity yielding the prebiotic 6-Kestose
Journal of biotechnology, 2007Co-Authors: Miguel Álvaro-benito, Julio Polaina, Miguel De Abreu, Lucia Fernandez-arrojo, Francisco J. Plou, Jesús Jiménez-barbero, Antonio Ballesteros, María Fernández-lobatoAbstract:Abstract β-Fructofuranosidases are powerful tools in industrial biotechnology. We have characterized an extracellular β-fructofuranosidase from the yeast Schwanniomyces occidentalis. The enzyme shows broad substrate specificity, hydrolyzing sucrose, 1-Kestose, nystose and raffinose, with different catalytic efficiencies (kcat/Km). Although the main reaction catalysed by this enzyme is sucrose hydrolysis, it also produces two fructooligosaccharides (FOS) by transfructosylation. A combination of 1H, 13C and 2D-NMR techniques shows that the major product is the prebiotic trisaccharide 6-Kestose. The 6-Kestose yield obtained with this β-fructofuranosidase is, to our concern, higher than those reported with other 6-Kestose-producing enzymes, both at the kinetic maximum (76 g l−1) and at reaction equilibrium (44 g l−1). The total FOS production in the kinetic maximum was 101 g l−1, which corresponded to 16.4% (w/w) referred to the total carbohydrates in the reaction mixture.
Andres Wiemken - One of the best experts on this subject based on the ideXlab platform.
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Cloning and Functional Analysis of Sucrose:Sucrose 1-Fructosyltransferase from Tall Fescue
Plant physiology, 2000Co-Authors: Marcel Lüscher, Urs Hochstrasser, Thomas Boller, Guido Vogel, Roger A. Aeschbacher, Virginie Galati, C. J. Nelson, Andres WiemkenAbstract:Enzymes of grasses involved in fructan synthesis are of interest since they play a major role in assimilate partitioning and allocation, for instance in the leaf growth zone. Several fructosyltransferases from tall fescue ( Festuca arundinacea ) have previously been purified (Luscher and Nelson, 1995). It is surprising that all of these enzyme preparations appeared to act both as sucrose (Suc):Suc 1-fructosyl transferases (1-SST) and as fructan:fructan 6 G -fructosyl transferases. Here we report the cloning of a cDNA corresponding to the predominant protein in one of the fructosyl transferase preparations, its transient expression in tobacco protoplasts, and its functional analysis in the methylotrophic yeast, Pichia pastoris . When the cDNA was transiently expressed in tobacco protoplasts, the corresponding enzyme preparations produced 1-Kestose from Suc, showing that the cDNA encodes a 1-SST. When the cDNA was expressed in P. pastoris , the recombinant protein had all the properties of known 1-SSTs, namely 1-Kestose production, moderate nystose production, lack of 6-Kestose production, and fructan exohydrolase activity with 1-Kestose as the substrate. The physical properties were similar to those of the previously purified enzyme, except for its apparent lack of fructan:fructan 6 G -fructosyl transferase activity. The expression pattern of the corresponding mRNA was studied in different zones of the growing leaves, and it was shown that transcript levels matched the 1-SST activity and fructan content.
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Isolation of sucrose: sucrose 1‐fructosyltransferase (1‐SST) from barley (Hordeum vulgare)
New Phytologist, 2000Co-Authors: Marcel Lüscher, Urs Hochstrasser, Thomas Boller, Andres WiemkenAbstract:The enzyme sucrose: sucrose 1-fructosyltransferase was partially purified from barley leaf growth zones. Four steps (ammonium sulphate precipitation and polyethylene glycol precipitation, followed by chromatography on Concanavalin A-sepharose and hydroxylapatite) yielded a 35-fold purification. The resulting preparation of 1-SST which still contained a number of different activities related to fructan metabolism, was subjected to preparative isoelectric focusing, and sections of the gel were analysed individually for 1-SST and related activities, using sucrose and 1-Kestose as substrates. This procedure yielded a 196-fold purification and revealed the presence of two isozymes of 1-SST with pI values of 4.93 and 4.99, as determined by analytical isoelectric focusing of the corresponding fractions. Both isozymes produced glucose and 1-Kestose when incubated with sucrose. In addition, small amounts of 6-Kestose and tetrasaccharides were formed. In particular, one of the two 1-SST isozymes yielded fructose when incubated with 1-Kestose, indicating that it also acts as a fructan exohydrolase. The other isozyme exhibited less fructan exohydrolase activity. Nystose was also degraded by the fructan exohydrolase activity but less than 1-Kestose, whereas 6-Kestose was not a substrate for the enzyme. Incubation of both 1-SSTs with different concentrations of sucrose showed that the enzyme was not saturated even at 500 mM. As for the barley sucrose: fructan 6-fructosyltransferase, both isozymes of 1-SST yielded two polypeptide bands of molecular weight 50 and 22 kDa upon sodium dodecylsulphate polyacrylamide gel electrophoresis, suggesting their close relationship to invertase (composed of two subunits of similar size), as previously reported for other plants.
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Fructan Synthesis in Excised Barley Leaves (Identification of Two Sucrose-Sucrose Fructosyltransferases Induced by Light and Their Separation from Constitutive Invertases).
Plant physiology, 1993Co-Authors: Urs Simmen, Thomas Boller, David M. Obenland, Andres WiemkenAbstract:Excised leaves of barley (Hordeum vulgare L.) exposed to continuous light accumulate large amounts of soluble carbohydrates. Carbohydrates were analyzed in deionized extracts by high-pressure liquid chromatography on an anion exchange column coupled with pulsed amperometric detection. During the first few hours of illumination, the main sugar to accumulate was sucrose. The levels of glucose and fructans (oligofructosylsucroses) increased later. The trisaccharide 1-Kestose (1-kestotriose) predominated initially among the fructans. Later, 6-Kestose (6-kestotriose) and tetra- and pentasaccharides accumulated also. Total extracts from barley leaves were chromatographed on a MonoQ column, and each fraction was assayed for enzymes of interest by incubation with 200 mM sucrose for 3 h, followed by carbohydrate analysis. Freshly excised leaves yielded two peaks of invertase, characterized by formation of fructose and glucose, but had almost no trisaccharide-forming activities. In leaves exposed to continuous light, two new enzyme activities appeared that generated fructan-related trisaccharides and glucose from sucrose. One of them was a sucrose-sucrose fructosyl-1-transferase (1-SST), producing 1-Kestose exclusively: the peak fractions of this activity contained almost no invertase. The other was a sucrose-sucrose fructosyl-6-transferase (6-SST), producing 6-Kestose. It comigrated with one of the constitutive invertases on MonoQ but was separated from it by subsequent chromatography on alkyl Superose. Nevertheless, the preparation retained invertase activity, suggesting that this enzyme may act both as fructosidase and fructosyltransferase. When incubated with 1-Kestose in addition to sucrose, this enzyme formed less 6-Kestose but instead produced large amounts of the tetrasaccharide bifurcose (1&6-kestotetraose), the main fructan tetrasaccharide accumulating in vivo. These results suggest that two inducible enzymes, 1-SST and 6-SST, act in concert to initiate fructan accumulation in barley leaves.
Takumi Tochio - One of the best experts on this subject based on the ideXlab platform.
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1-Kestose supplementation mitigates the progressive deterioration of glucose metabolism in type 2 diabetes OLETF rats
Scientific reports, 2020Co-Authors: Ayako Watanabe, Akihito Endo, Takumi Tochio, Yoshihiro Kadota, Rina Kamio, Yoshiharu Shimomura, Yasuyuki KitauraAbstract:The fructooligosaccharide 1-Kestose cannot be hydrolyzed by gastrointestinal enzymes, and is instead fermented by the gut microbiota. Previous studies suggest that 1-Kestose promotes increases in butyrate concentrations in vitro and in the ceca of rats. Low levels of butyrate-producing microbiota are frequently observed in the gut of patients and experimental animals with type 2 diabetes (T2D). However, little is known about the role of 1-Kestose in increasing the butyrate-producing microbiota and improving the metabolic conditions in type 2 diabetic animals. Here, we demonstrate that supplementation with 1-Kestose suppressed the development of diabetes in Otsuka Long-Evans Tokushima Fatty (OLETF) rats, possibly through improved glucose tolerance. We showed that the cecal contents of rats fed 1-Kestose were high in butyrate and harbored a higher proportion of the butyrate-producing genus Anaerostipes compared to rats fed a control diet. These findings illustrate how 1-Kestose modifications to the gut microbiota impact glucose metabolism of T2D, and provide a potential preventative strategy to control glucose metabolism associated with dysregulated insulin secretion.
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activation of butyrate producing bacteria as well as bifidobacteria in the cat intestinal microbiota by the administration of 1 Kestose the smallest component of fructo oligosaccharide
Journal of Veterinary Medical Science, 2020Co-Authors: Mikako Shinohara, Takumi Tochio, Masaharu Kiyosue, Seiji Kimura, Yasuhiro KogaAbstract:1-Kestose is a structural component of fructo-oligosaccharides and is composed of 2 fructose residues bound to sucrose through β2-1 bonds. In the present study, the influence of the ingestion of 1-Kestose on the intestinal microbiota was investigated in cats. Six healthy cats were administered 1 g/day of 1-Kestose for 8 weeks followed by a 2-week wash-out period. Fecal samples were collected from cats after 0, 4, 8, and 10 weeks. The intestinal microbiota was examined by a 16S rRNA gene metagenomic analysis and real-time PCR. Short-chain fatty acids were measured by GC/MS. The results suggested that the intestinal bacterial community structure in feline assigned to this study was divided into 2 types: one group mainly composed of the genus Lactobacillus (GA) and the other mainly composed of the genus Blautia with very few bacteria of Lactobacillus (GB). Furthermore, the number of Bifidobacterium slightly increased after the administration of 1-Kestose (at 4 and 8 weeks) (P<0.1). The administration of 1-Kestose also increased the abundance of Megasphaera, the butyric acid-producing bacteria, at 4 and 8 weeks (P<0.1). Furthermore, an increase in butyric acid levels was observed after the administration of 1-Kestose for 4 weeks (P<0.1). These results suggest that 1-Kestose activated butyrate-producing bacteria as well as bifidobacteria and propose its potential as a new generation prebiotic.
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Activation of butyrate-producing bacteria as well as bifidobacteria in the cat intestinal microbiota by the administration of 1-Kestose, the smallest component of fructo-oligosaccharide.
The Journal of veterinary medical science, 2020Co-Authors: Mikako Shinohara, Takumi Tochio, Masaharu Kiyosue, Seiji Kimura, Yasuhiro KogaAbstract:1-Kestose is a structural component of fructo-oligosaccharides and is composed of 2 fructose residues bound to sucrose through β2-1 bonds. In the present study, the influence of the ingestion of 1-Kestose on the intestinal microbiota was investigated in cats. Six healthy cats were administered 1 g/day of 1-Kestose for 8 weeks followed by a 2-week wash-out period. Fecal samples were collected from cats after 0, 4, 8, and 10 weeks. The intestinal microbiota was examined by a 16S rRNA gene metagenomic analysis and real-time PCR. Short-chain fatty acids were measured by GC/MS. The results suggested that the intestinal bacterial community structure in feline assigned to this study was divided into 2 types: one group mainly composed of the genus Lactobacillus (GA) and the other mainly composed of the genus Blautia with very few bacteria of Lactobacillus (GB). Furthermore, the number of Bifidobacterium slightly increased after the administration of 1-Kestose (at 4 and 8 weeks) (P
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Reply to Comment on Watanabe, A.; Kadota, Y.; Yokoyama, H.; Tsuruda, S.; Kamio, R.; Tochio, T.; Shimomura, Y.; Kitaura, Y. Experimental Determination of the Threshold Dose for Bifidogenic Activity of Dietary 1-Kestose in Rats. Foods 2020, 9, 4
Foods (Basel Switzerland), 2020Co-Authors: Ayako Watanabe, Takumi Tochio, Yoshihiro Kadota, Yoshiharu Shimomura, Yasuyuki KitauraAbstract:The manuscript entitled "Comment on Experimental Determination of the Threshold Dose for Bifidogenic Activity of Dietary 1-Kestose in Rats" by Shen et al [...].
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Experimental Determination of the Threshold Dose for Bifidogenic Activity of Dietary 1-Kestose in Rats.
Foods (Basel Switzerland), 2019Co-Authors: Ayako Watanabe, Takumi Tochio, Yoshihiro Kadota, Hijiri Yokoyama, Shunya Tsuruda, Rina Kamio, Yoshiharu Shimomura, Yasuyuki KitauraAbstract:1-Kestose is a non-digestible oligosaccharide consisting of glucose linked to two fructose units. While 1-Kestose is not digested in the small intestine of mammals, it is fermented in the ceca and colon, where the growth of bifidobacteria is promoted. In the present study, we assessed the threshold dose of dietary 1-Kestose that increased cecal bifidobacterial levels in rats. Rats were fed experimental diets containing 0% to 0.3% 1-Kestose for four weeks. The levels of the genus Bifidobacterium and total gut bacteria were significantly increased in cecal samples of rats fed the 0.3% 1-Kestose diet. Further, a significant correlation between the dose of 1-Kestose and the levels of cecal Bifidobacterium and total gut bacteria was observed. The minimum dose of dietary 1-Kestose to induce significant bifidogenic activity in rats was 0.3% by weight in the diet.
Yasuyuki Kitaura - One of the best experts on this subject based on the ideXlab platform.
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1-Kestose supplementation mitigates the progressive deterioration of glucose metabolism in type 2 diabetes OLETF rats
Scientific reports, 2020Co-Authors: Ayako Watanabe, Akihito Endo, Takumi Tochio, Yoshihiro Kadota, Rina Kamio, Yoshiharu Shimomura, Yasuyuki KitauraAbstract:The fructooligosaccharide 1-Kestose cannot be hydrolyzed by gastrointestinal enzymes, and is instead fermented by the gut microbiota. Previous studies suggest that 1-Kestose promotes increases in butyrate concentrations in vitro and in the ceca of rats. Low levels of butyrate-producing microbiota are frequently observed in the gut of patients and experimental animals with type 2 diabetes (T2D). However, little is known about the role of 1-Kestose in increasing the butyrate-producing microbiota and improving the metabolic conditions in type 2 diabetic animals. Here, we demonstrate that supplementation with 1-Kestose suppressed the development of diabetes in Otsuka Long-Evans Tokushima Fatty (OLETF) rats, possibly through improved glucose tolerance. We showed that the cecal contents of rats fed 1-Kestose were high in butyrate and harbored a higher proportion of the butyrate-producing genus Anaerostipes compared to rats fed a control diet. These findings illustrate how 1-Kestose modifications to the gut microbiota impact glucose metabolism of T2D, and provide a potential preventative strategy to control glucose metabolism associated with dysregulated insulin secretion.
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Reply to Comment on Watanabe, A.; Kadota, Y.; Yokoyama, H.; Tsuruda, S.; Kamio, R.; Tochio, T.; Shimomura, Y.; Kitaura, Y. Experimental Determination of the Threshold Dose for Bifidogenic Activity of Dietary 1-Kestose in Rats. Foods 2020, 9, 4
Foods (Basel Switzerland), 2020Co-Authors: Ayako Watanabe, Takumi Tochio, Yoshihiro Kadota, Yoshiharu Shimomura, Yasuyuki KitauraAbstract:The manuscript entitled "Comment on Experimental Determination of the Threshold Dose for Bifidogenic Activity of Dietary 1-Kestose in Rats" by Shen et al [...].
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Experimental Determination of the Threshold Dose for Bifidogenic Activity of Dietary 1-Kestose in Rats.
Foods (Basel Switzerland), 2019Co-Authors: Ayako Watanabe, Takumi Tochio, Yoshihiro Kadota, Hijiri Yokoyama, Shunya Tsuruda, Rina Kamio, Yoshiharu Shimomura, Yasuyuki KitauraAbstract:1-Kestose is a non-digestible oligosaccharide consisting of glucose linked to two fructose units. While 1-Kestose is not digested in the small intestine of mammals, it is fermented in the ceca and colon, where the growth of bifidobacteria is promoted. In the present study, we assessed the threshold dose of dietary 1-Kestose that increased cecal bifidobacterial levels in rats. Rats were fed experimental diets containing 0% to 0.3% 1-Kestose for four weeks. The levels of the genus Bifidobacterium and total gut bacteria were significantly increased in cecal samples of rats fed the 0.3% 1-Kestose diet. Further, a significant correlation between the dose of 1-Kestose and the levels of cecal Bifidobacterium and total gut bacteria was observed. The minimum dose of dietary 1-Kestose to induce significant bifidogenic activity in rats was 0.3% by weight in the diet.
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Feeding of 1-Kestose Induces Glutathione-S-Transferase Expression in Mouse Liver
MDPI AG, 2019Co-Authors: Takumi Tochio, Yoshihiro Kadota, Yoshiharu Shimomura, Yasuyuki Kitaura, Mikako Shinohara, Yuki Ueno, Kanako Minoda, Toshihiko OsawaAbstract:Functional food ingredients, including prebiotics, have been increasingly developed for human health. The improvement of the human intestinal environment is one of their main targets. Fructooligosaccarides (FOS) are oligosaccharide fructans that are well studied and commercialized prebiotics. 1-Kestose, one of the components of FOS, is considered to be a key prebiotic component in FOS. However, to our knowledge, no studies have been reported on the physiological efficacy of 1-Kestose regarding its anti-oxidative activity. In the present study, we examined the effects of dietary 1-Kestose on gene expression of antioxidative enzymes in the liver, kidney and epididymal adipose tissue of mice by quantitative RT-PCR (qRT-PCR). We demonstrated that a 1-Kestose-rich diet increased mRNA and enzymatic activity levels of glutathione-S-transferase (GST) in mouse liver. These results suggest the possibility that dietary 1-Kestose as a prebiotic may enhance antioxidative activity in mice
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An Alteration in the Cecal Microbiota Composition by Feeding of 1-Kestose Results in a Marked Increase in the Cecal Butyrate Content in Rats.
PloS one, 2016Co-Authors: Takumi Tochio, Akihito Endo, Yasuyuki Kitaura, Saki Nakamura, Chie Sugawa, Motoki Takahashi, Yoshiharu ShimomuraAbstract:Functional food ingredients, including prebiotics, have been ardently developed for improving the intestinal environment. Fructooligosaccarides (FOS), including fructans, are the well researched and commercialized prebiotics. However, to our knowledge, few studies have been conducted on the physiological effects of each component of FOS as prebiotics. 1-Kestose, a component of FOS, is composed of one glucose and two fructose molecules, and is considered as a key prebiotic component in short-chain FOS. In the present study, we examined the effects of dietary 1-Kestose using 0.5–5% 1-Kestose diets on cecal microbiota composition and cecal contents of short-chain fatty acids and lactate in rats. The findings indicate that dietary 1-Kestose induced cecal hypertrophy and alterations in the cecal microbiota composition, including a marked increase in the cell number of Bifidobacterium spp. These alterations were associated with significant increases in acetate and lactate, and a marked increase in butyrate in cecal contents. Furthermore, dietary 1-Kestose induced a significant decrease in serum insulin concentration in rats fed 2.5–5% 1-Kestose diet. These findings suggest a potential of 1-Kestose to be a prebiotic for improving the metabolism of the host.
