• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.11-18
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• 1994

We have studied the iron uptake by the purified brush-border membrane vesicles (BBMVs) to determine the effect of fructose on the absorption of iron. BBMVs were prepared by the modified calcium precipitation method, The degree of purification was routinely assessed by the marker enzyme, alkaline phosphatase, and the functional integrity was tested by $D-[1-^3H]glucose$ uptake. The appearance of membrane vesicles was shown by transmission electron microscopy (TEM). The uptakes of complexes of labeled iron $[^{59}Fe]$ with fructose and ascorbate were measured with a rapid filtration technique, The uptake rate and pattern of the two iron-complexes, Fe(III)-fructose and Fe(III)-ascorbate, were also observed. A typical overshooting uptake of D-glucose was observed with peak value of $2{\sim}3$ times higher concentration than that at equilibrium. This result was similar to other studies with BBMVs. TEM showed that the size of BBMVs was uniform and we can hardly find any contaminants, Fe(III)-fructose has the higher value of $V_{max}$ and the lower value of Km than those of Fe(III)-ascorbate, respectively. It may be concluded that D-fructose is more effective in promoting the iron absorption than ascorbate.

• Journal of Magnetics
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• v.17 no.4
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• pp.271-274
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• 2012

We examine dosimetry application of irradiated D-fructose materials using electron paramagnetic resonance (EPR). Consequently, we consider that fructose is one of best dosimetry materials. We found that fructose is one of best candidates for dosimetry due to high linearity tilt of EPR signal intensity as a function of dose, irrelevant to photon energy, constant fading value. Also, our results show that fructose materials can be applied as a radiation detector to very weak radiation doses of 0.001 Gray by using EPR at a low temperature (T = 220 K).

• Molecules and Cells
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• v.40 no.10
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• pp.731-736
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• 2017

Taste sensitivity to sugars plays an essential role in the initiation of feeding behavior. In Drosophila melanogaster, recent studies have identified several gustatory receptor (Gr) genes required for sensing sweet compounds. However, it is as yet undetermined how these GRs function as taste receptors tuned to a wide range of sugars. Among sugars, fructose has been suggested to be detected by a distinct receptor from other sugars. While GR43A has been reported to sense fructose in the brain, it is not expressed in labellar gustatory receptor neurons that show taste response to fructose. In contrast, the Gr64a-Gr64f gene cluster was recently shown to be associated with fructose sensitivity. Here we sought to decipher the genes required for fructose response among Gr64a-Gr64f genes. Unexpectedly, the qPCR analyses for these genes show that labellar expression levels of Gr64d and Gr64e are higher in fructose low-sensitivity flies than in high-sensitivity flies. Moreover, gustatory nerve responses to fructose in labellar sensilla are higher in Gr64d and Gr64f mutant lines than in mutant flies of the other Gr64a-Gr64f genes. These data suggest the possibility that deletion of GR64D or GR64F may indirectly induce enhanced fructose sensitivity in the labellum. Finally, we conclude that response to fructose cannot be explained by a single one of the Gr64a-Gr64f genes.

• Microbiology and Biotechnology Letters
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• v.9 no.1
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• pp.45-50
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• 1981

The effect of growth and the carbon sources including the molar ratio of fructose to glucose was studied for the maximization of inosine-5'-monophosphate (5'-IMP) production from Brebibacterium ammoniagenes D-21530. According to experimental results, fructose was more efficient to 5'-IMP accumulation than glucose, while the latter was better for the cell growth than the former. To synchronously use glucose and fructose as carbon source is to optimally control the cell growth and maximum production of 5'-IMP without change of other conditions. The optimal weight percent of fructose to sum of glucose and fructose was 20～40%, and the productivity improvement over the utilization of fructose was about 40%. And also the optimality of purine base such as adenine and guanine were considered. The optimal concentrations of adenine and guanine were near 50㎎/l.

• Korean Journal of Microbiology
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• v.35 no.2
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• pp.146-152
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• 1999

Acceplor reaction of glucosyltr~ansferase of Streptococcus ,SO~~-~IZLIS with f ~ ~ t o ~ y l o l i g o ~ a ~ ~ h a r i d e ~ was studied for the biosynthesis of novel olgisaccharides. First, bacilracin resistant mutants were selected by mutagenesis of Streptococcus sobrimis ATCC27351. Among these mutants 4 strains were selected by resistance to bacitracin and increase of glucosyltransferase. Acceptor reaction of maltose was analyzed by TLC and image analysis. There were differences in the specificity of the acceptor reaclion by Ule glucosylumsferase between mother strain (Streptococcus sobrinus ATCC2735) and bacitracin resistant mutants (Streptococcus sobrinus BR24C, Strepfococcus sobrinus CH-5). Molher strain did ilot show an acceptor reaction with fructosyloligosaccharides such as 1-keqtose and nystose. Acceptor reaction products of turailose and 1-kestose with glucosyltransferase (GW-S) of Streptococcus sobrini~s BR24C were TEX>\6^{3}$-$\alpha$-D-glucopyranosyl \3^{2}$-O-$\alpha$-D-fructose (glucose-fructose-glucose) and \6^{4}$-$\alpha$-D-glucopyranosyl \1^{3}$-$\beta$-D-~-h~ctofuranos~~ sucrose (glucose-glucosefructose- fructose). respectively These are novel oligosaccharides which can be produced only by enzymatic reaction.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.1
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• pp.27-34
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• 2013

Quantitative analysis of 5-hydroxymethylfufural (5-HMF) conversion from fructose by dehydration and rearrangement was investigated by $^1H$-NMR spectroscopic method. Fructose was converted to 5-HMF in dimethylsulfoxide (DMSO)-$d^6$ or acidic deuterium hydroxide at controlled reaction temperature and time. With addition of internal standards (biphenyl for DMSO-$d^6$ solvent, and 2,5-dihydroxybenzoic acid for deuterium oxide solvent), conversion from fructose to 5-HMF was analyzed by $^1H$-NMR spectroscopy. Quantitative analysis was run by comparison with peak area integration between of 5-HMF and internal standard. In DMSO solvent, 5-HMF was stable end product but part of 5-HMF was converted to formic and levulinic acid at acidic aqueous medium.

• Preventive Nutrition and Food Science
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• v.13 no.2
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• pp.134-137
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• 2008

This study was conducted to investigate the effect of pH on the formation of acrylamide and acrylate from glucose and fructose reacting with amino acid enantiomers by the Maillard reaction. The acrylamide content was increased with increasing pH, except for Fru/D-Asn system. Both acrylamide and acrylate contents were higher in the glucose-based system compared to the fructose-based system at pH 10.0. However, according to amino acid enantiomers, only the acrylamide content showed a difference in the fructose-based system. In addition, the acrylate content was increased with increasing pH except in the Glc/L-Asn system. Acrylate formation was observed specifically at pH 4.0 for both the Glc/D-Asn and Fru/D-Asn systems.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.418-424
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• 2018

${\text\tiny{D}}-Allose$ is a potential medical sugar because it has anticancer, antihypertensive, antiinflammatory, antioxidative, and immunosuppressant activities. Allose production from fructose as a cheap substrate was performed by a one-pot reaction using Flavonifractor plautii ${\text\tiny{D}}-allulose$ 3-epimerase (FP-DAE) and Clostridium thermocellum ribose 5-phosphate isomerase (CT-RPI). The optimal reaction conditions for allose production were pH 7.5, $60^{\circ}C$, 0.1 g/l FP-DAE, 12 g/l CT-RPI, and 600 g/l fructose in the presence of 1 mM $Co^{2+}$. Under these optimized conditions, FP-DAE and CT-RPI produced 79 g/l allose for 2 h, with a conversion yield of 13%. This is the first biotransformation of fructose to allose by a two-enzyme system. The production of allose by a one-pot reaction using FP-DAE and CT-RPI was 1.3-fold higher than that by a two-step reaction using the two enzymes.

• Journal of Plant Biotechnology
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• v.31 no.2
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• pp.169-173
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• 2004

Parenchyma cells of Streptanthus tortus suspension cultures possessed the different transport system for aldose-formed D-glucose and for ketose-formed D-fructose. $K_{m}$ value for D-glucose and D-fructose were 0.28mM and 15.02mM, respectively. $K_{m}$ value of D-mannose was 0.44 mM which is similar to the D-glucose transport system, but D-mannose was transported also through its own special uptake system. Parenchyma cells possessed the transport system of L-glucose, but the function of L-glucose was not known at all. Protoplast of parenchyma cells possessed only the monosugars transport system, but didn't possess the disugars, sucrose transport system. Early developing phloem protoplasts possessed glucose and sucrose transport system at the same time. On the contrary, in the complete developed phloem cells disappeared preexisted glucose transport system in the parenchyma cells, only new induced sucrose transport system existed.ted.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.675-683
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• 2016

One osmotolerant strain from among 44 yeast isolates was selected based on its growth abilities in media containing high concentrations of sucrose. This selected strain, named SK-ENNY, was identified as Meyerozyma guilliermondii by sequencing the internal transcribed spacer regions and partial D1/D2 large-subunit domains of the 26S ribosomal RNA. SK-ENNY was utilized to produce high-fructose glucose syrup (HFGS) from sucrose-containing biomass. Conversion rates to HFGS from 310-610 g/l of pure sucrose and from 75-310 g/l of sugar beet molasses were 73.5-94.1% and 76.2-91.1%, respectively. In the syrups produced, fructose yields were 89.4-100% and 96.5-100% and glucose yields were 57.6-82.5% and 55.3-79.5% of the theoretical values for pure sucrose and molasses sugars, respectively. This is the first report of employing M. guilliermondii for production of HFGS from sucrose-containing biomass.