SEARCH · PubMed Health

Results for “isomaltulose”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

PubMed1996

The effects of isomaltulose, isomalt, and isomaltulose-based oligomers on mineral absorption and retention.

We carried out a balance study to examine the effects of isomaltulose, lactose, isomalt, and isomaltulose-based oligomers (IBOs) on mineral (calcium, magnesium, phosphorus, and iron) absorption and retention. Four-week-old male Wistar rats were divided into five groups of six rats each and fed a basal diet or diet the containing either 5% isomaltulose, 5% lactose, 5% isomalts or isomaltulose-based oligomers (IBOs) ad libitum for 16 d. After 1 wk, the animals were subjected to a 5-d mineral (calcium, magnesium, phosphorus, and iron) balance study. The isomalt feeding, as well as the IBOs feeding, led to significantly elevated mineral absorption and retention. On the other hand, lactose feeding, widely known to enhance calcium absorption, increased only calcium absorption and isomaltulose feeding did not affect mineral absorption or retention. The organic acids in cecum contents were increased by IBOs or isomalt feeding. Succinic and acetic acids in cecum contents were significantly increased by IBOs feeding. Similarly, succinic, acetic, and i-valeric acids and total amount of organic acid in cecum content were significantly increased by isomalt feeding. Although the organic acids in cecum contents were increased by IBOs or isomalt feeding, the pH values and acidity in cecum contents were not changed by IBOs or isomalt feeding. The effect of addition of various organic acids to the mucosal fluid was examined with in vitro study using a hindgut segment. By the addition of acetic acid, and butyric acid, the mineral (calcium, magnesium, and phosphorus) uptake was increased.

Animals↗

PubMed2006

Conversion of sucrose into isomaltulose by Enterobacter sp. FMB1, an isomaltulose-producing microorganism isolated from traditional Korean food.

Over 500 microorganisms isolated from Korean traditional foods, Maeju (source of soybean paste) and Nuruk (Korean koji), were screened to obtain an isomaltulose-producing microorganism. It was identified as Enterobacter sp. FMB-1 by 16S rRNA sequencing and the API 20E system. It had a greater than 90% conversion of sucrose (as 4 g/l) to isomaltulose in 2 days. Small amounts of trehalulose, glucose, and fructose were produced as byproducts, implying that this strain could be possibly employed in the production of isomaltulose in industry.

Enterobacter↗

PubMed2002

Isomaltulose (Palatinose): a review of biological and toxicological studies.

Isomaltulose is a natural occurring disaccharide composed of alpha-1,6-linked glucose and fructose. Commercial isomaltulose is produced from sucrose by enzymatic rearrangement and has been used as a sugar in Japan since 1985. It is particularly suitable as a non-cariogenic sucrose replacement and is favorable in products for diabetics and prediabetic dispositions. In vivo studies with rats and pigs indicate that isomaltulose is completely hydrolyzed and absorbed in the small intestine. This is supported by in vitro studies showing that intestinal disaccharidases from various species (including man) can hydrolyze isomaltulose. The rate of hydrolysis, however, is very slow compared with sucrose and maltose. Thus, blood glucose and insulin levels in humans after oral administration rise slower and reach lower maxima than after sucrose administration. After absorption, fructose and glucose are metabolized as typical for these monosaccharides. From intravenous studies it can be assumed that any systemic isomaltulose would be hydrolyzed as well, or excreted in urine. In several subchronic toxicity studies, the administration of large doses (up to 7.0 and 8.1 g/kg body weight/day in male and female rats, respectively) of isomaltulose, did not result in adverse effects. Isomaltulose induced neither embryotoxic or teratogenic effects in rat foetuses, nor maternal toxicity at levels up to 7 g/kg body weight/day. Isomaltulose was non-mutagenic in the Ames test. As hydrolysis in the small intestine is complete, even high levels of isomaltulose are well tolerated in animals and humans. In studies with healthy as well as diabetic subjects high doses up to 50 g were tolerated without signs of intestinal discomfort. On the basis of the data reviewed it is concluded that the use of isomaltulose as an alternative sugar is as safe as the use of other digestible sugars consisting of glucose and fructose.

Animals↗

PubMed2004

Characterization of Pantoea dispersa UQ68J: producer of a highly efficient sucrose isomerase for isomaltulose biosynthesis.

AIMS: Isolation, identification and characterization of a highly efficient isomaltulose producer. METHODS AND RESULTS: After an enrichment procedure for bacteria likely to metabolize isomaltulose in sucrose-rich environments, 578 isolates were screened for efficient isomaltulose biosynthesis using an aniline/diphenylamine assay and capillary electrophoresis. An isolate designated UQ68J was exceptionally efficient in sucrose isomerase activity. Conversion of sucrose into isomaltulose by UQ68J (enzyme activity of 90-100 U mg(-1) DW) was much faster than the current industrial strain Protaminobacter rubrum CBS574.77 (41-66 U mg(-1) DW) or a reference strain of Erwinia rhapontici (0.3-0.9 U mg(-1) DW). Maximum yield of isomaltulose at 78-80% of supplied sucrose was achieved in less than half the reaction time needed by CBS574.77, and the amount of contaminating trehalulose (4%) was the lowest recorded from an isomaltulose-producing microbe. UQ68J is a Gram negative, facultatively anaerobic, motile, noncapsulate, straight rod-shaped bacterium producing acid but no gas from glucose. Based on 16S rDNA analysis UQ68J is closest to Klebsiella oxytoca, but it differs from Klebsiella in defining characteristics and most closely resembles Pantoea dispersa in phenotype. SIGNIFICANCE AND IMPACT OF STUDY: This organism is likely to have substantial advantage over previously characterized sucrose isomerase producers for the industrial production of isomaltulose.

Bioreactors↗

PubMed2026

Effects of continuous isomaltulose-containing gummy intake on interstitial glucose and salivary hormones during an 18-hole golf round: a randomized, double-blind controlled pilot study.

BACKGROUND: Golf is a prolonged, moderate-intensity sport requiring sustained physiological stability to manage cumulative stress and maintain performance. Although carbohydrate intake is commonly used to reduce fatigue, rapidly absorbed sugar-induced rapid blood glucose fluctuations may induce volatile arousal and latent metabolic stress. Isomaltulose, a slow-digesting disaccharide, provides a steadier glucose supply compared with sucrose. This exploratory pilot study examined the effects of isomaltulose intake on physiological stress markers, glycemic dynamics, and subjective responses during a competitive 18-hole golf round. METHODS: Twenty-three male collegiate golfers were randomized to either the isomaltulose group (ISO; n = 12) or the sucrose group (CON; n = 11) in a double-blind controlled trial. Participants consumed gummies containing isomaltulose or sucrose immediately after each hole (12.1 g carbohydrate per hole; total carbohydrate intake: 217.5 g). Primary outcomes were salivary stress markers [cortisol, testosterone, and dehydroepiandrosterone sulfate (DHEAS)] levels. Secondary outcomes included interstitial glucose concentration measured via continuous glucose monitoring, subjective assessments (i.e. sleepiness, relaxation, and concentration), and golf performance (18-hole score). Between-group comparisons at each time point were conducted using planned Welch's t-tests. RESULTS: No significant between-group differences were observed for 18-hole score (p = 0.38) or mean interstitial glucose concentration (p = 0.20). However, exploratory analyses revealed distinct hormonal variations; salivary DHEAS and testosterone levels were higher in the ISO group during the latter half of the round (p < 0.05), whereas both declined in the CON group. Regarding glycemic variability, the ISO group demonstrated a more stable glucose profile with a medium effect size for lower standard deviation (ISO: 14.7 ± 1.9 vs. CON: 16.7 ± 4.6 mg/dL; d = 0.58), although this difference was not significant. Conversely, subjective outcomes diverged; the CON group reported significantly greater subjective arousal (wakefulness and relaxation) (p < 0.01) relative to the ISO group. CONCLUSIONS: In conclusion, continuous intake of isomaltulose-containing gummies during an 18-hole golf round was associated with differences in selected physiological markers, including DHEAS and testosterone concentrations. However, these findings were not accompanied by improvements in objective golf performance outcomes compared with sucrose-containing gummies. Isomaltulose may influence glycemic dynamics and hormonal responses during prolonged golf play; however, the practical significance of these effects remains exploratory. Further studies with larger sample sizes and appropriate repeated-measures frameworks are needed to determine whether such physiological changes translate into meaningful performance or recovery benefits.

Humans↗

PubMed1990

Plaque formation of dietary isomaltulose in humans.

The plaque formation of isomaltulose, a sucrose isomer, was examined in 15 human volunteers with both diet and oral hygiene under supervision. The subjects were requested to refrain from all oral hygiene procedures for 3 days and were provided between-meal snacks containing 157 g of 4 test sugars (100% isomaltulose, 70% isomaltulose + 30% sucrose, 50% isomaltulose + 50% sucrose, and 100% sucrose). The study was repeated 4 times over 4 weeks. The isomaltulose diet resulted in the lowest plaque index, while sucrose induced a significantly greater deposition. In the absence of sucrose-containing snacks, mutans streptococci in saliva decreased below the baseline level. These results suggest that isomaltulose may be a suitable substitute for sucrose in between meal snacks.

Adult↗

PubMed2006

Isomaltulose production using free cells: optimisation of a culture medium containing agricultural wastes and conversion in repeated-batch processes.

The enzyme glucosyltransferase is an industrially important enzyme since it produces non-cariogenic isomaltulose (6-O-alpha-D-glucopyronosyl-1-6-D-fructofuranose) from sucrose by intramolecular transglucosylation. The experimental designs and response surface methodology (RSM) were applied for the optimisation of the nutrient concentrations in the culture medium for the production of glucosyltransferase by Erwinia sp. D12 in shaken flasks at 200 rpm and 30 degrees C. A statistical analysis of the results showed that, in the range studied, the factors had a significant effect (P < 0.05) on glucosyltransferase production and the highest enzyme activity (10.84 U/ml) was observed in culture medium containing sugar cane molasses (150 g l(-1)), corn steep liquor (20 g l(-1)), yeast extract Prodex Lac SD (15 g l(-1)) and K2HPO4 (0.5 g l(-1)) after 8 h at 30 degrees C. The production of cell biomass by the strain of Erwinia sp. D12 was carried out in a 6.6-l fermenter with a mixing rate of 200 rpm and an aeration rate of 1 vvm. Fermentation time, cellular growth, medium pH and glucosyltransferase production were observed. The greatest glucosyltransferase activity was 22.49 U/ml, obtained after 8 h of fermentation. The isomaltulose production from sucrose was performed using free Erwinia sp. D12 cells in a batch process using an orbital shaker. The influence of the parameters sucrose concentration, temperature, pH, and cell concentration on the conversion of sucrose into isomaltulose was studied. The free cells showed a high conversion rate of sucrose into isomaltulose using batch fermentation, obtaining an isomaltulose yield of 72.11% from sucrose solution 35% at 35 degrees C.

Biomass↗

PubMed2003

Substrate induction of isomaltulose synthase in a newly isolated Klebsiella sp. LX3.

AIMS: Production of isomaltulose by newly isolated Klebsiella sp. LX3. METHODS AND RESULTS: The bacterial isolate LX3, which transforms sucrose to isomaltulose and trehalulose, has been isolated from a soil sample in Singapore. Morphological and biochemical analysis, as well as 16s rRNA sequence demonstrated that the isolate could represent a new member of genus Klebsiella. The strain has several interesting features. The immobilized cells of Klebsiella sp. LX3 convert more than 99% of sucrose to products that consist of more than 87% of isomaltulose, 11.6% of trehalulose, and <1% of glucose. CONCLUSIONS: The production of isomaltulose synthase in isolate LX3 is inducible by its substrate sucrose and the sugars containing a fructofuranosyl group. SIGNIFICANCE AND IMPACT OF STUDY: It would be useful for future biotechnological applications to understand the structural features or motifs of the isomaltulose synthases that determine the sucrose conversion efficiency and the ratio of the conversion products.

Bacteriological Techniques↗

PubMed2003

A motif rich in charged residues determines product specificity in isomaltulose synthase.

Isomaltulose synthase (PalI) catalyzes hydrolysis of sucrose and formation of alpha-1,6 and alpha-1,1 bonds to produce isomaltulose (alpha-D-glucosylpyranosyl-1,6-D-fructofranose) and small amount of trehalulose (alpha-D-glucosylpyranosyl-1,1-D-fructofranose). A potential isomaltulose synthase-specific motif ((325)RLDRD(329)), that contains a 'DxD' motif conserved in many glycosyltransferases, was identified based on sequence comparison with reference to the secondary structural features of PalI and homologs. Site-directed mutagenesis analysis of the motif showed that the four charged amino acid residues (Arg(325), Arg(328), Asp(327) and Asp(329)) influence the enzyme kinetics and determine the product specificity. Mutation of these four residues increased trehalulose formation by 17-61% and decreased isomaltulose by 26-67%. We conclude that the 'RLDRD' motif controls the product specificity of PalI.

Amino Acid Motifs↗

PubMedDate not supplied

Embryotoxicity/teratogenicity study with isomaltulose (Palatinose) in rats.

The embryotoxicity/teratogenicity of the natural sweetener isomaltulose (Palatinose) was studied in Wistar rats. Groups of 24 mated females were fed diets containing isomaltulose at levels of 0, 2.5, 5 and 10% from day 0 to day 21 of pregnancy. The dams were killed on day 21 of pregnancy. No maternal toxicity occurred and no effects on reproductive performance, nor on embryonic or foetal development, including visceral and skeletal examination, were seen in any of the groups fed isomaltulose. The dietary level of 10% isomaltulose was equivalent to about 7 g/kg body weight/day.

Abnormalities, Drug-Induced↗

PubMed2024

Over expression of modified Isomaltulose Synthase Gene II (ImSyGII) under single and double promoters drive unprecedented sugar contents in sugarcane.

Sugarcane has been grown all around the world to meet sugar demands for industrial sector. The current sugar recovery percentage in sugarcane cultivars is dismally low which demands scientific efforts for improvements. Multiple approaches were adopted to enhance sugar contents in commercial sugarcane plants in contrast to conventional plant breeding methods. The exploitation of biotechnological methods and exploration of isomaltulose synthetic genes presented a promising solution to increase the existing low level of sugar recovery percentage in Saccharum officinarum L. Isomaltulose synthase gene II was employed and integrated into plant expression vector driven under the leaf and stem specific promoters terminated by nopaline synthase gene in a cloning strategy shown in the present study. Three gene constructs were developed in various combinations driven under promoters Zea mays ubiquitin and Cestrum Yellow Leaf Curl virus in the single and double combined stacked system. The transformation was executed in multiple formats with single transformed events, double promoter transformation events and triple construct stacked promoters in sugarcane induced calli via the particle gene gun. The transformation of ImSyGII in sugarcane genotype HSF-240 was confirmed by molecular gene analysis while expression quantification was determined through Real Time PCR. Furthermore, HPLC was also done to harvest the increased amounts of Isomaltulose in transgenic sugarcane juice. The present work upheld the enhanced ImSyGII expression in leaves owing to the exploitation of ubiquitin, while the Cestrum Yellow Leaf Curl virus promoter enhanced gene expression in sugarcane stems. The employment of three gene constructs collectively produced elite sugar lines producing more than 78% enhancements in whole sugar recovery percentage. The mature internode proved highly efficient and receptive regarding the production of isomaltulose. Quantifications and sugar contents evaluations upheld an increased Brix ratio of transgenic sugarcane lines than control lines.

Saccharum↗

PubMed1985

Cariogenicity of isomaltulose (palatinose), sucrose and mixture of these sugars in rats infected with Streptococcus mutans E-49.

Each of three groups of Wistar rats, 19-20 animals per group, was fed an experimental diet containing either (1) isomaltulose 56%, (2) sucrose 56%, or (3) a mixture of isomaltulose and sucrose (17.5% + 38.5%). The animals were infected with Streptococcus mutans E-49 and one half of the animals was kept on the diet for 8 weeks and the other half for 14 weeks. Only sulcal caries was found in the isomaltulose animals after 8 weeks and 14 weeks. the group fed sucrose had high numbers of carious bucco-lingual, proximal and sulcal surfaces. The group fed the mixture of sucrose and isomaltulose had fewer lesions than the sucrose group on bucco-lingual surfaces after the 8 week experiment (P less than 0.01) and fewer bucco-lingual and proximal surfaces (P less than 0.01) after the 14 week experiment.

Animals↗

PubMed2002

13-Week oral toxicity study with isomaltulose (Palatinose) in rats.

The potential subchronic oral toxicity of isomaltulose (Palatinose) was examined by administering this substance in the diet to groups of 20 male and 20 female Wistar rats at levels of 0, 2.5, 5 and 10% for 13 consecutive weeks. Daily clinical observations, body weight, food conversion efficiency, food and water consumption were not affected at any stage of the study. Ophthalmoscopy, haematology, clinical chemistry, urinalysis, organ weights, gross and histopathological examination, neurobehavioural observations, motor activity assessment and the results of an immunotoxicity screen did not reveal any abnormalities related to the ingestion of the test substance. In conclusion, the administration of isomaltulose at dietary levels up to 10% for 13 consecutive weeks was well tolerated without any signs of toxicity. The overall intake at this level corresponded to 7.0 and 8.1 g/kg body weight/day in male and female rats, respectively.

Animals↗

PubMed1984

The extraction and mechanism of a novel isomaltulose-synthesizing enzyme from Erwinia rhapontici.

The single enzyme that mediates the bioconversion is demonstrated to be located in the cells' periplasmic space, a site that facilitates its use as an industrial biocatalyst, and to be a previously undescribed hexosyltransferase with four novel features. The enzyme is sucrose-specific, and has an intramolecular mechanism in which both glucose and fructose residues appear to be enzyme-bound. Thirdly, it is reaction-non-selective, forming simultaneously isomaltulose and a second hitherto uncharacterized alpha-(1----1)-linked disaccharide (trehalulose), by hydrolysis of sucrose followed by reaction of glucose with the C-6 and C-1 positions of the fructofuranose respectively. Finally, on extended incubation an unusual recycling mechanism caused the concentration of isomaltulose, the kinetically preferred product, to reach a transient maximum concentration and then fall, and the concentration of trehalulose, the thermodynamically favoured product, to rise slowly.

Carbohydrate Epimerases↗

PubMed2003

Isomaltulose synthase (PalI) of Klebsiella sp. LX3. Crystal structure and implication of mechanism.

Isomaltulose synthase from Klebsiella sp. LX3 (PalI, EC 5.4.99.11) catalyzes the isomerization of sucrose to produce isomaltulose (alpha-D-glucosylpyranosyl-1,6-D-fructofuranose) and trehalulose (alpha-D-glucosylpyranosyl-1,1-d-fructofuranose). The PalI structure, solved at 2.2-A resolution with an R-factor of 19.4% and Rfree of 24.2%, consists of three domains: an N-terminal catalytic (beta/alpha)8 domain, a subdomain between N beta 3 and N alpha 3, and a C-terminal domain having seven beta-strands. The active site architecture of PalI is identical to that of other glycoside hydrolase family 13 members, suggesting a similar mechanism in substrate binding and hydrolysis. However, a unique RLDRD motif in the proximity of the active site has been identified and shown biochemically to be responsible for sucrose isomerization. A two-step reaction mechanism for hydrolysis and isomerization, which occurs in the same pocket is proposed based on both the structural and biochemical data. Selected C-terminal truncations have been shown to reduce and even abolish the enzyme activity, consistent with the predicted role of the C-terminal residues in the maintenance of enzyme conformation and active site topology.

Amino Acid Sequence↗

PubMed2002

Expression, crystallization and preliminary X-ray analysis of isomaltulose synthase (PalI) from Klebsiella sp. LX3.

Isomaltulose synthase (PalI) catalyzes the hydrolysis of the alpha-1,2 bond between the glucose and fructose moieties of sucrose and the formation of alpha-1,6 and alpha-1,1 bonds between the two components to produce isomaltulose (alpha-D-glucosylpyranosyl-1,6-D-fructofranose) and trehalulose (alpha-D-glucosylpyranosyl-1,1-D-fructofranose), respectively. The PalI protein has been overexpressed, purified and crystallized at 295 K using the hanging-drop vapour-diffusion method. The crystals diffract to 2.2 A resolution using synchrotron radiation and belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 59.239, b = 94.153, c = 111.294 A.

Amino Acid Sequence↗

PubMed2002

Isomaltulose synthase from Klebsiella sp. strain LX3: gene cloning and characterization and engineering of thermostability.

The gene (palI) encoding isomaltulose synthase (PalI) from a soil bacterial isolate, Klebsiella sp. strain LX3, was cloned and characterized. PalI converts sucrose into isomaltulose, trehalulose, and trace amounts of glucose and fructose. Sequence domain analysis showed that PalI contains an alpha-amylase domain and (beta/alpha)(8)-barrel structures, suggesting that it belongs to the alpha-amylase family. Sequence alignment indicated that the five amino acid residues of catalytic importance in alpha-amylases and glucosyltransferases (Asp(241), Glu(295), Asp(369), His(145), and His(368)) are conserved in PalI. Purified recombinant PalI displayed high catalytic efficiency, with a Km of 54.6 +/- 1.7 mM for sucrose, and maximum activity (approximately 328.0 +/- 2.5 U/mg) at pH 6.0 and 35 degrees C. PalI activity was strongly inhibited by Fe3+ and Hg2+ and was enhanced by Mn2+ and Mg2+. The half-life of PalI was 1.8 min at 50 degrees C. Replacement of selected amino acid residues by proline significantly increased the thermostability of PalI. Simultaneous replacement of Glu(498) and Arg(310) with proline resulted in an 11-fold increase in the half-life of PalI at 50 degrees C.

Amino Acid Sequence↗

PubMed1994

Transglucosylation with 6'-chloro-6'-deoxysucrose and immobilized isomaltulose-producing microorganisms using 2,2-dimethyl-1,3-dioxolane-4-methanol and its related compounds as acceptors. Steric and chemical requirement of the glucosyl acceptor.

Enantioselective and diastereoselective alpha-D-glucosylation of 2,3-O-isopropylidene-erythritol was observed in transglucosylation with a synthetic donor using three kinds of immobilized isomaltulose-producing microorganisms. Several related compounds, including an 2,3-O-isopropylidenated aldotetrose dimethyl dithioacetal and an aldotetronic acid ester were also glucosylated in moderate or good yield, depending on the microorganism utilized. Steric as well as functional group factors are discussed in relation to the substrate specificity of the glucosyl acceptor.

Carbohydrate Conformation↗