• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.240-245
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• 1993

The optimum pH and temperature for the purified extracellular enzyme activity were 8.0 and 37$^{\circ}C$, respectively. NaCl was required for the activation of the enzyme and optimum concentration was 0.5M. This enzyme activity was inhibited by HgC $l_2$, CoC $l_2$ and ZnC $l_2$ and stimulated by CaC $l_2$. The activity of enzyme was increased by L-cysteine and 2-mercaptoethanol, but decreased by ο-phenanthroline, $\rho$-CMB, EDTA and iodoacetate. The $K_{m}$ and $V_{max}$ values of extracellular enzyme appeared as 0.717% and 15.39U/mg, respectively.y.

• Journal of Korean Society of Forest Science
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• v.105 no.2
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• pp.261-267
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• 2016

In this study, the cellulase of Monochamus saltuarius (MsGHF45) gene was introduced in Kluyveromyces lactis, successfully. The molecular weight of recombinant enzyme was determined by SDS-PAGE and western blotting. The enzymatic activity was confirmed by native-PAGE containing carboxymethyl cellulose as a substrate. The optimul pH and temperature of recombinant MsGHF45 was pH5 and $40^{\circ}C$. The barium ($Ba^{2+}$) and ferrous ($Fe^{2+}$) enhanced enzyme activity, and the mercuty ($Hg^{2+}$) inhibited its activity.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.2
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• pp.73-82
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• 1999

To verify the usefulness of enzyme activity as a index for the stability or maturity of apple pomace composting. the succession of microbial populations using viable count procedure. and Vmax of ${\beta}$-glucosidase and cellobiohydrolase were measured. based on an increase in fluorescence as the nonfluorescent methylumbelliferyl substrates were enzymatically hydrolyzed, leading to the highly fluorescent methylumbelliferyl molecule 4-methylumbelliferone(MUF). The activities of these enzymes in the decomposition of carbohydrates were gradually decreased in the course of the time. Correlation between microbial population and enzyme activity was not significant with exception of fungi. and the fungi were represented in high density. This indicates that the fungi probably play a major role in composting of apple pomace.

• Microbiology and Biotechnology Letters
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• v.44 no.1
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• pp.98-105
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• 2016

The presence of bacterial strains showing antagonistic activity to common pathogens found in a variety of fermented foods in Korea was explored. A bacterium inhibiting the growth of pathogens such as Aspergillus terreus (KCTC6178), A. flavus (KCTC6984), Staphylococcus aureus (KCCM12214), Escherichia coli O157:H7 (KCCM40406), Bacillus cereus (KCTC1012), Cryptococcus neoformans (ATCC208821), Salmonella typhimurium (ATCC19430), and Listeria monocytogenes (KCTC3569) was isolated from Makgeolli, a Korean traditional rice wine. The strain showing high antipathogenic activity was identified as B. amyloliquefaciens based on the nucleotide sequence of the 16S ribosomal RNA gene. Compared with B. amyloliquefaciens KCTC1660, whose genome has been sequenced, the isolate exhibited significantly low activities of starch-degrading enzymes and high resistance to high temperature and low pH.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.4
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• pp.265-270
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• 2014

Protease producing microorganisms were isolated from many kinds of food waste and fermented foods, which contains high amount and variable kinds of degraded substances. Several microorganisms were identified by 16S rRNA full sequencing analysis methods. The activity of protease was analyzed and identified in variable conditions for the application. For industrial use for biowaste treatment some proteases were isolated, identified and selected from microbial cells. And the tests were carried for the further use. The protein degrading activity at low temperature is useful for the treatment of organic waste, which contains much proteins. By the protein degradation process the organic waste can be utilized in variable fields, for example from feedstuff supplement to fertilizer for agriculture. Bacterial cells with protease activity at low temperature were isolated and identified. The optimal conditions for microbial cultivation and protease production were studied.

• Biomedical Science Letters
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• v.6 no.3
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• pp.209-221
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• 2000

The purpose of this study was to investigate the practical availability of pretense production that can be used at home after isolating Serratia sp.2000-1 which produced extracellular pretense from clinical specimen. Basic production conditions and partial enzymatic characteristics of pretense produced by Serratia sp. 2000-1 was as follows: The kind and concentration of carbohydrate, nitrogen and metal salts for optimal enzyme production condition were each identified as the concentration of 1.5% glucose, 2.0% CSP, and 0.1% CaCl$_2$, and the optimal temperature, time and initial pH for culture were each 3$0^{\circ}C$, 72 hours, and pH 8.0. The final enzymatic yeild that was purified by 3 steps with ammonium sulfate precipitation (45~80%), DEAE-cellulose column chromatography, and Sephadex G-200 gel chromatography was 14.4%, and enzyme inactivity rate increased approximately 291314s. The optimal temperature and pH for purified pretense activity were 35$^{\circ}C$ and pH 7.0~8.0, and purified pretense activity was relatively stable by 4$0^{\circ}C$ at pH 6~10 for 30 min, however heating at 6$0^{\circ}C$ for 30 min, it liminated detectable pretense activity. The pretense activity was activated by $Mg^{2+}$, $Ba^{2+}$, $Ca^{2+}$, Mn$^{2+}$, but inactiviaed by Hg$^{2+}$, Ag$^{2+}$, Cu$^{2+}$, and the pretense activity was inhibited strongly by SDS among enzyme activity inhibitors. Further study is required to evaluate the practical availability of pretense production that can be used at home by isolating Serratia sp. from more clinical specimen and examining pretense more in details.

• The Journal of Natural Sciences
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• v.17 no.1
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• pp.55-64
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• 2006

The construction, purification, and characterization of hexahistidine-tagged phage K11 lysozyme are carried out in this study. The results showed that the enzymatic activities of K11 lysozyme are not affected by the purification tag. The optimum pH of K11 lysozyme is 7.2-7.4. The amidase activity of K11 lysozyme was also measured in the presence of different cations. The addition of $Ca^2+$ and $Mg^2+$ almost completely shut down the amidase activity but $Zn^2+$ and $Na^+$ maintained the amidase activity. In the presence of 100 mM $Zn^2+$ the amidase activity was nearly abolished.

• Journal of Life Science
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• v.8 no.6
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• pp.737-740
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• 1998

Effect of oral administration with fibrinolytic enzyme isolated from fermented anchovy(the traditional fermented food in Korea called Myulchi Jeot-gal) and its functionally active enzyme to rat, activation of plasma fibrinolysis was observed. The euglobulin fibrinolytic activities and the plasma levels of H-D-Val-Leu-Lys-pNA(S-2251) amidolysis reached a maximum at 3 hours after the administration to rat. And euglobulin Iysis time(ELT) value after oral admi-nistration showed its activity 2∼3 hours later. From the above result, it was confirmed the enzyme activity in blood by oral administration fibrinolytic enzyme through animal experiment.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.284-291
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• 2003

Bacillus amyloliquefaciens K-42, which produces strongly a fibrinolytic enzyme, Was isolated from Ganjang, a traditional Korean soy sauce. The fibrinolytic enzyme was purified to homogeneity by ammonium sulfate fractionation, ion-exchange chromatography on DEAE-Sephadex A-50, gel chromatography on Sephadex G-100, and gel chromatography on Sephadex G-75 of the culture filtrate of Bacillus amyloliquefaciens K42. The purified enzyme showed the specific activity of 59.4 units per milligram, which was increased by 17.1 fold over the culture broth. And the molecular weight of purified fibrinolytic enzyme was confirmed to be about 45,000 Dalton by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The enzyme activity was relatively stable at pH 4.0-10.0 and the optimum pH was 8.0. The activity of the purified enzyme was increased by $Mg^{2+}$ , Cu$^{2+}$ but the enzyme was totally inhibited by $Ba^{2+}$ $Hg^{2+}$ In addition, the enzyme activity was potently inhibited by EDTA, EGTA and CDTA. It was concluded that the purified enzyme was a metalloprotease. And Km value was 2.03 mg/ml to fibrin.

• Korean Journal of Food Science and Technology
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• v.52 no.1
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• pp.75-80
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• 2020

This study was conducted to compare the functional component content, antioxidant activity, and nitric oxide (NO) inhibition effect of non-enzyme treated, enzyme-treated, and commercial noni juice samples. Enzyme-treated noni juice samples were prepared by cellulase (0.1%) and pectinase (0.1%) treatment of unripe fruits (EUN) and ripe fruits (ERN). Total polyphenol content of the noni juice samples ranged between 0.36 and 1.61 mg/mL. The EUN had the highest total polyphenol content (1.61 mg/mL), while the ERN had the highest scopoletin content (123.88 ㎍/mL) and the highest antioxidant activity. Nitric oxide levels in ERN and NJ5 were lower (55.95 and 60.14%, respectively) than those in other samples. Based on these observations, it was confirmed that enzyme treatment could improve the functional component content and physiological activity of noni juice. In particular, EUN prepared using the ripened noni fruit is expected to have greater utilization value due to its enhanced functionality.