• BMB Reports
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• v.38 no.1
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• pp.58-64
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• 2005

Myo-inositol monophosphate phosphatase (IMPP) is a key enzyme in the phosphoinositide cell-signaling system. This study found that incubating the IMPP from a porcine brain with pyridoxal-5'-phosphate (PLP) resulted in a time-dependent enzymatic inactivation. Spectral evidence showed that the inactivation proceeds via the formation of a Schiff's base with the amino groups of the enzyme. After the sodium borohydride reduction of the inactivated enzyme, it was observed that 1.8 mol phosphopyridoxyl residues per mole of the enzyme dimer were incorporated. The substrate, myo-inositol-1-phosphate, protected the enzyme against inactivation by PLP. After tryptic digestion of the enzyme modified with PLP, a radioactive peptide absorbing at 210 nm was isolated by reverse-phase HPLC. Amino acid sequencing of the peptide identified a portion of the PLP-binding site as being the region containing the sequence L-Q-V-S-Q-Q-E-D-I-T-X, where X indicates that phenylthiohydantoin amino acid could not be assigned. However, the result of amino acid composition of the peptide indicated that the missing residue could be designated as a phosphopyridoxyl lysine. This suggests that the catalytic function of IMPP is modulated by the binding of PLP to a specific lysyl residue at or near its substrate-binding site of the protein.

• Journal of Plant Biotechnology
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• v.31 no.3
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• pp.231-237
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• 2004

Oxycarotenoids are oxygenated carotenoids that perform critical roles in plants. $\beta$-Carotene hydroxylase adds hydroxyl groups to the $\beta$-rings of carotenes and has been cloned from several bacteria and plants including Arabidopsis. This study was carried out to investigate the effect of $\beta$-carotene hydroxylase gene (Chyb) on the oxycarotenoids biosynthesis in the transgenic Arabidopsis. Construct of pGCHYB containing Chyb was established onto Gateway vector system (pENTR3C gateway vector and pH2GW7 destination vector). Arabidopsis thaliana (cv. Columbia) was transformed with Agrobacterium tumerfacience GV3101 harboring pGCHYB construct driven by 35S promoter and hygromycin resistant gene. Seven hundred bases paired PCR products, indicating the presence of Chyb gene, were found in the transformants by PCR analysis using Chyb primers. Hygromycin resistance assay showed that transgenes were stably inherited to next generation. The overexpression of the Chyb gene resulted in the decrease carotenoid content. Especially, astaxanthin unusual oxycarotenoid in wild type Arabidopsis was detected in the transgenic plants. This means that decreased carotenoids might be converted into astaxanthin metabolism with the aid of silent gene in the host.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.171-177
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• 1998

The strain A49, which produces a new type of extracellular polysaccharide was isolated from soil samples. From morphological, physiological and biochemical tests, the strain A49 was identified as a Bacillus polymyxa and named Bacillus polymyxa A49. Bacillus polymyxa A49 was found to produce a highly viscous extracellular polysaccharide when grown aerobically in a medium containing glucose as the sole source of carbon. The polysaccharide (A49 POL) showed a homogeneous pattern on gel permeation chromatography (GPC) and its molecular weight was estimated to be about 1.6 mega dalton (mDa). The FT-IR spectrum of A49-POL revealed typical characteristics of polysaccharides. As a result of investigations with HPLC and carbozole assay, A49-POL was found to consist of L-fucose, D-galactose, D-glucose, D-mannose, and D-glucuronic acid, with the molar ratio of these sugars being approximately 1:2:7:50:12. Rheological analysis of A49 POL revealed that it is pseudoplastic and has a higher apparent viscosity at dilute concentrations than does xanthan gum. The consistancy factor of A49 POL was found to be higher, and the flow index of A49 POL lower, than xanthan gum. Its apparent viscosity was comparatively unstable at various temperatures. the A49 POL showed the highest apparent viscosity at pH 3. When salts were added to A49 POL solution, the solution was compatible with up to 10% KCl, 35% NaCl, 55% $CaCl_2$, 55% $MgCl_2$, 55% $K_2HPO_4$, and 110% $Ca({NO_3})_2$, respectively.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.985-990
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• 2004

Levans produced from Microbacterium laevaniformans were isolated, characterized, and fractionated by molecular weight. TLC, HPLC, and GC-MS analyses of the exopolysaccharide showed that it was a fructan-type polymer and was composed of (2,6)- and (2,1)-glycosidic linkages. $^{13}C$-NMR analysis proved that the polysaccharide was mainly a $\beta$-(2,6)-linked levan-type polysaccharide. To investigate the cytotoxicity of the acetone-precipitated levan fractions such as M1, M2, and M3, HepG2, P388D1, U937, SNU-1, and SNUC2A cell lines were screened. Among the cell lines tested, the cytotoxicity of M1- M3 fractions were detected from only SNU-1 and HepG2 cells at the dosage level of $100-800\mu\textrm{g}ml$. The M2 fraction M_r$, 80,000) at 400 $mu{g/ml}$ had the greatest cell growth inhibition (84.6%) on SNU-1, while the M1 $(M_r$, 50,000) at $800\mu\textrm{g}ml$ showed the greatest (46.32%) on HepG2. To obtain more uniform M_r$ fractions of levan, the levan was further fractionated from S1 $(M_r$ 1,000,000) to S5 $(M_r$ 10,000) using gel permeation chromatography. Again, the S1-S5 fractions had strong cytotoxicity on SNU-1 and HepG2 cell lines. The greatest inhibition effects of S4 $(M_r$ 80,000) on SNU-1 and S5 $(M_r$ 10,000) on HepG2 were shown to be 49.5% and 73.0%, respectively. The cytotoxicity of the levan fractions was more effective on SNU-1 than on HepG2. Although the relationship between the Mw and the cytotoxicity was not clear, smaller $M_r$, fractions of levan showed greater growth inhibition effect on the cancer cell lines in general. Therefore, it was indicated that a specific Mw class of levan is responsible for the effective cytotoxicity.

• Asian Journal of Atmospheric Environment
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• v.5 no.3
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• pp.146-151
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• 2011

1-Nitropyrene (1-NP), 2-NP and 2-nitrofluoranthene (2-NFR) are useful markers for studying the atmospheric behaviors of polycyclic aromatic hydrocarbons (PAHs) and nitropolycyclic aromatic hydrocarbons (NPAHs). However, present methods for measuring trace levels of these compounds are lesssensitive and laborious. Here we describe several improvements to a previously reported high-performance liquid chromatography-chemiluminescence detection system that allows it to determine trace levels of 1-, 2-NPs and 2-NFR. The proposed system was equipped with a reducer column packed with Pt/Rh instead of zinc whose life-time was limited. The combination of Cosmosil MS-II (monomeric ODS) and AR-II (polymeric ODS) columns was used instead of polymeric ODS columns as the separator column to improve the separation. An ethanol mixture with acetate buffer (pH 5.5) was used in place of an acetonitrile mixture with the same buffer to activate the reducer column. The same ethanol mixture was used as the mobile phase for the clean-up column. The switching time of the column switching valve was optimized to concentrate the amino-derivatives of above NPAHs quantitatively on the concentrator column. The concentrations of bis(2,4,6-trichlorophenly) oxalate and hydrogen peroxide in the chemiluminescence reagent solution were optimized to 0.4 mM and 30 mM, respectively, to increase the sensitivity. Under the above conditions, the detection limits (S/N=3) of 1-, 2-NPs and 2-NFR were 1 fmol (0.25 pg), 10 fmol (2.5 pg) and 4 fmol (1 pg), respectively. The proposed system was effectively used to determine trace levels of 1-, 2-NPs and 2-NFR in airborne particulates collected at Noto Peninsula. The atmospheric concentrations of 1-, 2-NPs and 2-NFR were not more than sub pg $m^{-3}$ levels. They were higher in winter (January) than in summer (July). In both seasons, the concentrations were in decreasing order, [2-NFR]>[1-NP]>[2-NP].

• Applied Biological Chemistry
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• v.51 no.3
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• pp.188-193
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• 2008

This study was conducted to investigate the effect of moisture content and pressure on extraction yield, crude saponins and ginsenoside contents of puffed Korean ginseng. Puffed ginsengs showed relatively higher extraction yield ($50.0{\sim}62.1%$) and amounts of crude saponins ($19.6{\sim}48.8$ mg/g ginseng) than no-puffed ginseng ($37.6{\pm}0.8%$ and $11.0{\pm}1.0$ mg/g ginseng), respectively. The highest extraction yield and amounts of crude saponins were obtained in 8.0% moisture content sample puffed at 10 $kg_f/cm^2$. In HPLC analysis, amounts of measured major ginsenosides (Rb1, Rb2, Rc, Rd, Re, and Rg1) decreased with increasing puffing pressure, yet contents of almost all major gin senosides were higher than control (no-puffed). On the other hand, ginsenoside Rg3 were produced after puffing suggesting that chemical structure of some ginsenosides might be altered during the puffing process. These results indicate that puffing can increase the extraction yield and crude saponin contents and it could influence the ginsenoside composition.

• Journal of Applied Biological Chemistry
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• v.61 no.2
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• pp.109-117
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• 2018

Recently, cancer incidence in modern society is increasing sharply. DNA damage is caused by intrinsic or extrinsic factors in the human body, cells protect themselves by defense mechanism against DNA damage. Also, Aberrant DNA and deficient DNA repair are closely associated with various diseases, including aging and cancer. Researchers are interested in search for proper materials to inhibition for DNA damage. As knew the side effects of synthetic antioxidant, some researches have been conducted about cancer prevention materials derived from nature. Root of Smilax china, in Liliaceae, is used detoxification and tumor treatments traditionally. However, studies on the inhibitory effect of DNA damage haven't progressed. In this study, antioxidant activity and protective effects on oxidative DNA damage of S. china root were confirmed, relationship between those activities and contents of phenolic compounds in plants were established. S. china root effectively removed 1,1-diphenyl-2-picryl-hydrazyl radicals and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid radicals. The quantification and identification of phenolic compounds were confirmed by high performance liquid chromatography analysis, its antioxidant activity was associated with some phenolic compounds. In addition, protective effects against hydroxyl radicals and ferrous ion-induced oxidative DNA damage were confirmed in plasmid DNA. In the cellular levels, S. china root suppressed the expression of ${\gamma}$-H2AX and p53 protein in NIH 3T3. Besides, S. china root suppressed H2AX and p53 mRNA levels. In conclusion, S. china root had the effect on DNA protection and antioxidant.

• Korean Journal of Clinical Laboratory Science
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• v.39 no.3
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• pp.196-200
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• 2007

In clinical practice, homocysteine has gained popularity because its elevated values are strongly associated with an increased risk of cardiovascular disease. More recently, a new enzymatic colorimetric assay for homocysteine in biological sample, suitable for automated clinical analyzers, has been proposed. To evaluate one of these enzymatic methods and compare the results obtained with this method with those of an immunoenzymatic method, thirty-two samples were analyzed for total homocysteine by HiSens$^{(R)}$ homocysteine reagent on the automated chemistry analyzers TBA 200FR and compared to the widely used immunoenzymatic method ADVIA Centaur. In TBA 200FR, the within-run CVs of two control materials were 3.23% and 0.92%, respectively; the between run CVs were 4.58% and 2.55%, respectively. And in ADVIA 1650, the within-run CVs were 6.81% and 0.99%, respectively; the between run CVs were 9.0% and 3.9%, respectively. The recovery for homocysteine was 100% ($60.8{\mu}mol/L$), 99.1% ($48.64{\mu}mol/L$), 96.3% ($36.48{\mu}mol/L$), 96.1% ($24.32{\mu}mol/L$), and 92.1% ($12.16{\mu}mol/L$). The regression equation of TBA 200FR vs. ADVIA Centaur was y=0.9095x-2.5086 (r=0.9632). And the regression equation for the ADVIA 1650 chemistry vs. Immulite 2000 was y=0.8418x + 0.3207 (r=0.9625). In conclusion, this enzymatic method using automated chemistry analyzer for homocysteine assay shows acceptable analytical performance. I suggest that this assay will be suitable for routine analysis.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.134-140
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• 2004

Optimal extraction method for antioxidant compounds from coat of grape dreg was established. Extracts were prepared with ethanol solutions containing phosphoric, formic, acetic, HCl, TFA, and citric acids. Antioxidant compounds of grape coat were determined by HPLC analysis and evaluated for antioxidizing effects using in vitro model system. Peonidin-3-glucoside content was the highest in 0.1% HCl-added ethanol extract. The extract prepared from pure ethanol without organic acids showed the highest content of cyanidin-3-glucoside among samples tested. Resveratrol and quercetin contents, the most important antioxidants, were highest in 0,1% HCl-added extract. Electron-donating ability was high in 0.1% acetic acid-added extract. SOD-like activities were 95.08% and 94.39% in 0.1% formic and 0.1% citric acid extracts, respectively. Inhibitory effects on peroxidation of egg yolk lecithin were observed in phosphoric (60.51%), citric (59,27%), and formic acid (56,77%) extracts. Hydrogen radical-scavenging activity was 59.47% in 0,1% HCl extract. Results suggest addition of 0.1% HCl in ethanol solution affords the highest yield in antioxidant compounds and antioxidant activities.

• Journal of Pharmaceutical Investigation
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• v.34 no.5
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• pp.413-418
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• 2004

A bioequivalence of $Melax^{TM}$ capsules (Chong Kun Dang Pharm., Korea) and $Mobic^{TM}$ capsules (Boehringer Ingelheim Korea) was evaluated according to the guideline of Korea Food and Drug Administration (KFDA). Single 15 mg dose of meloxicam of each medicine was administered orally to 24 healthy male volunteers. This study was performed in a $2\;{\times}\;2$ crossover design. Concentrations of meloxicam in human plasma were monitored by a high-performance liquid chromatography. $AUC_t$ (the area under the plasma concentration-time curve from time zero to 72 hr) was calculated by the linear trapezoidal rule method. $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma concentration-time data. Analysis of variance was performed using logarithmically transformed $AUC_t$ and $C_{max}$. No significant sequence effect was found for all of the bioavailability parameters. The 90% confidence intervals of the $AUC_t$ ratio and the $C_{max}$ ratio for $Melax^{TM}/Mobic^{TM}$ were 0.95 - 1.04 and 0.98 - 1.14, respectively. This study demonstrated a bioequivalence of $Melax^{TM}$ and $Mobic^{TM}$ with respect to the rate and extent of absorption.