• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.370-374
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• 1997

Commercial Sikhye was fermented by Saccharomyces cerevisiae for 10 day at 29$^{\circ}C$. Sucrose was hydrolyzed into glucose and fructose by invertase from the yeast, and the glucose and fructose were converted into ethanol by the yeast. Commercial Sikhye wine was found to contain 6.6% of ethanol, 0.32$\mu$mol/ml of amino acid, 226$\mu\textrm{g}$/ml of protein, and 2.5ml 0.1N NaOH of acidity, respectively, and its pH was 3.21. Limit dextrin in commercial rice Sikhye wine showed both signal of $\alpha$-1, 4- and $\alpha$-1, 6- glucosidic linkage with its estimation ratio of 25:1 by 1H-NMR analysis. The taste of rice Sikhye wine was similar that of wine.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.360-364
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• 1997

Rice Sikhye was fermented by Saccharomyces cerevisiae for 10 day at 29$^{\circ}C$. Fermentable sugars such as glucose, maltose and maltotriose in rice Sikhye were converted into ethanol by the yeast, but limit dextrin was remained after the fermentation. Rice Sikhye wine was found to contain 5.3% of limit dextrin, 6.5% of ethanol, 2.9 $\mu$mol/ml of amino acid, 457$\mu\textrm{g}$/ml of protein, and the acidity of the Sikhye showed 3.1, respectively, and its pH was 3.67. Limit dextrin in rice Sikhye wine showed both signal of $\alpha$-1,4- and $\alpha$-1,6-glucosidic linkage wit its estimation ratio of 5.6:1 by 1H-NMR analysis. The taste of rice Sikhye wine was similar that of wine.

• Microbiology and Biotechnology Letters
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• v.17 no.1
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• pp.1-7
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• 1989

To enhance the capability of starch fermentation of the transformant TSD-14, the heat treated protoplasts of TSD-14 were fused with the protoplasts of C. tropicalis (lys$^-$) in the presence of 30% (w/ v) PEG and 20 mM CaC1$_2$. Fusants were selected by nutritional complementation on minium medium and the fusion frequency was 4.4$\times$10$^{-5}$. All fusants tested were possessed of complemented traits concerning carbon compound assimilation, and the cell volumes of the fusants were approximately 1.5 times larger than the parental strains. The fusants were genetically very stable, and were able to hydrolyze alpha 1,4-glucosidic linkage as well as alpha 1,6-linkage of starch contrary to one of parents TSD-14, The most promising fusant FSC-14-75 produced 8.7% (v/v) of ethanol from 15% liquefied potato starch medium, but the result was enhanced to 9.3% (v/v) by addition of 0.3% peptone. The corresponding fermentation efficiency was 86.0%.

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1347-1353
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• 2005

Sets of sialic acid-containing trisaccharides having different internal and terminal linkages have been synthesized to develop a sensitive method for analysis of the reducing terminal linkage positions. The trisaccharides, sialyl($\alpha$ 2-3)Gal($\beta$ 1-3)GalNAc and sialyl($\alpha$ 2-3)Gal($\beta$ 1-X)GlcNAc where X=3, 4 and 6, were synthesized and examined using electrospray ionization (ESI)-collision induced dissociation (CID) tandem mass spectrometry (MS/MS). The compounds chosen for this study are related to terminal groups likely to be found on polylactosamine-like glycoproteins and glycolipids which occur on the surface of mammalian cells. The purpose of this study is to develop tandem mass spectrometral methods to determine detailed carbohydrate structures on permethylated or partially methylated oligosaccharides for future applications on biologically active glycoconjugates and to exploit a faster method of synthesizing a series of structural isomeric oligosaccharides to be used for further mass spectrometry and instrumental analysis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.5
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• pp.516-521
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• 2014

A bacterium producing ${\alpha}$-galactosidase (${\alpha}$-$\small{D}$-galactoside galactohydrolase, EC 3.2.1.22) was isolated. The isolate, KM-1 was identified as Bacillus coagulans based on its 16S rRNA sequence, morphology, and biochemical properties. ${\alpha}$-Galactosidase activity was detected the culture supernatant of B. coagulans KM-1. The bacterium showed the maximum activity for hydrolyzing para-nitrophenyl-${\alpha}$-$\small{D}$-galactopyranoside (pNP-${\alpha}Gal$) at pH 6.0 and $50^{\circ}C$. It hydrolyzed oligomeric substrates such as melibiose, raffinose, and stachyose liberating a galactose residue, indicating that the B. coagulans KM-1 ${\alpha}$-galactosidase hydrolyzed ${\alpha}$-1,6 linkage. The results suggest that the decreased stachyose and raffinose contents in fermented soybean meal are due to the ${\alpha}$-galactosidase activity.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.150-158
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• 1998

Limit dextrin of Korean beer(3 brands) and Japanese beer(21 brands) were separated by ethanol fractionation. Limit dextrin of Korean and Japanese beer was estimated to be 1.1%. 1H-NMR analysis revealed that the limit dextrin showed both signal of $\alpha$-1, 4- and $\alpha$-1, 6- glucosidic linkage with its estimation ratio of average 5.5:1. Limit dextrin was hydrolyzed to glucose with the yield of 57.22% by Aspergillus awamori $\alpha$-glucosidase(24.7 unit) plus human salivay $\alpha$-amylase(2.4 unit) in 100${mu}ell$ of 0.043M acetate buffer at 37$^{\circ}C$ for 5 hour. Among them, limit dextrin of Korean beer showed the highest hydrolysis rate of 76%. Small size sugars (64.8%) removed by ethanol fractionation and limit dextrin(21.4%) hydrolyzed by amylases that is digestable sugar. Non hydrolyzed limit dextrin(13.8%) by the amylases which can be a growth factor of Bifidobacterium in human intestine.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.309-313
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• 1997

Bench scale Sikhyes were produced from rice and glutinous rice and limit dextrins in rice Sikhye and glutinous rice Sikhye were purified by ethanol precipitation and Biogel P-2 gel chromatography and FPLC on Superose 12 column and analyzed. The purified limit dextrin in rice Sikhye and glutinous rice Sikhye showed bot signal of $\alpha$-1,4- and $\alpha$-1,6-glucosidic linkage with its estimation ratio of 4.5:1 and 5.9:1, respectively, by 1H-NMR analysis. Limit dextrins were hydrolyzed by pullulanase. The enzyme hydrolysis products contained maltose, maltotriose, maltotetraose, maltopentaose and matohexaose. These results suggest that limit dextrins were composed of these maltoolgosaccharide series with $\alpha$-1,6-glucosidic bond.

• Applied Biological Chemistry
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• v.13 no.3
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• pp.181-186
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• 1970

1) Conditions for the hydrolysis of starch by bacterial liquefying amylase (BLA), saccharifying amylase (BSA) and isoamylase were investigated. Out of four syrups prepared by different combinations of these enzymes, those made by BLA followed by BSA and/or isoamylase were comparable to sucrose syrup in canning of orange segments. 2) Two branched maltooligosaccharides were isolated from the hydrolyzate of starch by BLA and BSA, and their structures were tentatively identified as pentaose and hexaose having an ${\alpha}-1$, 6-linkage at the branching point.

• The Korean Journal of Food And Nutrition
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• v.10 no.4
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• pp.446-452
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• 1997

Sugars in Korean Kochuzang, saccharified and fermented red pepper paste, were studied by HPLC, TLC and NMR. The sugars in Kochuzang were extracted by heating in boiling water bath for 3 min. Commercial Kochuzang was found to contain 0.8~6.5% of limit dextrin, 0.3~7.3% of maltotriose, 5.3~16.5% of maltose, 8.6~29.4% of glucose and 0.3~3.4% of fructose, but did not found sucrose. The sugars in domestic Kochuzang were found to contain 2.3~1.5% of limit dextrin, 3.3~6.9% of maltotriose, 6.1~11.5% of maltose, 6.1~11.7% of glucose and 3.4~5.2% of fructose and 3.6~3.8% of sucrose. Limit dextrin in Kochuzang of maker 1 and 3 showed both signal of $\alpha$-1, 4- and $\alpha$-1, 6-glucosidic linkage with its estimation ratio of 5:1 and 9.1:1, respectively, by 1H-NMR analysis.

• Journal of Microbiology and Biotechnology
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• v.21 no.5
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• pp.449-454
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• 2011

The infection of pandemic influenza viruses such as swine flu (H1N1) and avian flu viruses to the host cells is related to the following two factors: First, the surface protein such as HA (hemagglutinin) and NA (neuraminidase) of the influenza virus. Second, the specific structure of the oligosaccharide [sialic acid(${\alpha}2$-6) galactose(${\beta}1$-4)glucose or sialic acid(${\alpha}2$-3)galactose(${\beta}1$-4)glucose] on the host cell. After recognizing the specific structure of the oligosaccharide on the surface of host cells by the surface protein of the influenza virus, the influenza virus can secrete sialidase and cleave the sialic acid attached on the final position of the specific structure of the oligosaccharide on the surface of host cells. Tamiflu (oseltamivir), known as a remedy of swine flu, has a saccharide analog structure, especially the sialic acid analog. Tamiflu can inhibit the invasion of influenza viruses (swine flu and avian flu viruses) into the host cells by competition with sialic acid on the terminal position of the specific oligosaccharide on the surface of the host cell. Because of the emergence of Tamiflu resistance, the development of new potent anti-influenza inhibitors is needed. The inhibitors with positive-charge groups have potential as antiviral therapeutics, and the strain specificity must also be resolved.