• Korean Journal of Microbiology
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• v.51 no.1
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• pp.68-74
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• 2015

Based on the genomic analysis of Thermococcus pacificus P-4, we identified a putative GH1 ${\beta}$-glucosidase-encoding gene (Tpa-glu). The gene revealed a 1,464 bp encoding 487 amino acid residues, and the deduced amino acid residues exhibited 77% identity with Pyrococcus furiosus ${\beta}$-glucosidase (accession no. NP_577802). The gene was cloned and expressed in Escherichia coli system. The recombinant protein was purified by metal affinity chromatography and characterized. Tpa-Glu showed optimum activity at pH 7.5 and $75^{\circ}C$, and thermostability with a half life of 6 h at $90^{\circ}C$. Tpa-Glu exhibited hydrolyzing activity against various pNP-glycopyranosides, with kcat/Km values in the order of pNP-${\beta}$-glucopyranoside, pNP-${\beta}$-galactopyranoside, pNP-${\beta}$-mannopyranoside, and pNP-${\beta}$-xylopyranoside. In addition, the enzyme exhibited exo-hydrolyzing activity toward ${\beta}$-1,3-linked polysaccharide (laminarin) and ${\beta}$-1,3- and ${\beta}$-1,4-linked oligosaccharides. This is the first description of an enzyme from hyperthermophilic archaea that displays exo-hydrolyzing activity toward ${\beta}$-1,3-linked polysaccharides and could be applied in combination with ${\beta}$-1,3-endoglucanase for saccharification of laminarin.

• Korean journal of food and cookery science
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• v.15 no.1
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• pp.50-54
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• 1999

The persimmon puree was hydrolyzed with commercial polysaccharide hydrolyzing enzymes, Viscozyme and Celluclast and jam was prepared with the enzyme treated persimmon juice by addition of pectin. The textural characteristics of the jam were studied for the effects of pectin addition and storage temperature. When the persimmon jam was prepared with the enzyme treated juice with addition of pectin(2.2∼3.0%), the hardness of the go] was stabilized at the addition level of more than 2.8% as measured by %sag. The hardness, cohesiveness, adhesiveness, and gumminess were also significantly increased as the amount of pectin addition increased, whereas the cohesiveness and elasticity did not change significantly. The gel prepared with the puree hydrolyzed with Celluclast generally showed higher hardness, gumminess and adhesiveness and less cohesiveness and elasticity than those treated with Viscozyme. Higher temperature (17$^{\circ}C$) caused a significant decrease in most of the textural properties except elasticity. Results of sensory test showed the orange colors was much improved by the Celluclast treatment, while other characteristics such as total acceptability and texture were not significantly different.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.198-203
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• 1997

The ground persimmon puree was treated with two kinds of commercial polysaccharide hydrolyzing enzymes (Viscozyme and Celluclast) in order to study their effects on the extraction yield, viscosity, color, titratable acidity and sugars. Hydrolysis with Viscozyme which has enzymatic activity of arabinase, cellulase, xylanase, hemicellulase and ${\beta}-glucanase$ significantly increased the extraction yield, L-value and reducing sugar and decreased in viscosity by treatment for 10 min at $50^{\circ}C$. The extraction yield of the juice was increased from 42.7% to 80% by Viscozyme while the Celluclast to 73.3%. On the other hand, the sensory properties of persimmon-like flavor, scarlet and orange color were greatly improved for the juice hydrolyzed with Viscozyme for 60 min.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.46-52
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• 1996

Effective method for the preparation of Dongchimi juice was developed by addition of NaCi, sucrose and bydrolytic enzymes before fermentation and addition on Dongchimi juice during fermentation. The radish was ground and suspended in water(1:1, w/v) with addition of spices(garlic, green onion and ginger) followed by fermentation at $25^{\circ}C$. The addition of 2% NaCi and 0.5~2.0% sucrose resulted in significant increase of solid content and it was also improved by the addition of polysaccharide hydrolyzing enzyme during fermentation. When the fermented juices of pH 5.4 of 4.4 were added by 15% of total weight before(pH 5.4 juice)and during (pH 4.4 juice) fermentation, a significant increase in solid content after 24hrs of fermentation was resulted. The combined method of addition of 2% NaCI, 1.0% sucrode, 0.1% Viscozyme and 10% of fermented juice of pH 5.4 and 4.$ before and during fermentation improved solid content, reducing sugar, color and showed little effect on viscosity. The organoleptic characteristics were also improved by the combined method.