• 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.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.1
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• pp.59-65
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• 2015

In this study, we evaluated optimum condition of enzyme with pH and temperature for preparation of microfibillated cellulose(MFC). Well-known endo-glucanase, three enzymes were used and CMC was used for substrate. Enzyme activity was evaluated using DNS method and absorbance with UV/VIS spectrophotometer. The enzyme shown the greatest activity was reacted with pulps at optimum condition for 1 hour and treated pulps beated until 100 mL CSF. Enzyme B and Enzyme L was the higher enzyme activity below 0.1% concentration and Enzyme N was the lowest enzyme activity. At various pH and temperature conditions, enzyme activity of Enzyme B was higher than the others at the same concentration. Especially enzyme activity at $50^{\circ}C$ of Enzyme B was almost not changed over pH 6.0. Optimum condition of three enzyme was pH 6 or pH 7 and $50^{\circ}C$ or $60^{\circ}C$. Also beating efficiency of enzyme treated pulps with Enzyme B is 55.6%.

• The Korean Journal of Mycology
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• v.16 no.4
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• pp.214-219
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• 1988

Factors affecting protoplast formation and reversion were investigated in Pleurotus sapidus kalchbr. For release of protoplast, enzyme mixture of Novozyme 234, ${\beta}-D-glucanase$ and ${\beta}-glucuronidase$ was most effective, when mycelium of 0.6 M sucrose solution as osmotic stabilizer without addition of buffer solution. The yield of protoplast was highest with mycelium cultured for 4 days on mushroom complete agar medium at ${30}^{\circ}C$. Protoplasts of Pleurotus sapidus were reverted to normal hyphal growth with maximum reversion frequency of 2% on Mushroom complete agar medium stabilized with 0.6 M sucrose solution and covered by 0.75% agar layer.

• Journal of Microbiology and Biotechnology
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• v.27 no.5
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• pp.896-908
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• 2017

In this study, a total of 58 different kinds of nuruk (a traditional Korean fermentation starter) were prepared, including 46 kinds of restored nuruk from ancient documents. Each nuruk was evaluated by analysis of its saccharification power, and the enzyme activities of glucoamylase, ${\alpha}$-amylase, ${\beta}$-amylase, protease, and ${\beta}$-glucanase. The range of saccharification power (sp) of the restored nuruk ranged between 85 and 565 sp. The diastatic enzymes, ${\alpha}$-amylase, ${\beta}$-amylase, and glucoamylase, were significantly correlated to the saccharification power value; conversely, ${\beta}$-glucanase and protease did not have a correlative relationship with saccarification power. In addition, their brewing properties on chemical and organoleptic aspects of traditional alcoholic beverage production were compared. Each raw and supplementary material contained in nuruk showed its own unique characteristics on Korean alcoholic beverage brewing. For the first time, in this study, the traditional Korean nuruk types mentioned in ancient documents were restored using modernized production methods, and also characterized based on their brewing properties. Our results could be utilized as a basis for further study of traditional alcoholic beverages and their valuable microorganisms.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.81-91
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• 2011

Current fuel ethanol research and development deals with process engineering trends for improving biotechnological production of ethanol. Recently, a large amount of studies regarding the utilization of lignocellulosic biomass as a good feedstock for producing fuel ethanol is being carried out worldwide. The plant biomass is mainly composed of cellulose, hemicellulose and lignin. The main challenge in the conversion of biomass into ethanol is the complex, rigid and harsh structures which require efficient process and cost effective to break down. The isolation of microorganisms is one of the means for obtaining enzymes with properties suitable for industrial applications. For these reasons, crude cultures containing cellulosic biomass degrading microorganisms were isolated from rice field soil, cow farm soil and rotten rice straw from cow farm. Carboxymethyl cellulose (CMC), xylan and Avicel (microcrystalline cellulose) degradation zone of clearance on agar platefrom rice field soil resulted approximately at 25 mm, 24 mm and 22 mm respectively. As for cow farm soil, CMC, xylan and Avicel degradation clearancezone on agar plate resulted around at 24mm, 23mm and 21 mm respectively. Rotten rice straw from cow farm also resulted for CMC, xylan and Avicel degradation zone almost at 24 mm, 23 mm and 22 mm respectively. The objective of this study is to isolatebiomass degrading microbial strains having good efficiency in cellulose hydrolysis and observed the effects of different substrates (CMC, xylan and Avicel) on the production of cellulase enzymes (endo-glucanase, exo-glucanase, cellobiase, xylanase and avicelase) for producing low cost biofuel from cellulosic materials.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.78-82
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• 1993

This study was carried out to develop a new processing method for the production of yeast autolyzate (YA) by which the yield and the quality could be improved, compared to the conventional method. The result indicated that 85.3% of yeast cell walls treated with glucanase and protease was ruptured by homogenizing at 10,000 psi. Alkali treatment, however, was not effective in disintegrating yeast cell walls. Optimum conditions for autolysis of ruptured yeast cells, obtained with help of response surface methodology (RSM), were pH 7.0, $30^{\circ}C$, ethanol 4% and salt 3%. YA produced by the developed method had significantly higher yield and better sensory quality than that produced by the conventional method.

• The Korean Journal of Mycology
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• v.13 no.1
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• pp.1-10
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• 1985

This experiment was undertaken to investigate proper conditions for protoplast isolation from strains of Agaricus bisporus, Flammulina velutipes, Lentinus edodes, Pleurotus florida, Pleurotus ostreatus, Pleurotus sajor-caju and Volvariella volvacea. Combination of ${\beta}-D-glucanase$, novozym 234 and snail enzyme with 0.6M $MgSO_4$ in 0.05M Na-maleate buffer, pH 5.8 was the most effective for isolation of protoplasts. High yields of protoplasts were obtained from $4{\sim}5$ days old mycelia of P. florida and P. ostreatus on mushroom complete agar medium. Protoplasts were also obtained in good yield from other fungi but A. bisporus and V. volvacea. In the latter two cases protoplast release was observed; however, the yield was much lower than those of the other fungi.

• Journal of Microbiology and Biotechnology
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• v.14 no.2
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• pp.430-434
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• 2004

Three extracellular protease-deficient Bacillus subtilis strains were transformed with the plasmid pCK98 containing the endo-$\beta$-1,4-glucanase (Eng) gene of B. subtilis BSE616. The three transformants, B. subtilis DB104 (pCK98), WB600 (pCK98) and WB700 (pCK98), produced the same high level of enzyme activity and showed similar patterns of cell growth and enzyme production. When B. subtilis DB 104 (pCK98), a two-extracellular protease deficient strain, was cultured for 22 h, almost all the secreted enzyme was found to be in the completely cleaved form by both activity staining and Western blotting studies. B. subtilis WB600 (pCK98), a six-extracellular protease-deficient strain, produced a partially cleaved form in addition to the intact form of the enzyme, although the degree of internal cleavage of the enzyme was greatly reduced. With B. subtilis WB700 (pCK98), a seven-extracellular protease-deficient strain, almost all the enzyme was produced as the intact uncleaved form. This study illustrates that a role of the V pr protease is to degrade foreign proteins produced in B. subtilis and WB700 is a suitable expression system for producing the intact form of the Eng and other foreign proteins that may lose at least part of their efficacy due to internal proteolytic cleavage.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.407-415
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• 2012

An endophytic bacterium, Bacillus thuringiensis GS1, was isolated from bracken (Pteridium aquilinum) and found to have maximal production of chitinase (4.3 units/ml) at 5 days after culture. This study investigated the ability of B. thuringiensis GS1 to induce resistance to Rhizoctonia solani KACC 40111 (RS) in cucumber plants. Chitinase activity was greatest in RS-treated plants at 4 days. ${\beta}$-1,3-Glucanase activity was highest in GS1-treated plants at 5 days. Guaiacol peroxidase (GPOD) activity increased continuously in all treated plants for 5 days. Ascorbate peroxidase (APX) activity in RS-treated plants was increased 1.5-fold compared with the control at 4 days. Polyphenol oxidase (PPO) activity in RS-treated plants was increased 1.5-fold compared with the control at 3 days. At 5 days after treatment, activity staining revealed three bands with chitinase activity (Ch1, Ch2, and Ch3) on SDS-PAGE of cucumber plants treated with GS1+RS, whereas only one band was observed for RS-treated plants (Ch2). One GPOD isozyme (Gp1) was also observed in response to treatment with RS and GS1+RS at 4 days. One APX band (Ap2) was present on the native-PAGE gel of the control, and GS1- and GS1+RS-treated plants at 1 day. PPO bands (Po1 and Po2) from RS- and GS1+RS-treated plants were stronger than in the control and GS1-treated plants upon native-PAGE at 5 days. Taken together, these results indicate that the induction of PR proteins and defense-related enzymes by B. thuringiensis GS1 might have suppressed the damping-off caused by R. solani KACC 40111 in cucumber plants.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.346-356
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• 2011

BACKGROUND: Chemical fungicides not only may pollute the ecosystem but also can be environmentally hazardous, as the chemicals accumulate in soil. Biological control is a frequently-used environment-friendly alternative to chemical pesticides in phytopathogen management. However, the use of microbial products as fungicides has limitations. This study isolated and characterized a three-antifungal-enzyme (chitinase, cellulase, and ${\beta}$-1,3-glucanase)-producing bacterium, and examined the conditions required to optimize the production of the antifungal enzymes. METHOD AND RESULTS: The antifungal enzymes chitinase, cellulase, and ${\beta}$-1,3-glucanase were produced by bacteria isolated from an sawmill in Korea. Based on the 16S ribosomal DNA sequence analysis, the bacterial strain AM50 was identical to Streptomyces sp. And their antifungal activity was optimized when Streptomyces sp. AM50 was grown aerobically in a medium composed of 0.4% chitin, 0.4% starch, 0.2% ammonium sulfate, 0.11% $Na_2HPO_4$, 0.07% $KH_2PO_4$, 0.0001% $MgSO_4$, and 0.0001% $MnSO_4$ at $30^{\circ}C$. A culture broth of Streptomyces sp. AM50 showed antifungal activity towards the hyphae of plant pathogenic fungi, including hyphae swelling and lysis in P. capsici, factors that may contribute to its suppression of plant pathogenic fungi. CONCLUSION(S): This study demonstrated the multiantifungal enzyme production by Streptomyces sp. AM50 for the biological control of major plant pathogens. Further studies will investigate the synergistic effect, to the growth regulations by biogenic amines and antifungal enzyme gene promoter.