• Applied Biological Chemistry
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• v.47 no.4
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• pp.384-389
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• 2004

The purified ${\beta}-mannanase$ hydrolyzed various gums to mannose, ${\beta}-1,4-mannobiose$, $Gal^3Man_4$, and D.P 7 of galactosyl mannooligosaccharide, and isolated from the enzymatic hydrolysate for 24 hrs reaction by activated carbon column chromatography and Sephadex G-25 column chromatography. For the elucidate of antioxidant action of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ and DP 7 of galactosyl mannooligosaccharide and urea derivatives, coloration, reducing power, antioxidant activity and DPPH test were accomplished. The coloration was high at reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and urea. TLC of reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and ureas showed new reaction products, respectively. but except reaction mixture of ${\beta}-1,4-mannobiose$ and urea. The reducing power was high at reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and phenylthiourea. The reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and thiourea showed similar radical scavenging activities on DPPH to activity of AsA. The reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and thiourea, phenythiolurea shown strong antioxidative activites on the oxidation of linoneic acid.

• Journal of Microbiology and Biotechnology
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• v.3 no.3
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• pp.194-198
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• 1993

${\beta}-1$, 4-Mannobiose was prepared by the enzymatic hydrolysis of brown copra meal and the subsequent elimination of mono-saccharides from the resultant hydrolysate with a yeast. The enzyme system hydrolyzed brown copra meal and produced monosaccharides and $\beta$-1, 4-mannobiose without other oligomers at the final stage of the reaction. Brown copra meal (30 g) was hydrolyzed at $50^{\circ}^C$ and pH 5 for 48 hr with the crude enzyme solution (300 ml) from Penicillium purpurogenum. By the elimination of monosaccharides from the hydrolysis products with a yeast (Candida parapsilosis var. komabaensis k-75), 5.2 g of crystalline mannobiose was obtained without the use of chromatographic techniques. After 50 hours of yeast cultivation, the total sugar content fell from 3.5% to 2.4%, and the average degree of polymerization rose from 1.8 to 2.2.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.1020-1025
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• 1995

A new method was developed to prepare ${\beta}-1$, 4-mannotriose by the enzymatic hydrolysis of white copra meal and the subsequent elimination of monosaccharides and mannobiose from the resulted hydrolysate with a yeast. The optimum pH and temperature for the mannanase were 6 and $50^{\circ}C$, respectively. The mannanase was stable between pH 5.5 and 7 after 2hr treatment at $30^{\circ}C$. White copra meal(70g) was hgydrolyzed with the mannanase(3,450units/500ml) at pH 6 and $50^{\circ}C$ for 24hr. The hydolysis products were monosaccharides, mannobiose and mannotriose. By the elimination of monosaccharides and mannobiose from the hydrolysis products with Candida guilliermondii IFO 0556, 12.1g of mannotriose was obtained without the use of chromatographic techiniques.

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.347-351
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• 2004

Hydrolysis of manno-oligosaccharides and galactomannan was studied with the purified Bacillus subtilis WL-7 mannanase from recombinant Eschericoli. The predominant products of hydrolysis were mannose, mannobiose and mannotriose. The enzyme could hydrolyze $\beta$-1 A-linked manno-oligosaccharides larger than mannobiose, but was not active on mannobiose. When the mannanase hydrolyzed manno-oligo saccharides of degree of polymerization(DP) 4-6, it was more active on the substrate of higher DP. Based on analysis of transient reaction products by TLC, the enzyme was found to have a preference for internal $\beta$-IA-mannosidic linkages, which are the central mannosidic bond of mannotetraose and the two middle mannosidic bonds of mannopentaose. The $\beta$-l A-mannosidic bonds situated at the second and fourth positions from the nonreducing end of mannohexaose were preferenhydrolyzed by the mannanase. Locust bean gum(LBG) was enzymatically hydrolyzed with higher efficiency than guar gum, resulting that amount of reducing sugars was liberated more efficiently from LBG than guar gum with same activity of mannanase.

• Korean Journal of Microbiology
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• v.46 no.4
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• pp.397-400
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• 2010

The activities of mannanase, ${\beta}$-mannosidase, and ${\alpha}$-galactosidase were detected in culture filtrate of Paenibacillus woosongensis showing mannanolytic activity for locust bean gum. Optimal conditions occurred at pH 5.5 and $60^{\circ}C$ for mannanase toward locust bean gum, pH 6.5 and $50^{\circ}C$ for ${\beta}$-mannosidase toward para-nitrophenyl-${\beta}$-D-mannopyranoside, and pH 6.0-6.5 and $50^{\circ}C$ for ${\alpha}$-galactosidase toward para-nitrophenyl-${\alpha}$-D-galactopyranoside in the culture filtrate, respectively. The mannanolytic enzyme of culture filtrate hydrolyzed mannobiose as well as manno-oligosaccharides including mannotriose, mannotetraose, mannopentaose and mannohexaose. It could also hydrolyze ${\alpha}$-1,6 linked galacto-oligosaccharides such as melibiose, raffinose and stachyose to liberate galactose residue. From these results, it is assumed that P. woosongensis produces three enzymes required for the complete decomposition of galactomannan.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.336-343
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• 2016

A mannanase gene was cloned into Escherichia coli from Cellulosimicrobium sp. YB-43, which had been found to produce two kinds of mannanase, and sequenced completely. This mannanase gene, designated manB, consisted of 1,284 nucleotides encoding a polypeptide of 427 amino acid residues. Based on the deduced amino acid sequence, the ManB was identified to be a modular enzyme including two carbohydrate binding domains besides the catalytic domain, which was highly homologous to mannanases belonging to the glycosyl hydrolase family 5. The N-terminal amino acid sequence of ManB, purified from a cell-free extract of the recombinant E. coli carrying a Cellulosimicrobium sp. YB-43 manB gene, has been determined as QGASAASDG, which was correctly corresponding to signal peptide predicted by SignalP4.1 server for Gram-negative bacteria. The purified ManB had a pH optimum for its activity at pH 6.5~7.0 and a temperature optimum at $55^{\circ}C$. The enzyme was active on locust bean gum (LBG), konjac and guar gum, while it did not exhibit activity towards carboxymethylcellulose, xylan, starch, and para-nitrophenyl-${\beta}$-mannopyranoside. The activity of enzyme was inhibited very slightly by $Mg^{2+}$, $K^+$, and $Na^+$, and significantly inhibited by $Cu^{2+}$, $Zn^{2+}$, $Mn^{2+}$, and SDS. The enzyme could hydrolyze mannooligosaccharides larger than mannobiose, which was the most predominant product resulting from the ManB hydrolysis for mannooligosaccharides and LBG.

• Journal of Korean Society of Transportation
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• v.23 no.7 s.85
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• pp.165-179
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• 2005

The object of this study is a development of a stochastic user equilibrium transit assignment algorithm for multiple user classes considering stochastic characteristics and heterogeneous attributes of passengers. The existing transit assignment algorithms have limits to attain realistic results because they assume a characteristic of passengers to be equal. Although one group with transit information and the other group without it have different trip patterns, the past studies could not explain the differences. For overcoming the problems, we use following methods. First, we apply a stochastic transit assignment model to obtain the difference of the perceived travel cost between passengers and apply a multiple user class assignment model to obtain the heterogeneous qualify of groups to get realistic results. Second, we assume that person trips have influence on the travel cost function in the development of model. Third, we use a C-logit model for solving IIA(independence of irrelevant alternatives) problems. According to repetition assigned trips and equivalent path cost have difference by each group and each path. The result comes close to stochastic user equilibrium and converging speed is very fast. The algorithm of this study is expected to make good use of evaluation tools in the transit policies by applying heterogeneous attributes and OD data.