• International Journal of Industrial Entomology and Biomaterials
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• v.17 no.2
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• pp.197-200
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• 2008

The antioxidant activity of Isaria (Paecilomyces) sinclairii was determined by measuring its radical scavenging effect on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radicals. The n- BuOH extract of P. sinclairii showed strong scavenging activity to DPPH. The anti-oxidant potential of the individual fraction was in the order of ethylacetate> n- BuOH>chloroform>n-hexane. The n-BuOH soluble fraction exhibiting strong anti-oxidant activity was further purified by repeated silica gel column chromatography. N-(2-Hydroxyethyl)adenosine (HEA) was isolated as one of the active principles from the n-BuOH layer. The n-BuOH layer, particularly HEA, did not increase the level of nitric oxide (NO) production in vascular endothelial cells that might be related to vasorelaxation such as the action of viagra. In addition, the vascular endothelial growth factor (VEGF) levels showed little or no increase compared with control group with the treatment of I. sinclairii.

• The Korean Journal of Food And Nutrition
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• v.11 no.6
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• pp.678-682
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• 1998

A strain of Streptomyces sp. SK-862, isolated from soil in Wonju city, was able to prodce a biologically active substance that has a strong inhibitory activity against proteolsis by trypsin. The inhyibitory substance was extracted by n-butanol, and then purified by the adsorption chromatography followed by the reverse-phase high performacne liquid chromatography. The purified substance was stable over the pH range from 2 to 10, but was unstable when treated at 8$0^{\circ}C$ for 60 min. This substance was soluble in water, methanol, ethanol nd butanol, but insoluble in chlorofrom and ethylacetate. The Rf value of the purified substance on the thin layer chromatography were 0.56 in n-butanol : methanol : water(5 : 3 : 1v/v) solvent system compare dto 0.23 in ethanol : ammonium hydoxide : water(8 : 1 : 1v/v) solvent system. This substance has maximum absorption at 259 nm. The chemical reaction of the substance was negative for sugar but positive for ninhydrine and iodine reaction.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.863-867
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• 2004

$\alpha$-Galactosidase from A. oryzae DR-5 was induced in the presence of melibiose, raffinose, galactose, and locust bean galactomannan. The enzyme was purified to homogeneity by precipitation with acetone followed by ion-exchange chromatography using DEAE-Sephacel. The purified enzyme showed a single band in both nondenaturing-PAGE and SDS-PAGE. The enzyme was a glycoprotein in nature by activity staining. The molecular weight of the purified enzyme was 93-95 kDa by SDS-PAGE. The enzyme exhibited the optimum pH and temperature at 4.7 and $60^\circ{C}$, respectively. $\alpha$-Galactosidase activity was strongly inhibited by $Ag^{2+}, Hg^{2+}, Cu^{2+}$, and galactose. EDTA, 1,10-phenanthraline, and PMSF did not inhibit the enzyme activity, whereas N-bromosuccinimide completely inhibited enzyme activity. Investigation by TLC showed complete hydrolysis of stachyose and raffinose in soymilk in 3 h at pH 5.0 and $50^\circ{C}$.

• Journal of Yeungnam Medical Science
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• v.13 no.1
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• pp.46-58
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• 1996

Inositol 1,4,5-triphosphate($InsP_3$) is a second messenger for mobilizing intracellular $Ca^{2+}$. It can be dephosphorylated by soluble and particulate forms on $InsP_3$ 5-phosphatase, or phosphorylated to produce inositol 1,3,4,5-tetrakisphosphate($InsP_3$) by $InsP_3$ 3-kinase. These enzymes represent possible targets for the regulation of the $InsP_3/InsP_4$ signal. $InsP_3$ 3-kinase which catalyses th ATP-dependent phosphorylation of $InsP_3$ was purified from bovine brain tissue. All operation were carried out at $4^{\circ}C$. Fresh tissure was homogenized and centrifuged. The supernatant was pooled. Proteins were precipitated from 10% polyethylene glycol, and suspended solution was applied to DEAE cellulose column for chromatography. As the result of above procedure, two isozymes of $InsP_3$ 3-kinase, I and II were obtained. Each isozyme was applied to Matriz green gel, Calmodulin-Affigel 15 column and subsequent phenyl-TSK HPLC column. Specific activites(SA) and fold of puriety were observed at each purification step of chromatography. At DEAE cellulose chromatography, SA were I, 0.6 and II, 4.8 nM/min/mg, and folds were I, 17.2 and II, 16.6. At Matrix green gel chromatography, SA were I, 18 and II, 11 nM/min/mg, folds were I, 62.1 and II, 38.0. At calmodulin-Affigel 15 column chromatography, SA were I, 19 and II, 13 nM/min/mg, folds were I, 65.5 and II, 44.8. Finally $InsP_3$ kinase I and II were purified 3,103-fold and 2,310-fold, and SA were I, 900 and II, 670 nM/min/mg, respectively. SDS-polyacrylamide gel electrophoresis elucidated 3 distinct fractions of Mr of 145,000, 85,000 and 69,500 from isozyme I, and 2 distinct fractions of Mr of 79,000 and 57,000 from isozyme II.

• Journal of the Korean Magnetic Resonance Society
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• v.16 no.1
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• pp.34-45
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• 2012

Melanocortin-4 receptor (MC4R) subtype is associated with obese humans. Especially, in a patient with severe early-onset obesity, novel heterozygous mutation in the MC4R gene was detected, resulting in an exchange of aspartic acid to asparagine in $90^{th}$ amino acid residue located in the predicted second trans-membrane domain (TM2). Mutations in the melanocortin-4 receptor (MC4R) gene are the most frequent monogenic causes of severe obesity which have been described as heterozygous with loss of function. In order to compare structure difference between MC4R wild type (MC4R-TM2-wt) and mutant (MC4R-TM2-D90N), we designed both MC4R-TM2-wt and MC4R-TM2-D90N construct in pET 21b vector. In this study, we optimized high-yield purification procedure for recombinant TM2-D90N. Eluted recombinant protein was resolubilized under urea condition for thrombin cleavage reaction and we conducted the high-performance liquid chromatography (HPLC) with reverse phase column under 1% acetonitrile, 0.01% TFA buffer solution. The molecular size of purified target peptide was confirmed by Tricine-SDS page analysis. To characterize MC4R-TM2-D90N, we have performed $^{15}N$-isotope labeling of peptide using M9 media and purified labeled target peptide for hetero-nuclear NMR spectroscopy.

• Archives of Pharmacal Research
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• v.18 no.5
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• pp.301-307
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• 1995

In the particulate fraction obtained from PKC-down regulated K562 cells by treatment for 24 h with 200nM TPA, phosphorylation of two proteins with molecular weight, 100 kDa and 23 kDa (designated p100 and p23, respectvely) was depleted and addition of exogenous purified PKC to this fraction failed to testore their phosphorylation. However, in the soluble fraction, all of phosphoproteins abolished by long-term treatment with TPA were restored by exogenously added PKC. Phosphorylation of two proteins was increased by short-term tretment (20 min), and diminished with the persistant exposure to TPA as well as at a concentration as low as 1nM. When K562 cells were treated with 1 nM and 200 nM TPA for 24 h, phosphorylation of p100 was restored with or without exogenous PKC on 2-3day and 6day after removal of treated TPA, respectively. Two-dimensional electrophoresis of phosphoproteins revealed that phosphorylated p100 (pl=5.9) and p66 species were completely absent from the particulate fraction of K562 cells treated with 200nM TPA for 24 h. These results suggest that the interaction of sensitive endogenous substrates, p100 and p23 with the plasma membrane might be regulated by PKC-down regulation without displacement to the cytosol and the interaction of p100 with the membrane might be reveersible.

• International Journal of Industrial Entomology and Biomaterials
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• v.2 no.2
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• pp.167-172
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• 2001

The vitellin of firefly, Pyrocoelia rufa, is composed of three polypeptides, designated Vn1 (175 kDa), Vn2 (160 kDa) and Vn3 (45 kDa) in SDS-polyacrylamide gel electrophoresis. Three subunits of vitellin were presented in the female adult hemolymph, ovary and egg extracts, but not observed in the male. This vitellin was purified from the eggs of P. rufa by the FPLC techniques, anion exchange chromatography and gel permeation chromatography. In nature, vitellin of P. rufa has molecular weight of 400 kDa. Western blot analysis using polyclonal antiserum against purified vitellin showed that the antiserum was reacted with the three polypeptides, Vnl, Vn2 and Vn3 from the female adult hemolymph, ovary and egg extracts. Amino acid residues at N-terminus of three subunits were sequenced. The N-terminal sequences of large subunits, Vnl and Vn2, were similar to each other, But, the N-terminal sequences of small subunits Vn3, did not have any signnificant homology with large subunits.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.5
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• pp.191-195
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• 2002

Chemical mechanical Polishing (CMP) process is widely used for the global planarization of inter-metal dielectric (IMD) layer and inter-layer dielectric (ILD) for deep sub-micron technology. However, as the IMD and ILD layer gets thinner, defects such as micro-scratch lead to severe circuit failure, which affect yield. In this paper, for the improvement of CMP process, deionized water (DIW) pressure, purified $N_2$ ($PN_2$) gas, point of use (POU) slurry filler and high spray bar (HSB) were installed. Our experimental results show that DW pressure and P$N_2$ gas factors were not related with removal rate, but edge hot-spot of patterned wafer had a serious relation. Also, the filter installation in CMP polisher could reduce defects after CMP process, it is shown that slurry filter plays an important role in determining consumable pad lifetime. The filter lifetime is dominated by the defects. However, the slurry filter is impossible to prevent defect-causing particles perfectly. Thus, we suggest that it is necessary to install the high spray bar of de-ionized water (DIW) with high pressure, to overcome the weak-point of slurry filter Finally, we could expect the improvements of throughput, yield and stability in the ULSI fabrication process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.811-814
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• 1993

Properties of a protease purified from Sarcodon asparatus(Berk.) S. Ito have been investigated. The enzyme displays as a glycosylated serine protease. The sequence for the 21 amino acids of the N-terminal side in the enzyme was determined by automated sequence analysis. The sequence was V-T-T-K-Q-T-N-A-P-W-G-L-G-N-I-S-T-T-N-K-L-.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.112-118
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• 2004

Laccase produced by Trametes hirsuta S1 isolated from Korea was partially purified and characterized using ultrafiltration, anion exchange chromatography and affinity chromatography. The laccase was produced as the predominant extracellular enzyme during primary metabolism. Neither lignin peroxidase nor veratryl alcohol oxidase (VAO) were detected in the culture fluid. Addition of 2,5-xylidine enhanced 4-fold laccase production. Purified laccase was a single polypeptide having a molecular mass of approximately 66 kDa, as determined by SDS-polyacrylamide gel electrophoresis, and carbohydrate content of 12%. $K_{m}\;and\;V_{max}$ values for laccase with ABTS [2,2-azinobis (3-ethylbenzthiazoline 6-sulfonic acid)] as a substrate (Lineweaver-Burk plot) was determined to $51.2\;{\mu}M\;and\;56.8\;{\mu}mole$, respectively. The optimal pH for laccase activity was found to be 3.0. The enzyme was very stable for 1 hour at $50^{\circ}C$. Half-life ($t_{1/2}$) of the enzyme was about 20 min at $70^{\circ}C$. Spectroscopic analysis of purified enzyme indicated that the enzyme was typical of copper-containing protein. Substrate specificity and inhibitor studies for laccase also indicated to be a typical fungal laccase. The N-terminal amino acid sequence of the T. hirsuta S1 laccase showed 100% of homology to those of laccase from C. hirsutus.