• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.3
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• pp.185-190
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• 1988

Soybean lipoxyeenase isozymes were isolated from acetone-defatted soybean seeds(Glycine max [L.] Merr. variety AmSoy) by ammonium sulfate fractionation, eel filtration, and ion exchange chromatoeraphy. The final preparation of lipoxygenase-1 and -2 obtained was 19- and 32-fold purified, respectively, to the crude extract. But a considerable loss of total enzyme activity occurred during purification. On 7% polyacrylamide gel electrophosis at pH 9.0, employing lipoxigenase specific staining technique, lipoxyeenase-1, -2, and -3 showed distinctive Rf values of 0.38, 0.29, and 0.33, respectively.

• Animal cells and systems
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• v.3 no.1
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• pp.47-52
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• 1999

Change of proteins was confirmed during low temperature acclimation of overwintering larva, and some biochemical characteristics of the induced antifreeze protein-1 (AFP-1) were investigated in Protaetia brevitarsis. As the freezing point depression by the action of induced AFPs, a considerable thermal hysteresis was observed in the haemolymph and in partially purified proteins. AFP-1 was purified from the cold acclimation larvae by ammonium sulfate precipitation ion exchange chromatography, gel permeation chromatography, and electroelution. The purified AFP-1 was determined to be a glycoprotein (approximately 320 kDa, pl 5.8) composed of a single type of subunit (80 kDa). The high contents of hydrophilic amino acids (Asp, Glu, Lys, Asn, Gln, Arg, Ser, Thr) were also confirmed, showing similarity with antifreeze proteins from other insects.

• Journal of Microbiology
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• v.38 no.2
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• pp.74-79
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• 2000

For the demonstration of a novel riboflavin kinase assay method based on the bacterial bioluminescence, partially purified riboflavin kinase was prepared from bovine liver through ammonium sulfate precipitation and DEAE-cellulose ion exchange chromatography. Using bacterial luciferase from Photobacterium phosphoreum and the dithionite reduction method, and easy, safe, and fast assay method was established. The optimal temperature, pH, Km values form riboflavin and ATP of boving liver riboflavin kinase determined with this luminescence method were 35$^{\circ}C$, pH 7, 15.3${\mu}$M and 8.3.${\mu}$M, respectively. The detection limit of FMN produced by riboflavin kinase was in the range of 200 pM to 4${\mu}$M which is comparable to the HPLC-fluorescence detection method, while the detection time for each assay was less than 15 sec compared to the HPLC method which requeires at least 10 min for completion.

• Korean Journal of Microbiology
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• v.26 no.1
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• pp.52-59
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• 1988

A partially purified preparation of L-galactonolactone oxidase which catalyzes the last step of L-ascorbic acid biosynthesis was obtained from Saccharomyces cerevisiae ATCc 26787. The purification procedures included Triton X-100 treatment, protamine sulfate precipitation, ammonium sulfate precipitation, DEAE-Sepharose CL-6B ion exchange chromatography, Sephadex G-150 gel filtration chromatography, and Phenyl-Sepharose CL-4B hydrophobic interaction chromatography. The optimum temperature for the enzyme activity was about $34^{\circ}C$ and the optimum pH was 6.8-7.0. The substrate specificity was confined to L-aldonolactones, L-galactono-1,4-lactone and L-gulono-1,4-lactone. An apparent Km value of 0.294mM with L-galactono-1,4-lactone as a substrate was found. By comparing the substrate specificities of this enzyme with those of isofunctional enzymes of higher plants and animals, it becomes evident that the enzyme of S. cerevisiae ATCC 26787 is rather similar to the L-gulonolactone oxidase of animals than the galactonolactone dehydrogenase of higher plants.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.446-451
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• 1999

The protease produced by Mucor racemosus f. racemosus PDA 103 from meju was purified by precipitating with 80% saturated ammonium sulfate, CM Sephadex C-50 ion-exchange chromatography, and secondary Sephadex G-100 gel filtration chromatography. The specific activity of the purified enzyme was 60.1unit/mg protein and the purification fold of the enzyme was 83.5. The molecular weight of the enzyme was estimated 33,746Da and the enzyme was elucidated as monomer by LC-MS and SDS-PAGE. The number of amino acids was evaluated about 330 residues.

• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.322-328
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• 1995

A thermophilic bacteria showing proteolytic activity against defatted soybean was isolated from soil. It was identified as Bacillus amyloliquefaciens based on its morphological and physiological characteristics. The Bacillus amyloliquefaciens NS 15-4 was cultivated at 50$\circ$C by rotary shaking in a medium containing defatted soybean. An extracellular protease from this strain was purified to homogeneity by ammonium sulfate precipitation, ion exchange, and hydrophobic interaction chromatographies. The molecular weight of the enzyme was estimated to be approximately 30,000 by SDS-PAGE and the N-terminal amino acid sequence of the enzyme was turned out to be AQSVPYGISQIKAPA. The optimum temperature and pH for the enzyme reaction were 60$\circ$C and 11, respectively, and its thermostability was increased by the addition of calcium ion. The enzyme was inactivated by phenylmethylsulfonylfluoride, suggesting it be a serine protease. Comparing with other commercial proteases, the enzyme showed relatively high proteolytic activity against defatted soybean, a water-insoluble protein substrate.

• Preventive Nutrition and Food Science
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• v.3 no.2
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• pp.152-156
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• 1998

A Fructan-degrading enzyme was partially purified from onion (Allium cepa)bulbs by a combination of ammonium sufate precipitation, concanavalin-A-Affinity chromatography, and ion-exchange and gel-filtration chromatography. The enzyme hydrolyzed sucrose more effectively than inulin and was identified as a $\beta$- fructofuranosidase (invertase). The optimum pH and temperature were pH 5.5 and 35$^{\circ}C$, respectively. The enzymehydrolyzed sucrose with a Km of 1.2mM . The soluble $\beta$-fructofuranosidase is likely glycoprotein based on its ability to bind the lectin concanavalin-A. The enzyme was heatlabie, with mose activity being lost at 5$0^{\circ}C$ in 1 hr of incubation. The onion $\beta$-fructofuranosidase was partially inhibited by ZnCl2 HgCl2 and CuSo4.

• Nuclear Engineering and Technology
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• v.4 no.2
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• pp.83-89
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• 1972

The contents of the individual lanthanide elements are determined by neutron activation using a new comparator technique, which employs the short-lived radio-isotope of 56Mn as a neutron flux monitor. The total rare earths are separated as a group from the monazite sample before irradiation. After irradiation the rare earths are separated from each other by gradient elution with ammonium alpha-hydroxyisobutyrate using a cation-exchange column. The contents of 14 individual rare earths, from lutetium to lanthanum, are deter-mined.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.146.1-146.1
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• 2003

A major protein was isolated from ginseng root (Panax ginseng C.A. Meyer) using a combination of ammonium sulfate fractionation, gel filtration chromatography, ion-exchange FPLC. Electrophoretic and gel permeation chromatographic studies revealed that the major protein, GMP, is composed of two subunits of approximately 28 kDa. In this, investigated the ability of GMP to inhibit the oxidation of low-density lipoprotein (LDL). GMP inhibited $Cu^{2+}$ (5$\mu$M)-promoted oxidation of LDL (125$\mu$g protein/mL) in a dose-dependent mamer (0~5 $\mu$M), with a maximal inhibitor at GMP/copper ratio of 1:10 and an $IC_{50}$ value of 0.2 $\mu$M, as determined by measurement TBARS. (omitted)

• Membrane Journal
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• v.32 no.5
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• pp.348-356
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• 2022

With the development of the bio industry, membrane chromatography with a high adsorption efficiency is emerging to replace the existing column chromatography used in the downstream processes of pharmaceuticals, food, etc. In this study, through the deacetylation reaction of two commercial cellulose acetate (CA) membranes with different pore sizes, the porous regenerated cellulose (RC) supports for membrane chromatography were obtained to attach the anion exchange ligands. The adsorptive membranes for anion exchange were prepared by attaching an anion exchange ligand ([3-(methacryloylamino) propyl] trimethylammonium chloride) containing quaternary ammonium groups on the RC supports by grafting and UV polymerization. The protein adsorption capacities of the prepared membranes were obtained through both the static binding capacity (SBC) and the dynamic adsorption capacity (DBC) measurement. As a result, the membrane chromatography with the smaller the pore size, the larger the surface area showed the highest protein adsorption capacity. Membrane chromatography which was prepared by using deacetylated commercial CA support with MAPTAC ligand (i.e., RC 0.8 + MAPTAC: 43.69 mg/ml, RC 3.0 + MAPTAC: 36.33 mg/ml) showed a higher adsorption capacity compared to commercial membrane chromatography (28.38 mg/ml).