• Journal of Life Science
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• v.12 no.2
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• pp.151-157
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• 2002

A trypsin inhibitor was isolated and purified from Azismatis Rhizoma which has been used as a galenic for diuretic and antiphlogistic. Purification was carried out by 0-80% saturated ammonium sulfate salting out, DEAE- cellulose ion exchange chromatogrphy, Sephadex G-150 gel filtration. The molecular weight of Alismatis Rhizoma trypsin inhibitor(ARTI) was estimated to be about 23,000 Da by gel filtration and SDS-PAGE, it must be monomer. ARTI was stable at 0~6$0^{\circ}C$, but at higher temperature its activity was decreased about 35%. When benzoyl-dl-arginine p-nitroanilide was used as a substrate of trypsin, half-maximal inhibition of ARTI was observed at 0.071 $\mu$M. ARTI inhibited the hydrolysis of trypsin non-competitively and Km value was 0.81 $\mu$M.

• Applied Biological Chemistry
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• v.43 no.2
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• pp.81-85
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• 2000

Screening was performed to isolate biopolymer-producing microorganisms from natural sources. The bacteriological characteristics of this strain and physicochemical properties of the biopolymer produced were investigated. The bacterial strain was identified as a Bacillus coagulans. Crude biopolymer treated with ethanol and actone was purified to fraction I and II by ion exchange chromatography and gel chromatography (Shephadex G-100 and Shepharose CL-2B). Analysis of chemical composition and various color reaction revealed that the polymer is composed of amino acids. It was confirmed that fraction II is a homopolymer of glutamic acid and fraction I is a homopolymer of lysine by analysis data of amino acid analyzer, GC and IR.

• Korean Journal of Microbiology
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• v.26 no.3
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• pp.223-229
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• 1988

Bacillus subtilis K-4-3, which produces considerable amount of $\beta$-glucanase was selected among extracellular $\beta$-glucanase-producing bacteria isolated from soil. $\beta$-glucanase was purified by ammonium sulfate fractionation, Sephadex G-100 gel filtration and DEAE-sephacel ion exchange chromatography. The purified enzyme revealed a single band by polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis. Its molecular weight was estimated to be 17000 dalton by SDS-polyacrylamide gel electrophoresis. The optimum pH and temperature of the purified $\beta$-glucanase were 7.0 and $50^{\circ}C$, respectively. The enzyme was strongly inhibited by 1.0mM of $Fe^{3+}$, and activated by 1.0mm of $Li^{}47+$. The absence of glucose after thin layer chromatography of reaction products revealed that the purified enzyme contains no cellobiase or laminarinbiase activity. The loberation of ki, tri-and tetra-saccharide as reaction products can be explained by endoaction of the enzyme.

• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.456-463
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• 1991

$\beta$-Galactosidase of Bifidobacterium longum KCTC 3215 was studied on the production, purification, and characterization. Optimum conditions for the enzyme production were in the medium of 1.0% lactose as carbon source, initial pH 7.0 and in 17 hours of cultivation at $37^{\circ}C$. The enzyme was purified 9.25 folds by protamine sulfate precipitation, ammonium sulfate fractionation, DEAE-Sephadex A-50 ion exchange chromatography and Sephadex G-150 gel filtration. The maximal P-galactosidase activity was observed at pH 6.5 and at the temperature of $40^{\circ}C$ This enzyme was stable at pH 6.0-8.5. Metal ions such as $Ca^{2+} \;and \; Co^{2+}$, 2-mercaptoethanol, cysteine, and glutathione stimulated B-galactosidase activity. The enzyme activity was inhibited by addition of $Mg^{2+}, Fe^{2+}, Cs^{1+}, Li^{1+}$, DETA, galactose, and $\rho$-chloromercuribenzoic acid. The kinetics of o-nitrophenyl-$\beta$-D-galactopyranoside and lactose were $K_m$ = 1.66 mM, $V_{max}= 0.30 mM/min\cdot mg\cdot protein$ and $KK_m = 3.18 mM, \; V_{max}= 0.42 mM/min \cdot mg\cdot$ protein, respectively. The molecular weight of native enzyme was about 360, 000 dalton and the enzyme consisted of 2 identical subunits with a molecular weight of 180, 000.

• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.477-486
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• 1991

To elucidate enzymatic properties of a-glactosidase (EC 3.2.1.22) from Asp. niger, a-galactosidase from wheat bran culture was purified by ammonium sulfate fractionation, ion exchange chromatography and gel filtration. And then its enzymatic propeties were investigated. The highest level of $\alpha$-galactosidase activity was obtained when Asp. niger was grown on wheat bran medium at $30^{\circ}C$ for 96 hours. The $\alpha$-galactosidase was purified by 23.7 fold by ammonium sulfate fractionation, ion exchange chromatography on DEAE-Celluose and Sephadex A-50, and gel filtration on Sephadex G-150 and its specific activity was 1,229 Unitslmg protein and the yield was 14% of the total activity of wheat bran culture. The purified $\alpha$-galactosidase was found to be homogeneous by polyacrylamide gel electrophoresis and HPLC. The $\alpha$-galactosidase was a tetrameric glycoprotein which consisted of identical subunits with molelcular weight of 28,000 each by SDS-PAGE and isoelectric point was determined analytical isoelectric focusing to be pH 4.6. The optimal temperature and pH for the $\alpha$-galactosidase activity were $40^{\circ}C$ and pH 6.5, respectively, and 54% of its activity was lost by heating at $60^{\circ}C$ for 10 mins, It was appeared to have higher affinty to raffinose than to stachyose. The K, value and activation energy of $\alpha$-galactosidase were 5.0 mM and 8.515 Kcal per mole for p-nitrophenyl- $\alpha$--D-galactopyranoside, respectively.

• Journal of Radiation Protection and Research
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• v.28 no.1
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• pp.25-33
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• 2003

The automatic system for $^{67}Ga$ production using for the diagnosis of malignant tumor has been developed. A solvent extraction and an ion exchange chromatography were used for the separation $^{67}Ga$ from the irradiated enriched $^{68}Zn$. This system consisted of a solvent separation unit which was composed of micro conductivity cells, air supply tubes, solvent transfer tubes, solenoid valves and glasses, a PLC based controller and a PMU user interface unit for automation. The radiation exposure to the workers and the production time can both be reduced by employing this system during the $^{67}Ga$ production phase. After all, the mass production of $^{67}Ga$ with high efficiency was possible.

• Microbiology and Biotechnology Letters
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• v.43 no.4
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• pp.330-335
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• 2015

The optimum conditions for the production of xylanase from Bacillus agaradhaerens DK-2386 have been previously investigated. In this study xylanase was purified by ammonium sulfate precipitation and CM-sepharose ion exchange chromatography. The molecular mass of the xylanase as determined by SDS-PAGE was 23 kDa in a form of monomeric enzyme. The optimum pH and temperature for xylanase activity was 6.0 and $60^{\circ}C$, respectively. Xylanase activity was increased by the addition of EDTA and then stabilized at $40^{\circ}C$ for 24 h. The maximum xylanase activity was obtained when Birchwood xylan was used as a substrate and the $V_{max}$ and $K_m$ were $49,724{\mu}mol/min$ and 6.08 mg/ml, respectively.

• Journal of Sericultural and Entomological Science
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• v.44 no.2
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• pp.64-68
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• 2002

The antibacterial protein gene, nuecin was expressed in Sf9 cells using baculovirus expression vector system (BEVS). The antibactetial activity of mature nuecin against Pectobacterium carotovorum subsp. carotovorum, Ralstonia solanacearum and Pseudomonas tolaasii was significantly high, demonstrating that nuecin had a wider antibacterial spectrum on gram negative and positive bacteria. The result appears to be superior to other antibacterial peptide, attacin. The nuecin was purified by SP-sepharose and Mono Q HR ion-exchange chromatography, and then by Superdex 200 HR 10/30 column. The purified nuecin is quite stable at 80$\^{C}$ and 100$\^{C}$ for several hours of incubation and in a wide pH range (pH 2-12).

• Journal of Chitin and Chitosan
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• v.23 no.4
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• pp.220-227
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• 2018

Amyloid plaque is a product of aggregation of ${\beta}$-amyloid peptide ($A{\beta}$) and is an important factor in the pathogenesis of Alzheimer's Disease (AD). $A{\beta}$ is a major component of amyloid plaque and vascular deposits in the AD brain. The enzyme ${\beta}$-secretase is required for the production of $A{\beta}$; thus, prevention of the formation of $A{\beta}$ through the inhibition of ${\beta}$-secretase is a major focus in the study of the treatment of AD. In this study, we investigated ${\beta}$-secretase inhibitory activity of an Arctoscopus japonicus peptide. An Alcalase hydrolysate had the highest ${\beta}$-secretase inhibitory activity. A ${\beta}$-secretase inhibitory activity peptide was separated using ion exchange column chromatography (carboxy-methyl: CM, quaternary methyl ammonium: QMA) and reverse phase high performance liquid chromatography (RP-HPLC) on a C18 column. The $IC_{50}$ value of the purified peptide was $248.2{\pm}1.73{\mu}g/mL$. The ${\beta}$-secretase inhibitory peptide was identified as a six amino acid residue of Gly-Pro-Val-Gly-Ala-Pro (MW: 497.27 Da). In cell viability experiments, the final purified fraction, the carboxy-methyl ion exchange column fraction (CM-F1) showed no significant cytotoxic effect in SH-SY5Y cells at concentrations below $100{\mu}g/mL$ in 24 h. The results of this study suggest that peptides separated from Arctoscopus japonicus may be beneficial as ${\beta}$-secretase inhibitor compounds in functional foods.

• Animal cells and systems
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• v.1 no.3
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• pp.457-462
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• 1997

Antibacterial activity was induced in the haemolymph of the common cutworm, Spodoptera litura by the artificial injection of E, coli Ek132. Antibacterial peptides were purified from the immunized haemolymph by heat treatment, ion-exchange chromatography, gel filtration chromatography, and reverse phase FPLC, and their physicochemical characteristics were investigated. These purified antibacterial peptides designated as spodopsin la and Ib were named after Spodoptera litura. Spodopsin la and Ib had the apparent molecular masses of 3, 823 Da and 3, 886 Da, respectively, and about 20% of the sequences had basic amino acids, such as lysine and arginine but no cysteine. Also, spodopsin l was confirmed to be a new member of cecropin family having a similar amino acid sequence to cecropin of lepidopteran insects, such as Bombyx mori and Hyalophora cecropia. The purified spodopsin was active against gram-positive as well as gram-negative bacteria.