• Korean Journal of Pharmacognosy
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• v.15 no.2
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• pp.78-84
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• 1984

Polyphenol oxidase was purified from acetone powder extract of the root of Ixeris sonchifolia. The enzyme obtained by ammonium sulfate fractionation and sephadex G-200 gelfiltration gave 51-fold purification over the crude extract. The purified enzyme showed activity toward chlorogenic acid, caffeic acid and pyrocatechol. The kinetics of thermal inactivation of the enzyme followed first-order reaction. Potassium cyanide and cysteine were potent inhibitors.

• BMB Reports
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• v.28 no.3
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• pp.232-237
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• 1995

Arginase was purified to homogeneity from Schizosaccharomyces pombe. The purified enzyme is a tetramer with a subunit molecular weight of 42,000. Activity is optimal at pH 10.0 and at $60^{\circ}C$ The enzyme migrated during isoelectric focusing showing a pl=5.4. The enzyme exhibited hyperbolic kinetics at pH 10.0 with an apparent $K_m$ for L-arginine of 18 mM. Arginase activity was strongly inhibited by L-glutamate.

• The Korean Journal of Food And Nutrition
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• v.7 no.1
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• pp.23-28
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• 1994

Soybean $\beta$-amylase was purified by DEAE-cellulose ion exchange chromatography, Sephadex G-100 gel chromatography, CM Sephadex C-50 ion exchange chromatography and CM Sephadex C-50 ion exchange rechromatography The purified enzyme showed 1, 020 unit/mg of specific activity. The purified enzyme was identified as homogenious by disc PAGE and analysis of reaction product.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.532.2-532
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• 1986

Alkaline protease which is an important enzyme used in detergents, leather tanning and food industry was produced by alkalophilic bacterium, Bacillus sp. KCTC 1723 isolated from soil. The maximum productivity of the enzyme in alkaline medium containing 1% sodium bicarbonate was obtained by incubating for 3 days at 37$^{\circ}C$. The optimum pH of the enzyme was 11.5 and calcium ion was effective on stabilization of the enzyme at high temperature. The enzyme was not inhibited by metal chelating agent such as El)TA but inhibited by diisopropyl fluorophosphate. Purification of the enzyme was carried out DEAE- and CM-cellulose column chromatographies and molecular weight of the purified enzyme was determined

• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.985-989
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• 2002

For efficient biopulping process, very active and stable lignase is essential. Laccase is one of the best enzyme in terms of environmentally benign processes, since the enzyme uses oxygen as an oxidant to degrade lignin and produces no hamful prod ucts. We could purify a laccase homogeneously from Cerrena unicolor in a very active state. It shows characteristic absorption feature with blue band at λmax = 604 ㎚. Molecular weight of the enzyme is 57,608 which could be accurately determined by MALDI/TOF MS. The enzyme has 2.8 copper ions per enzyme implying apoenzymes might exist together. The enzyme is active in lignin degradation and the activity increases 4 times in the presence of ABTS as a mediator.

• Journal of Ginseng Research
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• v.14 no.1
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• pp.14-20
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• 1990

In An invertase (EC 3.2.1.26) was extracted from Korean giseng (Panax ginseng C.A. Meyer) with distilled tvater The ginseng invertase was purified about 62.6 folds purified by procedures including ammonium sulfate fractionation , DEAE-cellulofine chromatography and gelfiltrations through Sephadex G-75 and the recovery of enzyme activity was 11.1%. The homogeneity of the purified enzyme was probed by polyacrylamide gel disc electrophoresis. The purifled enzyme was divided into two different subunits by treating with a mixture of SDS and 2-mercautoethanol, and the molecular weight of the large subunit was estimatedtobe 116,000 and that of the small one to be 14,000. The optimal VH and temperature of the enzyme were pH 6 and 45$^{\circ}C$, respectively. The enzyme hydrolyzed specifically the hydrolyzation of the -fructofuranosides such as sucrose, raffinose and inulin. The Km values of the enzyme for sucrose and raffinose were determined to be 0.85 and 0.6 mM, respectively.

• Microbiology and Biotechnology Letters
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• v.28 no.5
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• pp.258-263
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• 2000

A fibrinolytic enzyme was purified to homogeneity from Bacillus sp. S19 using DEAE and CM column chromatograhies, and gel filtration with a recovery yield of 13%. Its molecular mass was estimated to be 42 kDa by SDS-PAGE. The pH and temperature optima were 8.0 and $40^{\circ}C$, respectively. The enzyme was stable up to $45^{\circ}C$ and over a pH range of 6-9. The N-terminal amino acid sequence of the enzyme was determined as Alsa-Gln-Asp-Ala-Thr-Val-Asn-Ile-Ser-Ala-Glu-Arg-Gln-Val-Ile. The fibrinolytic activity was increased by $Cu^{2+}$ while it was strongly inhibited by metal ions such as $Cd^{2+}$ and $Ba^{2+}$ . In addition, the enzyme was inhibited by EDTA, but not by PMSF, suggesting that it is a metallorprotease.

• The Korean Journal of Food And Nutrition
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• v.7 no.2
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• pp.87-94
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• 1994

A protease, actinidin, was isolated from Cheju kiwi fruit Actinidia chinesis. The enzyme was purified about 8.5 fold with the yield of 25% by column chromatographies of DEAE-Toyopearl and Sphadex. G-100. Purified enzyme gave a single protein band on polyacrylamide gel electrophoresis and its molecular weight estimated by SDS-PAGE was about 27, 000. The optimum pH and temperature were 7.0 and 4$0^{\circ}C$, respectively. This enzyme was stable at the ranges of pH 5.0~9.0 and below 5$0^{\circ}C$. It was also found that Fe+2, Fe+3, and Na+ ions increased enzyme activity, whereas Hg+2 and Co+2 ions decreased. The enzyme was inhibited by phenylmercuric acetate and leupeptin, which indicated that active center of the emzyme had thiol-group. The enzyme reaction followed the Michaelis-Men-ten dkinetics with the Km value of 0.32 mM for casein.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.20-27
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• 2011

The purification and characterization of a $Mn^{2+}$-dependent alkaline serine protease produced by Bacillus pumilus TMS55 were investigated. The enzyme was purified in three steps: concentrating the crude enzyme using ammonium sulfate precipitation, followed by gel filtration and cation-exchange chromatography. The purified protease had a molecular mass of approximately 35 kDa, was highly active over a broad pH range of 7.0 to 12.0, and remained stable over a pH range of 7.5 to 11.5. The optimum temperature for the enzyme activity was found to be $60^{\circ}C$. PMSF and AEBSF (1 mM) significantly inhibited the protease activity, indicating that the protease is a serine protease. $Mn^{2+}$ ions enhanced the activity and stability of the enzyme. In addition, the purified protease remained stable with oxidants ($H_2O_2$, 2%) and organic solvents (25%), such as benzene, hexane, and toluene. Therefore, these characteristics of the protease and its dehairing ability indicate its potential for a wide range of commercial applications.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.161-161
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• 1998

To achieve the aim of this investigation, the extracellular protease was isolated from bacteria BAC-4, a strain was cultivated in the medium for the production of penicillin acilase in a period of 32 hours. The enzyme was first purified by aceton precipitation method, followed by ion exchange chromatography on DEAE-sephacel column. The highest specific activity of the aceton fraction was found to be 2.19 unit per mg, with degree of purification of 13 times. Further purification of the enzyme on DEAE -sephacel had a specific activity of 58.6 unit per mg and degree of purification of 344 times compared to its crude extract. The optimum pH of the enzyme was 8.4, and the potimum temparature was 37$^{\circ}C$. The K$\_$M/ and $V_{max}$ calculated at experiment conditions were found to be 0.66%(W/V) and 3.61 unit per mL respectively.